TY  - JOUR
A1  - Sarauli, David
A1  - Xu, Chenggang
A1  - Dietzel, Birgit
A1  - Schulz, Burkhard
A1  - Lisdat, Fred
T1  - Differently substituted sulfonated polyanilines - the role of polymer compositions in electron transfer with pyrroloquinoline quinone-dependent glucose dehydrogenase
JF  - Acta biomaterialia
N2  - Sulfonated polyanilines have become promising building blocks in the construction of biosensors, and therefore we use here differently substituted polymer forms to investigate the role of their structural composition and properties in achieving a direct electron transfer with the redox enzyme pyrroloquinoline quinone-dependent glucose dehydrogenase (PQQ-GDH). To this end, new copolymers containing different ratios of 2-methoxyaniline-5-sulfonic acid (MAS), 3-aminobenzenesulfonic acid (ABS) and 3-aminobenzoic acid (AB) units have been chemically synthesized. All polymers have been studied with respect to their ability to react directly with PQQ-GDH. This interaction has been monitored initially in solution, and subsequently on electrode surfaces. The results show that only copolymers with MAS and aniline units can directly react with PQQ-GDH in solution; the background can be mainly ascribed to the emeraldine salt redox state of the polymer, allowing rather easy reduction. However, when polymers and the enzyme are immobilized on the surface of carbon nanotube-containing electrodes, direct bioelectrocatalysis is also feasible in the case of copolymers composed of ABS/AB and MAS/AB units, existing initially in pernigraniline base form. This verifies that a productive interaction of the enzyme with differently substituted polymers is feasible when the electrode potential can be used to drive the reaction towards the oxidation of the substrate-reduced enzyme. These results clearly demonstrate that enzyme electrodes based on sulfonated polyanilines and direct bioelectrocatalysis can be successfully constructed.
KW  - Sulfonated polyaniline
KW  - PQQ-dependent glucose dehydrogenase
KW  - Direct electron transfer
KW  - Immobilization
KW  - Bioelectrocatalysis
Y1  - 2013
U6  - https://doi.org/10.1016/j.actbio.2013.06.008
SN  - 1742-7061
VL  - 9
IS  - 9
SP  - 8290
EP  - 8298
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Frasca, Stefano
A1  - Milan, Anabel Molero
A1  - Guiet, Amandine
A1  - Goebel, Caren
A1  - Perez-Caballero, Fernando
A1  - Stiba, Konstanze
A1  - Leimkühler, Silke
A1  - Fischer, Anna
A1  - Wollenberger, Ursula
T1  - Bioelectrocatalysis at mesoporous antimony doped tin oxide
 electrodes-Electrochemical characterization and direct enzyme
 communication
JF  - ELECTROCHIMICA ACTA
N2  - In this paper we report immobilization and bioelectrocatalysis of human sulfite oxidase (hSO) on nanostructured antimony doped tin oxide (ATO) thin film electrodes. Two types of ATO thin film electrodes were prepared via evaporation induced self-assembly of ATO nanoparticle sols. The use of a porogen results in different porosity and film thickness. Nevertheless both electrode types reveal similar quasi reversible electrochemical behavior for positive and negatively charged small mediators. Facile and durable immobilization of catalytically active enzyme in a direct electron transfer configuration was achieved without further chemical modification of the ATO surfaces. Interestingly, the binding of hSO onto the ATO surface seems to be not only of electrostatic nature, but also originates from a strong interaction between the histidine-tag of the enzyme and the supporting material. This is suggested from stable sulfite dependent bioelectrocatalytic signals at high ionic strength and imidazole desorption experiments. As such, ATO appears as a promising conductive platform for the immobilization of complex enzymes and their application in bioelectrocatalysis. (C) 2013 Elsevier Ltd. All rights reserved.
KW  - Antimony doped tin dioxide
KW  - Sulfite oxidase
KW  - Direct electrochemistry
KW  - Biosensor
KW  - Bioelectrocatalysis
Y1  - 2013
U6  - https://doi.org/10.1016/j.electacta.2013.03.144
SN  - 0013-4686
SN  - 1873-3859
VL  - 110
IS  - 2
SP  - 172
EP  - 180
PB  - PERGAMON-ELSEVIER SCIENCE LTD
CY  - OXFORD
ER  -