Employing FAD-dependent glucose dehydrogenase within a glucose/oxygen enzymatic fuel cell operating in human serum

Abstract

Flavin adenine dinucleotide-dependent glucose dehydrogenase (FAD-GDH) is emerging as an oxygen-insensitive alternative to glucose oxidase (GOx) as the biocatalyst for bioelectrodes and bioanodes in glucose sensing and glucose enzymatic fuel cells (EFCs). Glucose EFCs, which utilize oxygen as the oxidant and final electron acceptor, have the added benefit of being able to be implanted within living hosts. These can then produce electrical energy from physiological glucose concentrations and power internal or external devices. EFCs were prepared with FAD-GDH and bilirubin oxidase (BOx) to evaluate the suitability of FAD-GDH within an implantable setting. Maximum current and power densities of 186.6±7.1μAcm−2 and 39.5±1.3μWcm−2 were observed when operating in human serum at 21°C, which increased to 285.7±31.3μAcm−2 and 57.5±5.4μWcm−2 at 37°C. Although good stability was observed with continual near-optimal operation of the EFCs in human serum at 21°C for 24h, device failure was observed between 13–14h when continually operated at 37°C.