ENZYME NANOBAND ELECTRODES

Enzyme nanoelectrodes have been constructed by immobilizing glucose ox idase, alcohol oxidase or tyrosinase onto ultrathin carbon films (of 3 5-50 nm thickness). The enzyme immobilization is accomplished via entr apment within electropolymerized poly(o-phenylenediamine) coatings. Cy clic voltammetry and controlled-potential amperometry are used to char acterize the performance of the new nanoscopic biosensors under differ ent preparation and operation conditions. The resulting electrodes off er convenient and rapid measurements of millimolar substrate concentra tions, and (to the best of our knowledge) are the smallest enzyme prob es reported to date.