GC-MS法同时测定食品中35种常见的农残

Simultaneous Determination of 35 Kinds of Pesticide Residues in Food by Gas Chromatography-mass Spectrometry

目的建立用GC-MS同时检测食品中35种常见农药的方法。方法样品中所含农药残留用乙腈一并提取,浓缩近干,经丙酮和二氯甲烷混合液溶解,无水Na2SO4脱水,过Carb/NH2柱、硅镁柱净化,浓缩待测定。结果实验结果显示最低检出限为0.005~0.05 mg/L,加标回收率为70.6%~113.5%,RSD为1.5%~7.8%,标准曲线r值均≥0.995。结论该方法能够将食品中常见的35种农残在同一色谱及质谱条件下检测,能实现良好的分离,定性定量准确、灵敏、重现性良好,可用于实际样品检测分析。

Objective To establish a gas chromatography-mass spectrometric method for simultaneous determination of 35 kinds of pesticide residues in food samples.Methods Samples were extracted using acetonitrile and then evaporated nearly to dryness with a rotary evaporator.The concentrated extract was dissolved with acetone and methylene chloride mixture and dehydrated with anhydrous Na2SO4 and finally purified with Carb/NH2 column and silicon magnesium column.The purified solution was concentrated before analysis by gas chromatography-mass spectrometry.Results The results showed that the detection limit was 0.005~0.05 mg/L,the recoveries of standard addition were 70.6%~113.5%,and the RSD was 1.5%~7.8%.The linear coefficients were ≥0.995.Conclusions This method is able to determine 35 kinds of pesticide residues in food safety risk monitoring samples in 2011 at the same chromatographic and mass spectrometric conditions.It is sensitive and reproducible,and of high accuracy and precision,which can be used in the actual testing analysis.