Département de chimie moléculaire

A photoelectrode was designed by electrodeposition of a pyrrole monomer modified with a polypyridyl Ru(II) complex bearing benzo[i]dipyrido-[3,2-a:2'.3'-c]phenazine (dppn) ligand. Owing to the intercalating properties of these immobilized complexes towards DNA double helix, cocaine aptamer was immobilized on the modified electrodes thanks to its stem-loop configuration to design a photoelectrochem. cocaine aptasensor. Esp. using a double-fragment aptamer strategy, the binding of cocaine and the formation of the aptamer/cocaine complex was successfully obsd. and modeled by a Langmuir-Freundlich isotherm, giving access to an apparent dissocn. const. Kd of 3.8 mmol L-1. The photoelectrochem. aptasensor exhibits a LOD of 10 nmol L-1 and linear range of 1 10-8-5 10-4 mol L-1. [on SciFinder(R)]