气相色谱法测定鱼、虾中拟除虫菊酯类农药残留

Determination of Pyrethroid Pesticide Residues in Fish and Shrimp by Gas Chromatography

本文建立了同时测定鱼、虾中氰戊菊酯、氯氰菊酯及溴氰菊酯的方法。样品经乙腈提取,乙腈饱和正己烷除脂、氟罗里硅土柱净化,正己烷复溶后采用气相色谱仪检测,外标法定量。结果表明,在5~500μg/L范围内,3种农药的质量浓度与其对应的峰面积之间线性关系良好,R2均大于0.999。在5μg/kg、10μg/kg和50μg/kg这3个添加水平下,重复测定6次,3种农药的回收率在70%~100%之间,RSD<15%,符合GB 27404-2008对实验室内变异系数的要求。该方法能够为有效监测鱼、虾中的氰戊菊酯、氯氰菊酯及溴氰菊酯残留提供有效、经济的分析手段。

A method for simultaneous determination of fenvalerate,cypermethrin and deltamethrin in fish and shrimp was established.The samples were extracted by acetonitril which was saturated n-hexane with removing the fat,and purified on a flori silica column.After n-hexane was dissolved,the samples were detected by gas chromatograph and quantified by external standard method.The result showed that there was a good linear relationship between the mass concentrations of the three pesticides and their corresponding peak areas in the range of 5-500μg/L,with R2 greater than 0.999.The recoveries of the three pesticides were in the range of 70%-100%and the RSD was less than 15%at 5μg/kg,10μg/kg and 50μg/kg supplemental levels for six times,which met the requirements of the laboratory coefficient of variation for GB 27404-2008.Therefore,this method is effective and economical for the determination of fenvalerate,cypermethrin and deltamethrin in fish and shrimp.