GC-MS法同时测定食品风险监测样品中的农残

Simultaneous determination of pesticide residues in food safety risk monitoring in 2011 by gas chromatography-mass spectrometry

目的:建立同时检测食品安全风险监测样品中的农残的GC—MS法,农残包括有机磷类9种、有机氯类1种、氨基甲酸酯类3种、拟除虫菊酯类4种。方法:样品中所含农药残留用乙腈一并提取,浓缩至近干,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,浓缩后用GC-MS法测定。结果:有机磷农药最低检出浓度为0.01 mg/L～0.05 mg/L,有机氯为0.005 mg/L,氨基甲酸酯类为0.03 mg/L,拟除虫菊酯为0.005 mg/L～0.01 mg/L,标准曲线r值均≥0.995,加标回收率为67.6%～108.3%,RSD为2.5%～8.3%。结论:该法能将2011年食品安全风险监测所有的农残类项目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 pesticide residues in food safety risk monitoring samples.The pesticides include 9 kinds of organophosphorus,1 kind of organochlorine pesticides,3 kinds of carbamates and 4 kinds of pyrethroids.Methods： Samples were extracted using acetonitrile and then rotary evaporated to nearly dryness,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 analyzed by GC.MS.Results： The results showed that the detection limit was 0.01 mg/L^0.05 mg/L for organophosphorus,0.005 mg/L for organochlorines,0.03 mg/L for carbomates and 0.005 mg/L^0.01 mg/L for pyrethroids.The linear coefficient was ≥0.995 with recoveries of 67.6%~108.3%,and the RSD was 2.5%~8.3%.Conclusion： This method is able to determine all pesticide residues in food safety risk monitoring samples in 2011 at the same chromatographic and mass spectrometric conditions,and the method is sensitive and reproducible with high accuracy and precision,which can be used in the actual testing analysis.