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211.
Bertrand Reuillard Solène Gentil Marie Carrière Alan Le Goff Serge Cosnier 《Chemical science》2015,6(9):5139-5143
We report the non-covalent functionalization of a multi-walled carbon nanotube (MWCNT) electrode with a biomimetic model of the horseradish peroxidase (HRP) active site. By modifying the MWCNT electrode surface with imidazole-modified polypyrrole, a new biomimetic complex of HRP was synthesized on the MWCNT sidewalls via the coordination of imidazole (Im) to the metal centre of iron protoporphyrin IX, affording (Im)(PP)FeIII. Compared to the pi-stacking of non-coordinated (PP)FeIII on a MWCNT electrode, the (Im)(PP)FeIII-modified MWCNT electrode exhibits higher electrocatalytic activity with an I max = 0.52 mA cm–2 for the reduction of H2O2, accompanied by a high onset potential of 0.43 V vs. Ag/AgCl. The performances of these novel surface-confined HRP mimics were compared to those of a MWCNT electrode modified by HRP. Although the enzyme electrode displays a higher electrocatalytic activity towards H2O2 reduction, the (Im)(PP)FeIII-modified MWCNT electrode exhibits a markedly higher operational stability, retaining 63% of its initial activity after one month. 相似文献
212.
213.
Dr. Jérémie Topin Claire A. de March Dr. Landry Charlier Prof. Dr. Catherine Ronin Prof. Dr. Serge Antonczak Dr. Jérôme Golebiowski 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(33):10227-10230
A joint approach combining free‐energy calculations and calcium‐imaging assays on the broadly tuned human 1G1 olfactory receptor is reported. The free energy of binding of ten odorants was computed by means of molecular‐dynamics simulations. This state function allows separating the experimentally determined eight agonists from the two non‐agonists. This study constitutes a proof‐of‐principle for the computational deorphanization of olfactory receptors. 相似文献
214.
Biofunctionalization of Multiwalled Carbon Nanotubes by Electropolymerized Poly(pyrrole‐concanavalin A) Films 下载免费PDF全文
Dr. Vladislav Papper Dr. Kamal Elouarzaki Dr. Karine Gorgy Ayrine Sukharaharja Dr. Serge Cosnier Prof. Robert S. Marks 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(42):13561-13564
The synthesis and electropolymerization of a pyrrolic concanavalin A derivative (pyrrole‐Con A) onto a multiwalled carbon nanotube (MWCNT) deposit is reported. Glucose oxidase was then immobilized onto the MWCNT‐poly(pyrrole‐Con A) coating by affinity carbohydrate interactions with the polymerized Con A protein. The resulting enzyme electrode was applied to the amperometric detection of glucose exhibiting a high sensitivity of 36 mA cm?2 mol?1 L and a maximum current density of 350 μA cm?2. 相似文献
215.
5‐O‐Caffeoylshikimic acid from Solanum somalense leaves: Advantage of centrifugal partition chromatography over conventional column chromatography 下载免费PDF全文
Saïda Chideh Serge Pilard Jacques Attoumbré Robert Saguez Alshaimaa Hassan‐Abdallah Dominique Cailleu Anne Wadouachi Sylvie Baltora‐Rosset 《Journal of separation science》2014,37(17):2331-2339
Solanum somalense leaves, used in Djibouti for their medicinal properties, were extracted by MeOH. Because of the high polyphenol and flavonoid contents of the extract, respectively, determined at 80.80 ± 2.13 mg gallic acid equivalent/g dry weight and 24.4 ± 1.01 mg quercetin equivalent/g dry weight, the isolation and purification of the main polyphenols were carried out by silica gel column chromatography and centrifugal partition chromatography. Column chromatography led to 11 enriched fractions requiring further purification, while centrifugal partition chromatography allowed the easy recovery of the main compound of the extract. In a solvent system composed of CHCl3/MeOH/H2O (9.5:10:5), 21.8 mg of this compound at 97% purity was obtained leading to a yield of 2.63%. Its structure was established as 5‐O‐caffeoylshikimic acid by mass spectrometry and NMR spectroscopy. This work shows that S. somalense leaves contain very high level of 5‐O‐caffeoylshikimic acid (0.74% dry weight), making it a potential source of production of this secondary metabolite that is not commonly found in nature but could be partly responsible of the medicinal properties of S. somalense leaves. 相似文献
216.
Lyskawa J Sallé M Balandier JY Le Derf F Levillain E Allain M Viel P Palacin S 《Chemical communications (Cambridge, England)》2006,(21):2233-2235
The formation of the two dimeric species [(TTF)2]+* and (TTF+*)2 can be monitored by complexation of Na+ on a calix[4]arene-TTF assembly. 相似文献
217.
Monte Carlo simulations have been used to study two different models for a weak linear polyelectrolyte in the presence of nanoparticles: (i) a rodlike and (ii) a flexible polyelectrolytes. The use of simulated annealing has made it possible to simulate a polyelectrolyte chain in the presence of several nanoparticles by improving conformation sampling and avoiding multiple minima problems when dense conformations are produced. Nanoparticle distributions along the polymer backbone were analyzed versus the ionic concentration, polyelectrolyte stiffness, and nanoparticle surface charge. Titration curves were calculated and the influences of the ionic concentration, solution pH, and number of adsorbed nanoparticles on the acid/base polyelectrolyte properties have been systematically investigated. The subtle balance of attractive and repulsive interactions has been discussed, and some characteristic conformations are presented. The comparison of the two limit models provides a good representation of the stiffness influence on the complex formation. In some conditions, overcharging was obtained and presented with respect to both the polyelectrolyte and nanoparticle as the central element. Finally, the charge mobility influence along the polyelectrolyte backbone was investigated by considering annealed and quenched polyelectrolyte chains. 相似文献
218.
Christian A.G.N. Montalbetti Thomas S. Coulter Serge G. Reignier Charlotta Grånäs Jakob Felding 《Tetrahedron letters》2006,47(33):5973-5975
We have developed synthetic protocols to generate 2-alkyl, 2-aryl and 2-acetylenyl substituted 4,6-diamino-1,3,5-triazines from the corresponding 2-chloro compound. 相似文献
219.
Fabrice Freville Tristan Richard Katell Bathany Serge Moreau 《Helvetica chimica acta》2006,89(12):2958-2974
A new strategy to cyclize short synthetic oligonucleotides on DNA or RNA target strands is described. The approach is based on metal‐templated cyclization of short synthetic oligonucleotides conjugated with two chelating 2,2′ : 6′,2′′‐terpyridine (Tpy) moieties at their 3′‐ and 5′‐ends. Cyclization after metal addition (Zn2+, Fe2+) was demonstrated by means of thermal‐denaturation experiments, MALDI‐Q‐TOF‐MS, and gel electrophoresis (PAGE). 1D‐ and 2D‐NMR Experiments were performed to analyze the association of complementary strands after metal‐mediated cyclization. Our protocol allows the efficient circularization of synthetic oligonucleotides. Thereby, the hybridization on a complementary strand was more efficient with an RNA target strand and a 2′‐O‐methylated circularized oligomer. 相似文献
220.
Serge Djekou Armand Gellis Patrice Vanelle Hussein El‐Kashef 《Journal of heterocyclic chemistry》2006,43(5):1225-1229
7‐Chloromethyl‐6‐nitro‐5H‐thiazolo[3,2‐a]pyrimidin‐5‐one ( 2 ) is obtained by cyclocondensation of 2‐aminothiazole with ethyl 4‐chloroacetoacetate. This product was shown to react with various nitronate or malonate anions under microwave irradiation to give potentially bioactive 6‐nitro‐5H‐thiazolo[3,2‐a]pyrimidin‐5‐ones. Extension to other anions centered on S atom allows for the generalization this synthetic procedure. 相似文献