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Chiral poly(thiophenes) have been synthesized by electropolymerization; they exhibit high specific rotation, stability, and conductivity and can stereoselectively recognize chiral anions used as doping agents during voltammetric cycles.

International audienceWe have studied kinetics of adsorption and properties of adsorbed bovine serum albumin (BSA) and fibrinogen (Fb) on a hydrophobic octyl surface, a hydrophilic amine surface, and a mixture of octyl and amine self-assembled monolayer (SAM) and newly synthesized hybrid SAM by using quartz crystal microbalance (QCM). In addition, we have proposed a combined kinetic and mass transfer constrained protein adsorption model. The model is fitted to a change in resonance frequency, Delta F-n/n versus time data obtained from QCM to get the kinetic rate constants, mass transfer coefficient, and spreading of adsorbed proteins. Initial rate of adsorption increases with a decrease in surface energy of the substrate. The equilibrium adsorbed amount of BSA on the hybrid surface is less than that on the mixed surface and lies in between that on octyl and amine surfaces and that of Fb is the least on hybrid surface. The analysis of variation of the dissipation factor, Delta D, with Delta F-n/n indicates that BSA is more flexible than Fb and the adsorbed layer of both proteins is softest on the hybrid surface. The relaxation times of adsorbed proteins are the slowest on the octyl surface, while those on the hybrid surface are the fastest. The analysis of secondary structures of proteins using ATR-FTIR suggests secondary structures of the proteins change during adsorption. The content of alpha-helix of the proteins increases due to adsorption on the amine surface, while that decreases on all other surfaces. The total content of a-helix and beta-sheet strongly depends on the adsorbed mass of the proteins and is weakly dependent related to elasticity and viscosity of the adsorbed proteins, respectively

The synthesis of new functionalized conducting polypyrroles bearing azacrown ethers at C-3 is described; these show selective cation binding on voltammetric cycling in organic media.The functionalization of polypyrrole has been studied for many years through the covalent bonding of various active groups on the nitrogen atom of the pyrrole nucleus, owing to the easy chemical access to such a modified monomer. Thus, the N-substitution of pyrrole with organometallic complexes derived from porphyrins,l cyclam2 or polypyridine3 has led to polypyrroles with promising modified electrode behaviour .However, it has been also largely observed that poly(Nsubstituted pyrroles) possess extremely low conductivity, of the order of 10-4 S cm-1 or less, indicating an important loss of conjugation, which strongly limits the potential interest of these polymers. On the other hand, it has been clearly shown