title: Enzyme precipitate coatings of glucose oxidase onto carbon paper for biofuel cell applications.
abstract: Enzymatic biofuel cells (BFC) have a great potential as a small power source, but their practical applications are being hampered by short lifetime and low power density. This study describes the direct immobilization of glucose oxidase (GOx) onto the carbon paper in the form of highly stable and active enzyme precipitation coatings (EPCs), which can improve the lifetime and power density of BFCs. EPCs were fabricated directly onto the carbon paper via a three-step process: covalent attachment (CA), enzyme precipitation, and chemical crosslinking. GOx-immobilized carbon papers via the CA and EPC approaches were used as an enzyme anode and their electrochemical activities were tested under the BFC-operating mode. The BFCs with CA and EPC enzyme anodes produced the maximum power densities of 50 and 250 µW/cm(2) , respectively. The BFC with the EPC enzyme anode showed a stable current density output of >700 µA/cm(2) at 0.18 V under continuous operation for over 45 h. When a maple syrup was used as a fuel under ambient conditions, it also produced a stable current density of >10 µA/cm(2) at 0.18 V for over 25 h. It is anticipated that the direct immobilization of EPC on hierarchical-structured electrodes with a large surface area would further improve the power density of BFCs that can make their applications more feasible.
authors: Chemical Engineering Department, Washington State University, Pullman, Washington 99164-2710, USA.
authors: Mike
authors: M
authors: Fischback
authors: Ki Young
authors: KY
authors: Kwon
authors: Inseon
authors: I
authors: Lee
authors: Su Jeong
authors: SJ
authors: Shin
authors: Hyun Gyu
authors: HG
authors: Park
authors: Byoung Chan
authors: BC
authors: Kim
authors: Yongchai
authors: Y
authors: Kwon
authors: Hee-Tae
authors: HT
authors: Jung
authors: Jungbae
authors: J
authors: Kim
authors: Su
authors: S
authors: Ha
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology; D001674:Bioelectric Energy Sources; D001709:Biotechnology / Q000295:instrumentation*; D002244:Carbon / Q000737:chemistry*; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism; D004867:Equipment Design; D005656:Fungal Proteins / Q000737:chemistry / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D005949:Glucose Oxidase / Q000737:chemistry* / Q000378:metabolism; D010209:Paper
chemical_list: D004800:Enzymes, Immobilized; D005656:Fungal Proteins; D002244:Carbon; D005949:Glucose Oxidase; D005947:Glucose