蔬菜中22种农药及其代谢物残留的分散固相萃取-分散液液微萃取-气相色谱串联质谱测定法

Determination of 22 pesticide and metabolites residues in vegetables by dispersive solid-phase extraction and dispersive liquid-liquid microextraction combined with gas chromatographytandem mass spectrometry

目的建立分散固相萃取结合分散液液微萃取-气相色谱串联质谱法测定蔬菜中22种农药残留及其代谢物残留的测定方法。方法样品经过乙腈提取后,经过QuE Verde净化后,以乙腈为分散剂,四氯乙烯为萃取剂进行提取。采用气相色谱串联质谱(GC-MS-MS)的多反应检测模式(MRM)对多种农药及其代谢产物残留进行定性定量测定。结果22种农药的标准曲线在5.0~400μg/L范围内线性良好,相关系数均>0.9990,回收率为72.4%~93.9%,RSD为4.8%~12.6%,检出限和定量限分别为0.04~0.12μg/kg和0.13~0.36μg/kg。结论该方法操作简单便捷、富集倍数高、灵敏度高、重现性好,可用于实际蔬菜样品中农残的监测。

Objective To establish a method for the determination of 22 pesticide residues and metabolites residues in vegetables by dispersive liquid-liquid microextraction-gas chromatography-tandem mass spectrometry.Methods Samples were extracted with acetonitrile and purified by QuE Verde solid phase extractant,and then acetonitrile and tetrachloroethylene were used as dispersant and extractant respectively.The 22 pesticides and metabolites residues were qualitatively and quantitatively analyzed by tandem mass spectrometry in multi reaction monitoring mode(MRM)and separated by DB-5 MS column(30 m×0.25 mm,0.25μm).Results The calibration curves of 22 pesticides had a good linearity in the range of 5.0-400μg/L,all correlation coefficients were greater than 0.9990.In the spiked recovery test,the average recoveries were 72.4%-93.9%,while the relative standard deviations(RSD)were 4.8%-12.6%.The limits of detection and limits of quantitation were 0.04-0.12μg/kg and 0.13-0.36μg/kg respectively.Conclusion This method is simple and convenient to operate,has high enrichment multiples,high sensitivity,and good reproducibility,and can be used for the quality supervision of actual commercially available vegetables products.