基质固相分散-气相色谱法检测茄子粉中3种有机磷农药残留

Matrix Solid-Phase Dispersion Extraction and Gas Chromatography Determination of Three Organophosphorus Pesticides in Eggplant Powder

建立了基质固相分散技术结合气相色谱测定茄子粉中甲胺磷、乐果、毒死蜱残留的方法.茄子粉经与中性氧化铝研磨,乙酸乙酯淋洗,浓缩定容,气相色谱分析,外标法定量.结果表明,3种有机磷在0.02～1.0 mg/L质量范围内有良好的线性关系(R2>0.99);在0.1、0.4、0.8 mg/kg 3个加标水平上的回收率为84.2%～98.5%;相对标准偏差为1.6%～6.8%,甲胺磷、乐果、毒死蜱的检出限分别为0.01、0.01、0.005 mg/mL.该方法操作简便快速,样品和试剂用量少,可以满足茄子粉中甲胺磷、乐果、毒死蜱残留的检测要求.

A method for the determination of three organophosphorus pesticides including methamidophos, dimethoate and chlorpyrifos in eggplant powder is developed by GC with matrix solid phase dispersion. The sample is graphitized with neutral alumina, eluted with ethyl acetate, and quantified by external standard method. The results show that there is a good linear relationship （R2 〉 0. 99） in the concentration range of 0. 02 - 1.0 mg/L;the recoveries are 84. 2% -98.5% in 3 standard levels（0. 1,0. 4,0. 8 mg/kg） ;and the detection limits are 0. 01,0. 01, 0. 005 mg/kg for metharnidophos, dimethoate and chlorpyrifos, respectively. The method is simple and rapid, which can satisfy the testing requirements of methamidophos, dimethoate and chlorpyrifos in eggplant powder.