固相萃取-气相色谱法测定小麦粉中六六六和滴滴涕残留量

Determination of BHC and DDT Pesticide Residues in Wheat Flour by Solid-phase Extraction and Capillary Gas Chromatography

[目的]建立小麦粉中六六六和滴滴涕农药残留量的固相萃取-气相色谱分析方法。[方法]以乙腈为提取剂,超声提取,采用Carbon NH2固相萃取柱净化,用乙腈-甲苯（3＋1,V/V）作为洗脱液,经HP-1毛细管色谱柱分离后使用电子捕获检测器（ECD）测定。[结果]六六六和滴滴涕农药的质量浓度为0.005-0.400μg/m L时线性良好,相关系数为0.998 6-0.999 5。在0.05、0.10、0.20 mg/kg3个添加水平下,六六六和滴滴涕的加标回收率在80.21%-113.41%,相对标准偏差在1.30%-4.33%（n=6）,检出限为0.10-1.51μg/kg。[结论]该方法具有样品前处理操作简单、灵敏度高、试剂用量少、重现性好等优点,适用于小麦粉中六六六、滴滴涕的定性定量分析。

[ Objective ] A capillary gas chromatography method was developed for determination of BHC and DDT pesticide residues in wheat flour. [ Method] The pesticide residues in the samples were extracted by ultrasonic assisting oscillation and using acetonitrile as extraction agent. The extract solution was purified by Carbon NH2 Cartridges and eluted with the mixture of acetonitrile-toluene （3 ＋ 1, V/V） . Finally, the target components were determined using electron capture detector （ECD） after separated from each other through HP-1 capillary column. [ Result] The calibration curves were linear in the range of O. 005-0.400 μg/mL with the correlations coefficients of 0.998 6-0.999 5. The recoveries for BHC and DDT in three added levels were in the range of 80.21% -113.41%. The relative standard deviations were 1.30%-4.33% （n = 6）. The limits of detection （LODs） were in the range of 0. 10-1.51 μg/kg. [ Conclusion] The method is simple, sensitive, less reagent and reproducible, and it is suitable for quantitative and qualitative analysis of BHC and DDT in wheat flour.