液相色谱-质谱联用法同时测定食品中37种农药残留

[目的]建立一种食品中农药残留的液相色谱质谱测定方法。[方法]本法采用乙腈匀浆提取,盐析离心后,经固相萃取柱净化,用乙腈＋甲苯（3＋1）洗脱农药,根据不同检测要求用液相色谱-质谱联用法检测农药多残留组份。[结果]所有37种农药均在40 min内流出,农药标准的线性范围在0.01-1.0μg/ml,相关系数r均在0.99以上,低、高浓度加标回收率均在78%-96%之间,相对标准偏差均小于10%,方法最低检出限在0.001-0.04 mg/kg（S/N=3）。[结论]方法选择性强,适合于食品中有机磷、有机氯、拟除虫菊酯、氨基甲酸酯、除草剂农药残留的测定,且准确度好,精密度高,可快速一次检测37种农药,达到残留量检测中所要求的检测浓度水平。

Determination of 37 Kinds of Pesticide Residues in Foods with Liquid Chromatography Mass Spectrometry

[Objective] To establish the method of liquid chromatography mass spectrometry（LC-MS） for the determination of pesticide residues in foods.[Methods]The pesticides were extracted with acetonitrile.The extract was salted out and centrifuged,and then it was purified by solid phase extraction column and was eluted with acetonitrile and toluene（3＋1）.Afterwards,liquid chromatography mass spectrometry（LC-MS） was used to determine pesticide residues ingredients according to the different requirements.[Results]All the 37 kinds of pesticide residues were drained out within 40minutes;the standard linear range was between 0.01-1.0 μg/ml;correlation coefficient r was above 0.99;the labeled recovery rates were between 78%-96%;the relative standard deviations（RSD） was below 10%;the limit of determination（LOD） was 0.001-0.04 mg/kg（S/N=3）.[Conclusion]This method is suitable for determining pesticide residues in foods with satisfactory sensitivity,accuracy and precision;it can rapidly detect 37 kinds of pesticide and the concentration level reaches the requirement for detection.