基于有机磷农药对乙酰胆碱酯酶(Acetylcholinesterase,AChE)的抑制作用,用金纳米粒子(Au nanoparticles,AuNPs)与壳聚糖/SiO2杂化溶胶-凝胶构成复合固酶基质,将AChE固定于玻碳电极表面,制备了电流型AChE生物传感器选用久效磷进行实验,以氯化硫代乙酰胆碱为底物,建立了电化学测定有机磷农药的分析方法.依据传感器的电流响应值,优化了各种实验条件.该传感器对久效磷进行检测的线性响应范围为0.5～12.0μg/mL,检出限为0 02 μg/mL.传感器具有良好的重现性和稳定性,为有机磷农药的检测提供了一种简便易行的方法.%Based on the inhibition effects of organophosphorus pesticides on acetylcholinesterase( AChE) , an amperomerometric biosensor was developed by immobilizing AChE on glassy carbon electrode with the composite film of Au nanoparticals and chitosan-silica hybrid sol-gel. Using acetylthiocholine chloride as the substrate , the electrochemical determination method for organophosphorus pesticide was established with monocro-tophos as a representative model for sensitivity tests. The experimental conditions were optimized according to the current response. The response of biosensor fabricated was related linearly to the concentration of monocro-tophos in the range of 0.5-12. 0 μg/mL with a detection limit of 0.02 μg/mL. The developed biosensor exhibited good reproducibility and acceptable stability, providing a simple method for the analysis of organophosphorus pesticide.
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