title: Membraneless glucose/oxygen enzymatic fuel cells using redox hydrogel films containing carbon nanotubes.
abstract: Co-immobilisation of three separate multiple blue copper oxygenases, a Myceliophthora thermophila laccase, a Streptomyces coelicolor laccase and a Myrothecium verrucaria bilirubin oxidase, with an [Os(2,2'-bipyridine)2 (polyvinylimidazole)10Cl](+/2+) redox polymer in the presence of multi-walled carbon nanotubes (MWCNTs) on graphite electrodes results in enzyme electrodes that produce current densities above 0.5 mA cm(-2) for oxygen reduction at an applied potential of 0 V versus Ag/AgCl. Fully enzymatic membraneless fuel cells are assembled with the oxygen-reducing enzyme electrodes connected to glucose-oxidising anodes based on co-immobilisation of glucose oxidase or a flavin adenine dinucleotide-dependent glucose dehydrogenase with an [Os(4,4'-dimethyl-2,2'-bipyridine)2(polyvinylimidazole)10Cl](+/2+) redox polymer in the presence of MWCNTs on graphite electrodes. These fuel cells can produce power densities of up to 145 μW cm(-2) on operation in pH 7.4 phosphate buffer solution at 37 °C containing 150 mM NaCl, 5 mM glucose and 0.12 mM O2. The fuel cells based on Myceliophthora thermophila laccase enzyme electrodes produce the highest power density if combined with glucose oxidase-based anodes. Although the maximum power density of a fuel cell of glucose dehydrogenase and Myceliophthora thermophila laccase enzyme electrodes decreases from 110 μW cm(-2) in buffer to 60 μW cm(-2) on testing in artificial plasma, it provides the highest power output reported to date for a fully enzymatic glucose-oxidising, oxygen-reducing fuel cell in artificial plasma.
authors.affiliation: School of Chemistry & Ryan Institute, National University of Ireland Galway, University Road, Galway, Ireland.
authors.forename: Domhnall
authors.initials: D
authors.lastname: MacAodha
authors.forename: Peter
authors.initials: P
authors.lastname: Ó Conghaile
authors.forename: Brenda
authors.initials: B
authors.lastname: Egan
authors.forename: Paul
authors.initials: P
authors.lastname: Kavanagh
authors.forename: Dónal
authors.initials: D
authors.lastname: Leech
mesh_terms: D001203:Ascomycota / Q000201:enzymology; D001674:Bioelectric Energy Sources; D004566:Electrodes; D005947:Glucose / Q000737:chemistry / Q000378:metabolism*; D042843:Glucose 1-Dehydrogenase / Q000378:metabolism; D005949:Glucose Oxidase / Q000378:metabolism; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry / Q000378:metabolism*; D042845:Laccase / Q000378:metabolism; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry / Q000378:metabolism; D010084:Oxidation-Reduction; D044925:Oxidoreductases Acting on CH-CH Group Donors / Q000378:metabolism; D010100:Oxygen / Q000737:chemistry / Q000378:metabolism*; D048372:Streptomyces coelicolor / Q000201:enzymology
chemical_list: D037742:Nanotubes, Carbon; D009942:Organometallic Compounds; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D042843:Glucose 1-Dehydrogenase; D005949:Glucose Oxidase; D042845:Laccase; D044925:Oxidoreductases Acting on CH-CH Group Donors; C042401:bilirubin oxidase; D005947:Glucose; D010100:Oxygen
keywords: enzyme electrodes; fuel cells; glucose oxidation; oxygen reduction; redox chemistry