固相萃取-气相色谱法同时检测草莓中13种 农药残留

目的 建立一种固相萃取-毛细管柱气相色谱方法,可以同时检测草莓中13种农药残留量。方法 草莓样品匀浆后,经乙腈提取,NH₂固相萃取柱净化,采用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 13 种农药残留的色谱图分离效果良好,线性相关系数均大于0.996,方法检出限在0.01 mg.kg_-1~0.5 mg.kg_-1之间。添加回收试验表明,该方法平均回收率在70.5~114.5 % 之间,相对标准偏差在2.17~6.85 %之间。结论 该方法简单、快速、灵敏、净化效果好、回收率高,适合草莓中多种农药残留的检测和安全监控。通过对50份草莓样品进行检测,检出百菌清、乙草胺、毒死蜱、粉唑醇、醚菌酯、烯酰吗啉6种农药。

Simultaneous determination for the residue of thirteen pesticides in strawberry with solid phase extraction and gas chromatography

Objective To established a solid phase extraction-capillary gas chromatography method for the determination of 13 pesticides multiresidues in strawberry. Methods After the strawberry samples were homogenized and extracted with acetonitrile, purified with NH₂ solid-phase extraction column. The sample separated by gas chromatography with Hp-5 column and detected with GC-ECD. Results Good separation for 13 pesticides was achieved using the established method,with correlation coefficients above 0.996. The detection limit of the method was 0.01~0.5 mg/kg. Showed as the addition recovery experiments,the method average recoveries of the 13 pesticides ranged from 70.5% to 114.5%.The relative standard deviation was 2.17~6.85%. Conclusion The method is simple, rapid, sensitive, good purifying effect, high recovery rate, and can suit for the detection and security monitoring of pesticide residues in strawberry. By testing for 50 strawberry samples,detection of chlorothalonil,chlorpyrifos,acetochlor,flutriafol,kresoxim-methyl and dimethomorph.