GLUCOSE SENSITIVITY OF POLYPYRROLE FILMS CONTAINING IMMOBILIZED GLUCOSE-OXIDASE AND HYDROQUINONESULFONATE IONS

Glucose oxidase (GOx) and hydroquinonesulfonate ions (HQS) were incorporated into polypyrrole by electropolymerization of pyrrole in the presence of these substances. The resulting polymer films showed sensitivities to glucose when no mediator was used in solution, the magnitude of the sensitivity being influenced by the concentration of HQS at a fixed concentration of GOx. The amount of immobilized HQS and GOx was proportional to the deposition charge of the polypyrrole films, but there was an optimum deposition charge to achieve the highest sensitivity. In the deposition charges that were less than the optimum value, the sensitivity seems to be determined by the amount of incorporated glucose oxidase and hydroquinonesulfonate ions, and beyond the optimal value, the sensitivity seems to be controlled by the diffusion of glucose in the polymer film. Absorption spectra and fluorescence spectra measurements of HQS and GOx in the deposition bath suggested that HQS adsorbs on GOx in such a way as to allow electronic interaction between each other.