Département de chimie moléculaire

The carbon cavity microelectrode (CME), exhibiting a vol. of 4 × 10-6 cm3, offers a genuine alternative for immobilizing and connecting enzymes in aq. electrolytes by powder of insol. redox materials. In the present work, the electrochem. behavior of two redox species such as ferrocene (Fc) and tetrathiafulvalene (TTF) was investigated with CME to evaluate their potentialities in the elec. wiring of enzymes. For this purpose, powder of two enzymes, glucose oxidase (GOx) and horseradish peroxidase (HRP), was independently mixed with an insol. redox material and forced to fill the single micro cavity of a carbon electrode covered by an inert insulator. The presence of the electroactive species, as well as the enzyme wiring was investigated by cyclic voltammetry. The amperometric detection of glucose was carried out by potentiostating the TTF/GOx and the Fc/GOx microelectrodes at 0.25 and 0.35 V resp. The amperometric detection of H2O2 by the TTF/HRP microelectrode was performed at -0.1 V vs. SCE. [on SciFinder(R)]