This paper established the method for determination of 12 organophosphorus pesticides by gas ghromatography ( GC ) combinated with accelerated solvent extration ( ASE) and solid phase Extration ( SPE). The condition parameters of GC were recommended. The technology of ASE was applied with optimized parameters to reduce the loss of target compounds to obtain better recoveries of 88%-108% . Three purification experiments with different SPE columns and solvents were discussed, and the results showed that the experiment eluting silicone SPE columns with mixed elution solvent ( hexane: aceone: dichloromethane = 1: 1:1) obtained a high purification efficiency with recoveries of 91% -121% . Detection limits of the average organophosphorus pesticides were in the range of 0. 000 1-0. 000 2 mg/kg,and the spiked recoveries of 12 compents in the quartz sand and polluted soil samples were between 62% and 112% with precision of relative standstard deviations ( RSD, n = 7 ) of 0. 7% -8. 6% . This method had the advantage of rapid sample analysis , simple operation, highsensitivity, low detection limits and little toxic and hazardous reagents, also , the detection precision and accuracy could meet with the requirements of laboratory quality control.%建立了加速溶剂萃取-固相萃取小柱净化-气相色谱法测定土壤中12种有机磷农药的方法.推荐了12种有机磷农药快速分离的色谱条件.采用加速溶剂萃取技术实现了对土壤中有机磷农药残留的提取,选取最佳条件参数,减少了组分的损失,提取回收率达88％ ～ 108％.选择不同填料的SPE小柱和洗脱溶剂形成3种方案法进行净化实验,结果表明,方案2采用混合溶剂(正己烷、丙酮、二氯甲烷体积比为1∶1∶1)洗脱上样后的硅胶SPE小柱的净化效果好,回收率为91％ ～ 121％.方法检出限为0.000 1～0.000 2 mg/kg,石英砂基体和实际污染土壤样品加标回收率为62％ ～112％,相对标准偏差为0.7％～8.6％.该方法操作简便,快捷,灵敏度高,检出限低,试剂用量少,准确度和精密度符合质量控制要求.
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