title: Kinetic limitations of a bioelectrochemical electrode using carbon nanotube-attached glucose oxidase for biofuel cells.
abstract: Carbon nanotubes (CNTs) have been used for various bioelectrochemical applications, presumably for substantial improvement in performance. However, often only moderate results observed, with many governing factors have been considered and suggested yet without much systematic evaluation and verification. In this study, CNT-supported glucose oxidase (CNT-GOx) was examined in the presence of 1,4-benzoquinone (BQ). The intrinsic Michaelis parameters of the reaction catalyzed by CNT-GOx were found very close to those of native GOx. However, the Nafion entrapment of CNT-GOx for an electrode resulted in a much lower activity due to the limited availability of the embedded enzyme. Interestingly, kinetic studies revealed that the biofuel cell employing such an enzyme electrode only generated a power density equivalent to <40% of the reaction capability of the enzyme on electrode. It appeared to us that factors such as electron and proton transfer resistances can be more overwhelming than the heterogeneous reaction kinetics in limiting the power generation of such biofuel cells.
authors: Department of Bioproducts and Biosystems Engineering, Biotechnology Institute, University of Minnesota, St. Paul, 55108, USA.
authors: Xueyan
authors: X
authors: Zhao
authors: Hongfei
authors: H
authors: Jia
authors: Jungbae
authors: J
authors: Kim
authors: Ping
authors: P
authors: Wang
mesh_terms: D016227:Benzoquinones / Q000378:metabolism; D001674:Bioelectric Energy Sources; D004560:Electricity; D004566:Electrodes; D005949:Glucose Oxidase / Q000378:metabolism*; D007700:Kinetics; D037742:Nanotubes, Carbon
chemical_list: D016227:Benzoquinones; D037742:Nanotubes, Carbon; C004532:quinone; D005949:Glucose Oxidase