摘要
植物水解酶催化α-乙酸萘酯水解生成α-萘酚，α-萘酚与三氯化铁溶液发生显色反应生成紫色络合物，该络合物最大吸光度位于516nm波长处。而此显色反应因有机膦农药的存在而受到抑制，有机膦农药的质量浓度与吸光度的下降程度（△A）呈线性关系，据此建立了植物水解酶催化-分光光度法快速测定痕量有机膦农药的方法。对反应的温度、反应时间和缓冲溶液的pH值等因素进行了试验并予以优化。敌敌畏、敌百虫、甲胺膦、乐果和水胺硫膦等有机膦农药的检出限（3S／N）在0．001～0．25mg·L^-1范围内，相对标准偏差（n=6）均小于5．5％。所提出的方法应用于蔬菜中有机膦农药的测定，加标回收率在87．0％～93．0％之间。
The hydrolysis of α-naphthyl acetate was catalyzed with plant-esterase, and α-naphthol was obtained. A purple complex was formed by the color reaction of α-naphthol with FeCl3, with its absorption maximum at the wavelength of 516 nm. The color reaction was inhibitated by the presence of organo-phosphorus pesticides, and linear relationship between mass concentration of organo-phosphorus pesticides and decrease of absorbance （△A） was obtained. Based on these facts, a method for rapid determination of organo-phosphorus pesticides was proposed. Experimental conditions, including reaction temperature, reaction time, pH of buffer solution and interference of co-existing ions, were studied and optimized. Detection limits （3S/N） of dichlorophos, dipterex, methamidophos, dimethoate and isocarbophos were in the range of 0. 001-0. 25 mg · L^-1 , and RSD＇s （n =6） found for these pesticides were tess than 5. 5%. The method was used in the analysis of vegetables, values of recovery found by standard addition method were in the range of 87. 0%-93.0%.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2009年第5期531-532,536,共3页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
关键词
植物水解酶
分光光度法
有机膦农药
Plant-hydrolases Speetrophotometry
Organo-phosphorus pesticides
