TY  - JOUR
A1  - Tadjoung Waffo, Armel Franklin
A1  - Mitrova, Biljana
A1  - Tiedemann, Kim
A1  - Iobbi-Nivol, Chantal
A1  - Leimkühler, Silke
A1  - Wollenberger, Ulla
T1  - Electrochemical trimethylamine n-oxide biosensor with enzyme-based oxygen-scavenging membrane for long-term operation under ambient air
T2  - Biosensors : open access journal
N2  - An amperometric trimethylamine N-oxide (TMAO) biosensor is reported, where TMAO reductase (TorA) and glucose oxidase (GOD) and catalase (Cat) were immobilized on the electrode surface, enabling measurements of mediated enzymatic TMAO reduction at low potential under ambient air conditions. The oxygen anti-interference membrane composed of GOD, Cat and polyvinyl alcohol (PVA) hydrogel, together with glucose concentration, was optimized until the O-2 reduction current of a Clark-type electrode was completely suppressed for at least 3 h. For the preparation of the TMAO biosensor, Escherichia coli TorA was purified under anaerobic conditions and immobilized on the surface of a carbon electrode and covered by the optimized O-2 scavenging membrane. The TMAO sensor operates at a potential of -0.8 V vs. Ag/AgCl (1 M KCl), where the reduction of methylviologen (MV) is recorded. The sensor signal depends linearly on TMAO concentrations between 2 mu M and 15 mM, with a sensitivity of 2.75 +/- 1.7 mu A/mM. The developed biosensor is characterized by a response time of about 33 s and an operational stability over 3 weeks. Furthermore, measurements of TMAO concentration were performed in 10% human serum, where the lowest detectable concentration is of 10 mu M TMAO.
KW  - trimethylamine N-oxide
KW  - biosensor
KW  - TMAO-reductase
KW  - oxygen scavenger
KW  - immobilized enzyme
KW  - multienzyme electrode
KW  - viologen
Y1  - 2021
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/62821
SN  - 2079-6374
VL  - 11
IS  - 4
PB  - MDPI
CY  - Basel
ER  -