TY  - JOUR
A1  - Badalyan, Artavazd
A1  - Neumann-Schaal, Meina
A1  - Leimkühler, Silke
A1  - Wollenberger, Ursula
T1  - A Biosensor for aromatic aldehydes comprising the mediator dependent PaoABC-Aldehyde oxidoreductase
JF  - Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis
N2  - A novel aldehyde oxidoreductase (PaoABC) from Escherichia coli was utilized for the development of an oxygen insensitive biosensor for benzaldehyde. The enzyme was immobilized in polyvinyl alcohol and currents were measured for aldehyde oxidation with different one and two electron mediators with the highest sensitivity for benzaldehyde in the presence of hexacyanoferrate(III). The benzaldehyde biosensor was optimized with respect to mediator concentration, enzyme loading and pH using potassium hexacyanoferrate(III). The linear measuring range is between 0.5200 mu M benzaldehyde. In correspondence with the substrate selectivity of the enzyme in solution the biosensor revealed a preference for aromatic aldehydes and less effective conversion of aliphatic aldehydes. The biosensor is oxygen independent, which is a particularly attractive feature for application. The biosensor can be applied to detect contaminations with benzaldehyde in solvents such as benzyl alcohol, where traces of benzaldehyde in benzyl alcohol down to 0.0042?% can be detected.
KW  - Aldehyde oxidoreductase
KW  - Benzaldehyde
KW  - Biosensor
KW  - Aromatic aldehydes
KW  - Molybdenum cofactor
Y1  - 2013
U6  - https://doi.org/10.1002/elan.201200362
SN  - 1040-0397
VL  - 25
IS  - 1
SP  - 101
EP  - 108
PB  - Wiley-VCH
CY  - Weinheim
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  -