LAYER-LAYER ASSEMBLY FOR EXTREMELY STABLE GLUCOSE SENSORS

A novel fabrication of an amperometric glucose sensor by layer after l ayer approach is described. The sensor electrode is fabricated by arra nging a layer of Pt black, a layer of glucose oxidase (GOD) and a laye r of stabilizer gelatin on a shapable electro-conductive (SEC) film su rface. Finally, the dried layered-assembly is cross-linked by exposing to a diluted glutaraldehyde solution. The performance of the develope d sensor is evaluated by a FIA system at 37 degrees C and under a cont inuous polarization at 0.4 V (vs. Ag/AgCl). The sensitivity of the sen sor was dependent on the amount of GOD loaded. The highest sensitivity (3.6 mu A/mM cm(-2)) of the sensor was obtained at a GOD loading of 1 60 mu g/cm(2), and the linear dynamic range was extended to 80mM level when the sensor was covered with a polycarbonate membrane. The sensor shows an extremely stable response for several weeks and a storage st ability of over 2 years.