Glucose Biosensor Based on Immobilization of Glucose Oxidase on Silica Nanoparticles Modified Au Electrode

Abstract

A feasible method to fabricate glucose biosensor was developed by covalent attachment of glucose oxidase (GOx) to a silica nanoparticle monolayer modified gold electrode. Electrochemical impedance spectroscopy (EIS) of ferrocyanide followed the assembly process and verified the successful immobilization of GOx on silica nanoparticle modified on gold electrodes. Cyclic voltammetry (CV), performed in the presence of excess glucose and artificial redox mediator (ferrocenemethanol), allowed to quantify the surface concentration of electrically wired enzyme. The signal of proposed electrode was more than 2.5 times of that on electrode lacking silica nanoparticles. As a result, silica nanoparticles are a good biocompatible solid support for enzyme immobilization.