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Start Over Topic 010401 analytical chemistry Publisher hal ccsd
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1. A dedicated robust instrument for water vapor generation at low humidity for use with a laser water isotope analyzer in cold and dry polar regions

Author

C. Leroy-Dos Santos, M. Casado, F. Prié, O. Jossoud, E. Kerstel, M. Farradèche, S. Kassi, E. Fourré, A. Landais, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratoire Interdisciplinaire de Physique [Saint Martin d’Hères] (LIPhy ), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Agence Nationale de la Recherche, ANR Institut Polaire Français Paul Emile Victor, IPEV: 1110, 1205 Prince Albert II of Monaco Foundation: 2487, Financial support. This research has been supported by the Prince Albert II of Monaco Foundation: 2487, Acknowledgements. The development presented in this paper was largely inspired by the initial PhD work of Janek Landsberg, which we gratefully acknowledge here. The research leading to these results has received funding from the Prince Albert II of Monaco Foundation 'ANTARCTIC-SNOW' program, the ANR 'EAIIST' project and the ADELISE 'CNRS-LEFE' program. The deployment of this instrument in the field was made possible by the logistic support from the 'NIVO2' and ADELISE 'IPEV' programs. We thank the two reviewers for their useful comments which greatly improved the article., ANR-16-CE01-0011,EAIIST,Projet International d'exploration de la calotte polaire de l'Antarctique de l'Est(2016), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)

Subjects
[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Atmospheric Science, Spectrum analyzer, 010504 meteorology & atmospheric sciences, δ18O, lcsh:TA715-787, 010401 analytical chemistry, lcsh:Earthwork. Foundations, Humidity, Atmospheric sciences, Laser, 01 natural sciences, 0104 chemical sciences, law.invention, lcsh:Environmental engineering, 13. Climate action, law, Environmental science, Polar, Precipitation, lcsh:TA170-171, Spectroscopy, Water vapor, 0105 earth and related environmental sciences
Abstract

Obtaining precise continuous measurements of water vapor isotopic composition in dry places (polar or high-altitude regions) is an important challenge. The current limitation is the strong influence of humidity on the measured water isotopic composition by laser spectroscopy instruments for low humidity levels (below 3000 ppmv). This problem is addressed by determining the relationships between humidity and measured δ18O and δD of known water standards. Here, we present the development of a robust field instrument able to generate water vapor, down to 70 ppmv, at very stable humidity levels (average 1σ lower than 10 ppmv). This instrument, operated by a Raspberry interface, can be coupled to a commercial laser spectroscopy instrument. We checked the stability of the system as well as its accuracy when expressing the measured isotopic composition of water vapor on the VSMOW–SLAP (Vienna Standard Mean Ocean Water – Standard Light Antarctic Precipitation) scale. It proved to be highly stable during autonomous operation over more than 1 year at the East Antarctic Concordia and Dumont d'Urville stations.

Published
2021

2. Secretory lipase from the human pathogen Leishmania major: Heterologous expression in the yeast Pichia pastoris and biochemical characterization

Author

Madiha Bou Ali, Youssef Gargouri, Saoussen Ben Ayed, Aymen Bali, Yassine Ben Ali, Dhafer Laouini, École Nationale d'Ingénieurs de Sfax | National School of Engineers of Sfax (ENIS), Université de Sfax - University of Sfax, Laboratoire de Transmission, Contrôle et Immunobiologie des Infections - Laboratory of Transmission, Control and Immunobiology of Infection (LR11IPT02), Institut Pasteur de Tunis, Réseau International des Instituts Pasteur (RIIP)-Réseau International des Instituts Pasteur (RIIP), and The authors would like to thank Mr. Anouar Fendri, Professor of English, who kindly proofread this paper.

Subjects
0301 basic medicine, Models, Molecular, MESH: Leishmania major/genetics, MESH: Enzyme Stability, MESH: Hydrogen-Ion Concentration, Protein Conformation, Gene Expression, MESH: Amino Acid Sequence, MESH: Base Sequence, 01 natural sciences, Biochemistry, Pichia, MESH: Protein Conformation, Enzyme Stability, MESH: Pichia/genetics, Leishmania major, MESH: Lipase/antagonists & inhibitors, Cloning, Molecular, Enzyme Inhibitors, Leishmania, MESH: Lipase/metabolism, biology, Chemistry, Temperature, General Medicine, Hydrogen-Ion Concentration, MESH: Temperature, Parasite, MESH: Biocatalysis, MESH: Models, Molecular, MESH: Gene Expression, Leishmania donovani, Triacylglycerol lipase, MESH: Sequence Alignment, MESH: Leishmania major/enzymology, Pichia pastoris, 03 medical and health sciences, Humans, MESH: Cloning, Molecular, [SDV.MP.PAR]Life Sciences [q-bio]/Microbiology and Parasitology/Parasitology, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, Amino Acid Sequence, Lipase, MESH: Humans, Base Sequence, MESH: Enzyme Inhibitors/pharmacology, 010401 analytical chemistry, MESH: Lipase/chemistry, biology.organism_classification, Yeast, 0104 chemical sciences, 030104 developmental biology, MESH: Lipase/genetics, biology.protein, Biocatalysis, Heterologous expression, Sequence Alignment
Abstract

International audience; Leishmaniasis is a parasitic reticuloendotheliosis whose pathogen is a zooflagellate belonging to the genus Leishmania transmitted by the bite of an infected phlebotome. Recently, a unique secretory lipase from the human pathogen Leishmania donovani Ldlip3 has been identified and characterized. This lipase has a high identity with a putative triacylglycerol lipase of Leishmania major (Lmlip2). In the present study, Lmlip2 was expressed in the eukaryotic heterologous expression system Pichia pastoris as tagged enzyme of 308 amino acids. Maximal protein production was reached after 2 days of fermentation. Optimal Lmlip2 lipase activity was measured using the pH stat technique at pH 8 at 26 °C using vinyl esters and triacylglycerols (true lipids) as substrates. Moreover, biochemical characterization of Lmlip2 contained in culture supernatant, illustrates that L. major secreted lipase is active and stable at low temperatures especially 26°and prefer neutral pH; concerning substrate specificityLmlip2 presents a preference for short chains lipid substrates vinyl esters such as VC2, VC3 and VC4 likewise, it is capable to hydrolyze long chain triacylglycerols like olive oil. Metal ions and surfactants tested in this study decrease Lmlip2 activity. Further studies are needed to clarify the relation between the lipase activity and the virulence. Thus, it could lead to the identification of novel targets to block cutaneous Leishmaniasis in human hosts.

Published
2018

3. Paper microfluidics for nucleic acid amplification testing (NAAT) of infectious diseases

Author

Pierre Garneret, Patrick Tabeling, Beatrice Jacquelin, Fabrice Monti, Anavaj Sakuntabhai, Pierre Lafaye, Laura Magro, Aurélia Kwasiborski, Camille Escadafal, Jessica Vanhomwegen, Jean-Claude Manuguerra, Laboratoire Microfluidique, MEMS, Nanostructures (MMN), 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)-Centre National de la Recherche Scientifique (CNRS), Cellule d'Intervention Biologique d'Urgence - Laboratory for Urgent Response to Biological Threats (CIBU), Institut Pasteur [Paris], HIV, Inflammation et persistance, Génétique fonctionnelle des Maladies infectieuses - Functional Genetics of Infectious Diseases, Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), Ingénierie des Anticorps (plate-forme) - Antibody Engineering (Platform), Centre National de la Recherche Scientifique (CNRS)-Institut Pasteur [Paris], P. T., J. C. M. and P. L. initiated the collaboration. L. M., P. G., B. J. and C. E. prepared the manuscript with the assistance of P. T. L. M., F. M. and P. T. brought expertise on paper microfluidics and technological developments. J. C. M., A. S., C. E., A. K., J. V. and P. L. helped on more biological points of view: isothermal amplifications and sample preparations., Institut Pasteur [Paris] (IP), HIV, Inflammation et persistance - HIV, Inflammation and Persistence, and Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Paper, [SDV.BIO]Life Sciences [q-bio]/Biotechnology, Microfluidics, Biomedical Engineering, Loop-mediated isothermal amplification, Bioengineering, Nanotechnology, 02 engineering and technology, Biology, 01 natural sciences, Biochemistry, Communicable Diseases, law.invention, Domain (software engineering), law, [SDV.MHEP.MI]Life Sciences [q-bio]/Human health and pathology/Infectious diseases, Lab-On-A-Chip Devices, Nucleic Acid Amplification Tests, Humans, [SDV.MHEP.ME]Life Sciences [q-bio]/Human health and pathology/Emerging diseases, 010401 analytical chemistry, General Chemistry, Nucleic acid amplification technique, Equipment Design, Lab-on-a-chip, Microfluidic Analytical Techniques, 021001 nanoscience & nanotechnology, Data science, 0104 chemical sciences, 3. Good health, Molecular Diagnostic Techniques, Low and middle income countries, Nucleic acid, 0210 nano-technology, Nucleic Acid Amplification Techniques
Abstract

International audience; The diagnosis of infectious diseases is entering a new and interesting phase. Technologies based on paper microfluidics, coupled to developments in isothermal amplification of Nucleic Acids (NAs) raise opportunities for bringing the methods of molecular biology in the field, in a low setting environment. A lot of work has been performed in the domain over the last few years and the landscape of contributions is rich and diverse. Most often, the level of sample preparation differs, along with the sample nature, the amplification and detection methods, and the design of the device, among other features. In this review, we attempt to offer a structured description of the state of the art. The domain is not mature and there exist bottlenecks that hamper the realization of Nucleic Acid Amplification Tests (NAATs) complying with the constraints of the field in low and middle income countries. In this domain however, the pace of progress is impressively fast. This review is written for a broad Lab on a Chip audience.

Published
2017

4. Electrochemical sensor for the detection of estradiol based on electropolymerized molecularly imprinted polythioaniline film with signal amplification using gold nanoparticles

Author

Cecilia Cristea, Nicole Jaffrezic-Renault, Anca Florea, Francis Vocanson, Robert Săndulescu, Interfaces & biosensors - Interfaces & biocapteurs, Institut des Sciences Analytiques (ISA), Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Université Cluj-Napoca, facultatea, Laboratoire Hubert Curien [Saint Etienne] (LHC), Institut d'Optique Graduate School (IOGS)-Université Jean Monnet [Saint-Étienne] (UJM)-Centre National de la Recherche Scientifique (CNRS), and 'This paper was published under the frame of European Social Found, Human Resources Development Operational Programme 2007-2013, project no. POSDRU/159/1.5/S/136893'.

Subjects
17-BETA-ESTRADIOL, 02 engineering and technology, Electrochemistry, 01 natural sciences, lcsh:Chemistry, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Gold nanoparticles, Detection limit, Molecularly imprinted polymer, p-Aminothiophenol, Chromatography, Estradiol, Chemistry, 010401 analytical chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Electrochemical gas sensor, Linear range, lcsh:Industrial electrochemistry, lcsh:QD1-999, Colloidal gold, Linear sweep voltammetry, POLYMERS, 0210 nano-technology, Selectivity, [CHIM.OTHE]Chemical Sciences/Other, lcsh:TP250-261
Abstract

A sensitive electrochemical molecularly imprinted sensor was developed for the detection of estradiol, by electropolymerization of p-aminothiophenol functionalized gold nanoparticles in the presence of estradiol as template molecule. The extraction of the template leads to the formation of cavities that are able to recognize and bind estradiol with high affinity. The performance of the developed sensor for the detection of estradiol was investigated by linear sweep voltammetry using a hexacyanoferrate/hexacyanoferrite solution as redox probe. The molecularly imprinted sensor exhibits a broad linear range, between 3.6 fM and 3.6 nM and a limit of quantification of 1.09 fM. Compared to the non-imprinted sensor, the imprinted sensor exhibits high affinity for the binding of estradiol. Moreover, selectivity studies, performed towards binding of testosterone, a hormone with similar chemical structure, proved high sensor selectivity. Furthermore, the molecularly imprinted sensor was applied for the analysis of spiked river samples with good recoveries. Keywords: Molecularly imprinted polymer, p-Aminothiophenol, Gold nanoparticles, Estradiol

Published
2015