Glucose oxidase progressively lowers bilirubin oxidase bioelectrocatalytic cathode performance in single-compartment glucose/oxygen biological fuel cells

• Published in: Electrochimica acta Vol. 140; pp. 59 - 64
• Main Authors: Milton, Ross D., Giroud, Fabien, Thumser, Alfred E., Minteer, Shelley D., Slade, Robert C.T.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 10.09.2014
• Subjects: Bilirubin oxidase; Direct electron transfer; FAD-dependent glucose dehydrogenase; Glucose oxidase; Hydrogen peroxide; Glucose oxidase; Direct electron transfer; Hydrogen peroxide; Bilirubin oxidase; FAD-dependent glucose dehydrogenase
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2014.02.058

Enzymatic biological fuel cells (E-BFCs) were prepared using glucose oxidase (GOx) or FAD-dependent glucose dehydrogenase (FAD-GDH) as the anodic enzyme, coupled with direct electrocatalytic bilirubin oxidase (BOd) biocathodes obtained via incorporation of anthracene-modified multi-walled carbon nanotubes (Ac-MWCNTs). For GOx/BOd E-BFCs operating at pH 6.5 (200mM glucose), open-circuit potentials, maximum current densities and maximum power densities of 0.47±0.02V, 332.7±19.6μAcm−2, and 46.5±2.8μWcm−2 were observed. For FAD-GDH/BOd E-BFCs operating in the same conditions, open-circuit potentials, maximum current densities and maximum power densities of 0.40±0.01V, 226.6±8.0μAcm−2, and 35.9±1.3μWcm−2 were observed. The effect of H2O2 (as produced by the enzymatic side-reaction of GOx) on BOd bioelectrocatalytic cathodes in E-BFCs was also investigated. Short-term testing (steady state) revealed that GOx did not produce significant quantities of H2O2 to affect BOd biocathodes. However, long-term testing (steady state, 24hours) revealed that the quantity of H2O2 produced by GOx is large enough to have detrimental effects on the performance of the E-BFCs.