Electrocatalytic oxidation of glucose at a glucose oxidase-immobilized benzoquinone-mixed carbon paste electrode.

Abstract

Glucose oxidase (GOD) was immobilized on the surface of a benzoquinone (BQ)-mixed carbon paste electrode (CPE) by coating the enzyme-loaded electrode surface with a nitrocellulose film. This film-coated glucose oxidase-immobilized benzoquinone-mixed carbon paste electrode (GOD-BQ-CPE) served as a biocatalyst electrode for electro-oxidation of D-glucose. The catalytic oxidation current at 0.5V vs. SCE was analyzed as a function of the concentration of D-glucose, the amount of the mixed benzoquinone in carbon paste electrode, the amount of the immobilized enzyme on the carbon paste electrode surface and the thickness of the coating film. The kinetics of the electrocatalysis at the film-coated GOD-BQ-CPE were interpreted by the concept of the enzyme reaction layer on the carbon paste electrode surface.