One-step Hybrid Preparation of Glucose Oxidase-Gold Nanoparticle and Electron Transfer Mechanism in the Hybrid Electrode System

Abstract

A nanometer-sized gold nanoparticle (AuNP)–glucose oxidase (GOx) hybrid has been prepared by a single-step procedure. This paper examines the roles of AuNPs in the enzyme activity of the hybrids by considering electrochemical and fluorescence measurements. The immobilization of the hybrids on a glassy carbon electrode led to an increase in a current response of 2.5 times, compared to that of GOx. On the other hand, there was no difference in the fluorescence intensity based on the production of hydrogen peroxide through the enzyme reaction in between GOx and AuNP–GOx. These results indicate that AuNPs in the hybrid does not affect the enzyme activity, but promotes an electron transfer originated through an enzyme reaction to the electrode.