An amperometric biosensor for glucose based on electrodeposited redox polymer/glucose oxidase film on a gold electrode.

In this paper, we described a glucose biosensor based on the co-electrodeposition of a poly(vinylimidazole) complex of Os(bpy)2Cl](+/2+) (PVI-Os) and glucose oxidase (GOX) on a gold electrode surface. The one-step co-electrodeposition method provided a better control on the sensor construction, especially when it was applied to microsensor construction. The modified electrode exhibited the classical features of a kinetically fast redox couple bound to an electrode surface and the redox potential of the redox polymer/enzyme film was 0.14 V (vs. SCE). For a scan rate of up to 200 mV s(-1), the peak-to-peak potential separation was less than 25 mV. In the presence of glucose, a typical catalytic oxidation current was observed, which reached a plateau at 0.25 V (vs. SCE). Under the optimal experimental conditions, the steady-state electrooxidation current measured at 0.30 V (vs. SCE) was linear to the glucose concentration in the range of 0-30 mM. Successful attempts were made in blood sample analysis.