PLATINIZATION OF SHAPABLE ELECTROCONDUCTIVE POLYMER FILM FOR AN IMPROVED GLUCOSE SENSOR

This paper describes a novel electrode material for the preparation of a first generation amperometric biosensor. The material consists of a flexible conductive polymer film of polypyrrole doped with polyanions and a layer of microporous Pt black, prepared electrochemically on th e polymer film. Sensors fabricated with this material produce a compar atively higher H2O2 oxidation current at a lower applied potential. Gl ucose sensors were prepared by adsorbing glucose oxi dase at the porou s Pt black structure, covering with gelatin, and finally cross-linking with glutaraldehyde at dry condition. The developed sensors showed si gnificantly improved performance over similar reported sensor systems. The performance of the glucose sensor was evaluated by a specially de signed flow injection analysis (FIA) system. The sensors were continuo usly polarized at 25 degrees C and glucose samples were automatically injected at 30 min intervals. The sensors worked at 0.3 to 0.4 V and p roduced a huge current response (>1 mA/cm(2)) with a wide linear range of detection (0 to 100 mM). The system effectively recycles oxygen, t hus, the response current was not affected by a variation of oxygen co ncentration of the buffer. The interference of ascorbic acid, uric aci d, bilirubin, etc. (at a physiological level) produced a current withi n the experimental error level. The sensor showed an extended working and shelf life.