title: 3D-electrode architectures for enhanced direct bioelectrocatalysis of pyrroloquinoline quinone-dependent glucose dehydrogenase.
abstract: We report on the fabrication of a complex electrode architecture for efficient direct bioelectrocatalysis. In the developed procedure, the redox enzyme pyrroloquinoline quinone-dependent glucose dehydrogenase entrapped in a sulfonated polyaniline [poly(2-methoxyaniline-5-sulfonic acid)-co-aniline] was immobilized on macroporous indium tin oxide (macroITO) electrodes. The use of the 3D-conducting scaffold with a large surface area in combination with the conductive polymer enables immobilization of large amounts of enzyme and its efficient communication with the electrode, leading to enhanced direct bioelectrocatalysis. In the presence of glucose, the fabricated bioelectrodes show an exceptionally high direct bioelectrocatalytical response without any additional mediator. The catalytic current is increased more than 200-fold compared to planar ITO electrodes. Together with a high long-term stability (the current response is maintained for >90% of the initial value even after 2 weeks of storage), the transparent 3D macroITO structure with a conductive polymer represents a valuable basis for the construction of highly efficient bioelectronic units, which are useful as indicators for processes liberating glucose and allowing optical and electrochemical transduction.
authors.affiliation: Biosystems Technology, Institute for Applied Life Sciences, Technical University of Applied Sciences Wildau , Hochschulring 1, D-15745 Wildau, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Sarauli
authors.forename: Kristina
authors.initials: K
authors.lastname: Peters
authors.forename: Chenggang
authors.initials: C
authors.lastname: Xu
authors.forename: Burkhard
authors.initials: B
authors.lastname: Schulz
authors.forename: Dina
authors.initials: D
authors.lastname: Fattakhova-Rohlfing
authors.forename: Fred
authors.initials: F
authors.lastname: Lisdat
mesh_terms: D055162:Biocatalysis; D004560:Electricity; D055664:Electrochemical Techniques; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D005947:Glucose / Q000378:metabolism; D005948:Glucose Dehydrogenases / Q000378:metabolism*; D010084:Oxidation-Reduction; D016062:Porosity; D013056:Spectrophotometry, Ultraviolet; D017971:Tin Compounds / Q000737:chemistry
chemical_list: D017971:Tin Compounds; C109984:indium tin oxide; D005948:Glucose Dehydrogenases; C033955:glucose dehydrogenase (pyrroloquinoline-quinone); D005947:Glucose
keywords: 3D electrode structures; PQQ-GDH; bioelectrochemistry; conductive polymer; direct bioelectrocatalysis; macroITO