Hydrogen peroxide sensor based on hemoglobin immobilized on glassy carbon electrode with SiO2 nanoparticles/chitosan film as immobilization matrix

A novel amperometric sensor of hydrogen peroxide was constructed. Hemoglobin (Hb) was successfully immobilized on nanometer-sized SiO2, which was supported by chitosan. Chitosan was acted as dispersant. The determination of hydrogen peroxide was performed in the presence of an electron mediator hydroquinone. Hb immobilized on the SiO2/chitosan composite film displayed excellent electrocatalytical activity to the reduction of H2O2. The linear range of detection towards H2O2 was from 6.25 x 10(-7) to 1.63 x 10(-4) mol/L with a detection limit of 1.8 x 10(-7) mol/ L (S/N = 3). The apparent Michaelis-Menten constant (K-M(app)) was found to be 0.75 mmol/ L.