酶抑制法两种底物优越性比较试验

Comparison experiment on the advantages of two different substrates in enzyme inhibition

酶抑制法是根据农药对酯酶的抑制率与样品中有机磷农药浓度的对数成正比关系,来定量分析有机磷农药残留量。酶抑制法常用的底物有2,6-二氯靛酚乙酸酯和固兰B盐,通过对这两种底物的优越性进行比较试验,结果表明:2,6-二氯靛酚乙酸酯较固兰B盐更优越,更适合于有机磷农药的快速现场检测。2,6-二氯靛酚乙酸酯作为底物的优越性主要表现在:与生成物有良好的稳定性;植物酯酶的反应条件较为协调合理;敌敌畏对植物酯酶的抑制率与农药浓度对数值呈良好的线性关系;用添加农药法测定的回收率较高。

Enzyme inhibition is used for quantitatively analyzing the organophosphorus pesticide residues according to the proportional relationship between the inhibitory rate of pesticide to esterase and the logarithms of organophosphorus pesticide concentration in samples. In general, 2,6-dichloro-benzennone--Indopheny-lacetate and fast blue B salt are usually used as substrates in enzyme inhibition. Through comparing the advantages of two sub. strates ,the results confirmed that 2,6-dichloro-benzenone-indopheny-lacetate was better than fast blue B salt used as the substrate in pesticide residue onsite rapid detection. As compared with fast blue B salt, the advantages of 2, 6.dichloro.-benzennone-indopheny--lacetate mainly include its better stability of products, and more optional and reasonable reaction conditions needed for plant esterase. There is good linear correlation between the inhibitory rate of DDVP on plant esterase and the logarithmic value of pesticide concentration, and the recovery is higher by adding pesticide method.