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6 results on '"CICECO Department of chemistry and physics"'

1. A clinical decision support tool may help to optimise vedolizumab therapy in Crohn’s disease

Author

Dulai, Parambir S., Amiot, Aurélien, Peyrin-Biroulet, Laurent, Jairaith, Vipul, Serrero, Mélanie, Filippi, Jérome, Singh, Siddharth, Pariente, Benjamin, Loftus, Edward V., Roblin, Xavier, Kane, Sunanda, Buisson, Anthony, Siegel, Corey A., Bouhnik, Yoram, Sandborn, William J., Lasch, Karen, Rosario, Maria, Feagan, Brian G., Bojic, Daniela, Trang-Poisson, Caroline, Shen, Bo, Altwegg, Romain, Sands, Bruce E., Colombel, Jean-Frederic, Carbonnel, Franck, Kochhar, Gursimran, Meserve, Joseph, Barsky, Maria, Boland, Brigid S., Gagniere, Charlotte, Bigard, Marc-André, Zallot, Camille, Grimaud, Jean-Charles, Hebuterne, Xavier, Nachury, Maria, Desreumaux, Pierre, del Tedesco, Emilie, Bommelaer, Gilles, Koliani-Pace, Jenna L., Stefanescu, Carmen, Boureille, Arnaud, Hirten, Robert, Ungaro, Ryan, Vaysse, Thibaud, Bohm, Matthew, Varma, Sashidhar, Fischer, Monika, Hudesman, David, Chang, Shannon, Bourrier, Anne, Seksik, Philippe, Beaugerie, Laurent, Cosnes, Jacques, Sokol, Harry, Landman, Cécilia, Lukin, Dana, Weiss, Aaron, Marteau, Philippe, Dray, Xavier, Nancey, Stephane, Boschetti, Gilles, Laharie, David, Poullenot, Florian, Allez, Matthieu, Gornet, Jean-Marc, Baudry, Clautilde, Savoye, Guillaume, Moreau, Jacques, Vuitton, Lucine, Koch, Stéphane, Viennot, Stéphanie, Aubourg, Alexandre, Picon, Laurence, Pelletier, Anne-Laure, Sickersen, Gaelle, Bouguen, Guillaume, Abitbol, Vered, Chaussade, Stanislas, Nahon, Stéphane, Fumery, Mathurin, Winkfield, Betsy, Brixi-Benmansour, Hedia, Gincul, Rodica, Barberis, Jean-Christophe, Bonaz, Bruno, Michiels, Christophe, Zerbib, Frank, Beauregard, Marie Bourrier, Locher, Christophe, Davin-Couve, Sophie, Poirette, Armelle, Guillem, Laurence, Stetiu-Mocanu, Monica, Philippe, Beau, Beorchia, Sylvain, Al Qaddi, Jawad, Swaminath, Arun, Observ-Ibd, Getaid, Collaboration, Victory Cohorts, Groupe d’Étude Thérapeutique des Affections Inflammatoires du Tube Digestif (GETAID), Service d'Hépato-gastro-entérologie [CHRU Nancy], Centre Hospitalier Régional Universitaire de Nancy (CHRU Nancy), Nutrition-Génétique et Exposition aux Risques Environnementaux (NGERE), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Lorraine (UL), University of Western Ontario (UWO), Centre Hospitalier Universitaire de Nice (CHU Nice), University of California [San Diego] (UC San Diego), University of California (UC), Mayo Clinic [Rochester], Centre Hospitalier Universitaire de Saint-Etienne [CHU Saint-Etienne] (CHU ST-E), Microbes, Intestin, Inflammation et Susceptibilité de l'Hôte (M2iSH), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre de Recherche en Nutrition Humaine d'Auvergne (CRNH d'Auvergne)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Dartmouth Hitchcock Medical Center, Service de Gastroentérologie [Hôpital Beaujon], Hôpital Beaujon [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), CICECO Department of chemistry and physics, Universidade de Aveiro, Robarts Research Institute [Canada], Centre hospitalier universitaire de Nantes (CHU Nantes), Institut des Maladies de l'Appareil Digestif, Université de Nantes (UN), Centre d’Investigation Clinique de Nantes (CIC Nantes), Université de Nantes (UN)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre hospitalier universitaire de Nantes (CHU Nantes), Columbia University Irving Medical Center (CUIMC), Icahn School of Medicine at Mount Sinai [New York] (MSSM), AP-HP Hôpital Bicêtre (Le Kremlin-Bicêtre), Early detection of Colon Cancer using Molecular Markers and Microbiota (EA 7375) (EC2M3), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Assistance Publique - Hôpitaux de Marseille (APHM), Université Côte d'Azur (UCA), Service des Maladies de l'Appareil Digestif et de la Nutrition [CHRU Lille], Hôpital Claude Huriez [Lille], CHU Lille-CHU Lille-Centre Hospitalier Régional Universitaire [Lille] (CHRU Lille), Service de Gastro-entérologie et Hépatologie [CHU Saint-Etienne], Service de neurologie [Le Kremlin Bicêtre], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Bicêtre, Indiana University - Purdue University Indianapolis (IUPUI), Indiana University System, CHU Saint-Antoine [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Centre de Recherche Saint-Antoine (CRSA), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU), Institut Pierre Louis d'Epidémiologie et de Santé Publique (iPLESP), Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Equipes Traitement de l'Information et Systèmes (ETIS - UMR 8051), Ecole Nationale Supérieure de l'Electronique et de ses Applications (ENSEA)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), Sorbonne Université (SU), Autophagie infection et immunité - Autophagy Infection Immunity (APY), Centre International de Recherche en Infectiologie (CIRI), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), CHU Bordeaux [Bordeaux], Hôpital Haut-Lévêque [CHU Bordeaux], Hopital Saint-Louis [AP-HP] (AP-HP), Service d'Endocrinologie, Diabétologie, Maladies Métaboliques, Hôpital Avicenne, Nutrition, inflammation et dysfonctionnement de l'axe intestin-cerveau (ADEN), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institute for Research and Innovation in Biomedicine (IRIB), Normandie Université (NU)-Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Service d'Hépato-Gastroentérologie [CHU Rouen], Hôpital Charles Nicolle [Rouen], CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), UNIROUEN - UFR Santé (UNIROUEN UFR Santé), Normandie Université (NU)-Normandie Université (NU), Centre Hospitalier Universitaire de Toulouse (CHU Toulouse), Service de Gastro-Entérologie [CHRU Besançon], Centre Hospitalier Régional Universitaire de Besançon (CHRU Besançon), Groupe innovation et ciblage cellulaire (GICC), EA 7501 [2018-...] (GICC EA 7501), Université de Tours (UT), Hépato-Gastro-Onco-Entérologie [CHRU de Tours], Centre de recherche sur l'Inflammation (CRI (UMR_S_1149 / ERL_8252 / U1149)), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Service d'hépato-gastro-entérologie [Hôpital Saint-Louis, APHP], Groupe Hospitalier Saint Louis - Lariboisière - Fernand Widal [Paris], Hôpital Cochin [AP-HP], Université Sorbonne Paris Cité (USPC), Groupe Hospitalier Intercommunal Le Raincy-Montfermeil, Périnatalité et Risques Toxiques - UMR INERIS_I 1 (PERITOX), Institut National de l'Environnement Industriel et des Risques (INERIS)-Université de Picardie Jules Verne (UPJV)-CHU Amiens-Picardie, CHU Amiens-Picardie, Observatory on Efficacy and of Vedolizumab in Patients With Inflammatory Bowel Disease Study Group, Hôpital Edouard Herriot [CHU - HCL], Hospices Civils de Lyon (HCL), Centre Hospitalier Universitaire [Grenoble] (CHU), Service d'Hépato-Gastro-Entérologie (CHU de Dijon), Centre Hospitalier Universitaire de Dijon - Hôpital François Mitterrand (CHU Dijon), Grand Hôpital de l'Est Francilien (GHEF), Centre Hospitalier Universitaire de Saint-Etienne (CHU de Saint-Etienne), Service de gastroentérologie [CHU Saint-Etienne], Service de Gastroentérologie et nutrition [CHU Saint-Antoine], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Centre International de Recherche en Infectiologie - UMR (CIRI), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Hôpital Charles Nicolle [Rouen]-CHU Rouen, and CHU Toulouse [Toulouse]

Subjects
Adult, Male, medicine.medical_specialty, [SDV]Life Sciences [q-bio], Disease, Antibodies, Monoclonal, Humanized, Antiviral Agents, Clinical decision support system, Vedolizumab, Cohort Studies, Young Adult, 03 medical and health sciences, 0302 clinical medicine, Crohn Disease, Gastrointestinal Agents, Internal medicine, medicine, Humans, Pharmacology (medical), 030212 general & internal medicine, Young adult, Optimising Vedolizumab in Crohn's Disease, Crohn's disease, Hepatology, business.industry, Patient Selection, Gastroenterology, Middle Aged, Decision Support Systems, Clinical, medicine.disease, Hepatitis C, Treatment Outcome, Calibration, Original Article, Female, 030211 gastroenterology & hepatology, Observational study, Onset of action, Drug Monitoring, business, Algorithms, medicine.drug, Cohort study
Abstract

International audience; Background A clinical decision support tool (CDST) has been validated for predicting treatment effectiveness of vedolizumab (VDZ) in Crohn's disease. Aim To assess the utility of this CDST for predicting exposure-efficacy and disease outcomes. Methods Using data from three independent datasets (GEMINI, GETAID and VICTORY), we assessed clinical remission rates and measured VDZ exposure, rapidity of onset of action, response to dose optimisation and progression to surgery by CDST-defined response groups (low, intermediate and high). Results A linear relationship existed between CDST-defined groups, measured VDZ exposure, rapidity of onset of action and efficacy in GEMINI through week 52 (P < 0.001 at all time points across three CDST-defined groups). In GETAID, CDST predicted differences in clinical remission at week 14 (AUC = 0.68) and rapidity of onset of action (P = 0.04) between probability groups. The high-probability patients did not benefit from shortening of infusion intervals, and differences in onset of action between the high-intermediate and low-probability groups within GETAID were no longer significant when including low-probability patients who received a week 10 infusion. CDST predicted a twofold increase in surgery risk over 12 months of VDZ therapy among low- to intermediate-probability vs high-probability patients (adjusted HR 2.06, 95% CI 1.33-3.21). Conclusions We further extended the clinical utility of a previously validated VDZ CDST, which accurately predicts at baseline exposure-efficacy relationships and rapidity of onset of action and could be used to help identify patients who would most benefit from interval shortening and those most likely to require surgery while on active therapy.

Published
2019

2. Assessing Cobalt Metal Nanoparticles Uptake by Cancer Cells Using Live Raman Spectroscopy

Author

Rauwel,Erwan, Al-Arag,Siham, Salehi,Hamideh, Amorim,Carlos O, Cuisinier,Frédéric, Guha,Mithu, Rosario,Maria S, Rauwel,Protima, Estonian University of Life Sciences (EMU), Laboratoire de Bioingénierie et NanoSciences (LBN), Université Montpellier 1 (UM1)-Université de Montpellier (UM), Departamento de Fisica [Aveiro], Universidade de Aveiro, University of Tartu, and CICECO Department of chemistry and physics

Subjects
inorganic chemicals, [SDV.BIO]Life Sciences [q-bio]/Biotechnology, International Journal of Nanomedicine, cobalt nanoparticles, stem cells, label-free tool, Raman spectroscopy, cancer cells, apoptosis, cellular uptake, [SDV.CAN]Life Sciences [q-bio]/Cancer
Abstract

Erwan Rauwel1 ,* Siham Al-Arag2 ,* Hamideh Salehi,2 Carlos O Amorim,3 Frédéric Cuisinier,2 Mithu Guha,4 Maria S Rosario,5 Protima Rauwel1 1Institute of Technology, Estonian University of Life Sciences, Tartu, Estonia; 2LBN, University of Montpellier, Montpellier, France; 3Dpt. Of Physics & CICECO – Aveiro Institute of Materials, University of Aveiro, Aveiro, Portugal; 4Dpt. Of General & Molecular Pathology, Faculty of Medicine, University of Tartu, Tartu, Estonia; 5CICECO – Aveiro Institute of Materials, University of Aveiro, Aveiro, Portugal*These authors contributed equally to this workCorrespondence: Erwan Rauwel Email erwan.rauwel@emu.eePurpose: Nanotechnology applied to cancer treatment is a growing area of research in nanomedicine with magnetic nanoparticle-mediated anti-cancer drug delivery systems offering least possible side effects. To that end, both structural and chemical properties of commercial cobalt metal nanoparticles were studied using label-free confocal Raman spectroscopy.Materials and Methods: Crystal structure and morphology of cobalt nanoparticles were studied by XRD and TEM. Magnetic properties were studied with SQUID and PPMS. Confocal Raman microscopy has high spatial resolution and compositional sensitivity. It, therefore, serves as a label-free tool to trace nanoparticles within cells and investigate the interaction between coating-free cobalt metal nanoparticles and cancer cells. The toxicity of cobalt nanoparticles against human cells was assessed by MTT assay.Results: Superparamagnetic Co metal nanoparticle uptake by MCF7 and HCT116 cancer cells and DPSC mesenchymal stem cells was investigated by confocal Raman microscopy. The Raman nanoparticle signature also allowed accurate detection of the nanoparticle within the cell without labelling. A rapid uptake of the cobalt nanoparticles followed by rapid apoptosis was observed. Their low cytotoxicity, assessed by means of MTT assay against human embryonic kidney (HEK) cells, makes them promising candidates for the development of targeted therapies. Moreover, under a laser irradiation of 20mW with a wavelength of 532nm, it is possible to bring about local heating leading to combustion of the cobalt metal nanoparticles within cells, whereupon opening new routes for cancer phototherapy.Conclusion: Label-free confocal Raman spectroscopy enables accurately localizing the Co metal nanoparticles in cellular environments. The interaction between the surfactant-free cobalt metal nanoparticles and cancer cells was investigated. The facile endocytosis in cancer cells shows that these nanoparticles have potential in engendering their apoptosis. This preliminary study demonstrates the feasibility and relevance of cobalt nanomaterials for applications in nanomedicine such as phototherapy, hyperthermia or stem cell delivery.Keywords: Raman spectroscopy, cobalt nanoparticles, cancer cells, stem cells, cellular uptake, apoptosis, label-free tool

Published
2020

3. Hedgehog-shaped \Mo _\textrm368 \ cluster: unique electronic/structural properties, surfactant encapsulation and related self-assembly into vesicles and films

Author

Somenath Garai, Susovan Bhowmik, Haolong Li, Pierre Gouzerh, Tianbo Liu, Fadi Haso, Achim Müller, Helena I. S. Nogueira, Lixin Wu, Hani El Moll, Alice Merca, Fakultät für Chemie [Universität Bielefeld], Universität Bielefeld, State Key Laboratory of Supramolecular Structure and Materials, Jilin University, Department of Polymer Science, The University of Akron, University of Akron, CICECO Department of chemistry and physics, Universidade de Aveiro, Edifices PolyMétalliques (E-POM), Institut Parisien de Chimie Moléculaire (IPCM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
LANGMUIR-BLODGETT-FILMS, Langmuir, SEMIAMPHIPHILIC METHOD, Analytical chemistry, AIR/WATER INTERFACE, 02 engineering and technology, 010402 general chemistry, Surface pressure, 01 natural sciences, Delocalized electron, symbols.namesake, NANOSCALE, THERMOTROPIC LIQUID-CRYSTAL, Monolayer, [CHIM]Chemical Sciences, Alkyl, ComputingMilieux_MISCELLANEOUS, chemistry.chemical_classification, Aqueous solution, CATIONIC SURFACTANT, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 0104 chemical sciences, MOLYBDENUM BLUES, chemistry, RESONANCE RAMAN-SCATTERING, Chemical physics, symbols, COMPLEXES, Self-assembly, 0210 nano-technology, Raman scattering, BUILDING-BLOCKS
Abstract

The hedgehog-shaped {Mo-368} cluster shows unique electronic (extremely high extinction coefficient) and structural features, especially regarding its size, the high number of delocalized electrons which allows to measure the surface enhanced Raman scattering (SERS) spectrum and the option for coordination chemistry inside the cavity. Its relative instability in aqueous solution can be overcome by embedment in a hydrophobic shell of dimethyldioctadecylammonium cations. The resulting hybrid self-assembles into spherical vesicles in acetone-water mixtures, according to a process directed by hydrophobic-hydrophilic interactions. It also forms rather stable Langmuir monolayers while a second layer evolves under higher surface pressure, in accordance with a rather low alkyl surface density.

Published
2015

4. Photoluminescent lamellar bilayer mono-alkyl-urethanesils

Author

Luís D. Carlos, Mariana Fernandes, Rute A. S. Ferreira, Xavier Cattoën, Verónica de Zea Bermudez, Michel Wong Chi Man, Department of Chemistry and CQ-VR, University of Trás-os-Montes e Alto Douro, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), CICECO Department of chemistry and physics, Universidade de Aveiro, FCT, and Thèse co-tutelle ENSCM-UTAD

Subjects
Morphology, Phase transition, Materials science, Photoluminescence, Quantum yield, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Alkyl/siloxane hybrid materials, Biomaterials, EU3+ IONS, Materials Chemistry, Organic chemistry, Lamellar structure, CHAINS, SILICA, Alkyl, chemistry.chemical_classification, Sol-gel, GEL, Bilayer, HYDROPHOBIC-INTERACTIONS, Structure, H STRETCHING MODES, BRIDGED SILSESQUIOXANES, General Chemistry, Polymer, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 0104 chemical sciences, Electronic, Optical and Magnetic Materials, Order/disorder phase transition, SOLID-STATE NMR, LONG, Crystallography, chemistry, Excited state, Ceramics and Composites, Self-directed assembly, FUNCTIONALIZED ORGANIC/INORGANIC HYBRIDS, 0210 nano-technology
Abstract

13 pages; International audience; A new family of lamellar bilayer hierarchically structured mono-urethane cross-linked alkyl/siloxanes designated as mono-alkyl-urethanesils and represented by the notation m-Ut(CY)-ac, with Y = 14, 16 and 22 (where Y is the number of carbon atoms of the pendant polymer chains and ac is acid catalyzed) was prepared by the sol-gel process and self-assembly routes. The compounds were obtained as solid powders and are thermally stable up to 250 C. The alkyl chains adopt essentially all-trans conformations and are interdigitated. The degree of interpenetration depends non-linearly on the chain length. The intrincate morphology of the samples mimicks cabbage leaves or the desert rose. The present system allowed us to conclude that the nature of the cross-link exerts a key role on the properties of this sort of silsesquioxanes. The hydrogen bonded array in the monoalkyl- urethanesils is considerably weaker than that formed in the analogue mono-amidosil m-A(14) incorporating alkyl chains with 15 carbon atoms. The order/disorder phase transition temperatures of the mono-alkyl-urethanesils with Y = 14 and 16 are lower than that of m-A(14), making the former samples mechanically more resistant to consecutive heating/cooling cycles. The frequency of conformationalsensitive infrared modes of m-Ut(C16)-ac exhibit hysteresis behaviour during cooling after undergoing the order/disorder phase transition, but, unlike m-A(14), the latter transition, although reversible, is apparently time-independent. The hybrids display an efficient emission at room temperature in the blue-green spectral region with a maximum emission quantum yield value of 0.11 ± 0.01 (excited at 350-380 nm), which is of the same order of magnitude of that reported for m-A(14).

Published
2013

5. Self-structuring of lamellar bridged silsesquioxanes with long side spacers

Author

Xavier Cattoën, Luís D. Carlos, Jean Nicolas Cachia, Celso Valentim Santilli, Sónia S. Nobre, Rute A. S. Ferreira, Mariana Fernandes, Carole Carcel, Michel Wong Chi Man, José M. Sousa, Qinghong Xu, Verónica de Zea Bermudez, Faculdade de Engenharia, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Department of Chemistry and CQ-VR (UTAD), University of Trás-os-Montes e Alto Douro, Department of chemistry and physics (CICECO), ciceco, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Department of Engenharias [Vila Real], Universidade de Trás-os-Montes e Alto Douro (UTAD), UTAD - Chemistry Department, Universidade de Trás-os-Montes e Alto Douro, CICECO Department of chemistry and physics, Universidade de Aveiro, Instituto de Química/UNESP, Universidade Estadual Paulista Júlio de Mesquita Filho = São Paulo State University (UNESP), and Department of Chemistry and CQ-VR

Subjects
Materials science, [CHIM.MATE]Chemical Sciences/Material chemistry, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, Variable length, side alkylene spacers, 01 natural sciences, Structuring, 0104 chemical sciences, Surfaces, Coatings and Films, Crystallography, self-directed assembly, Materials Chemistry, bridged silsesquioxanes, Lamellar structure, structuring, sense organs, Physical and Theoretical Chemistry, 0210 nano-technology
Abstract

Diurea cross-linked bridged silsesquioxanes (BSs) C(10)C(11)C(10) derived from organosilane precursors, including decylene chains as side spacers and alkylene chains with variable length as central spacers (EtO)(3)Si- (CH(2))(10)-Y(CH(2))(n)-Y-(CH(2))(10)-Si(OEt)(3) (n = 7, 9-12; Y = urea group and Et = ethyl), have been synthesized through the combination of self-directed assembly and an acid-catalyzed sol gel route involving the addition of dimethylsulfoxide (DMSO) and a large excess of water. This new family of hybrids has enabled us to conclude that the length of the side spacers plays a unique role in the structuring of alkylene-based BSs, although their morphology remains unaffected. All the samples adopt a lamellar structure. While the alkylene chains are totally disordered in the case of the C(10)C(7)C(10) sample, a variable proportion of all-trans and gauche conformers exists in the materials with longer central spacers. The highest degree of structuring occurs for n = 9. The inclusion of decylene instead of propylene chains as side spacers leads to the formation of a stronger hydrogen-bonded urea-urea array as evidenced by two dimensional correlation Fourier transform infrared spectroscopic analysis. The emission spectra and emission quantum yields of the C(10)C(n)C(10) Cm materials are similar to those reported for diurea cross-linked alkylene-based BSs incorporating propylene chains as side spacers and prepared under different experimental conditions. The emission of the C(10)C(n)C(10) hybrids is ascribed to the overlap of two distinct components that occur within the urea cross-linkages and within the siliceous nanodomains. Time-resolved photoluminescence spectroscopy has provided evidence that the average distance between the siliceous domains and the urea cross-links is similar in the C(10)C(n)C(10) BSs and in oxyethylene-based hybrid analogues incorporating propylene chains as side spacers (diureasils), an indication that the longer side chains in the former materials adopt gauche conformations. It has also allowed us to demonstrate for the first time that the emission features of the urea-related component of the emission of alkylene-based BSs depend critically on the length of the side spacers.

Published
2011

6. A study of the distribution of chitosan onto and within a paper sheet using a fluorescent chitosan derivative

Author

Sylvie Blanc, Armando J. D. Silvestre, Rute A. S. Ferreira, Luís D. Carlos, Susana C. M. Fernandes, Carlos Pascoal Neto, Carmen S. R. Freire, Jacques Desbrières, Alessandro Gandini, Laboratoire Génie des procédés papetiers (LGP2 ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM), Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), CICECO Department of chemistry and physics, and Universidade de Aveiro

Subjects
Materials science, Luminescence, Polymers and Plastics, Chitosan derivative, macromolecular substances, 02 engineering and technology, Reflectance, engineering.material, Distribution, 010402 general chemistry, 01 natural sciences, Chitosan, chemistry.chemical_compound, Coating, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Polymer chemistry, Materials Chemistry, Coated paper, Paper sheet, Organic Chemistry, technology, industry, and agriculture, Reflectance, Penetration (firestop), 021001 nanoscience & nanotechnology, Fluorescence, 0104 chemical sciences, carbohydrates (lipids), chemistry, Chemical engineering, engineering, 0210 nano-technology, Fluorescent chitosan derivative
Abstract

International audience; A fluorescent chitosan derivative was deposited layer-by-layer onto conventional paper sheets and its distribution, in terms of both spreading and penetration, was assessed by SEM observations and emission measurements. The results showed that, on the one hand the surface distribution was highly homogeneous and, on the other hand, the penetration of chitosan within the paper pores ceased after a three layer deposit, beyond which any additional coating only produced an increase in its overall thickness and film-forming aptitude. These results show that this modified chitosan can be used as probe to optimize and understand the mechanism of the deposition of chitosan onto paper and other substrates.

Published
2009

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