GLUCOSE POTENTIOMETRIC ELECTRODES BASED ON MEDIATORLESS BIOELECTROCATALYSIS - A NEW APPROACH

A potentiometric method has been developed for analysis of glucose on the basis of glucose oxidase and peroxidase co-immobilized on the surface of an electrode made of composite carbonic material. Catalytic oxidation of glucose results in the formation of hydrogen peroxide. Mediatorless peroxidase catalysis of electroreduction of hydrogen peroxide leads to a shift in the electrode potential. The rate of the increase of the electrode potential is proportional to glucose concentration and calibration curve is linear at 0.025-2.0 mM. Electrodes permit at least 100 measurements without any loss in the activity. Electrodes remain stable for 90 days when stored at 277 K.