分散固相萃取-气相色谱法测定大米中六六六 和滴滴涕残留量

Simultaneous determination of hexachlorocyclohexane and dichlorodiphenyltrichloroethane residues in rice by dispersive solid phase extraction and gas chromatography

中文关键词:  六六六  滴滴涕  分散固相萃取  气相色谱法  大米

英文关键词:hexachlorocyclohexane  dichlorodiphenyltrichloroethane  dispersive solid phase extraction  gas chromatography  rice

中文摘要:

      目的 建立气相色谱-电子捕获检测器法(GC-ECD)测定大米中六六六和滴滴涕(α-六六六、β-六六六、γ-六六六、δ-六六六、o,p’-滴滴滴、o,p’-滴滴伊、o,p’-滴滴涕、p,p’-滴滴滴、p,p’-滴滴伊、p,p’-滴滴涕)残留量的方法。方法 大米样品经乙腈超声提取后, 应用PSA进行分散固相萃取净化, 高速离心后氮吹浓缩定容, 最后使用气相色谱电子捕获检测器测定。结果 六六六和滴滴涕在0.002~0.1 mg/L浓度范围内呈现良好线性关系, R2大于0.99; 在0.002、0.005、0.01 mg/kg三个添加浓度上回收率范围为84.10%~111.43%, 相对标准偏差小于9.23%, 检出限在0.0001~0.0007 mg/kg之间。结论 该方法前处理操作快速简单, 重复性好且灵敏度高, 满足国内外对大米中六六六和滴滴涕快速、准确检测的要求, 可应用于大量样品的定性定量分析。

英文摘要:

      Objective To develop a method for the simultaneous determination of hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) (α-HCH, β-HCH, γ-HCH, δ-HCH, o,p’-DDD, o,p’-DDE, o,p’-DDT, p,p’-DDD, p,p’-DDE, p,p’-DDT) residues in rice by gas chromatography with ECD detector using dispersive solid phase extraction. Methods Rice samples were extracted with acetonitrile assisted by ul-tra-sonic, and the extracts were purified by dispersive solid phase extraction using PSA as the purification sorbent. After high speed centrifugation and concentrated by nitrogen flushing, samples were detected by GC-ECD. Results The method showed a good linearity in the range of 0.002~0.1 mg/L for HCH and DDT with R2>0.99. The recoveries were in the range of 84.10%~111.43% at three spiked levels of 0.002, 0.005, 0.01 mg/kg for HCH and DDT, and the relative standard deviations (RSDs) were less than 9.23%. The limits of detections were in the range of 0.0001~0.0007 mg/kg. Conclusion The method is suitable for quantitative and qualitative analysis of HCH and DDT in a sufficient number of rice samples with sensitivity and repeatability, and which could meet the fast and accurate detection requirements of HCH and DDT residues testing at home and abroad.