Biofuel Cells Composed by Using Glucose Oxidase on Chitosan Coated Carbon Fiber Cloth

This study presents a high-performance biofuel cell construction based on the covalent immobilizing of glucose oxidase (GOx) on chitosan-coated carbon cloth which is used as an anodic catalyst. The chitosan was coated by the coagulation of an aqueous chitosan solution on the carbon cloth surface. The GOx was coupled to chitosan using N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide (EDC) and N-hydroxysuccinimide (NHS) as the condensing agents. Response surface methodology (RSM) and Box-Behnken design were employed to search for the optimal conditions, and to understand the significance of the factors affecting the activity of immobilized GOx. From ridge max analysis, the optimal immobilization condition was found at a reaction time of 50 min, a pH of 5.9, and an enzyme/support ratio of 3 (w/w). Under optimal conditions, the predicted and the experimental immobilized GOx activities were 34.42±1.07 and 33.50±0.92 U g-1 support, respectively. Based on the regression model, the carbon cloth electrodes with various GOx activities were prepared, and the effect of GOx activity on the power density generated from the biofuel cell was investigated. The power density was increased with GOx activity, and the maximum power of 1.87 mW cm-2 was obtained at a cell voltage of 0.44 V.