Electrochemically fabricated nanoelectrode ensembles for glucose biosensors

Novel glucose oxidase (GOX) sensor arrays with nanoelectrode population densities of up to 1 × 1010/cm2 nanoelectrodes are reported. These nanoelectrode sensors, polypyrrole (PPy) nanofibers containing entrapped GOX, were fabricated via a two-step process, which consisted of an electroadsorption of GOX followed by an electrochemical codeposition of PPy with GOX within the nanopores of an anodic aluminum oxide (AAO) membrane. It was found by SEM observation that GOX could intercalate in PPy nanofibers, especially in the region close to their side surface. The GOX/PPy nanofiber array electrode demonstrates a good biocatalytic activity to glucose with an apparent Michaelis–Menten constant (KMapp) of 5.7 mM and a response time of about 15 s. The PPy/GOX nanofiber array electrode may have potential applications in monitoring and diagnostic tests in practical use in the future.