鸭血清胆碱酯酶抑制法检测果蔬农药残留的研究

对农药残留快速检测方法——胆碱酯酶抑制法进行了研究。以二次盐析后的鸭血清丁酰胆碱酯酶(BChE)为农药残留的检测用酶,碘化硫代丁酰胆碱(BTChI)为底物,5-5'-二硫代-二硝基苯甲酸(DTNB)为显色剂,410nm比色测定吸光值变化,计算胆碱酯酶的抑制率,从而推算农药残留情况。当抑制率大于35%时,表明农药含量超标。检测过程只需20～40min,可同时检测多个样品,与气相色谱检测结果的符合率大于85%。

Study on the Enzyme Inhibition Method of Pesticide Residues with Cholinesterase from Duck Serum

The enzyme inhibition method of pesticide residues has been developed. In the reaction system, A BChE from duck serum which was purified by salting was selected to determine pesticide residues, S-butyrylthiocholine iodide was substrate and 5,5’-dithiobis (2-nitrobenzoic acid) was chromogenic agent. By calculating inhibition rate of ChE activity, the condition for pesticide residues could be estimated. The standard of detection was a dosage of inhibiting 35% of ChE activity. When the inhibition rate was higher than 35%, it indicated that the sample had excessive pesticide residues. The detection time was 20~40min, and several samples can be determined at the same time. The coincidence extent of colorimetry and gas chromatography is above 85%.