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 multi-residues in strawberry,including seven fungicides such as chlorothalonil,procymidone,flutriafol,myclobutanil,kresoxim-methyl,difenoconazole and dimethomorph;four insecticides such as chlorpyrifos,cyhalothrin,pyridaben and fenvalerate;two herbicides such as atrazine and acetochlor.Methods After the homogenized strawberry samples with 20 g were extracted with acetonitrile by 50 mL and purified with NH2 solid-phase extraction column,the samples were separated by HP-5 gas chromatography column and detected with GC-ECD.Results A good separation for 13 pesticides was achieved using the established method,with correlation coefficients above 0.996.The detection limit of the method was0.01~0.5 mg/kg.Shown as the addition recovery experiments,the method average recoveries of the 13 pesticides ranged from 70.5%to 114.5%in the range of 0.01 mg/kg~2 mg/kg.The relative standard deviation was2.17%~6.85%.Conclusion The method showed simple,rapid,and sensitive,with good purifying effect and high recovery rate,and was suitable for the detection and security monitoring of pesticide residues in strawberry.Six kinds of pesticides,chlorothalonil,chlorpyrifos,acetochlor,flutriafol,kresoxim methyl,and dimethomorph,were found through the detection in 50 strawberry samples.