气相色谱法测定大米中有机磷残留量的方法探究

Determination of Residual Organic Phosphorus in Rice by Gas Chromatography

应用气相色谱技术，建立大米中敌敌畏、乐果、马拉硫磷、对硫磷等4种有机磷农药残留的测定方法，采用QuEChERS技术简化样品前处理过程，通过试验确立了使用丙酮：乙酸乙酯（1：1）作为提取溶剂。测定结果表明4种农药在大米中的分离状况良好，14min内就出峰完毕。4种农药在3个添加水平下的平均回收率为81％-97％，相对标准差在2．1％-9．9％之间，检出限在0．002-0．003mg／kg之间，满足检测要求。

Application of gas chromatography technology, the establishment of rice dichlorvos, dimethoate, malathion, and the method for the determination of parathion four kinds of organic phosphorus pesticide residues by QuEChERS technique simplified sample pretreatment process, the test established using acetone： ethyl acetate （1 ： 1） as the extraction solvent. The results showed that the separation of the 4 Pesticides in rice was good, and the peak of 14 min was over. The average recovery rate of 4 Pesticides in 3 adding levels was 97 %-81%, the relative standard deviation was between 9.9 % and 2.1%, and the detection limit was between 0.002-0.003 mg/kg, which can meet the requirements of detection.