缓冲QuEChERS气相色谱电子捕获检测法测定蔬菜中52种含卤素农药残留

GC-ECD determination of 52 halogen-containing pesticide residues in vegetables using buffered QuEChERS

目的：建立快速测定蔬菜中常见的52种含卤素农药残留的气相色谱电子捕获检测方法。方法：10 g样品用10 ml 0.1%乙酸的乙腈快速提取、无水醋酸钠和无水硫酸镁盐析后,经Florisil柱固相萃取净化,气相色谱电子捕获检测器检测,基体标准定量。结果：52种含卤素农药的加标回收率在60%～124%,相对标准偏差在1%～18%之间,检出限为0.0005～0.005 mg/kg。结论：本法灵敏、准确,适合于蔬菜中含卤素农药多残留分析。

Objective：To develop a simple,fast,and inexpensive GC-ECD method for the determination of 52 halogen-containing pesticide residues in vegetables.Methods：The procedure included the extraction of 10 g sample with 10 ml acetonitrile containing 1% acetic acid,followed by liquid-liquid partitioning formed by adding 4 g anhydrous magnesium sulfate plus 1 g sodium acetate.After the extract was processed by florisil solid-phase extraction,the eluate was detected by GC-ECD,and quantified by matrix-match standard solution.Results：Recoveries between 60% and 124% and RSD ranged from 1% to 18% have been achieved.The limits of detection for all 52 pesticides containing halogen were within 0.0005 and 0.005 mg/kg.Conclusion：The method is found to be sensitive and accurate for determination of the 52 halogen-containing pesticide residues in vegetables.