当前位置: X-MOL 学术ChemElectroChem › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Trimethylamine N‐Oxide Electrochemical Biosensor with a Chimeric Enzyme
ChemElectroChem ( IF 4 ) Pub Date : 2018-12-07 , DOI: 10.1002/celc.201801422
Biljana Mitrova 1 , Armel F. T. Waffo 1 , Paul Kaufmann 1 , Chantal Iobbi‐Nivol 2 , Silke Leimkühler 1 , Ulla Wollenberger 1
Affiliation  

For the first time, an enzyme‐based electrochemical biosensor system for determination of trimethylamine N‐oxide (TMAO) is described. It employs an active chimeric variant of TorA in combination with an enzymatically deoxygenating system and a low‐potential mediator for effective regeneration of the enzyme and cathodic current generation. TMAO reductase (TorA) is a molybdoenzyme found in marine and most enterobacteria that specifically catalyzes the reduction of TMAO to trimethylamine (TMA). The chimeric TorA, named TorA‐FDH, corresponds to the apoform of TorA from Escherichia coli reconstituted with the molybdenum cofactor from formate dehydrogenase (FDH). Each enzyme, TorA and TorA‐FDH, was immobilized on the surface of a carbon electrode and protected with a dialysis membrane. The biosensor operates at an applied potential of −0.8 V [vs. Ag/AgCl (1 M KCl)] under ambient air conditions thanks to an additional enzymatic O2‐scavenger system. A comparison between the two enzymatic sensors revealed a much higher sensitivity for the biosensor with immobilized TorA‐FDH. This biosensor exhibits a sensitivity of 14.16 nA/μM TMAO in a useful measuring range of 2–110 μM with a detection limit of LOD=2.96 nM (S/N=3), and was similar for TMAO in buffer and in spiked serum samples. With a response time of 16±2 s, the biosensor is stable over prolonged daily measurements (n=20). This electrochemical biosensor provides suitable applications in detecting TMAO levels in human serum.

中文翻译:

具有嵌合酶的三甲胺N-氧化物电化学生物传感器

首次描述了用于测定三甲胺N-氧化物(TMAO)的基于酶的电化学生物传感器系统。它结合了酶脱氧系统和低电势介体,结合了活性的TorA嵌合变异体和Tora,可有效地再生酶和产生阴极电流。TMAO还原酶(TorA)是在海洋细菌和大多数肠杆菌中发现的一种钼酶,可特异性催化TMAO还原为三甲胺(TMA)。嵌合的TorA,称为TorA-FDH,对应于大肠杆菌中TorA的无形体用甲酸脱氢酶(FDH)中的钼辅助因子进行重组。每种酶TorA和TorA-FDH被固定在碳电极表面并用透析膜保护。生物传感器在-0.8 V [vs.的施加电势下运行。Ag / AgCl(1 M KCl)]在环境空气条件下归功于额外的酶促O 2清除剂系统。两种酶传感器之间的比较显示,固定化TorA-FDH的生物传感器具有更高的灵敏度。这种生物传感器在2–110μM的有效测量范围内显示出14.16 nA /μMTMAO的灵敏度,LOD = 2.96 nM(S / N = 3)的检测极限,与TMAO在缓冲液和加标血清样品中的相似。生物传感器的响应时间为16±2 s,在长时间的日常测量中保持稳定(n= 20)。该电化学生物传感器为检测人血清中的TMAO水平提供了合适的应用。
更新日期:2018-12-07
down
wechat
bug