title: Mediated electron transfer of cellobiose dehydrogenase and glucose oxidase at osmium polymer-modified nanoporous gold electrodes.
abstract: Nanoporous and planar gold electrodes were utilised as supports for the redox enzymes Aspergillus niger glucose oxidase (GOx) and Corynascus thermophilus cellobiose dehydrogenase (CtCDH). Electrodes modified with hydrogels containing enzyme, Os-redox polymers and the cross-linking agent poly(ethylene glycol)diglycidyl ether were used as biosensors for the determination of glucose and lactose. Limits of detection of 6.0 (±0.4), 16.0 (±0.1) and 2.0 (±0.1) μM were obtained for CtCDH-modified lactose and glucose biosensors and GOx-modified glucose biosensors, respectively, at nanoporous gold electrodes. Biofuel cells composed of GOx- and CtCDH-modified gold electrodes were utilised as anodes, together with Myrothecium verrucaria bilirubin oxidase (MvBOD) or Melanocarpus albomyces laccase as cathodes, in biofuel cells. A maximum power density of 41 μW/cm(2) was obtained for a CtCDH/MvBOD biofuel cell in 5 mM lactose and O2-saturated buffer (pH 7.4, 0.1 M phosphate, 150 mM NaCl).
authors.affiliation: Department of Chemical and Environmental Sciences, Materials and Surface Science Institute, University of Limerick, Limerick, Ireland.
authors.forename: Urszula
authors.initials: U
authors.lastname: Salaj-Kosla
authors.forename: Micheál D
authors.initials: MD
authors.lastname: Scanlon
authors.forename: Tobias
authors.initials: T
authors.lastname: Baumeister
authors.forename: Kawah
authors.initials: K
authors.lastname: Zahma
authors.forename: Roland
authors.initials: R
authors.lastname: Ludwig
authors.forename: Peter
authors.initials: P
authors.lastname: Ó Conghaile
authors.forename: Domhnall
authors.initials: D
authors.lastname: MacAodha
authors.forename: Dónal
authors.initials: D
authors.lastname: Leech
authors.forename: Edmond
authors.initials: E
authors.lastname: Magner
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology*; D001674:Bioelectric Energy Sources / Q000382:microbiology; D015374:Biosensing Techniques / Q000379:methods*; D002237:Carbohydrate Dehydrogenases / Q000737:chemistry / Q000378:metabolism*; D003432:Cross-Linking Reagents / Q000737:chemistry; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D005947:Glucose / Q000032:analysis*; D005949:Glucose Oxidase / Q000737:chemistry / Q000378:metabolism*; D006046:Gold / Q000737:chemistry; D007785:Lactose / Q000032:analysis*; D057230:Limit of Detection; D049329:Nanostructures / Q000737:chemistry; D009992:Osmium / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D020037:Sordariales / Q000201:enzymology*
chemical_list: D003432:Cross-Linking Reagents; D004800:Enzymes, Immobilized; D011108:Polymers; D009992:Osmium; D006046:Gold; D002237:Carbohydrate Dehydrogenases; D005949:Glucose Oxidase; C019859:cellobiose-quinone oxidoreductase; D005947:Glucose; D007785:Lactose