Determination of Pyrethroid Residue in Cabbage by Gas Chromatography Combined with Dispersive Solid-phase Extraction and Dispersive Liquid-Liquid Extraction
Determination of Pyrethroid Residue in Cabbage by Gas Chromatography Combined with Dispersive Solid-phase Extraction and Dispersive Liquid-Liquid Extraction[J]. 2014,33(2):192-196.
Determination of Pyrethroid Residue in Cabbage by Gas Chromatography Combined with Dispersive Solid-phase Extraction and Dispersive Liquid-Liquid Extraction[J]. 2014,33(2):192-196.DOI:
A gas chromatographic method for the determination of pyrethroid pesticide residues(e.g.cyfluthrin,cypermethrin,deltamethrin and fenvalerate) in cabbage was developed using dispersive solid-phase extraction and dispersive liquid-liquid microextraction as sample preparation methods.The samples were extracted with acetonitrile,purified with primary secondary amine as sorbents,and concentrated into 50 μL dimethyl benzene by dispersive liquid-liquid microextraction.The analytes were analyzed by gas chromatography with electron capture detector.Factors affecting the extraction efficiency such as type and volume of extraction solvent,volume of dispersive solvent and salt effect,were investigated.Under the optimized conditions,the enrichment factors(EF)for four pyrethroid pesticides ranged from 100 to 297.The calibration curves were linear in the range of 0.01-0.1 mg/L for cyfluthrin,and 0.01-5 mg/L for the rest of targeted compounds,with correlation coefficients of 0.997 9-0.999 2.The limits of detection for cyfluthrin,cypermethrin,fenvalerate and deltamethrin were 0.03,0.02,0.01,0.01 μg/kg,and the limits of quantitation were 0.10,0.06,0.04,0. 04 μg/kg,respectively.Except of cyfluthrin,the recoveries of other three compounds at spiked levels of 0.02- 0.5 μg/g ranged from 81.9% to 93.5%,with RSDs of 9.5%-20.7%.With the advantage of quickness,low toxicity and high enrichment factors,the proposed method is applicable for the analysis of pyrethroid pesticide residues in cabbage samples.