Bienzyme sensors based on poly(anilinomethylferrocene)‐modified electrodes

Amperometric bienzyme electrodes for glucose, lactic acid and glutamic acid were constructed using glucose oxidase, lactate oxidase and glutamate oxidase immobilized on a horseradish peroxidase‐poly(anilinomethylferrocene)‐modified glassy carbon electrode. In these bienzyme sensors hydrogen peroxide formed by the enzymatic reaction of glucose, lactic acid and glutamic acid with oxygen in presence of the appropriate enzyme was detected at −50 mV (vs. Ag/AgCl), by the horseradish peroxidase‐poly(anilinomethy1ferrocene)‐modified glassy carbon electrode. Because of the detection at a low applied potential, electroactive compounds such as ascorbic acid, uric acid and acetaminophen, did not interfere in analyses. The results of characterization studies of these bienzyme electrodes in terms of their, sensitivity, selectivity, linear detection range, precision, accuracy, operational lifetime stability, and long term storage stability are presented.