Mesoporous TiO2 films: New catalytic electrode fabricating amperometric biosensors based on oxidases

A novel catalytic material (mesoporous TiO2 films) for the cathodic detection of hydrogen peroxide in air‐saturated aqueous solution is described. The immobilization of glucose oxidase (GOD) as enzyme model onto the TiO2 electrode provides an efficient biosensor for the amperometric detection of glucose at −0.15 V (vs. SCE). GOD molecules were immobilized in an inorganic laponite gel and cross‐linked by glutaraldehyde. The highest sensitivity and detection limit were 3.33 mAM−1 cm−2 and 15 μM, respectively. In addition different procedures of enzyme immobilization including cross‐linking with glutaraldehyde and physical entrapment in a functionalized polypyrrole film have been compared.