Flexible glucose sensor with a film-type oxygen electrode by microfabrication techniques

The glucose sensor (width: 3 mm) was constructed by immobilizing glucose oxidase (GOD) with glutaraldehyde solution onto the sensitive area of the film-type oxygen electrode. The oxygen electrode was fabricated by sealing KCI electrolyte solution in a reaction cell with metal-weldable film and gas-permeable membrane which was coated with Pt working electrode and Ag/AgCl counter/reference electrode by microfabrication techniques such as sputtering, photolithography process, etc. The sensor behavior was evaluated using standard glucose solutions in a batch measurement system with a computer-controlled potentiostat at a reduction potential of -700 mV vs. Ag/AgCl. The sensor device has thinner and flexible structure. The sensor was possible to be used for measuring glucose from 0.02 to 0.98 mmol/l (coefficient of correlation: 0.999), including the reported concentration of tear glucose in normal (0.14 mmol/l).