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1. Dairy farming, cooperatives and livelihoods: lessons learned from six indian villages

Author: Cédric Gaillard, Marie Dervillé, Montpellier Interdisciplinary center on Sustainable Agri-food systems (Social and nutritional sciences) (UMR MoISA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Centre International de Hautes Etudes Agronomiques Méditerranéennes - Institut Agronomique Méditerranéen de Montpellier (CIHEAM-IAMM), Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Laboratoire d'Etude et de Recherche sur l'Economie, les Politiques et les Systèmes Sociaux (LEREPS), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Institut d'Études Politiques [IEP] - Toulouse-École Nationale Supérieure de Formation de l'Enseignement Agricole de Toulouse-Auzeville (ENSFEA), Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), and Département Environnements et Sociétés (Cirad-ES)
Subjects: Economics and Econometrics, Cooperative, 050204 development studies, Smallholders, Poverty reduction, Indian dairy sector, E40 - Coopératives, secteur agro-alimentaire, 0502 economics and business, Coopérative laitière, Revenu de l'exploitation, Livelihoods, 2. Zero hunger, 05 social sciences, 1. No poverty, Moyens d'existence, E80 - Économie familiale et artisanale, [SHS.ECO]Humanities and Social Sciences/Economics and Finance, E20 - Organisation, administration et gestion des entreprises ou exploitations agricoles, Production laitière, 050202 agricultural economics & policy, Finance
Abstract: International audience; India's dairy sector has emerged as the world's largest dairy producer and has enabled 70 million farmers to generate income through its rapid growth. This success is linked to broad national policy support through the Operation Flood program and the emergence of an inclusive model of cooperatives. However, the informal sector is still the marketing channel most used by dairy producers, and with the liberalization of the dairy sector, the cooperative model is also facing competition from the private sector. By surveying 244 dairy farmers in two major but heterogeneous states in India, this paper examines the inclusiveness of the sector and the impact of dairy cooperative membership on farmers’ income and livelihood. The originality of the paper concerns its systematic perspective on households’ assets and activities. The results indicate that cooperative membership is associated with caste membership and farmers collection centers. Better incomes are associated with membership, particularly among farmers with less land and among smallholders, who are more dependent on their dairy income to lift themselves out of poverty.
Published: 2022
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2. Construction and Interpretation of Production and Market Metrics Used to Understand Relationships with Dietary Diversity of Rural Smallholder Farming Households

Author: Cédric Gaillard, Eric O. Verger, Roseline Remans, Andrew D. Jones, Gina Kennedy, Montpellier Interdisciplinary center on Sustainable Agri-food systems (Social and nutritional sciences) (UMR MoISA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Centre International de Hautes Etudes Agronomiques Méditerranéennes - Institut Agronomique Méditerranéen de Montpellier (CIHEAM-IAMM), Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro - Montpellier SupAgro, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), UNIVERSITY OF MICHIGAN SCHOOL OF PUBLIC HEALTH USA, Partenaires IRSTEA, Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Bioversity International [Belgique], Bioversity International [Rome], Consultative Group on International Agricultural Research [CGIAR] (CGIAR)-Consultative Group on International Agricultural Research [CGIAR] (CGIAR), Advancing Nutrition, USAID, Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
Subjects: S01 - Nutrition humaine - Considérations générales, market access and participation, 030309 nutrition & dietetics, Agriculture (General), dietary diversity, Market access, Plant Science, Population rurale, Agricultural economics, Petite exploitation agricole, S1-972, nutrition-sensitive agriculture, Marché des produits de base, 03 medical and health sciences, exploitant agricole, 0502 economics and business, production diversity, Production (economics), Agricultural productivity, E10 - Économie et politique agricoles, 2. Zero hunger, Flexibility (engineering), 0303 health sciences, Food security, business.industry, 05 social sciences, Comparability, [SDV.SA.AEP]Life Sciences [q-bio]/Agricultural sciences/Agriculture, economy and politics, respiratory system, standardized indicators, Agriculture, Diversification, production de produits agricoles, Sécurité alimentaire des ménages, 050202 agricultural economics & policy, Business, Agronomy and Crop Science, human activities, [SDV.AEN]Life Sciences [q-bio]/Food and Nutrition, Food Science, Diversity (business)
Abstract: International audience; Indicators of agricultural production diversity and market access and/or participation have often been used to try to understand how agricultural production and markets influence dietary diversity of rural smallholder households. Based on a standardized search strategy, 37 studies investigating the association between an indicator of agricultural production diversity and any indicator of dietary diversity were reviewed. The characteristics of the indicators of agricultural production diversity, as well as indicators of market access and/or participation, were assessed. This review demonstrated the wide range of indicators; four types and 14 subtypes of indicators of agricultural production diversity were found in the 37 studies, and three types and 14 subtypes of indicators of market access and/or participation were found in 25 studies. While diversity of measurement ideas allows flexibility, it precludes comparability with other studies and might make it difficult to build a robust body of evidence of the impact of agriculture at farm household level on food security, diet, and nutrition.
Published: 2021
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3. Phenolic distribution in apple epidermal and outer cortex tissue by multispectral deep-UV autofluorescence cryo-imaging

Author: Marie-Françoise Devaux, Camille Alvarado, Cédric Gaillard, Kévin Vidot, Marc Lahaye, Frédéric Jamme, René Siret, Sylvain Guyot, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), and Food for Tomorrow programme from the Region Pays de la Loire
Subjects: 0106 biological sciences, 0301 basic medicine, Ultraviolet Rays, Cryo-microscopy, Cuticle, Organoleptic, Plant Science, Biology, 01 natural sciences, Deep-UV synchrotron light, Plant Epidermis, Cell wall, Multispectral imaging, 03 medical and health sciences, Pigment, Phenols, Cortex (anatomy), Stilbenes, Genetics, medicine, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, Flavonoids, Microscopy, Confocal, Epidermis (botany), Cryoelectron Microscopy, General Medicine, Fluorescence, Phenolic compounds, Autofluorescence, 030104 developmental biology, medicine.anatomical_structure, Spectrometry, Fluorescence, Microscopy, Fluorescence, Malus domestica, visual_art, Fruit, Malus, visual_art.visual_art_medium, Biophysics, Agronomy and Crop Science, 010606 plant biology & botany
Abstract: Phenolic compounds in fruit are involved in responses to biotic and abiotic stresses and are responsible for organoleptic properties. To establish the distribution of these secondary metabolites at the tissue and sub-cellular scales, mapping of fluorescence in apple epidermis and outer cortex tissue in cryogenic condition was performed after deep-UV excitation at 275 nm. Douce Moen and Guillevic cider apple varieties were sampled and frozen after harvest, after 30 days at 4 °C and after 20 days at room temperature. Image analysis of fluorescence emission images acquired between 300 and 650 nm allowed the assignment of fluorescence signals to phenolic compound families based on reference molecules. Emission attributed to monomeric and/or condensed flavanol was localized in whole tissue with major fluorescence in the cuticle region. Hydroxycinnamic acids were found predominantly in the outer cortex and appeared in the cell wall. Fluorescent pigments were mostly found in the epidermis. The distribution of flavanols in the sub-cuticle and phenolic acids in the outer cortex distinguished apple varieties. Storage conditions had no impact on phenolic distribution. The proposed fluorescent imaging and analysis approach enables studies on phenolic distribution in relation to fruit development, biotic/abiotic stress resistance and quality.
Published: 2019
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4. Increased diffusivity of lycopene in hot break vs. cold break purees may be due to bioconversion of associated phospholipids rather than differential destruction of fruit tissues or cell structures

Author: P. Reling, Cécile Labadie, Cédric Gaillard, Catherine Caris-Veyrat, Stéphane Georgé, Caroline Garcia, David Page, Pascale Goupy, Romain Bott, Nathalie Bernoud-Hubac, Baptiste Fourmaux, Centre recherche en CardioVasculaire et Nutrition (C2VN), Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Cardiovasculaire, métabolisme, diabétologie et nutrition (CarMeN), Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hospices Civils de Lyon (HCL), Laboratoire national des champs magnétiques intenses - Toulouse (LNCMI-T), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Sécurité et Qualité des Produits d'Origine Végétale (SQPOV), Avignon Université (AU)-Institut National de la Recherche Agronomique (INRA), Centre recherche en CardioVasculaire et Nutrition = Center for CardioVascular and Nutrition research (C2VN), Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hospices Civils de Lyon (HCL), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Hospices Civils de Lyon (HCL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National de la Recherche Agronomique (INRA), National Institute of Research and Agronomy (INRA, France, AIC Factors limiting carotenoids' bioaccessibility during digestion), INRA-France internal program (AIC Carotenoid Bioaccessibility), European Project: 222654,EC:FP7:KBBE,FP7-KBBE-2007-2A,DREAM(2009), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Institut National de la Santé et de la Recherche Médicale (INSERM), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Grenoble Alpes (UGA), and Institut National de la Recherche Agronomique (INRA)-Avignon Université (AU)
Subjects: Bioconversion, [SDV]Life Sciences [q-bio], Cell, Bioaccessibility, 01 natural sciences, Analytical Chemistry, Diffusion, chemistry.chemical_compound, pressure, Lycopene, Solanum lycopersicum, in-vitro bioaccessibility, Micronutrient, Food science, carotenoid bioaccessibility, Carotenoid, Phospholipids, chemistry.chemical_classification, Principal Component Analysis, 04 agricultural and veterinary sciences, General Medicine, Phosphatidic acid, 040401 food science, Chemistry, products, medicine.anatomical_structure, Food Science & Technology, Particle-size distribution, Emulsions, Rheology, Phospholipid, Thermal diffusivity, Food technology, 0404 agricultural biotechnology, human stomach, medicine, carrot, parameters, tomato juice, Nutrition & Dietetics, 010401 analytical chemistry, Water, temperature, Solanum lycopersicum L, Carotenoids, 0104 chemical sciences, Process, chemistry, kinetics, Fruit, [CHIM.OTHE]Chemical Sciences/Other, [SDV.AEN]Life Sciences [q-bio]/Food and Nutrition, Oils, Food Science
Abstract: International audience; Lycopene bioaccessibility is enhanced by processing, as explained by the destructuration of plant tissues, making diffusion easier. However, in tomato, the relationship between grinding intensity and lycopene release from purees suffers from uncertainty. In particular, hot break puree exhibited twice as much diffusible lycopene as compared to cold break, while both were processed with the same grinding intensity. To explain the difference, we systematically studied the diffusivity of particles according to their size and integrity, and used microscopic and physical analyses to reveal structural differences. Neither particle size distribution, nor cell destruction, nor plastid transformation exhibited any correlation to the differences in diffusivity. However, Raman micro-spectroscopy combined with a chemometric analysis revealed significant changes in lycopene spectra and a putative linkage to phospholipid transformation. Phospholipid profiling of five pairs of contrasted purees revealed that, during the cold break, a transition from complex phospholipids to more simple phosphatidic acid molecules systematically occurred.
Published: 2019
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5. Spontaneous formation of nanofilms under interaction of 4th generation pyrydylphenylene dendrimer with proteins

Author: Svetlana A. Sorokina, Zinaida B. Shifrina, Victor S. Stroylov, Cédric Gaillard, Aleksandra K. Melnikova, Vladimir I. Muronetz, Yulia Yu. Stroylova, Thomas Haertlé, Moscow State University, Institute of Molecular Medicine, St. James's Hospital and Trinity College, Russian Academy of Sciences [Moscow] (RAS), ND Zelinsky Institute of Organic Chemistry [Moscow, Russia], Faculty of Bioengineering and Bioinformatics, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Department of Animal Nutrition and Feed Management, University of Life Sciences in Poznan, Teheran University, Partenaires INRAE, RFBR grant [15-38-70034, 16-33-00593], and French Government
Subjects: Dendrimers, Dendrimer-protein composites, Polymers and Plastics, Molecular model, In silico, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Molecular dynamics, chemistry.chemical_compound, Dendrimer, [SDV.IDA]Life Sciences [q-bio]/Food engineering, Materials Chemistry, medicine, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Chymotrypsin, biology, Organic Chemistry, 021001 nanoscience & nanotechnology, Trypsin, 0104 chemical sciences, 3. Good health, Enzymes, chemistry, biology.protein, Biophysics, Lysozyme, 0210 nano-technology, Biosensor, medicine.drug
Abstract: The use of materials based on protein-polymer compositions is a promising method for solving a number of problems in biotechnology and medicine. In our work, we produced multilayer nanofilms based on 4th generation (G4) pyridylphenylene dendrimers with fully pyridine-based periphery containing a protein component. For dairy beta- and kappa-caseins, alpha-lactalbumin, recombinant sheep prion protein, lysozyme, trypsin, and alpha-chymotrypsin the ability to integrate into self-organizing structures about 230–710 nm thick, measured by atomic force microscopy, was found. The formation of nanofilms is dependent on the protein/dendrimer ratio in the initial solution. At the same time, the nanofilms are resistant to pH changes, and the action of detergents. We demonstrated that trypsin and chymotrypsin incorporated into the nanofilms still conserved proteolytic activities and were stable for at least 3 weeks. We have also conducted in silico molecular modeling of the G4 dendrimer interactions with lysozyme. Spatial structure of the dendrimer-protein complex was predicted and most probable variant remained almost intact under 100 ns molecular dynamics simulation conditions. We believe that dendrimer-protein systems are promising tools for possible applications in the development of new stable biomaterials and biosensors.
Published: 2018
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6. Cryo-laser scanning confocal microscopy of diffusible plant compounds

Author: René Siret, Cédric Gaillard, Marc Lahaye, Kévin Vidot, Camille Rivard, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Groupe de Recherche en Agroalimentaire sur les Produits et les Procédés (GRAPPE), Institut National de la Recherche Agronomique (INRA)-Ecole supérieure d'Agricultures d'Angers (ESA), Département Caractérisation et Elaboration des Produits Issus de l'Agriculture (CEPIA), RFI Food for Tomorrow-Cap Aliment, USC 1422 Groupe de Recherche en Agroalimentaire sur les Produits et les Procédés, Ecole Supérieure d'Agriculture (ESA)-Institut National de la Recherche Agronomique (INRA), Vidot, Kévin, Gaillard, Cedric, and Lahaye, Marc
Subjects: 0106 biological sciences, 0301 basic medicine, Cryogenic fixation, [SDV]Life Sciences [q-bio], Grape, Plant Science, lcsh:Plant culture, 01 natural sciences, Cryo-confocal microscopy, 03 medical and health sciences, In vivo, Genetics, Confocal laser scanning microscopy, lcsh:SB1-1110, Sample preparation, lcsh:QH301-705.5, Large field of view, Metallic ions, Chemistry, Methodology, Apple, food and beverages, Cryogenic fixation, Cryo-confocal microscopy, Metallic ions, Phenolics, Apple, Grape, Plant tissue, Fluorescence, Staining, 030104 developmental biology, lcsh:Biology (General), Biophysics, Phenolics, 010606 plant biology & botany, Biotechnology
Abstract: Background The in vivo observation of diffusible components, such as ions and small phenolic compounds, remains a challenge in turgid plant organs. The analytical techniques used to localize such components in water-rich tissue with a large field of view are lacking. It remains an issue to limit compound diffusion during sample preparation and observation processes. Results An experimental setup involving the infusion staining of plant tissue and the cryo-fixation and cryo-sectioning of tissue samples followed by fluorescence cryo-observation by laser scanning confocal microscopy (LSCM) was developed. This setup was successfully applied to investigate the structure of the apple fruit cortex and table grape berry and was shown to be relevant for localizing calcium, potassium and flavonoid compounds. Conclusion The cryo-approach was well adapted and opens new opportunities for imaging other diffusible components in hydrated tissues.
Published: 2018
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7. Molecular and structural changes in gelatin evidenced by Raman microspectroscopy

Author: Anne Duconseille, Cédric Gaillard, Véronique Santé-Lhoutellier, Thierry Astruc, Qualité des Produits Animaux (QuaPA), Institut National de la Recherche Agronomique (INRA), and Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA)
Subjects: food.ingredient, General Chemical Engineering, Analytical chemistry, 02 engineering and technology, cross-links, Gelatin, gelatin, 0404 agricultural biotechnology, food, raman spectroscopy, Denaturation (biochemistry), Food science, dissolution rate, Dissolution, Chemistry, aging, 04 agricultural and veterinary sciences, General Chemistry, 021001 nanoscience & nanotechnology, 040401 food science, Raman microspectroscopy, Lipid content, Digestive tract, 0210 nano-technology, [CHIM.OTHE]Chemical Sciences/Other, Food Science
Abstract: International audience; The gelatin used for the hard capsules manufacturing must meet strict dissolution specification to ensure the delivery of drugs at right time in the digestive tract. However, the environment of production and storage time affect the quality of gelatin dissolution. This study aimed to identify the mechanisms underlying the geographical environment of production and aging impact on the gelatin dissolution rate. Gelatins from 3 different origins of production (A, B & C), whose dissolution rate had been previously characterized, were analyzed by Raman microspectroscopy before and after aging. The principal component analysis (PCA) clearly separated the aged gelatins from non-aged ones. The spectra interpretation suggested the denaturation of gelatin triple-helices. In addition, the formation of cross-links such as dityrosine, glucosyl-galactosylhydroxylysinonorleucine and proteoglycan-like sugar adducts was strongly suspected. Whatever the gelatin aging state, PCA systematically separated the B-gelatins from A and C-gelatins. Pentosidine cross-link was likely to vary depending on the production origin. Finally, the quality of dissolution was discriminated for aged gelatins of A-origin: the non-compliant gelatins exhibited higher lipid content than the compliant ones.
Published: 2018
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8. Study of the pseudo-polyrotaxane architecture as a route for mild surface functionalization by click-chemistry of poly(?-caprolactone)-based electrospun fibers

Author: Guy Schlatter, Anne Hébraud, Luc Avérous, Sébastien Gallet, Murielle Oster, Christophe Fajolles, Rachid Baati, Cédric Gaillard, Eric Pollet, Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Laboratoire Interdisciplinaire sur l'Organisation Nanométrique et Supramoléculaire (LIONS), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), French Agence Nationale de la Recherche (ANR), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: chemistry.chemical_classification, Bioconjugation, Materials science, Cyclodextrin, Biomedical Engineering, technology, industry, and agriculture, 02 engineering and technology, General Chemistry, General Medicine, [CHIM.MATE]Chemical Sciences/Material chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Nanofiber, Polycaprolactone, Polymer chemistry, Click chemistry, Surface modification, General Materials Science, Fiber, 0210 nano-technology, Caprolactone
Abstract: International audience; Polycaprolactone (PCL) electrospun fibers are widely developed for biomedical applications. However, their hydrophobicity and passivity towards cell growth is an important limitation. An original method to functionalize PCL nanofibers, making them reactive for bioconjugation of proteins or other molecules of interests in water under mild conditions, is here reported. This method involves the preparation of pseudo-polyrotaxanes (pPR) of cyclodextrin (CD) and PCL. Core:shell PCL:pPR fibers were then prepared by coaxial electrospinning in order to bring available reactive hydroxyl groups from the CD, at the fiber surface. Different pPRs architectures (star, miktoarm and block-copolymer-like) were synthesized to study the effect of the pPR structure on the fiber morphology and surface reactivity by grafting fluorescein isothiocyanate (FITC). Finally, bicyclononyne groups were grafted onto the star-pPR based fibers allowing the conjugation of a fluorescent dye by click-chemistry in water without any copper catalyst proving the potential of the method for the biofunctionalization of PCL-based fibers.
Published: 2017
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9. Triazine-functionalized chitosan-encapsulated superparamagnetic nanoparticles as reusable and robust nanocarrier for glucoamylase immobilization

Author: Mahkameh Amirbandeh, Cédric Gaillard, Asieh Soozanipour, Asghar Taheri-Kafrani, University of Isfahan, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), and Research Councils of University of Isfahan
Subjects: Environmental Engineering, Immobilized enzyme, Biomedical Engineering, Bioengineering, 02 engineering and technology, 01 natural sciences, Catalysis, Chitosan, chemistry.chemical_compound, Immobilization, [SDV.IDA]Life Sciences [q-bio]/Food engineering, Organic chemistry, Reactivity (chemistry), [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Triazine, Reusability, Nanocomposite, Cyanuric chloride, biology, 010405 organic chemistry, Aspergillus niger, 021001 nanoscience & nanotechnology, biology.organism_classification, 0104 chemical sciences, Chemical engineering, chemistry, Glucoamylase, Magnetic nanoparticles, Nanocarriers, 0210 nano-technology, Biotechnology
Abstract: Aspergillus niger glucoamylase (GLA) was covalently immobilized on 1,3,5-triazine-functionalized chitosan coated superparamagnetic nanoparticles (MNPCh-CC). The morphology, structure and properties of functionalized nanocomposite were investigated, as well as GLA immobilization process, through different analytical tools. Different experimental parameters such as optimum temperature, pH, reaction time and enzyme concentration were studied for free and immobilized enzyme. The GLA immobilized on nanocarrier exhibited excellent catalytic activity at pH 4.5 and 60 °C. Notably, the immobilized GLA showed quite impressive stability, even after 10 reaction cycles, it could still retain about 70% of the initial activity. The results showed that immobilization process couldn’t significantly inhibit enzyme-substrate interaction and subsequently retained its effective catalytic activity. The substantial improvement of reactivity, reusability, and stability of this biocatalyst system may confer it a wider range of applications in industrial processes.
Published: 2017
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10. Mechanical properties of membranes composed of gel-phase or fluid-phase phospholipids probed on liposomes by atomic force spectroscopy

Author: Nicolas Delorme, Cédric Gaillard, Christelle Lopez, Franck Artzner, Oumaima Et-Thakafy, Fanny Guyomarc'H, Cristelle Mériadec, Science et Technologie du Lait et de l'Oeuf (STLO), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Institut des Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), The Asylum Research MFP3D-BIO atomic force microscope was funded by the European Union (FEDER), the French Ministry of Education and Research, INRA, Conseil Général 35 and Rennes Métropole. The doctoral fellowship of author Et-Thakafy was funded by INRA CEPIA and Région Bretagne under the grant ARED 8806., Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS), and Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS)
Subjects: phospholipide, x ray, rayon x, Lipid Bilayers, Analytical chemistry, diffraction, 02 engineering and technology, Microscopy, Atomic Force, 010402 general chemistry, vésicule phospholipidique, 01 natural sciences, Adsorption, membrane lipidique, lipid, Microscopy, Electrochemistry, General Materials Science, Lipid bilayer, Phospholipids, Spectroscopy, lipide, Mechanical Phenomena, [PHYS]Physics [physics], Liposome, Chemistry, Spectrum Analysis, Force spectroscopy, technology, industry, and agriculture, Surfaces and Interfaces, Penetration (firestop), [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 0104 chemical sciences, diffraction électronique, Membrane, [CHIM.POLY]Chemical Sciences/Polymers, Electron diffraction, Liposomes, liposome, Phosphatidylcholines, electron diffraction, lipids (amino acids, peptides, and proteins), spectroscopie à force atomique, 0210 nano-technology
Abstract: International audience; In many liposome applications, the nanomechanical properties of the membrane envelope are essential to ensure, e.g., physical stability, protection, or penetration into tissues. Of all factors, the lipid composition and its phase behavior are susceptible to tune the mechanical properties of membranes. To investigate this, small unilamellar vesicles (SUV; diameter < 200 nm), referred to as liposomes, were produced using either unsaturated 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) or saturated 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) in aqueous buffer at pH 6.7. The respective melting temperatures of these phospholipids were −20 and 41 °C. X-ray diffraction analysis confirmed that at 20 °C DOPC was in the fluid phase and DPPC was in the gel phase. After adsorption of the liposomes onto flat silicon substrates, atomic force microscopy (AFM) was used to image and probe the mechanical properties of the liposome membrane. The resulting force–distance curves were treated using an analytical model based on the shell theory to yield the Young’s modulus (E) and the bending rigidity (kC) of the curved membranes. The mechanical investigation showed that DPPC membranes were much stiffer (E = 116 ± 45 MPa) than those of DOPC (E = 13 ± 9 MPa) at 20 °C. The study demonstrates that the employed methodology allows discrimination of the respective properties of gel- or fluid-phase membranes when in the shape of liposomes. It opens perspectives to map the mechanical properties of liposomes containing both fluid and gel phases or of biological systems.
Published: 2017
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11. Self-Assembling Behavior of Glycerol Monoundecenoate in Water

Author: Cédric Gaillard, Frédéric Nallet, Romain Valentin, Zéphirin Mouloungui, Laurence Navailles, Gildas Nyame Mendendy Boussambe, Jean-François Fabre, Chimie Agro-Industrielle (CAI), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Ecole nationale supérieure des ingénieurs en arts chimiques et technologiques-Institut National de la Recherche Agronomique (INRA), Centre de Recherche Paul Pascal (CRPP), Université de Bordeaux (UB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), French government and the Midi-Pyrénées Region Fond Unique Interministériel (FUI) and the CEPIA Department of INRA for support of the ANS program., Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National de la Recherche Agronomique - INRA (FRANCE), Université de Bordeaux (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Institut National de la Recherche Agronomique (INRA)-Ecole nationale supérieure des ingénieurs en arts chimiques et technologiques-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Laboratoire de Chimie Agro-Industrielle (LCA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Toulouse, and Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Glycerol, [SDV.SA]Life Sciences [q-bio]/Agricultural sciences, Lamellar phases, 02 engineering and technology, Water retention, 010402 general chemistry, 01 natural sciences, Surface tension, Fatty Acids, Monounsaturated, chemistry.chemical_compound, Differential scanning calorimetry, [CHIM.GENI]Chemical Sciences/Chemical engineering, Electrochemistry, medicine, Génie chimique, General Materials Science, Cryogenic transmission electron microscopy, Vesicles, Spectroscopy, Polarized light microscopy, Molecular Structure, Small-angle X-ray scattering, Water, Surfaces and Interfaces, Self-assembly, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 0104 chemical sciences, Crystallography, chemistry, Chemical engineering, Transmission electron microscopy, Undecylenic acid, Surface tension experiments, 0210 nano-technology, Sciences agricoles, medicine.drug
Abstract: International audience; The self-assembling properties of glycerol esters in water are well known. Still, few data on glycerol monoesters of undecylenic acid are available. The aim of this study was to highlight the behavior of glycerol monoundecenoate (GM-C11:1) in different diluted and concentrated states. Its self-assembling properties in water and upon solid inorganic surfaces were investigated in the diluted state using surface tension experiments, atomic force microscopy, and cryogenic transmission electron microscopy studies. In the concentrated state, the gelling properties in the presence of water were investigated using polarized light microscopy, differential scanning calorimetry (DSC), and small-angle X-ray scattering (SAXS) experiments. GM-C11:1 at 100 mg/L self-assembles at the liquid/air interfaces as aggregates of approximately 20 nm in diameter, organized into concentric forms. These aggregates are spherical globules composed of several molecules of GM-C11:1. At higher concentrations (1000 and 104 mg/L), GM-C11:1 is able to uniformly coat liquid/air and liquid/solid interfaces. In bulk, GM-C11:1 forms spontaneously aggregates and vesicles. In a more concentrated state, GM-C11:1 assembles into lamellar Lβ and Lα forms in water. By cross-referencing SAXS and DSC findings, we were able to distinguish between interlamellar water molecules strongly bound to GM-C11:1 and other molecules remaining unbound and considered to be “mobile” water. The percentage of water strongly bound was proportional to the percentage of GM-C11:1 in the system. In this case, GM-C11:1 appears to be an effective molecule for surface treatments for which water retention is important.
Published: 2017
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12. Synthesis of Flower-Like Polybutadiene

Author: Erwan Nicol, Stéphane Carlotti, Cédric Gaillard, René-Ponce Nzé, Suwat Kaewbuddee, Institut des Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Bretagne Loire (UBL), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Laboratoire de Chimie des Polymères Organiques (LCPO), Centre National de la Recherche Scientifique (CNRS)-Institut Polytechnique de Bordeaux-Ecole Nationale Supérieure de Chimie, de Biologie et de Physique (ENSCBP)-Université de Bordeaux (UB)-Institut de Chimie du CNRS (INC), Team 1 LCPO : Polymerization Catalyses & Engineering, Centre National de la Recherche Scientifique (CNRS)-Institut Polytechnique de Bordeaux-Ecole Nationale Supérieure de Chimie, de Biologie et de Physique (ENSCBP)-Université de Bordeaux (UB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Polytechnique de Bordeaux-Ecole Nationale Supérieure de Chimie, de Biologie et de Physique (ENSCBP)-Université de Bordeaux (UB)-Institut de Chimie du CNRS (INC), Region des Pays de la Loire (Nanofleurs Project), Institut des Molécules et Matériaux du Mans, Le Mans Université (UM), Université de Bordeaux (UB)-Ecole Nationale Supérieure de Chimie, de Biologie et de Physique (ENSCBP)-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS), TEAM 1 LCPO, and Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS)
Subjects: Polymers and Plastics, [SDV]Life Sciences [q-bio], block copolymer, 02 engineering and technology, SARA-ATRP, 010402 general chemistry, 01 natural sciences, Micelle, anionic polymerization, Polybutadiene, Dynamic light scattering, Polymer chemistry, Materials Chemistry, Copolymer, Physical and Theoretical Chemistry, Reversible-deactivation radical polymerization, chemistry.chemical_classification, Chemistry, Organic Chemistry, Polymer, self-assembly, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 0104 chemical sciences, photo-crosslinking, Anionic addition polymerization, Living polymerization, 0210 nano-technology
Abstract: Synthesis of complex macromolecular architectures exhibiting no chain ends such as flower-like polymers is still of interest in the aim of investigating their physicochemical properties. For this purpose, poly(3,4-dimethyl maleic imidoethyl acrylate)-block-polybutadiene-block-poly(3,4-dimethyl maleic imidoethyl acrylate) triblock copolymer is synthesized in a convergent manner using a combination of living polymerization (anionic polymerization), reversible deactivation radical polymerization, and click chemistry. This copolymer is self-assembled in a selective solvent (heptane/THF mixture) of the polybutadiene block leading to the formation of flower-like micelles in thermodynamic equilibrium in dilute solution. These resulting transient architectures are fixed by covalently crosslinking the micelles core by inducing [2+2] cyclodimerization of the 3,4-dimethyl maleic imidoethyl groups borne by the short solvophobic blocks under UV irradiation. Single flowers are isolated from residual non-crosslinked chains by semipreparative size exclusion chromatography (SEC) and characterized by H-1 NMR, SEC, dynamic light scattering (DLS), and transmission electron microscopy (TEM).
Published: 2017
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13. Structural, Viscoelastic, and Electrochemical Characteristics of Self-Assembled Amphiphilic Comblike Copolymers in Aqueous Solutions

Author: Claude Deslouis, Cédric Gaillard, Boualem Saidani, Lila Chaal, Lazhar Benyahia, Malika Talantikite, Kahina Aoudia, Christophe Chassenieux, Institut des Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Electrochimie, Corrosion et de Valorisation Energétique (LECVE), Université A. Mira, Laboratoire Interfaces et Systèmes Electrochimiques (LISE), Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Electrochimie, Corrosion et de Valorisation Energétique [Université de Béjaïa] (LECVE), Université Abderrahmane Mira [Béjaïa], Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), 'TASSILI' program [13MDU 893], and University of Bejaia
Subjects: Materials science, 02 engineering and technology, 01 natural sciences, Micelle, 010305 fluids & plasmas, chemistry.chemical_compound, Electrochemical characteristic, 0103 physical sciences, Amphiphile, Polymer chemistry, Materials Chemistry, [CHIM]Chemical Sciences, Physical and Theoretical Chemistry, Rotating disk electrode, chemistry.chemical_classification, Viscoelastic, Aqueous solution, Polymer, Polyelectrolyte, 021001 nanoscience & nanotechnology, Surfaces, Coatings and Films, Dication, Chemical engineering, chemistry, Polystyrene, 0210 nano-technology, [CHIM.OTHE]Chemical Sciences/Other
Abstract: International audience; Self-assembly in aqueous solutions of an amphiphilic comblike polyelectrolyte (80C12) that consists of a polystyrene (PS) backbone onto which quaternary ammonium pendant moieties have been grafted has been investigated by light scattering and cryo-transmission electron microscopy measurements in the presence of KCl and methylviologen dication (MV2+) under conditions mimicking those for electrochemical measurements. Polymer chains self-assemble within branched cylindrical micelles that display viscoelastic properties, characterized by a relaxation time of 4 s. To tune this time, 80C12 was mixed with a polyoxyethylene nonionic surfactant (Brij C12E10). Relatively increasing the amount of the latter leads to a decrease in the relaxation time of the 80C12 solution. Correlatively, electrochemical experiments with a rotating disk electrode show a transition of the mass transport rate, which deviates from the classical Newtonian behavior in the same velocity domain. This result generalizes what has been already observed with solutions of linear polymers of high molecular weight and wormlike micelles based on surfactants subjected to elongational deformations. Moreover, the critical times derived from rheological and electrochemical experiments display the same trend.
Published: 2017
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14. Fast and effective quantum-dots encapsulation and protection in PEO based photo-cross-linked micelles

Author: Erwan Nicol, Benoit Dubertret, Christophe Chassenieux, Khalid Ferji, Cédric Gaillard, Ines Hamouda, Brice Nadal, Institut des Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), NEXDOT, Laboratoire de Physique et d'Etude des Matériaux (UMR 8213) (LPEM), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), project Nanofleurs, Centre National de la Recherche Scientifique (CNRS)-Le Mans Université (UM), Laboratoire de Physique et d'Etude des Matériaux (LPEM), Centre National de la Recherche Scientifique (CNRS)-ESPCI ParisTech-Université Pierre et Marie Curie - Paris 6 (UPMC), laboratoire d'optique physique, and Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Block copolymer, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Micelle, Biomaterials, Colloid, chemistry.chemical_compound, Colloid and Surface Chemistry, Amphiphile, Polymer chemistry, Copolymer, [CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS, Acrylate, Ethylene oxide, Photo-cross-linking, technology, industry, and agriculture, Quantum dot, 021001 nanoscience & nanotechnology, equipment and supplies, Fluorescence photoenhancement, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, Chemical engineering, Emulsion, Encapsulation, 0210 nano-technology
Abstract: International audience; Cadmium-based quantum dots (QDs) were easily, quickly and efficiently transferred from an organic medium to water without modification of their surface chemistry by the simple emulsion/solvent evaporation technique using micelles of amphiphilic diblock copolymers based on poly(ethylene oxide) and poly(2-methacryloyloxyethyl acrylate) (PEO-b-PMEA) as hosts. The resulting hybrid micelles were stabilized very rapidly by photo-cross-linking the hydrophobic core around the QDs. The encapsulation and photo-cross-linking process were shown to barely affect the photoluminescence properties. Grafting a short octyl chain at the end of the hydrophobic block enhanced both the colloidal stability of the QDs dispersed in water and prevented the quenching of their fluorescence by copper ions. Grafting a longer hexadecyl chain at the end of the PMEA block decreased the efficiency of the corona cross-linking and led to poorer stabilization and protection.
Published: 2016
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15. On the interaction of alginate-based core-shell nanocarriers with keratinocytes in vitro

Author: Lynda Miloudi, Igor Chourpa, Cédric Gaillard, Emilie Munnier, Imane Eddaoudi, Martin Soucé, Hoang Truc Phuong Nguyen, Emilie Allard-Vannier, Nanomédicaments et Nanosondes, EA 6295 (NMNS), Université de Tours (UT), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), NANO'derm project Region (Centre Val de Loire Bioeurope (Solabia Group), Carlina Technologies and Spincontrol, for financial support), and Université de Tours
Subjects: Keratinocytes, Calcium alginate, 02 engineering and technology, 01 natural sciences, chemistry.chemical_compound, Colloid and Surface Chemistry, Glucuronic Acid, Fluorescence Resonance Energy Transfer, Internalization, media_common, Drug Carriers, Hexuronic Acids, Surfaces and Interfaces, General Medicine, Carbocyanines, 021001 nanoscience & nanotechnology, Endocytosis, medicine.anatomical_structure, Drug delivery, 0210 nano-technology, Drug carrier, Keratinocyte, Hydrophobic and Hydrophilic Interactions, Core-shell nanocarrier, Biotechnology, Alginates, Cell Survival, Drug Compounding, media_common.quotation_subject, Nanotechnology, Caveolae, 010402 general chemistry, Cell Line, Microscopy, Electron, Transmission, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, medicine, Humans, Particle Size, Physical and Theoretical Chemistry, [SDV.IB.BIO]Life Sciences [q-bio]/Bioengineering/Biomaterials, Fluorescent Dyes, Alginate, Förster resonance energy transfer (FRET), 0104 chemical sciences, Drug Liberation, Kinetics, Förster resonance energy transfer, [SDV.SP.PG]Life Sciences [q-bio]/Pharmaceutical sciences/Galenic pharmacology, chemistry, Biophysics, Nanoparticles, Nanocarriers, [SDV.MHEP.DERM]Life Sciences [q-bio]/Human health and pathology/Dermatology
Abstract: International audience; Calcium alginate nanocarriers (CaANCs) were developed as a potential tool for delivery of hydrophobic active molecules such as pharmaceutical and cosmetic active ingredients. In this study, we focused on interactions between CaANCs and keratinocytes in culture and examined toxicity, internalization and drug release. Prior to cellular interactions, cryogenic transmission electron microscopy images showed that CaANCs appear as regular, spherical and dense particles, giving evidence of the surface gelation of CaANCs. Their size, around 200 nm, was stable under tested conditions (temperature, culture media, presence of serum and presence of encapsulated dye), and their toxicity on keratinocytes was very low. Flow cytometry assays showed that CaANCs are internalized into keratinocytes by endocytosis with a predominant implication of the caveolae-mediated route. Förster resonance energy transfer (FRET) demonstrated that after a 2 h contact, the release of CaANC contents in the cytoplasm of keratinocytes was almost complete. The endocytosis of CaANCs by a lysosome-free pathway, and the rapid release of their contents inside keratinocytes, will allow vectorized molecules to fully exhibit their pharmacological or cosmetic activity.
Published: 2016
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16. Simple Engineering of Polymer-Nanoparticle Hybrid Nanocapsules

Author: Flavien Sciortino, Cédric Gaillard, Gérald Casterou, Fabienne Gauffre, Myrtil L. Kahn, Marie-Bérengère Troadec, Soizic Chevance, Pierre-Antoine Eliat, Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes-Centre National de la Recherche Scientifique (CNRS), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Plate-forme Rennaise d'Imagerie et Spectroscopie Structurale et Métabolique (PRISM), Institut National de la Recherche Agronomique (INRA)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), Institut de Génétique et Développement de Rennes (IGDR), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), BIOSIT-University of Rennes 1, CNRS UMS, Inserm US, Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Rennes-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique )-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique )-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique )-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), and Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique )
Subjects: Materials science, water, Energy Engineering and Power Technology, Nanoparticle, Nanotechnology, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Nanocapsules, Biomaterials, chemistry.chemical_compound, Materials Chemistry, copolymers, [CHIM]Chemical Sciences, chemistry.chemical_classification, vesicles, Renewable Energy, Sustainability and the Environment, [CHIM.MATE]Chemical Sciences/Material chemistry, Polymer, 021001 nanoscience & nanotechnology, 0104 chemical sciences, stabilization, agents, Solvent, solvents, mixtures, chemistry, Colloidal gold, Polymersome, Self-assembly, iron-oxide nanoparticles, 0210 nano-technology, Iron oxide nanoparticles, supramolecular structures, nanobubbles
Abstract: International audience; A general method to generate hybrid hollow capsules is reported. The process is based on the stabilization of solvent droplets by nanoparticles, in macroscopically miscible mixtures of tetrahydrofuran (THF) and water. After addition of a crosslinking polymer and removal of the solvent core, capsules of diameter ca 100 nm are obtained. This novel strategy does not require the use of block copolymers. In contrast, most methods reporting the formation of hybrid nanocapsules incorporate nanoparticles into block-copolymer polymersomes or use nanoparticles tethered with block-copolymers. The nanocapsules were characterized using a full set of techniques including nanoparticle tracking analysis, electron microscopy and liquid phase atomic force microscopy. Our results show that the vesicular shape of the nanocapsules is templated by the liquid droplets. Nanocapsules were prepared from quantum dots, gold nanoparticles, superparamagnetic iron oxide nanoparticles and mixtures of particles. The entrapment of a fluorescent dye was also demonstrated. Thus, nanocapsules with dual properties (e.g., magnetic and fluorescent) are easily obtained. Interestingly, the magnetic nanocapsules enable magnetic resonance imaging contrast enhancement of tumors in vivo.
Published: 2016
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17. Electrostatically driven modulation of the reinforcement of agarose hydrogels by cellulose nanowhiskers

Author: Cédric Gaillard, Kévin Jacques Le Goff, Thierry Aubry, Catherine Garnier, Université de Bretagne Occidentale, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), and Region Bretagne
Subjects: Materials science, Polymers and Plastics, polysaccharides, Nanoparticle, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, chemistry.chemical_compound, nanowires and nanocrystals, Polymer chemistry, Materials Chemistry, Surface charge, Cellulose, structure-property relations, General Chemistry, 021001 nanoscience & nanotechnology, gels, 0104 chemical sciences, Surfaces, Coatings and Films, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, Chemical engineering, Transmission electron microscopy, Self-healing hydrogels, Volume fraction, Agarose, nanoparticles, rheology, 0210 nano-technology, Dispersion (chemistry)
Abstract: The modulation of the reinforcement effect brought by the addition of tunicate cellulose nanowhiskers with different surface charge densities to an agarose hydrogel matrix has been studied using linear viscoelastic measurements. The cellulose nanowhiskers were characterized using transmission electron microscopy, and their surface charge was determined by a titration method. The results show that increasing the charge at the surface of nanowhiskers tends to enhance the reinforcement effect, because of a better dispersion of nanowhiskers. However, the results also suggest the existence of an optimum surface charge, corresponding to a maximum reinforcement effect at a given volume fraction. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43063.
Published: 2016
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18. Inside Cover: Simple Engineering of Polymer-Nanoparticle Hybrid Nanocapsules (ChemNanoMat 8/2016)

Author: Cédric Gaillard, Marie-Bérengère Troadec, Myrtil L. Kahn, Soizic Chevance, Pierre-Antoine Eliat, Gérald Casterou, Flavien Sciortino, Fabienne Gauffre, Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Plate-forme Rennaise d'Imagerie et Spectroscopie Structurale et Métabolique (PRISM), Institut National de la Recherche Agronomique (INRA)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), Institut de Génétique et Développement de Rennes (IGDR), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Université de Rennes (UR)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Rennes-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: chemistry.chemical_classification, Materials science, Renewable Energy, Sustainability and the Environment, Low dose, Polymer nanoparticle, Energy Engineering and Power Technology, Nanoparticle, Nanotechnology, Polymer, Nanocapsules, Biomaterials, Metal, chemistry.chemical_compound, chemistry, visual_art, Materials Chemistry, visual_art.visual_art_medium, [CHIM]Chemical Sciences, Self-assembly, Iron oxide nanoparticles
Abstract: International audience; In the Communication featured on the Inside Cover, the authors use the unsuspected presence of nanodroplets (∼100 nm) in water/THF mixtures to template the formation of hybrid nanocapsules, “hybridosomes”, with a shell consisting of a crosslinked network of particles and polymers. Magnetic hybridosomes prepared from iron oxide nanoparticles enhance MRI contrast, enabling the imaging of tumor areas at low dose. This universal process can be applied to various types of inorganic nanoparticles (metallic, semi-conducting, etc.) and to mixtures, opening the way to highly multifunctional nanocapsules. More information can be found in the Communication by M. L. Kahn, F. Gauffre et al. on page 796 in Issue 8, 2016 (DOI: 10.1002/cnma.201600155).
Published: 2016
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19. Transition from vitreous to floury endosperm in maize (Zea mays L.) kernels is related to protein and starch gradients

Author: Laurent Linossier, Cédric Gaillard, Caroline Delluc, Bénédicte Bakan, Sylvie Brunet, Didier Marion, Mathieu Gayral, Khalil Elmorjani, Marie-Hélène Morel, Michèle Dalgalarrondo, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Groupe Limagrain, Limagrain Cereales Ingredients, Ingénierie des Agro-polymères et Technologies Émergentes (UMR IATE), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université Montpellier 2 - Sciences et Techniques (UM2)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Fond unique interministériel FUI (GranoFlakes, F1204004C), Limagrain Europe, and Fond unique interministeriel (FUI GranoFlakes) : F1204004C.
Subjects: 0106 biological sciences, genetic structures, Starch, développement de l'endosperme, Starch channels, 01 natural sciences, Biochemistry, teneur en amylose, Endosperm, Protein content, zea mays, chemistry.chemical_compound, Zein gradient, 0404 agricultural biotechnology, Amylose, [SDV.IDA]Life Sciences [q-bio]/Food engineering, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, Vitreousness, flint maize, 2. Zero hunger, endosperme, indian corn, maize starch, digestive, oral, and skin physiology, A protein, food and beverages, 04 agricultural and veterinary sciences, microspectroscopie, Maize endosperm, 040401 food science, maïs vitreux, Zea mays, eye diseases, Raman microspectroscopy, chemistry, Biophysics, amidon de mais, Starch granule, sense organs, seed albumins, 010606 plant biology & botany, Food Science
Abstract: International audience; Relationships between kernel vitreousness and proteins and starch partitioning to the floury and vitreous regions of the endosperm were monitored in a set of 13 maize inbred lines. Decrease of protein contents from the vitreous to the floury endosperms were mainly assigned to a-zeins. Using Raman microspectroscopy, we observed a protein gradient from the periphery to the center of endosperms that well fitted with the inverse relationships between vitreousness and protein content of the vitreous and floury regions. In addition, Raman microspectroscopy highlighted an increase of starch crystallinity from the periphery to the center of the maize endosperms. This agrees with the higher amylose and associated lipid contents within starches of vitreous than in those of floury endosperms. Finally, starch granules from vitreous regions displayed more channels than the floury ones. These channels contain proteins that might favor adhesion of proteins to starch granules or granule granule contacts to form the close packing of the vitreous endosperm. Therefore transition from vitreous to floury endosperm is at least the result of both protein and starch gradients. These gradients are probably associated with metabolic gradients that have been observed during endosperm development. (C) 2016 Elsevier Ltd. All rights reserved.
Published: 2016
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20. Sequestration of bovine seminal plasma proteins by different assemblies of phosphatidylcholine: A new technical approach

Author: Daniel Tainturier, Elisabeth David-Briand, Marc Anton, J. van Leeuwen-Ibarrola, Cédric Gaillard, Eric Schmitt, S. Desherces, Marie-Hélène Ropers, L. Amirat-Briand, D. Bencharif, J. Le Guillou, Ecole Nationale Vétérinaire, Agroalimentaire et de l'alimentation Nantes-Atlantique (ONIRIS), IMV Technologies, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), and Institut National de la Recherche Agronomique (INRA)
Subjects: Male, 0301 basic medicine, Seminal Plasma Proteins, Lipid Bilayers, chemistry.chemical_compound, 0302 clinical medicine, Colloid and Surface Chemistry, fluids and secretions, Lipid bilayer, Liposome, 030219 obstetrics & reproductive medicine, Interfacial properties, Bull spermatozoa, Surfaces and Interfaces, General Medicine, Egg Yolk, Spermatozoa, Lipoproteins, LDL, Biochemistry, Low-density lipoprotein, Phosphatidylcholines, Thermodynamics, Female, lipids (amino acids, peptides, and proteins), Biotechnology, Surface Properties, Membrane lipids, Phospholipid, Biology, LDL, Membrane Lipids, 03 medical and health sciences, Microscopy, Electron, Transmission, stomatognathic system, Semen, Capacitation, Phosphatidylcholine, Animals, Physical and Theoretical Chemistry, Cryopreservation, Cryoelectron Microscopy, Monolayer, Membranes, Artificial, 030104 developmental biology, chemistry, Liposomes, Cattle, [CHIM.OTHE]Chemical Sciences/Other, Chickens, Semen Preservation
Abstract: International audience; Binder of SPerm (BSP) proteins, the main proteins from bovine seminal plasma, are known to partially intercalate into the outer leaflet of the spermatozoa membrane and bind to choline-containing lipids being present therein. This insertion generates a negative effect on semen quality after cryopreservation by inducing an early-stage capacitation of spermatozoa. The assumption of surface properties exhibited by BSP proteins was checked by tensiometry measurements: BSP proteins are highly surface active. This suggests that BSP proteins can reach the interface covered by phospholipids not only by interactions between one and each other but also due to their own surface activity. The insertion of BSP proteins into the lipid domains outer leaflet of spermatozoa was reproduced on a biomimetic system such as Langmuir monolayers. The insertion of BSP proteins can be performed in the compressible fluid domains which contain choline-bearing lipids. Monolayer films were used as well to study the complexation of BSP proteins by two phospholipid assemblies: low density lipoprotein (LDLs) from egg yolk or liposomes produced from egg phospholipids. Irrespective of the phospholipid structure (lipoprotein or liposome), BSP was hindered to alter the structure of the membrane. Only the overall ratio BSP proteins:phosphatidylcholine was important. The difference between the two sequestering agents lies on their surface properties: LDL have a strong tendency to merge with the outer layer whereas liposomes mainly remain in the bulk on the same time scale.
Published: 2016
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21. Smart Nonaqueous Foams from Lipid-Based Oleogel

Author: Anne-Laure Fameau, Cédric Gaillard, Arnaud Saint-Jalmes, Orlin D. Velev, Audrey Arnould, Stephanie Lam, Unité de Recherches Biopolymères, Interactions, Assemblages, Institut National de la Recherche Agronomique (INRA), department of chemical and biochemical engineering, North Carolina State University [Raleigh] (NC State), University of North Carolina System (UNC)-University of North Carolina System (UNC), UR1268 Biopolymeres Interactions Assemblages, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique, W911NF-15-1-0115, Army Research Office, MP 1106, European Cooperation in Science and Technology, DMR-1121107, Division of Materials Research, Région Pays de la Loire, INRA (UR 1268), and Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, food.ingredient, Surface Properties, Fatty alcohol, Nanotechnology, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, law.invention, Crystal, chemistry.chemical_compound, Adsorption, food, Pulmonary surfactant, law, Electrochemistry, Plant Oils, Sunflower Oil, General Materials Science, cardiovascular diseases, Organic Chemicals, Particle Size, Crystallization, Spectroscopy, Aqueous solution, Sunflower oil, Temperature, Foams, Surfaces and Interfaces, Interface, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Lipids, 0104 chemical sciences, chemistry, Chemical engineering, lipids (amino acids, peptides, and proteins), Particle size, Fatty Alcohols, 0210 nano-technology, [PHYS.COND.CM-SCM]Physics [physics]/Condensed Matter [cond-mat]/Soft Condensed Matter [cond-mat.soft]
Abstract: COST [MP 1106]; INRA; Region Pays de la Loire; U.S. Army Research Office [W911NF-15-1-0115]; NSF Research Triangle MRSEC on Programmable Soft Matter [DMR-1121107]; International audience; Oil foams are composed of gas bubbles dispersedin an oil phase. These systems are scarcely studied despite theirgreat potential in diverse fields such as the food and cosmeticindustries. Contrary to aqueous foams, the production of oilfoams is difficult to achieve due to the inefficiency of surfactantadsorption at oil−air interfaces. Herein, we report a simple way toproduce oil foams from oleogels, whose liquid phase is a mixtureof sunflower oil and fatty alcohols. The temperature at which theoleogel formed was found to depend on both fatty alcohol chainlength and concentration. The air bubbles in the oleogel foamwere stabilized by fatty alcohol crystals. Below the meltingtemperature of the crystals, oleogel foams were stable for months.Upon heating, these ultrastable foams collapsed within a few minutes due to the melting of the crystal particles. The transitionbetween crystal formation and melting was reversible, leading to thermoresponsive nonaqueous foams. The reversible switchingbetween ultrastable and unstable foam depended solely on the temperature of the system. We demonstrate that these oleogelfoams can be made to be photoresponsive by using internal heat sources such as carbon black particles, which can absorb UVlight and dissipate the absorbed energy as heat. This simple approach for the formulation of responsive oil foams could be easilyextended to other oleogel systems and could find a broad range of applications due to the availability of the components in largequantities and at low cost.
Published: 2015
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22. Branched Wormlike Micelles Formed by Self-Assembled Comblike Amphiphilic Copolyelectrolytes

Author: Taco Nicolai, Fabien Dutertre, Christophe Chassenieux, Cédric Gaillard, Institut des Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), and Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: chemistry.chemical_classification, Materials science, Aqueous solution, Polymers and Plastics, Organic Chemistry, Polymer, Branching (polymer chemistry), Micelle, Inorganic Chemistry, chemistry.chemical_compound, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, Ionic strength, Polymer chemistry, Materials Chemistry, Side chain, lipids (amino acids, peptides, and proteins), Polystyrene, Alkyl, ComputingMilieux_MISCELLANEOUS
Abstract: International audience; The structure of the self-assemblies formed by amphiphilic comblike copolyelectrolytes dispersed in water has been investigated by scattering techniques (light and neutron) and by transmission electronic microscopy. The comblike polymers consisted of a polystyrene backbone grafted with a fixed amount of pendant N,N-dimethyl quaternary ammonium alkyl groups of various lengths ranging from C12 up to C18. In aqueous solution, the polymers self-assembled into small spherical aggregates at low concentrations and into cylindrical aggregates above a critical concentration with a diameter that increased with the length of the alkyl side chains. The length of the cylindrical aggregates increased with increasing concentration, and branching occurred at higher concentration, which induced gelation above a critical percolation concentration. Growth and branching were favored by increasing the ionic strength of the solution. The dynamics slowed down with decreasing temperature and increasing alkyl length, and the assemblies of polymers with C16 and C18 pendant chains were kinetically frozen at 20 degrees C.
Published: 2015
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23. Polymersomes from Amphiphilic Glycopolymers Containing Polymeric Liquid Crystal Grafts

Author: Min-Hui Li, Khalid Ferji, Cédric Gaillard, Erwan Nicol, Christophe Chassenieux, Jean-Luc Six, Jérôme Babin, Cécile Nouvel, Laboratoire de Chimie Physique Macromoléculaire (LCPM), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Institut des Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche de Chimie Paris (IRCP), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Ministère de la Culture (MC), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL), Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS), Ecole Nationale Supérieure de Chimie de Paris- Chimie ParisTech-PSL (ENSCP)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC), and Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Acrylate, Materials science, Polymers and Plastics, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Organic Chemistry, Diethylene glycol, Ether, Polymeric liquid crystal, Inorganic Chemistry, chemistry.chemical_compound, Dextran, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, Dynamic light scattering, Polymersome, Amphiphile, Polymer chemistry, Materials Chemistry, ComputingMilieux_MISCELLANEOUS
Abstract: International audience; For the first time, polymersomes were obtained by self-assembly in water of ampliiphilic grafted glycopolymers based on dextran polysaccharidic backbone and polymeric liquid crystal grafts (poly(diethylene glycol cholesteryl ether acrylate), PDEGCholA). After measuring the properties of these glycopolymers in term of surfactancy, the influence of their structural parameters on their self-assemblies once dispersed in water was investigated by static and dynamic light scattering and by cryogenic transmission electron microscopy (cryo-TEM). Based on the results, a proper design of Dex-g(N)-PDEGCholA(F) leads to hollow vesicular structure formulation known as polymersome.
Published: 2015
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24. Self-assembly of myristic acid in the presence of choline hydroxide: Effect of molar ratio and temperature

Author: Audrey Arnould, Cédric Gaillard, Liliana G. Santiago, Anne-Laure Fameau, Thomas Zemb, Adrián A. Perez, Marc Anton, Jean-Paul Douliez, Fabrice Cousin, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Grupo Biocoloides y nanotecnologías (GBN), Universidad Nacional del Litoral [Santa Fe] (UNL), Biologie du fruit et pathologie (BFP), Université Bordeaux Segalen - Bordeaux 2-Institut National de la Recherche Agronomique (INRA)-Université Sciences et Technologies - Bordeaux 1, Laboratoire Léon Brillouin (LLB - UMR 12), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay, Tri ionique par les Systèmes Moléculaires auto-assemblés (LTSM), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université Bordeaux Segalen - Bordeaux 2-Institut National de la Recherche Agronomique (INRA)-Université Sciences et Technologies - Bordeaux 1 (UB), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Molar ratio, Inorganic chemistry, Lipid Bilayers, Myristic acid, molar ratio, 02 engineering and technology, INGENIERÍAS Y TECNOLOGÍAS, Conductivity, 010402 general chemistry, 01 natural sciences, Micelle, Myristic Acid, catanionic, Phase Transition, Choline, Biomaterials, chemistry.chemical_compound, Colloid and Surface Chemistry, Differential scanning calorimetry, Counter-ion, [CHIM]Chemical Sciences, counter-ion, chemistry.chemical_classification, Ions, Nanotecnología, Temperature, Fatty acid, Self-assembly, self-assembly, 021001 nanoscience & nanotechnology, Nano-materiales, Small-angle neutron scattering, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, chemistry, Hydroxide, fatty acid, Counterion, 0210 nano-technology, Catanionic
Abstract: Salt-free catanionic systems based on fatty acids and cationic surfactants are known to exhibit a broad polymorphism by simply tuning the molar ratio between the two components. In the case of fatty acid combined with organic amino counter-ions, very few data are available on the phase behavior obtained as a function of the molar ratio between the counter-ion and the fatty acid. In this study, we investigated the choline hydroxide/myristic acid system as a function of the molar ratio, R= n choline hydroxide/n myristic acid, and the temperature. At molecular scale, the ionization state of myristic acid was determined as a function of R by coupling pH, conductivity and infra-red spectroscopy measurements. At microscopic scale, the self-assemblies were characterized by small angle neutron scattering and microscopy experiments.For R1, all the myristic acid molecules were under their ionized form and only spherical micelles were present in solution. As in the case of catanionic systems, our study highlights that both R and temperature are two key parameters to finely control the self-assembly structure formed by myristic acid in the presence of choline hydroxide. Fil: Arnould, Audrey. Institut National de la Recherche Agronomique; Francia Fil: Perez, Adrián Alejandro. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Gaillard, Cédric. Institut National de la Recherche Agronomique; Francia Fil: Douliez, Jean Paul. Institut National de la Recherche Agronomique; Francia Fil: Cousin, Fabrice. Centre National de la Recherche Scientifique; Francia Fil: Santiago, Liliana Gabriela. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Zemb, Thomas. Centre National de la Recherche Scientifique; Francia Fil: Anton, Marc. Institut National de la Recherche Agronomique; Francia Fil: Fameau, Anne Laure. Institut National de la Recherche Agronomique; Francia
Published: 2015
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25. Rheological study of reinforcement of agarose hydrogels by cellulose nanowhiskers

Author: Cédric Gaillard, Thierry Aubry, William Helbert, Catherine Garnier, Kévin Jacques Le Goff, ONERA - The French Aerospace Lab [Salon], ONERA, Marchés, Organisations, Institutions et Stratégies d'Acteurs (UMR MOISA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre International de Hautes Etudes Agronomiques Méditerranéennes - Institut Agronomique Méditerranéen de Montpellier (CIHEAM-IAMM), Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Centre National de la Recherche Scientifique (CNRS), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Laboratoire d'Ingénierie des Matériaux de Bretagne (LIMATB), Université de Bretagne Sud (UBS)-Institut Brestois du Numérique et des Mathématiques (IBNM), Université de Brest (UBO)-Université de Brest (UBO)-Université de Brest (UBO), Centre de Recherches sur les Macromolécules Végétales (CERMAV), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Institut Brestois du Numérique et des Mathématiques (IBNM), Université de Brest (UBO)-Université de Brest (UBO), Region Bretagne, Region Pays de Loire, GlycoOuest Network, Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre International de Hautes Etudes Agronomiques Méditerranéennes - Institut Agronomique Méditerranéen de Montpellier (CIHEAM-IAMM), and Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)
Subjects: Materials science, Polymers and Plastics, Nanoparticle, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Matrix (chemical analysis), chemistry.chemical_compound, Rheology, Materials Chemistry, Stress relaxation, Cellulose nanowhiskers, [CHIM]Chemical Sciences, Composite material, Cellulose, Agarose hydrogels, ComputingMilieux_MISCELLANEOUS, Organic Chemistry, Structure, Rheological behavior, 021001 nanoscience & nanotechnology, 0104 chemical sciences, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, Transmission electron microscopy, Self-healing hydrogels, Agarose, 0210 nano-technology
Abstract: International audience; The influence of the addition of tunicate cellulose nanowhiskers on the structural and rheological properties of an agarose hydrogel matrix has been studied, with the objective to design innovative green material, with good mechanical properties. The cellulose nanowhiskers were characterized using transmission electron microscopy, and their charge surface density was determined by a titration method. Oscillatory shear and stress relaxation tests were performed in order to characterize the rheological properties of the agarose matrix, and of the agarose hydrogels filled by nanowhiskers at volume fractions below 0.2%. The results show a significant reinforcement effect due to the addition of nanowhiskers, and suggest changes in the matrix network structure induced by the cellulose nanoparticles.
Published: 2015
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26. In vitro digestion of emulsions: high spatiotemporal resolution using synchrotron SAXS

Author: Sébastien Marze, Cédric Gaillard, Pierre Roblin, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), and Synchrotron SOLEIL
Subjects: Nanotechnology, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Models, Biological, law.invention, Digestion (alchemy), Spatio-Temporal Analysis, X-Ray Diffraction, law, Scattering, Small Angle, [SDV.IDA]Life Sciences [q-bio]/Food engineering, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Intestinal Mucosa, Triglycerides, Chemistry, Small-angle X-ray scattering, Vesicle, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, In vitro digestion, Synchrotron, 0104 chemical sciences, Kinetics, Chemical engineering, Emulsion, Digestion, Emulsions, Absorption (chemistry), 0210 nano-technology, Lipid digestion, Synchrotrons
Abstract: International audience; Although the biochemical processes of lipid digestion are well-known, the biophysical ones, responsible for the assembly of molecules into functional structures, lack studies resolving both time and space scales. About 35 years ago, the seminal microscopy study of Patton and Carey constituted a major advance to reach this goal. Nowadays, new perspectives arise from the availability of large facilities scattering techniques, able to monitor the dynamics of multi-scale assemblies with unprecedented resolutions. The present small angle X-ray scattering (SAXS) study focused on the roles of the emulsifier and triglyceride in the formation of lipid assemblies during emulsion digestion in vitro. By developing several interpretations of the data in the whole space range (qualitative, shape-dependent and shape-independent models), the characteristic size of the assemblies and their transition times were obtained, which depended on the triglyceride, but not on the emulsifier. The major assembly formed was found to be a spherical mixed micelle, but vesicle was also found to coexist throughout the digestion, although in a lower proportion. The quantitative determination of the sizes and proportions of these assemblies, as well as the evolution of these characteristics during digestion are precious information for nutritional sciences, as these assemblies are the vehicles of lipophilic nutrients and micronutrients towards their absorption site.
Published: 2015
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27. Anaerobic biodegradation of cellulose–xylan–lignin nanocomposites as model assemblies of lignocellulosic biomass

Author: Cédric Gaillard, Abdellatif Barakat, Hélène Carrère, Jean-Philippe Steyer, Laboratoire de Biotechnologie de l'Environnement [Narbonne] (LBE), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de la Recherche Agronomique (INRA), Ingénierie des Agro-polymères et Technologies Émergentes (UMR IATE), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Institut National de la Recherche Agronomique (INRA), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), and Institut National de la Recherche Agronomique (INRA)
Subjects: 0106 biological sciences, [SDV.SA]Life Sciences [q-bio]/Agricultural sciences, Environmental Engineering, animal structures, 020209 energy, Lignocellulosic biomass, Biomass, Biogas, 02 engineering and technology, macromolecular substances, Xylose, 7. Clean energy, 01 natural sciences, chemistry.chemical_compound, Lignocellulosic materials, 010608 biotechnology, Anaerobic digestion, 0202 electrical engineering, electronic engineering, information engineering, Lignin, Organic chemistry, Plant cell wall, Cellulose, Waste Management and Disposal, Model assemblies, Renewable Energy, Sustainability and the Environment, technology, industry, and agriculture, food and beverages, [CHIM.MATE]Chemical Sciences/Material chemistry, Accessibility, Xylan, carbohydrates (lipids), Monomer, chemistry
Abstract: International audience; In order to determine the parameters influencing lignocellulosic biomass biodegradability, binary and ternary model systems were constructed, consisting of cellulose nanowhiskers gel, xylan matrix derived from lignocellulosic plants and synthetic lignin. The adsorption of two xylan polymers with different arabinose/xylose ratios (Ara/Xyl) on the cellulose nanowhiskers resulted in the synthesis of nanocomposites each of different Ara/Xyl ratios and crystallinity indexes. Organized and associated cellulose–xylan–lignin nanocomposites were formed following the polymerization of guaı¨acyl (G) and syringyl (S) lignin monomers using a peroxidase/H2O2 system in cellulose nanowhiskers-xylan gel. The anaerobic digestion of cellulose nanowhiskers, xylans and cellulose–xylan nanocomposites indicated that the biomethane production depended strongly on the xylan Ara/Xyl ratio and on the cellulose crystallinity. However, the anaerobic digestion of cellulose–xylan–lignin nanocomposites showed that the digestion rate decreased significantly in the presence of lignin. Moreover, there was an even more considerable decrease in digestion rate in the presence of GS-type lignin compared to G-type lignin.
Published: 2014
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28. Self-assembly of fatty acids: from foams to protocell vesicles

Author: Cédric Gaillard, Jean-Paul Douliez, Biologie du fruit et pathologie (BFP), Université Sciences et Technologies - Bordeaux 1-Université Bordeaux Segalen - Bordeaux 2-Institut National de la Recherche Agronomique (INRA), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), and Institut National de la Recherche Agronomique (INRA)
Subjects: Protocell, Solid-state chemistry, [SDV.OT]Life Sciences [q-bio]/Other [q-bio.OT], Sodium, Potassium, Vesicle, Supramolecular chemistry, chemistry.chemical_element, General Chemistry, Krafft temperature, Catalysis, chemistry, Materials Chemistry, Organic chemistry, Self-assembly, [CHIM.OTHE]Chemical Sciences/Other
Abstract: International audience; Fatty acids are potentially versatile substitutes to phospholipids and synthetic surfactants in materials chemistry and biophysics. However, sodium (or potassium) salts of saturated long chain fatty acids (SLCFAs) are long known to be soluble at a high temperature but they crystallize below their Krafft point, hampering their use for multiple applications. Recent advances have shown that under particular experimental conditions, i.e., by using a 'good' counter-ion, SLCFAs can be dispersed in water into various supramolecular assemblies which opens up new fields of research and applications. Here, recent studies on the self-assembly of fatty acids are commented and some potential applications are proposed and discussed
Published: 2014
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29. Efficient in vitro gene therapy with PEG siRNA lipid nanocapsules for passive targeting strategy in melanoma

Author: Emilie André, Pauline Resnier, Nolwenn Lautram, Cédric Gaillard, Jean-Pierre Benoit, Catherine Passirani, Pierre LeQuinio, Guillaume Bastiat, Université d'Angers (UA), Micro et Nanomédecines Translationnelles (MINT), Université d'Angers (UA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), and ProdInra, Migration
Subjects: Small interfering RNA, NANOCARRIERS, Genetic enhancement, siRNA lipid nanocapsules, 02 engineering and technology, Applied Microbiology and Biotechnology, Polyethylene Glycols, Drug Delivery Systems, TUMOR, [SDV.IDA]Life Sciences [q-bio]/Food engineering, NANOPARTICLES, Nanotechnology, RNA, Small Interfering, Cytotoxicity, Melanoma, INTERFERENCE, 0303 health sciences, Liposome, General Medicine, Transfection, [SDV.IDA] Life Sciences [q-bio]/Food engineering, 021001 nanoscience & nanotechnology, Lipids, CANCER, Molecular Medicine, lipids (amino acids, peptides, and proteins), 0210 nano-technology, Cell Survival, [SPI.GPROC] Engineering Sciences [physics]/Chemical and Process Engineering, CH50 assay, Cryo-TEM imaging, Biology, 03 medical and health sciences, DELIVERY, Gene therapy, Nanocapsules, In vivo, Cell Line, Tumor, Humans, Gene silencing, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Gene Silencing, PERMEABILITY, 030304 developmental biology, Genetic Therapy, DNA, EFFICACY, Molecular biology, Cancer research, PEGylation, RNA
Abstract: International audience; Small interfering RNA (siRNA)-mediated gene therapy is a promising strategy to temporarily inhibit the expression of proteins implicated in carcinogenesis or chemotherapy resistance. Although intra-tumoral administration can be envisaged, studies currently focus on formulating nanomedicines for intravenous injection to target tumor sites as well as metastases. The development of synthetic nanoparticles and liposomes has advanced greatly during the last decade. The objective of this work consists in formulating and optimizing the encapsulation of siRNA into lipid nanocapsules (LNCs) for efficient gene therapy to target melanoma cells. SiRNA LNCs were prepared from DOTAP/DOPE lipoplexes, and the siRNA amount and lipid/siRNA charge ratio were assayed to improve the stability and the encapsulation yield. Cryo-TEM imaging of the siRNA lipoplexes and LNC morphology revealed specific organization of the siRNA DOTAP/DOPE lipoplexes as well as specific lipid microstructures that can be eliminated by purification. No cytotoxicity of the siRNA LNCs against the melanoma SK-Mel28 cell line was observed at concentrations of up to 500 ng/mL siRNA. In vitro siRNA transfection experiments, compared to Oligofectamine (TM), demonstrated interesting targeted gene silencing effects. Finally, complement activation assays confirmed the feasibility of the PEGylation of siRNA LNCs as part of a passive targeting strategy for future in vivo melanoma-and metastasis-targeting experiments.
Published: 2014
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30. Formulation of sub-micron emulsions containing docosahexaenoic acid esterified in triacylglycerols or phospholipids

Author: Tin-hinan Kabri, Delphine Bontemps, Michel Linder, Cédric Gaillard, Anne Meynier, Claude Genot, Loïc Foucat, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Laboratoire d'Ingénierie des Biomolécules (LIBio), Université de Lorraine (UL), French National Research Agency (ANR) [ANR-08-ALIA-002], and ANR
Subjects: food.ingredient, 030309 nutrition & dietetics, Phospholipid, Lecithin, Industrial and Manufacturing Engineering, 03 medical and health sciences, chemistry.chemical_compound, 0404 agricultural biotechnology, food, Phosphatidylcholine, [SDV.IDA]Life Sciences [q-bio]/Food engineering, n-3 delivery emulsion, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Co-surfactant, chemistry.chemical_classification, 0303 health sciences, Molecular diffusion, Chromatography, Physical stability, Chemistry, Fatty acid, food and beverages, 04 agricultural and veterinary sciences, General Chemistry, 040401 food science, DHA, Docosahexaenoic acid, Emulsion, lipids (amino acids, peptides, and proteins), Food Science, Biotechnology, Polyunsaturated fatty acid
Abstract: International audience; In food applications, long-chain PUFA can be carried by different lipid molecules, which can affect their end-use properties. The objective of this study was to formulate emulsions containing DHA located exclusively in phospholipids (PL-DHA) or in triacylglycerols (TAG-DHA) and with similar fatty acid profiles and organization. Food grade oils and lecithins were blended on the basis of their fatty acid (FA) contents and submitted to high-pressure homogenization with mineral water. The lecithin containing PL-DHA allowed to stabilize oil-in-water emulsion with droplet average diameter around 240nm thank to the interfacial molecular packing of the PL species comprising lyso and anionic phospholipids. Small particles around 40nm were also highlighted by transmission electron microscopy (TEM). To stabilize TAG-DHA emulsion with mainly soybean phosphatidylcholine, Tween-80 was selected among other co-emulsifiers. This TAG-DHA emulsion presented an average droplet diameter of 203nm and contained small particles (20nm) viewed by TEM. It had less negative droplet charge and lower supramolecular diffusion coefficient than PL-DHA emulsion. It was less physically stable than PL-DHA emulsion whose droplet size distribution remained unchanged during at least 19 days at 37 degrees C concomitantly with an increase of H-1 NMR FA molecular diffusion coefficient. Practical applications: The sub-micron emulsions designed in this study were physically stable during storage. They were prepared with food-grade oils and characterized by similar FA compositions and structures. They can be used as delivery systems with FA compositions responding to nutritional recommendations.
Published: 2013
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31. One and two dimensional self-assembly of comb-like amphiphilic copolyelectrolytes in aqueous solution

Author: Wissam Moussa, Christophe Chassenieux, C. Limouzin-Morel, I. Iliopoulos, Cédric Gaillard, Fabien Dutertre, Denis Bendejacq, Taco Nicolai, Sciences et Ingénierie de la Matière Molle (SIMM), ESPCI ParisTech-PSL Research University (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut des Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Laboratoire Matière Molle et Chimie (MMC), ESPCI ParisTech-Centre National de la Recherche Scientifique (CNRS), RHODIA RECHERCHES ET TECHNOLOGIES CENTRE DE RECHERCHES ET TECHNOLOGIES D'AUBERVILLIERS, RHODIA RECHERCHES ET TECHNOLOGIES, Sciences et Ingénierie de la Matière Molle (UMR 7615) (SIMM), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), French Research Ministry (MNRT grant), and Region Pays de la Loire
Subjects: Materials science, STYRENE, CATIONIC SURFACTANT PHASES, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, LAMELLAR PHASES, SYSTEMS, Amphiphile, Copolymer, WATER, ComputingMilieux_MISCELLANEOUS, chemistry.chemical_classification, Aqueous solution, General Chemistry, Polymer, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Grafting, Small-angle neutron scattering, COPOLYMERS, 0104 chemical sciences, Crystallography, POLYMERIZATION, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, Self-healing hydrogels, X-RAY, SHEAR, Self-assembly, 0210 nano-technology, OLIGOMERIC SURFACTANTS
Abstract: International audience; The spontaneous self-assembly of a novel comb-like amphiphilic copolyelectrolyte in water was studied by small angle neutron scattering and freeze fracture transmission electron microscopy. The copolymer was synthesized by randomly grafting pendant quaternized alkylamine moieties to a poly(styrene) chain. The effects of the grafting density and the length of the alkyls (C12-C18) on the structure were investigated systematically. The polymers were soluble over a broad range of grafting densities (35-80 mol%) where they assembled either into lamellae (35-55 mol%) consisting of a double layer of polymers or cylinders (65-80 mol%) formed by bundling of several chains. At higher concentrations, electrostatic repulsion drove smectic and hexagonal ordering of, respectively, the lamellae and the rods. TEM images showed micro-domains of stacked lamellae that were in some cases closed upon themselves to form onion-like particles. Exposure of hydrophobic patches at the surface due to defects of the self-assembly led to the formation of bonds between lamellae or cylinders. As a consequence visco-elastic solutions or hydrogels were formed at higher concentrations.
Published: 2013
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32. Design of interfacial films to control lipid oxidation in oil-in-water emulsions

Author: Marie-Hélène Ropers, Cédric Gaillard, Dominique Guibert, C. Berton-Carabin, Claude Genot, ProdInra, Migration, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Université Paris Descartes - Paris 5 (UPD5). Paris, FRA., INRA, and Region Pays de la Loire
Subjects: Aggregates, PH, IMPACT, 030309 nutrition & dietetics, General Chemical Engineering, PHYSICAL STRUCTURES, Phospholipid, HEAT, Conjugated system, Hexanal, EMULSIFIER, Oil in water, 03 medical and health sciences, chemistry.chemical_compound, 0404 agricultural biotechnology, Lipid oxidation, Phosphatidylcholine, [SDV.IDA]Life Sciences [q-bio]/Food engineering, Organic chemistry, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, 0303 health sciences, STABILITY, Chemistry, Atomic force microscopy, Emulsion, Protein, Structure, 04 agricultural and veterinary sciences, General Chemistry, Interface, [SDV.IDA] Life Sciences [q-bio]/Food engineering, 040401 food science, BETA-LACTOGLOBULIN, [SDV.AEN] Life Sciences [q-bio]/Food and Nutrition, Chemical engineering, TRANSGLUTAMINASE, [SDV.AEN]Life Sciences [q-bio]/Food and Nutrition, Food Science
Abstract: International audience; In oil-in-water (O/W) emulsions, the droplets covered by native proteins are more prone to oxidation than droplets covered by surfactants. We attempted in this work to improve the barrier properties of protein-stabilized interfacial layers by controlled modifications of their composition and structure. Native bovine beta-lactoglobulin (BLG) or beta-casein (BCN), partially aggregated BLG and mixtures of the proteins with dilauroyl phosphatidylcholine (DLPC) were used to prepare emulsions and reconstituted Langmuir-Blodgett films. Lipid oxidation in the emulsions, as evaluated from oxygen uptake and formation of conjugated dienes, propanal and hexanal was roughly unmodified with aggregated BLG and DLPC-BLG mixtures and even favored with DLPC-BCN mixtures. The reconstituted phospholipid/protein interfacial layers presented interfacial heterogeneity evidenced by atomic force microscopy (AFM). This indicates that the structural homogeneity of the interface could be a key factor in controlling lipid oxidation. (C) 2013 Elsevier Ltd. All rights reserved.
Published: 2012
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33. Rheological behaviour and microstructure of microfibrillated cellulose suspensions/low-methoxyl pectin mixed systems. Effect of calcium ions

Author: Cédric Gaillard, Catherine Garnier, Jean-Louis Doublier, Sylvie Durand, G. Agoda-Tandjawa, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), and Institut National de la Recherche Agronomique (INRA)
Subjects: polysaccharide mixture, Thixotropy, food.ingredient, LM pectin, Polymers and Plastics, Pectin, Sodium, Composite number, microstructure, chemistry.chemical_element, 02 engineering and technology, Calcium, 010402 general chemistry, 01 natural sciences, chemistry.chemical_compound, food, Rheology, cellulose / LM pectin composite, [SDV.IDA]Life Sciences [q-bio]/Food engineering, Materials Chemistry, microfibrillated cellulose suspensions, Cellulose, Composite material, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Organic Chemistry, food and beverages, 021001 nanoscience & nanotechnology, Microstructure, cations, 0104 chemical sciences, chemistry, Chemical engineering, microscopy, rheology, 0210 nano-technology
Abstract: International audience; In this study, the influence of the presence of low-methoxyl pectin (LM pectin) on the rheological and microstructural properties of microfibrillated cellulose suspensions was elucidated in order to create new structures with new and interesting textures. For that purpose, the rheological properties of the cellulose/LM pectin mixtures in variable proportions were compared with those of the individual biopolymers. The influence of the presence of calcium and/or sodium ions on the properties of the mixed systems was studied. The microstructure of the resulting system was studied by transmission electron microscopy and confocal laser scanning microscopy. It was found that, in the presence of LM pectin, a synergistic effect was observed when calcium ions were also present, leading to increased rheological properties of the composites. Indeed, addition of calcium to the mixtures induced LM pectin gelation, which was favoured in the presence of sodium, the pectin network contributing to the formation of a stronger cellulose/LM pectin composite gel. The presence of LM pectin alone in the microfibrillated cellulose suspensions does not significantly modify the viscoelastic and microstructural properties of microfibrillated cellulose suspensions. Whether calcium was added to the mixtures or not in water, the viscoelastic properties of the mixtures are mainly controlled by cellulose. The same behaviour was observed for the mixtures in NaCl without added calcium. Contrary to this observation, it was noticed that in presence of both sodium and calcium ions, the viscoelastic properties of the mixtures are largely governed by LM pectin. On the other hand, it was showed that the flow behaviour of microfibrillated cellulose suspensions is modified in the presence of LM pectin with an increase in thixotropic character shear-thinning behaviour, which was more pronounced in the presence of NaCl. It was also shown, from TEM observations, that an interpenetrating network formed in cellulose/LM pectin composites gel in the presence of calcium ions. In the same way, the CLSM observations allowed the separate localization of cellulose and LM pectin within the composite systems to be highlighted. The results obtained suggests that it is possible to thus create new structures with new interesting textures, by mixing microfibrillated cellulose suspensions and LM pectin in suitable proportions in the simultaneous presence of both sodium and calcium ions.
Published: 2012
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34. Properties of cellulose/pectins composites. Implication for structural and mechanical properties of cell wall

Author: Jean-Louis Doublier, Catherine Garnier, Cédric Gaillard, G. Agoda-Tandjawa, Sylvie Durand, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), and French Research Ministry
Subjects: Polymers and Plastics, Surface Properties, microstructure, Viscoelastic Substances, 02 engineering and technology, engineering.material, mechanical properties, Polysaccharide, Viscoelasticity, Nanocomposites, Cell wall, 03 medical and health sciences, chemistry.chemical_compound, pectins, Biopolymers, Rheology, Cell Wall, Materials Chemistry, Side chain, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, Cellulose, Composite material, 030304 developmental biology, chemistry.chemical_classification, 0303 health sciences, Viscosity, Osmolar Concentration, Organic Chemistry, food and beverages, Polymer, 021001 nanoscience & nanotechnology, cations, Elasticity, cellulose, Biomechanical Phenomena, primary plant cell wall, chemistry, engineering, microscopy, Calcium, rheology, Biopolymer, Beta vulgaris, 0210 nano-technology
Abstract: International audience; The primary cell wall of dicotyledonous plants can be considered as a concentrated polymer assembly, containing in particular polysaccharides among which cellulose and pectins are known to be the major components. In order to understand and control the textural quality of plant-derived foods, it is highly important to elucidate the rheological and microstructural properties of these components, individually and in mixture, in order to define their implication for structural and mechanical properties of primary plant cell wall. In this study, the rheological and microstructural properties of model systems composed of sugar-beet microfibrillated cellulose and HM pectins from various sources, with varied degrees of methylation and containing different amounts of neutral sugar side chains, were investigated. The influence of the presence of calcium and/or sodium ions and the biopolymer concentrations on the properties of the mixed systems were also studied. The characterizations of the mixed system, considered as a simplified model of primary plant cell wall, showed that whatever the structural characteristics of the pectins, the ionic conditions of the medium and the biopolymer concentrations, the gelation of the composite was mainly controlled by cellulose. Thus, the cellulose network would be the principal component governing the mechanical properties of the cell walls. However, the neutral sugar side chains of the pectins seem to play a part in the interactions with cellulose, as shown by the interesting viscoelastic properties of cellulose/apple HM pectins systems. The rigidity of cellulose/pectins composite was strongly influenced by the structural characteristics of pectins. The particular properties of primary plant cell walls would thus result from the solid viscoelastic properties of cellulose, its interactions with pectins according to their structural characteristics (implication of the neutral sugar side chains and the specific potential calcic interactions) and of the distribution of the components in separate phases.
Published: 2012
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35. Smart Foams: Switching Reversibly between Ultrastable and Unstable Foams

Author: Anne-Laure, Fameau, Arnaud, Saint-Jalmes, Fabrice, Cousin, Bérénice, Houinsou Houssou, Bruno, Novales, Laurence, Navailles, Janine, Emile, Frédéric, Nallet, Cédric, Gaillard, François, Boué, Jean-Paul, Douliez, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Laboratoire Léon Brillouin (LLB - UMR 12), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay, Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Centre de recherches Paul Pascal (CRPP), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Interfaces, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Micelle, Catalysis, chemistry.chemical_compound, Adsorption, Scattering, Small Angle, Fatty acids, Coalescence (physics), Microscopy, Confocal, Tubes, Air, Temperature, Water, Foams, General Medicine, General Chemistry, Limiting, Self-assembly, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Neutron Diffraction, Monomer, [CHIM.POLY]Chemical Sciences/Polymers, Chemical engineering, chemistry, lipids (amino acids, peptides, and proteins), 0210 nano-technology, [PHYS.COND.CM-SCM]Physics [physics]/Condensed Matter [cond-mat]/Soft Condensed Matter [cond-mat.soft], Stearic Acids
Abstract: 6 pages; International audience; Ultrastable foams with an optimal foamability have been obtained using hydroxyl fatty acids tubes. The stabilization results from the adsorption of monomers at the air-water interface preventing coalescence and coarsening and from the presence of tubes in the Plateau borders limiting the drainage. Upon heating, tubes transit to micelles, which induces foam destabilization. Such foams are thus the first to have a temperature tunable stability.
Published: 2011
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36. DNA-Polymer micelles as nanoparticles with recognition ability

Author: Renée Mayap Talom, Christel Cerclier, Cédric Gaillard, Fabienne Gauffre, Julian Oberdisse, Leonard Kaps, Gad Fuks, Christophe Mingotaud, Interactions moléculaires et réactivité chimique et photochimique (IMRCP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Université Fédérale Toulouse Midi-Pyrénées, Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Léon Brillouin (LLB - UMR 12), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay, Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut des Technologies Avancées en sciences du Vivant (ITAV), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), The authors thank all the present and former collaborators of the project 'DNATOOL'. We acknowledge the Agence Nationale de la Recherche for funding (program ANR PNANO-07) and the Laboratoire d'Analyse et d'Architecture des Systemes (LAAS-CNRS) for access to Nanoscope 3., Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Fluides, Energie, Réacteurs, Matériaux et Transferts (FERMAT), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Polymers, micelles, Polyesters, Oligonucleotides, Nanoparticle, surface patterning, Nanotechnology, 02 engineering and technology, macromolecular substances, 010402 general chemistry, chemistry, 01 natural sciences, Micelle, Catalysis, chemistry.chemical_compound, Molecular recognition, [SDV.IDA]Life Sciences [q-bio]/Food engineering, Copolymer, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Particle Size, chemistry.chemical_classification, Oligonucleotide, Organic Chemistry, technology, industry, and agriculture, General Chemistry, Polymer, Quartz crystal microbalance, DNA, 021001 nanoscience & nanotechnology, 0104 chemical sciences, block copolymers, Chemical engineering, Nanoparticles, molecular recognition, 0210 nano-technology, Caprolactone, oligonucleotides, multidisciplinary
Abstract: International audience; The Watson-Crick binding of DNA single strands is a powerful tool for the assembly of nanostructures. Our objective is to develop polymer nanoparticles equipped with DNA strands for surface-patterning applications, taking advantage of the DNA technology, in particular, recognition and reversibility. A hybrid DNA copolymer is synthesized through the conjugation of a ssDNA (22-mer) with a poly(ethylene oxide)-poly(caprolactone) diblock copolymer (PEO-b-PCl). It is shown that, in water, the PEO-b-PCl-ssDNA(22) polymer forms micelles with a PCl hydrophobic core and a hydrophilic corona made of PEO and DNA. The micelles are thoroughly characterized using electron microscopy (TEM and cryoTEM) and small-angle neutron scattering. The binding of these DNA micelles to a surface through DNA recognition is monitored using a quartz crystal microbalance and imaged by atomic force microscopy. The micelles can be released from the surface by a competitive displacement event.
Published: 2011
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37. Properties and Catalytic Activities of New Easily-Made Amphiphilic Phosphanes for Aqueous Organometallic Catalysis

Author: Cédric Gaillard, Michel Ferreira, David Landy, Hervé Bricout, Nathalie Azaroual, Eric Monflier, Sébastien Tilloy, Université Lille Nord de France (COMUE), Université d'Artois (UA), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, Faculté de pharmacie, Université de Lille, Droit et Santé, Chimie organique et macromoléculaire (COM), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Université du Littoral Côte d'Opale (ULCO), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Synthèse Organique et Environnement (LSOE), MREI, and Université du Littoral Côte d'Opale (ULCO)-Université du Littoral Côte d'Opale (ULCO)-Université du Littoral Côte d'Opale (ULCO)
Subjects: Supramolecular chemistry, 010402 general chemistry, PHOSPHANE LIGANDS, 01 natural sciences, Catalysis, Tsuji–Trost reaction, Polymer chemistry, Amphiphile, [SDV.IDA]Life Sciences [q-bio]/Food engineering, Organic chemistry, WATER, PHOSPHANE, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, AMPHIPHILES, Alkyl, chemistry.chemical_classification, CALORIMETRIE ISOTHERME A TITRATION, AQUEOUS-PHASE CATALYSIS, Aqueous solution, 010405 organic chemistry, Isothermal titration calorimetry, General Chemistry, TSUJI–TROST REACTION, 0104 chemical sciences, chemistry, Reagent
Abstract: International audience; Mono- and disulfonated amphiphilic versions of triphenylphosphane (PPh3) and cyclohexyl(phenyl)phosphane were easily synthesized from commercial reagents and sulfuric acid. The behaviour of these phosphanes in solution was investigated by surface tension, isothermal titration calorimetry, nuclear magnetic resonance and cryo-transmission electron microscopy. Two different supramolecular assemblies were evidenced according to the degree of sulfonation. The monosulfonated phosphanes formed well organized micelle-like aggregates while the disulfonated phosphanes formed heterogeneous and disorganized vesicle-like assemblies. The efficiency of these amphiphilic phosphanes was evaluated in the aqueous biphasic, palladium-catalyzed cleavage of allyl alkyl carbonates
Published: 2010
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38. Self-similar assemblies of globular whey proteins at the air-water interface: Effect of the structure

Author: Alain Riaublanc, François Boué, Cédric Gaillard, Najet Mahmoudi, Monique A.V. Axelos, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Laboratoire Léon Brillouin (LLB - UMR 12), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay
Subjects: Whey protein, Globular protein, Surface Properties, Static Electricity, 02 engineering and technology, Surface pressure, 01 natural sciences, Light scattering, Biomaterials, Colloid and Surface Chemistry, Adsorption, Dynamic light scattering, 0103 physical sciences, Monolayer, Scattering, Small Angle, Pressure, Surface Tension, chemistry.chemical_classification, 010304 chemical physics, Chemistry, Protein Stability, Air, Cryoelectron Microscopy, Osmolar Concentration, Water, 021001 nanoscience & nanotechnology, Milk Proteins, Small-angle neutron scattering, Elasticity, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Crystallography, Neutron Diffraction, Whey Proteins, Chemical physics, Emulsifying Agents, Protein Multimerization, 0210 nano-technology, Rheology, [CHIM.OTHE]Chemical Sciences/Other
Abstract: International audience; We investigated the structure of heat-induced assemblies of whey globular proteins using small angle neutron scattering (SANS), static and dynamic light scattering (SLS and DLS), and cryogenic transmission electron microscopy (Cryo-TEM). Whey protein molecules self-assemble in fractal aggregates with a structure density depending on the electrostatic interactions. We determined the static and dynamic properties of interfacial layer formed by the protein assemblies, upon adsorption and spreading at the air-water interface using surface film balance and interfacial dilatational rheology. Upon spreading, all whey protein systems show a power-law scaling behavior of the surface pressure versus concentration in the semi-dilute surface concentration regime, with an exponent ranging from 5.5 to 9 depending on the electrostatic interactions and the aggregation state. The dilatational modulus derived from surface pressure isotherms shows a main peak at 6-8 mN/m, generally considered to be the onset of a conformational change in the monolayer, and a second peak or a shoulder at 15 mN/m. Long-time adsorption kinetics give similar results for both the native whey proteins and the corresponding self-similar assemblies, with a systematic effect of the ionic strength
Published: 2010
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39. Self-Assembly and Foaming Properties of Fatty Acid-Lysine Aqueous Dispersions

Author: Alain Riaublanc, Cédric Gaillard, Frédéric Nallet, Bruno Novales, Jean-Paul Douliez, Laurence Navailles, Bérénice Houinsou Houssou, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Centre de recherches Paul Pascal (CRPP), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1, and Centre National de la Recherche Scientifique (CNRS)
Subjects: Magnetic Resonance Spectroscopy, Carboxylic acid, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Micelle, Microscopy, Electron, Transmission, Electrochemistry, Organic chemistry, Aerosols and foams, General Materials Science, Spectroscopy, Alkyl, Micelles, Unilamellar Liposomes, chemistry.chemical_classification, Aqueous solution, Calorimetry, Differential Scanning, Chemistry, Vesicle, Lysine, Fatty Acids, Temperature, Fatty acid, Surfaces and Interfaces, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Small-angle neutron scattering, Liquid-liquid interfaces, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Chemical engineering, Saturated fatty acid, lipids (amino acids, peptides, and proteins), Lyotropic phases, 0210 nano-technology, 61.30.St, 68.05.-n, 82.70.Rr, [PHYS.COND.CM-SCM]Physics [physics]/Condensed Matter [cond-mat]/Soft Condensed Matter [cond-mat.soft]
Abstract: 6 pages; International audience; We report on dispersions of fatty acid-lysine salts in aqueous solutions which are further used to produce foams. The alkyl chain length is varied from dodecyl to stearic. In aqueous solutions, the lysine salt of the dodecyl chain yields an isotropic solution, probably micelles, whereas for longer alkyl chains, vesicles formed but crystallized upon resting at room temperature or when kept at 4 C. Solid stateNMRshowed that in vesicles fatty acids are embedded in a lamellar arrangement passing from a gel to a fluid state upon heating; the transition temperature at which it occurs was determined by DSC. Those results are confirmed by small-angle neutron scattering which also give additional information on the bilayer structure. Incredibly stable foams are obtained using the palmitic acid/Lys salt whereas for other alkyl chain length, poor or no foam is formed. We conclude that the foamability is related to the phase behavior in aqueous solution.
Published: 2010
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40. Dynamic and supramolecular organisation of α-lactalbumin/lysozyme microspheres: A microscopic study

Author: Saïd Bouhallab, Cédric Gaillard, Thomas Croguennec, Michaël Nigen, and Marie-Noelle Madec
Subjects: Morphology (linguistics), apo α-LA, Globular protein, [SDV]Life Sciences [q-bio], Biophysics, Supramolecular chemistry, FITC, 02 engineering and technology, CSLM, Microscopy, Atomic Force, Biochemistry, Microsphere, RBITC, chemistry.chemical_compound, 0404 agricultural biotechnology, Microscopy, Electron, Transmission, assembly mechanism, [SDV.IDA]Life Sciences [q-bio]/Food engineering, LYS, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, lysozyme, Total protein, Lactalbumin, chemistry.chemical_classification, Microscopy, Confocal, Atomic force microscopy, Organic Chemistry, 04 agricultural and veterinary sciences, 021001 nanoscience & nanotechnology, 040401 food science, Crystallography, microspheres, chemistry, SEM, Microscopy, Electron, Scanning, TEM, Muramidase, Lysozyme, Protein Multimerization, AFM, 0210 nano-technology, Apoproteins, α-lactalbumin
Abstract: International audience; Apo α-lactalbumin (apo α-LA) and lysozyme (LYS), two homologous globular proteins have been shown to be able to interact and self-assemble to form microspheres. We report on the organisation and the mechanism of such protein assembly process using a variety of microscopic techniques. We demonstrated that proteins involved into apo α-LA/LYS microspheres exchange with those free in solution. The exchange process takes place from the periphery to the centre of the microspheres. The formed spherical particles observed after fixed incubation time were found to be either individual or aggregated according to the total protein concentration leading to structures with different size and morphology. It appears that protein assembly occurs throughout successive steps of aggregated spherical particles that reorganise into biggest isolated microspheres. Direct microscopic observations over time confirm that microspheres resulted from a reorganisation of aggregated, clustered nanospheres. We propose that the formation of apo α-LA/LYS microspheres follows an "aggregation-reorganisation" mechanism.
Published: 2009
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41. Self-Assembling Properties of Well-Defined Poly(ethylene oxide)- b -poly(ethyl acrylate) Diblock Copolymers

Author: Cédric Gaillard, Sandie Piogé, Sagrario Pascual, Erwan Nicol, Laurent Fontaine, Institut des Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), and Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: POLYMERISATION RADICALAIRE CONTROLEE, Materials science, Polymers and Plastics, CRYO-TRANSMISSION ELECTRON MICROSCOPY, Dispersity, COPOLYMERE A BLOCS, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Micelle, AGGEGATION NUMBER, MICROSCOPIE ELECTRONIQUE A TRANSMISSION, Inorganic Chemistry, chemistry.chemical_compound, NOMBRE D'AGREGATION, Dynamic light scattering, SELF ASSEMBLY, Polymer chemistry, Materials Chemistry, Copolymer, Static light scattering, FLUORESCENCE, ComputingMilieux_MISCELLANEOUS, POLYETHYLENE OXYDE, Atom-transfer radical-polymerization, Organic Chemistry, ATOM TRANSFER RADICAL POLYMERIZATION, technology, industry, and agriculture, COPOLYMERE AMPHIPHILE, POLYETHYL ACRYLATE, DIBLOCK COPOLYMER, MICELLE, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, TRANSMISSION ELECTRON MICROSCOPY, 0104 chemical sciences, [CHIM.POLY]Chemical Sciences/Polymers, Chemical engineering, chemistry, Polymerization, STATIC LIGHT SCATTERING, Ethyl acrylate, 0210 nano-technology, DYNAMIC LIGHT SCATTERING
Abstract: International audience; Poly(ethylene oxide)-b-poly(ethyl acrylate) amphiphilic diblock copolymers were synthesized by atom transfer radical polymerization (ATRP). The controlled character of the polymerization was confirmed by kinetic studies, evolution of number-average molecular weight and polydispersity index with conversion: Various block copolymers with different PEA/PEO molar ratio were synthesized and their self-assembling properties in aqueous medium were studied by fluorescence measurements, static light scattering (SLS), and dynamic light scattering (DLS). The critical micelle concentrations (CMC) were determined by pyrene fluorescence analysis. The CMC was shown to decrease as the hydrophobic (PEA) block length increases. SLS and DLS allowed the determination of the aggregation numbers (N-agg) and hydrodynamic radii (R-h) of the core-shell micelles formed in water. Both N-agg and R-h exhibit a monotonic increase as a function of the PEA block length. TEM and cryo-TEM micrographs of the ! micelles showed spherical objects with a low polydispersity of sizes. The micelles formed in water are in a thermodynamic equilibrium and the aggregation number of the micelles was shown to vary with the temperature.
Published: 2009
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42. Synthesising gold nanoparticles within bola fatty acid nanosomes

Author: Cédric Gaillard, Bruno Novales, Jean-Paul Douliez, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), and Institut National de la Recherche Agronomique (INRA)
Subjects: Carboxylic acid, Palmitic Acid, Metal Nanoparticles, Nanoparticle, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, MICROSCOPIE ELECTRONIQUE A TRANSMISSION, Biomaterials, Palmitic acid, chemistry.chemical_compound, Colloid and Surface Chemistry, Microscopy, Electron, Transmission, SELF ASSEMBLY, Organic chemistry, Dichloromethane, chemistry.chemical_classification, AGENT DE SURFACAGE, NANOSOMES, Fatty acid, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, chemistry, Colloidal gold, Saturated fatty acid, Emulsion, GOLD NANOPARTICLES, FATTY ACID, Spectrophotometry, Ultraviolet, Gold, 0210 nano-technology, [CHIM.OTHE]Chemical Sciences/Other, Nuclear chemistry
Abstract: International audience; We report on the synthesis of gold nanoparticles (AuNP) stabilized by a layer of mercapto and/or hydroxyl bola palmitic acid-tetrabutyl ammonium salts (TBAOH) which form nanosomes in water. Mixing both bola fatty acids in water in various proportions allowed to tune the nanoparticle diameter from 1 to 10 nm using NaBH4 as a reductor. Those nanoparticles could be phase transferred to dichloromethane by adding a more hydrophobic counter-ion than TBAOH, its derivative with octyl chains (TOAOH). Finally, we used those AuNP to formulate emulsions, the stability of which was followed as a function of particle size and time. The emulsions were stable but creamed after several hours. We conclude that bola fatty acid nanosomes are then good candidates to synthesize gold nanoparticles dispersed either in water, organic solvents and emulsions.
Published: 2009
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43. Relation between Chemical Structure and Supramolecular Organization of Synthetic Lignin-Pectin Particles

Author: Bernard Cathala, Marie-Christine Ralet, Cédric Gaillard, Anouck Habrant, Dider Lairez, Fractionnement des AgroRessources et Environnement (FARE), Université de Reims Champagne-Ardenne (URCA)-Institut National de la Recherche Agronomique (INRA), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: 0106 biological sciences, Citrus, food.ingredient, Polymers and Plastics, Pectin, Chemical structure, [SDV]Life Sciences [q-bio], Supramolecular chemistry, DHP, Nanoparticle, Bioengineering, 02 engineering and technology, PLANT CELL WALL, 01 natural sciences, Lignin, Biomaterials, chemistry.chemical_compound, LIGNIN-DHP COMPLEX, food, PECTIN, LIGNIFICATION, [SDV.IDA]Life Sciences [q-bio]/Food engineering, Materials Chemistry, Organic chemistry, Molecule, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Phenols, Particle Size, STRUCTURE SUPRAMOLECULAIRE, ComputingMilieux_MISCELLANEOUS, Molecular Structure, COMPLEXE LIGNINE POLYOSIDE, 021001 nanoscience & nanotechnology, ELECTRON MICROSCOPY, chemistry, [SDE]Environmental Sciences, Pectins, SUPRAMOLECULAR ORGANIZATION, Particle size, LIGHT SCATTERING, 0210 nano-technology, 010606 plant biology & botany
Abstract: International audience
Published: 2009
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44. A Simple Protocol to Stabilize Gold Nanoparticles using Amphiphilic Block Copolymers: Stability Studies and Viable Cellular Uptake

Author: Cédric Ayela, Cédric Gaillard, Kamil Rahme, Fabienne Gauffre, Bruno Payré, Christophe Mingotaud, Patricia Vicendo, Interactions moléculaires et réactivité chimique et photochimique (IMRCP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Laboratoire de l'intégration, du matériau au système (IMS), Université Sciences et Technologies - Bordeaux 1-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Centre de Microscopie Électronique Appliquée à la Biologie (CMEAB), Hôpital de Rangueil, CHU Toulouse [Toulouse]-CHU Toulouse [Toulouse]-Toulouse Réseau Imagerie-Genotoul ( TRI-Genotoul), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Fluides, Energie, Réacteurs, Matériaux et Transferts (FERMAT), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS), Toulouse Réseau Imagerie-Genotoul ( TRI-Genotoul), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse 1 Capitole (UT1)-Université Toulouse - Jean Jaurès (UT2J), CHU Toulouse [Toulouse]-CHU Toulouse [Toulouse]-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées
Subjects: Nanoparticle, Metal Nanoparticles, Nanotechnology, 02 engineering and technology, CHO Cells, 010402 general chemistry, 01 natural sciences, Micelle, Catalysis, STABILITE, MICROSCOPIE ELECTRONIQUE A TRANSMISSION, Cricetulus, Microscopy, Electron, Transmission, Cricetinae, Amphiphile, Copolymer, NANOPARTICLES, Animals, CYTOTOXICITY, GOLD, AMPHIPHILES, ComputingMilieux_MISCELLANEOUS, Micelles, COPOLYMERE EN BLOC, chemistry.chemical_classification, Organic Chemistry, NANOTECHNOLOGY, General Chemistry, Polymer, Quartz crystal microbalance, 021001 nanoscience & nanotechnology, 0104 chemical sciences, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, Chemical engineering, Ionic strength, Colloidal gold, POLYMERE AMPHIPHILE, POLYMERS, 0210 nano-technology
Abstract: International audience; Di- and triblock non-ionic copolymers based on poly(ethylene oxide) and poly(propylene oxide) were studied for the stabilization of nanoparticles in water at high ionic strength. The effect of the molecular architecture (di- vs. triblock) of these amphiphilic copolymers was investigated by using gold nanoparticles (AuNPs) as probes for colloidal stability. The results demonstrate that both di- and triblock copolymers can provide long term stability, and that in both cases AuNPs are individually embedded within globules of polymers. However, in the case of diblock copolymers, the colloidal stability was related to the formation of micelles, in contrast with the case of triblock copolymers, which were previously shown to provide good stability even at concentrations at which micelles do not form. Quartz crystal microbalance (QCM) experiments showed that the presence of the hydrophobic block in the structure of the polymer is important to ensure quantitative adsorption upon a g! old surface and to limit desorption. We demonstrate that with an appropriate choice of polymer, the polymer/AuNP hybrids can also undergo filtration and freeze-drying without noticeable aggregation, which can be very convenient for further applications. Finally, preliminary studies of the cytotoxicity effect on fibroblast cells show that the polymer/AuNP hybrids were not cytotoxic. TEM micrographs on ultrathin sections of cells after incubation with the colloidal solutions show that the nanoparticles were internalized into the cells, conserving their initial size and shape.
Published: 2009
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45. Ultrastructure of Ulvan: A Polysaccharide from Green Seaweeds

Author: Jean-François Sassi, Cédric Gaillard, Audrey Robic, Yannick Lerat, Marc Lahaye, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), and Centre d'Etude et de Valorisation des Algues (CEVA)
Subjects: Morphology (linguistics), Macromolecular Substances, BIOPOLYMERS, Intrinsic viscosity, Sodium, Chemical structure, Biophysics, chemistry.chemical_element, 02 engineering and technology, Polysaccharide, Biochemistry, MICROSCOPIE ELECTRONIQUE A TRANSMISSION, Biomaterials, Boric acid, 03 medical and health sciences, chemistry.chemical_compound, Ulva, Microscopy, Electron, Transmission, Polysaccharides, [SDV.IDA]Life Sciences [q-bio]/Food engineering, Organic chemistry, Ammonium, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, 030304 developmental biology, chemistry.chemical_classification, 0303 health sciences, Aqueous solution, Molecular Structure, Chemistry, Organic Chemistry, ATOMIC FORCE MICROSCOPY, General Medicine, Hydrogen-Ion Concentration, 021001 nanoscience & nanotechnology, ELECTRON MICROSCOPY, SOLUTIONS PROPERTIES, POLYSACCHARIDE, Chemical engineering, NANOHETEROGENEITY, 0210 nano-technology, Gels
Abstract: Ultrastructural analysis of the gel forming green seaweed sulfated polysaccharide ulvan revealed a spherical-based morphology (10-18 nm diameter) more or less aggregated in aqueous solution. At pH 13 in TBAOH (tetrabutyl ammonium hydroxyde) or NaOH, ulvan formed an open gel-like structure or a continuous film by fusion or coalescence of bead-like structures, while in acidic pH conditions, ulvan appeared as dispersed beads. Low concentrations of sodium chloride, copper or boric acid induced the formation of aggregates. These results highlight the hydrophobic and aggregative behavior of ulvan that are discussed in regard to the peculiar gel formation and the low intrinsic viscosity of the polysaccharide in aqueous solution. (c) 2009 Wiley Periodicals, Inc. Biopolymers 91: 652-664, 2009.This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com.
Published: 2009
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46. Simultaneous ROMP and ATRP in Aqueous Dispersed Media: a Straightforward Strategy to Prepare Polymer Composite Particles with Original Morphologies

Author: Cédric Airaud, Emmanuel Ibarboure, Valérie Héroguez, Cédric Gaillard, Laboratoire de Chimie des Polymères Organiques (LCPO), Université de Bordeaux (UB)-Ecole Nationale Supérieure de Chimie, de Biologie et de Physique (ENSCBP)-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS), TEAM 1 LCPO, Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS), INRA-Unité BIA Plateforme BIBS-Microscopie, Institut National de la Recherche Agronomique (INRA), Centre National de la Recherche Scientifique (CNRS)-Institut Polytechnique de Bordeaux-Ecole Nationale Supérieure de Chimie, de Biologie et de Physique (ENSCBP)-Université de Bordeaux (UB)-Institut de Chimie du CNRS (INC), Team 1 LCPO : Polymerization Catalyses & Engineering, and Centre National de la Recherche Scientifique (CNRS)-Institut Polytechnique de Bordeaux-Ecole Nationale Supérieure de Chimie, de Biologie et de Physique (ENSCBP)-Université de Bordeaux (UB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Polytechnique de Bordeaux-Ecole Nationale Supérieure de Chimie, de Biologie et de Physique (ENSCBP)-Université de Bordeaux (UB)-Institut de Chimie du CNRS (INC)
Subjects: Materials science, Polymers and Plastics, Radical polymerization, 02 engineering and technology, atom-transfer radical polymerization (ATRP), 010402 general chemistry, 01 natural sciences, Living free-radical polymerization, Chain-growth polymerization, microemulsion polymerization, polymer composite particles, Polymer chemistry, Materials Chemistry, Reversible addition−fragmentation chain-transfer polymerization, Organic Chemistry, Chain transfer, 021001 nanoscience & nanotechnology, Condensed Matter Physics, ring-opening metathesis polymerization (ROMP), 0104 chemical sciences, End-group, [CHIM.POLY]Chemical Sciences/Polymers, Chemical engineering, Polymerization, miniemulsion polymerization, Precipitation polymerization, 0210 nano-technology
Abstract: International audience; The simultaneous combination of the ring-opening metathesis polymerization of norbornene and the atom-transfer radical polymerization of methyl methacrylate is used as a convenient tool to prepare polymer composite particles in a single step and using only one catalyst. The current article reviews the use of miniemulsion and microemulsion conditions to reach this aim. The two developed approaches are assessed on chemical and colloidal levels and the prepared composite particles are scrutinized from a morphological point of view.
Published: 2009

47. Multiblock copolymer behaviour of alpha-CD/PEO-based polyrotaxanes: towards nano-cylinder self-organization of alpha-CDs

Author: Alain Lapp, Dimitri A. Ivanov, Cédric Gaillard, Cyril Brochon, Pascal Hébraud, Denis V. Anokhin, Georges Hadziioannou, Christophe Travelet, Guy Schlatter, Laboratoire d'Ingenierie des Polymères pour les Hautes Technologies, Centre National de la Recherche Scientifique (CNRS)-Université Louis Pasteur - Strasbourg I, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physico-Chimie des Polymères et des Milieux Dispersés (PPMD), Université Pierre et Marie Curie - Paris 6 (UPMC)-ESPCI ParisTech-Centre National de la Recherche Scientifique (CNRS), Laboratoire Léon Brillouin (LLB - UMR 12), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay, Unité de recherche biopolymeres interactions assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, INCLUSION COMPLEXES, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, chemistry.chemical_compound, Polymer chemistry, Nano, Cylinder, SCATTERING, chemistry.chemical_classification, Cyclodextrin, Ethylene oxide, Hydrogen bond, Dimethyl sulfoxide, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, CYCLODEXTRIN, 0104 chemical sciences, Solvent, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, Chemical engineering, Crystallite, 0210 nano-technology
Abstract: International audience; The present work demonstrates that alpha-cyclodextrin/poly(ethylene oxide) (alpha-CD/PEO)-based polyrotaxanes (PRs) behave as multiblock copolymers. One block type consists of a rod-like tube made of 6 to 7 weakly stacked alpha-CDs threaded along the PEO chain. The other one is made of a naked PEO segment, i.e. the PR part that is not covered by alpha-CDs. This multiblock behaviour induces the self-organization of PRs in concentrated solution in dimethyl sulfoxide ( DMSO) at room temperature leading to the formation of nano-cylinders. These nano-cylinders consist of assemblies of roughly 60 alpha-CD rod-like tubes through hydrogen bonding. Moreover, crystallites of naked PEO segments are formed since PEO is in poor solvent conditions ( DMSO) at room temperature. Furthermore, the formation of alpha-CD nano-cylinders as well as of naked PEO segment crystallites leads to physical gelation of PRs in DMSO.
Published: 2008
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48. Convenient synthesis and properties of polypropyleneimine dendrimer-functionalized polymer nanoparticles

Author: Paresh Sanghvi, Caroline Cannizzo, Anne Delgado, Chantal Larpent, Fabrice Gouanvé, Cédric Gaillard, Gérard Bacquet, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), and Rhodia S.A.
Subjects: Materials science, Nanoparticle, 02 engineering and technology, DENDRIMERE, 010402 general chemistry, Microscopy, Atomic Force, Polypropylenes, 01 natural sciences, Nanomaterials, MICROSCOPIE ELECTRONIQUE A TRANSMISSION, Biomaterials, chemistry.chemical_compound, Microscopy, Electron, Transmission, Dendrimer, [SDV.IDA]Life Sciences [q-bio]/Food engineering, NANOPARTICLES, Organic chemistry, General Materials Science, DENDRIMERS, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, NANO-BUILDING BLOCKS, SYNTHESE, chemistry.chemical_classification, Spectroscopy, Near-Infrared, Cationic polymerization, DIFFUSION QUASIELASTIQUE DE LA LUMIERE, General Chemistry, Polymer, 021001 nanoscience & nanotechnology, 0104 chemical sciences, SYNTHETIC METHODS, Azobenzene, chemistry, Polymerization, Chemical engineering, Spectrophotometry, Ultraviolet, Polystyrene, POLYMERS, 0210 nano-technology, Biotechnology
Abstract: International audience; A simple synthesis of polymer core-dendrimer shell nanoparticles (NPs) in the 15-20-nm-diameter range is presented. Amine-terminated polypropyleneimine (PPI) dendrimers DAB-dendri-(NH2)(4) and DAB-dendri-(NH2)(16) (DAB4 and DAB16) are covalently attached to the surface of primary polystyrene-based NPs bearing reactive chlorobenzyl groups produced by microemulsion polymerization in the presence of a cationic surfactant. The grafting readily proceeds under mild conditions and leads to translucent aqueous suspensions of core-shell-type NPs with a high density of peripheral amine groups that have been characterized relative to their size and chemical composition. The dendritic shell acts as a protective ionizable outer layer and provides an improvement of the colloidal stability in neutral and acidic media. The metal-binding capacity of the PPI dendrimers is retained, and spectrophotometric titrations show that the dendrimer-grafted NPs can trap a large number of Cu2+ ions (more than 900 Cu per NP-DAB16). These properties make them potentially valuable templates for the elaboration of hybrid nanomaterials. The reactivity of the external amine groups is used to link covalently azobenzene chromophores (disperse Red 1 residues) through aza-Michael addition in aqueous suspension. This simple method gives access to colored NPs with high dye contents in the outer layer (up to 1000-1500 dye molecules per NP), which indicates that dendrimer-functionalized NPs are valuable building blocks for the construction of multifunctional nanomaterials.
Published: 2008
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49. Broad polymorphism of fatty acids with amino organosilane counterions, towards novel templates

Author: François Jérôme, Jean-Paul Douliez, Cédric Gaillard, Bruno Novales, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Laboratoire de catalyse en chimie organique (LACCO), and Université de Poitiers-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: SCANNING ELECTRON MICROSCOPY, EELS, General Chemical Engineering, SOLUTION, Myristic acid, 010402 general chemistry, 01 natural sciences, MICROSCOPIE ELECTRONIQUE A TRANSMISSION, 03 medical and health sciences, chemistry.chemical_compound, COUNTERION, DISPERSION, AMINO-ORGANOSILANE, SELF ASSEMBLY, [SDV.IDA]Life Sciences [q-bio]/Food engineering, Materials Chemistry, Organic chemistry, ELECTRON ENERGY LOSS SPECTROSCOPY, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, ComputingMilieux_MISCELLANEOUS, 030304 developmental biology, chemistry.chemical_classification, 0303 health sciences, Vesicle, General Chemistry, MICELLE, RMN DU SOLIDE, Silane, POLYMORPHISM, TRANSMISSION ELECTRON MICROSCOPY, 0104 chemical sciences, Template, VESICLE, chemistry, Polymorphism (materials science), SEM, FATTY ACID, TEM, ION ANTAGONISTE, Counterion, SOLID STATE NMR
Abstract: Amino silane salts of myristic acid are shown to exhibit a broad polymorphism forming very stable vesicles, a gel of elongated fibers, and well-dispersed submicrometric flat truncated lozenges.
Published: 2008
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50. Assessment of in vitro binding of isolated pectic domains to cellulose by adsorption isotherms, electron microscopy, and X-ray diffraction methods

Author: Catherine Garnier, Jean-François Thibault, Agata Zykwinska, Bruno Pontoire, Cédric Gaillard, Alain Buléon, Marie-Christine Ralet, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), and Institut National de la Recherche Agronomique (INRA)
Subjects: 0106 biological sciences, Morphology (linguistics), POLYSACCHARIDES PARIETAUX, Polymers and Plastics, Bioengineering, 02 engineering and technology, IN VITRO BINDING, 01 natural sciences, law.invention, Biomaterials, Cell wall, Diffusion, chemistry.chemical_compound, Adsorption, Microscopy, Electron, Transmission, X-Ray Diffraction, law, Cell Wall, Polysaccharides, Polymer chemistry, [SDV.IDA]Life Sciences [q-bio]/Food engineering, Materials Chemistry, Side chain, Scattering, Radiation, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Cellulose, Glucans, X-Rays, Hydrogen Bonding, 021001 nanoscience & nanotechnology, Xyloglucan, Microscopy, Electron, chemistry, DIFFRACTION DES RAYONS X, CELLULOSE, Pectins, Microfibril, Electron microscope, 0210 nano-technology, PECTIC DOMAIN, 010606 plant biology & botany, Hydrogen
Abstract: International audience; Isolated pectic domains representative of the pectic backbone and the neutral sugar side chains were tested for their ability to interact with cellulose in comparison to the well-known binding of xyloglucan. Pectic side chains displayed a significant in vitro binding capacity to cellulose, whereas pectic backbone domains exhibited only slight adsorption to cellulose microfibrils. To support the binding results, electron microscopy and X-ray diffraction were applied. Celluloses from bacteria and sugar beet cell walls were used as substrates for the precipitation of isolated pectic domains or xyloglucan by acetone vapor diffusion. Pectic side chains grew attached to the cellulose surfaces, whereas pectic backbone domains were observed separately from cellulose microfibrils. Xyloglucan seeded with cellulose provoked a decrease of microfibrils entanglement, but no clear cross-links between neighboring microfibrils were observed. These results led to the elucidation of the pectic! domains responsible for binding with cellulose microfibrils.
Published: 2007
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