Chen Haode, Zuo Xiaolei, Su Shao, Tang Zhuzhao, Wu Aibo, Song Shiping, Zhang Dabing, Fan Chunhai
College of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
Analyst. 2008 Sep;133(9):1182-6. doi: 10.1039/b805334k. Epub 2008 Jul 21.
There has been urgent demand for rapid, sensitive and cost-effective pesticide assay technologies due to the global attention of environmental and food-safety problems. Acetycholinesterase (AChE)-based electrochemical sensors have attracted significant interest toward this goal. In this contribution, we introduced multiwalled carbon nanotubes (MWNTs) into our sensor design, where they played dual enhancement roles; first is that MWNTs loaded on glassy carbon (GC) electrodes significantly increase surface areas, facilitating the electrochemical polymerization of prussian blue (PB), a redox mediator for the electrochemical oxidation of the enzymatic product, thiocholine (TCh). Second, MWNTs enhance the enzymatic activity of AChE, as manifested by the decreased Michaelis-Menten constant (K(m)). As a result of these two important enhancement factors offered by MWNTs, our electrochemical pesticide sensor exhibited rapid response and high sensitivity toward the detection of a series of pesticides. Moreover, we demonstrated that this sensor was stable, reproducible and selective enough for detection in real samples.
由于全球对环境和食品安全问题的关注，对快速、灵敏且经济高效的农药检测技术有着迫切需求。基于乙酰胆碱酯酶（AChE）的电化学传感器在实现这一目标方面引起了极大关注。在本研究中，我们将多壁碳纳米管（MWNTs）引入传感器设计，其发挥了双重增强作用；首先，负载在玻碳（GC）电极上的MWNTs显著增加了表面积，有利于普鲁士蓝（PB）的电化学聚合，PB是用于酶促产物硫代胆碱（TCh）电化学氧化的氧化还原介质。其次，MWNTs增强了AChE的酶活性，表现为米氏常数（K(m)）降低。由于MWNTs提供的这两个重要增强因素，我们的电化学农药传感器对一系列农药的检测表现出快速响应和高灵敏度。此外，我们证明该传感器稳定、可重复，并且对实际样品检测具有足够的选择性。
