A Biosensor for Hydrogen Peroxide Based on Hemoglobin Peroxidase Immobilized on nano-Au/Chitosan-ZrO2/gold Electrode

Abstract

A new approach to measure with hemoglobin(Hb)/nano-Au/chitosan(CS)-ZrO2/Au-modified electrode was established. Zirconium dioxide(ZrO2) was dispersed in the chitosan(CS) to form a stable CS-ZrO2 composite. This composite was first coated on the surface of gold electrode to provide an amino group interface for assembling nano-Au, followed by the adsorption of Hb to form a bilayer of Hb/nano-Au. The Hb/nano-Au/CS-ZrO2/gold electrode was used as hydrogen peroxide (H2O2) sensor. Cycling voltammetric and chronoamperometric characterizations reveal that the modified electrode exhibit electrocatalytic behavior to H2O2. The results confirmed that the electrode exhibited high sensitivity, fast response, and linear response in the range of 3.9×10-6~1.8×10-3 mol/L(R=0.9956) with the lowest detection limit of 5.6×10-7 mol/L(S/N=3).