Using extended gate field effect transistor to design and analyze the chinese medicine biosensor

摘要

In this invention, an extended gate FET with a tin dioxide membrane is applied to fabricate a berberine sensor. There are two methods for fabricating the berberine sensor. First, it is mixed by the macromolecule polymer and electrocatalytic activities. The membrane is adsorbed on the SnO₂/ITO glass and the berberine sensor is completed. Second, a polymer is used to immobilize enzyme on the substrate and detect the berberine. In this invention, the extended gate field effect transistor of the SnO₂/ITO glass is applied to fabricate a durable berberine detection electrode. One of the berberine sensors that is macromolecule polymer, the optimal measurement environment is in distilled water and the best response curve can be realized, the detection rang is from 1x10^-3M to 5x10^-7M and the linear range is about 121.47 mV/pC. The berberine sensor based on the enzyme that optimal measurement environment is in 0.1M phosphate buffer solution at pH7.4 and better response curves can be obtained. Although the detection rang is from 1x10^-3M to 1x10^-7M, the linear range is not better which is about 20.05 mV/pC.