高效液相色谱柱后衍生法测定谷物中9种氨基甲酸酯类农药及3种代谢物残留量

研究了用ＷａｔｅｒｓＣａｒｂａｍａｔｅ分析系统柱后衍生化荧光检测器测定谷物中氨基甲酸酯类农药残留量的方法。用ＷａｔｅｒｓＣａｒｂａｍａｔｅＡｎａｌｙｓｉｓＣｏｌｕｍｎ对９种农药和３种代谢产物进行分离，碱液水解，ＯＰＡ柱后衍生，有很好的选择性、重现性和灵敏度，最低检出限为５μｇ／ｋｇ。

Simultaneous Determinations of Carbamate Pesticides in Cereal by High Performance Liquid Chromatography with Post Column Fluorescence Derivatization

A liquid chromatographic method for the simultaneous determination of carbamate pesticides in cereal by Waters Carbamate Analysis System with post-column fluorescence derivatization is described. The cereal sample homogenate was extracted with acetone and water. The extract was partitioned between 5% sodium chloride solution and dichloromethane. The dichloromethane layer was concentrated to dryness. The residue was dissolved in n-hexane and extracted with acetonitrile (saturated with n-hexane). The acetonitrile layer was decreased with n-hexane (saturated with acetonitrile), then the acetonitrile layer was concentrated to dryness. The residue was dissolved in methanol. It's the test solution for HPLC. Nine carbamate pesticides and their three metabolites were separated by Waters Carbamate Column with gradient elution. Two steps underwent in the post-column system: hydrolysis by NaOH solution and the reaction of the product with o-phthalaldehyde and 2-mercaptoethanol. The resulting fluorescence derivative was detected at 445 nm (excitation at 339 nm). The selectivity, reproducibility and sensitivity of proposed method are better than those reported with other methods. The detection limits was 5 micrograms/kg of samples.