Enzyme modified microband electrodes: cross-talk effects and their elimination

Abstract

One microband of an array of four microband electrodes (1 mm long and 25 μm wide with a 25 μm gap) was modified with glucose oxidase by direct electrochemically assisted immobilisation, giving a stable microbiosensor with an apparent Michaelis–Menten constant of 12 mM and an i_max of 80 nA. Cross-talk effects on the adjacent microbands were studied and three different methods for their elimination were tested; the most efficient one involved catalase deposition on the adjacent microband. Under these conditions, the maximum response at the unmodified microbands was in the worst case about 3% compared with the response of the modified microband. This approach has the potential to fabricate a multianalyte microbiosensor.