Glucose sensing based on interdigitated array microelectrode.

A micro glucose sensor consisting of an interdigitated array gold microelectrode was developed. The interdigitated array structure, which has 10 microns band width and 10 microns band gap, was fabricated in a small region (2.5 x 5 mm2) on a quartz substrate. Glucose oxidase was chemically fixed onto the electrode surface through self-assembled monolayer of 11-mercaptoundecanoic acid; ferroceneacetic acid was used as electron mediator. Electrochemical properties of the glucose oxidase-immobilized microelectrode were investigated by cyclic voltammogram measurements. Results confirmed that the reductive ferroceneacetic acid generated at counter electrode diffuses through a narrow band gap (10 microns) and can reach the working electrode surface.