IMMOBILIZATION OF BIOFUNCTIONAL SUBSTANCE AND ELECTRODE USING THE SAME

PURPOSE:To obtain a fine biosensor electrode which enables quick and highly accurate measurement, by forming a high polymer thin film to cover a porous highly conductive substance after immersion into a biofunctional substance solution. CONSTITUTION:A platinum wire is sealed into a glass tube and ground to obtain a circular fine platinum electrode. Then, this platinum electrode is immersed into a platinic acid chloride solution to attain electric precipitation of a platinum black 1. This platinum black precipitated electrode is immersed into an aqueous solution of a biofunctional substance 2 such as glucose oxidase and dried in air. The electrode is further impregnated with a high polymer substance such as albumin and heparin and made insoluble by a crosslinking agent to form an insoluble high polymer thin film 3. This enables uniform incorporation of the biofunctional substance 2 into a conducting substance fine particle 1 such as platinum black, thereby producing a highly sensitive biosensor of quick response.