(481c) Carbon Nanotube Modified Microfiber Electrode as Support for Glucose Oxidation Bioanodes

Nanotube-coated carbon paper porous electrodes have previously been applied to biofuel cells to achieve high current densities. To study the transport and kinetics within the porous electrode volume, it is desirable to fabricate a carbon fiber microelectrode (CFME) to mimic the micro-environment of a single fiber in the carbon paper. CFMEs were fabricated by sealing a carbon fiber within a glass capillary, and coated with carboxylated CNT and biocatalytic hydrogel comprising glucose oxidase, crosslinker, and electron mediator PVI-[Os(bipyridine)2Cl]+/2+. Roughly doubling the diameter of the 7 µm fiber by application of nanotubes led to more than 100-fold increase in surface area as measured by capacitance, and 6.4 fold increase in oxidation current density. This CNT/CFME system is a promising platform for characterization of high surface area supports for bioelectrodes.