Cai Jian-Rong, Zhou Li-Na, Han En
School of Food and Biological Engineering, Jiangsu University.
Anal Sci. 2014;30(6):669-73. doi: 10.2116/analsci.30.669.
A sensitive biosensor based on acetylcholinesterase (AChE) and carbon nanosphere (CNS) immobilized on a glassy carbon electrode was developed for the detection of pesticides by the inhibition of AChE activity. The inhibition effect of the pesticides resulted in a decrease of current response of the acetylthiocholine chloride that was used as a substrate to obtain an electrochemical signal. When applied to the pesticides carbofuran and fenitrothion, the designed biosensor exhibited high sensitivity and low detection limits. The inhibition ratio of carbofuran and fenitrothion were linearly proportional to their concentrations ranging from 0.40 to 4.79 and 6.26 to 125.31 μg/L, respectively. The theoretical detection limits were found to be 0.082 μg/L for carbofuran and 2.61 μg/L for fenitrothion. Furthermore, as the biosensor offers good reproducibility and stability, it could be used for trace detection of pesticides in real samples. Compared with other AChE biosensors, the proposed biosensor was convenient and it exhibited extreme sensitivity to pesticides.
一种基于固定在玻碳电极上的乙酰胆碱酯酶（AChE）和碳纳米球（CNS）的灵敏生物传感器被开发用于通过抑制AChE活性来检测农药。农药的抑制作用导致用作底物以获得电化学信号的氯化乙酰硫代胆碱的电流响应降低。当应用于农药克百威和杀螟硫磷时，所设计的生物传感器表现出高灵敏度和低检测限。克百威和杀螟硫磷的抑制率分别与其浓度在0.40至4.79μg/L和6.26至125.31μg/L范围内呈线性比例关系。发现克百威的理论检测限为0.082μg/L，杀螟硫磷的理论检测限为2.61μg/L。此外，由于该生物传感器具有良好的重现性和稳定性，它可用于实际样品中农药的痕量检测。与其他AChE生物传感器相比，所提出的生物传感器操作方便且对农药表现出极高的灵敏度。
