固相萃取-气相色谱法检测蔬菜中8种菊酯类 农药残留

目的建立一种固相萃取-毛细管柱气相色谱方法,可以同时检测蔬菜中8种菊酯类农药残留。方法蔬菜样品匀浆后,经正己烷/丙酮(V:V=50:50)提取,Florisil固相萃取柱净化,HP-5毛细管气相色谱柱进行分离,GC-ECD进行定性及定量分析。结果 8种菊酯类农药残留的色谱图分离效果良好,线性相关系数均大于0.995,方法检出限在0.0025~0.02 mg/kg之间。8种菊酯类农药的添加水平为0.025~2 mg/kg,回收试验表明该方法平均回收率在73.6%~97.0%之间,相对标准偏差小于5%。结论该方法样品处理简单、仪器配置要求较低、净化效果好、易于推广使用,适合蔬菜中多种菊酯类农药残留的检测和安全监控。

Simultaneous determination of residues of 8 pyrethroid pesticides in vegetables with solid phase extraction-gas chromatography

Objective To establish a solid phase extraction-capillary gas chromatography method for the determination of 8 pesticide residues in vegetables. Methods After the homogenized vegetable samples with hexane/acetone (V:V=50:50) and purified with Florisil solid-phase extraction column, the samples were separated by HP-5 gas chromatography column and detected with gas chromatography-electron capture detector (GC-ECD). Results A good separation for 8 pyrethroid pesticides was achieved using the established method with correlation coefficients above 0.995. The detection limit was 0.0025~0.02 mg/kg, the average recoveries of the 8 pyrethroid pesticides were from 73.6% to 97.0% in the range of 0.025~2 mg/kg. The relative standard deviation was less than 5%. Conclusion This method is simple for sample treatment, low requirements of the instrument configuration, with agood purifying effect and ease popularization, and is suitable for the detection and security monitoring of pesticide residues in vegetables.