QuEChERS-气相色谱-三重四极杆质谱法同时测定枸杞中46种农药残留

建立了QuEChERS结合气相色谱-三重四极杆质谱法(GC-MS/MS)同时检测枸杞中46种农药残留的方法。样品经乙腈提取后,使用无水硫酸镁、N-丙基乙二胺(N-propyl ethylenediamine,PSA)进行净化,以HP-5MS色谱柱分离待测物,GC-MS/MS采用多反应监测(multiple reaction monitoring mode,MRM)模式检测,基质匹配外标法定量。结果表明,46种农药在0.01~0.20 μg/mL范围内线性关系良好,相关系数r>0.99。方法检出限(S/N=3)在0.02~3.90 μg/kg的范围内,方法定量限(S/N=10)在0.05~12.99 μg/kg的范围内;在10、50、100 μg/kg的加标水平下,46种化合物平均加标回收率达71.5%~99.8%,相对标准偏差为0.7%~8.9%。10批次枸杞样品中4批次检出农药残留,含量范围为19.4~262 μg/kg。该方法快速、灵敏、准确,适用于枸杞中多种农药残留的检测。

Simultaneous Determination of 46 Pesticide Residues in Lycium barbarum by QuEChERS Method Combined with Gas Chromatography-Triple Quadrupole Mass Spectrometry

A method for simultaneous determination of 46 pesticide residues in Lycium barbarum by QuEChERS method combined with gas chromatography-triple quadrupole mass spectrometry(GC-MS/MS)was established.The samples were extracted with acetonitrile,then purified by anhydrous magnesium sulfate and N-propyl ethylenediamine(PSA).The target pesticides were separated by HP-5 MS column,tested by GC-MS/MS with multiple reaction monitoring mode(MRM),and quantified by external standard method considering matrix effects.The correlation coefficients were higher than 0.99,which indicated that the linear dependence of the 46 pesticide residues were good in the range of 0.01~0.20μg/mL.The limits of detection(S/N=3)were in the range of 0.02~3.90μg/kg,and the limits of quantitation(S/N=10)were in the range of 0.05~12.99μg/kg.The average recoveries were 71.5%~99.8%with the relative standard deviations of 0.7%~8.9%at the spiked levels of 10,50 and 100μg/kg.Pesticide residues were detected in 4 of the 10 batches of Lycium barbarum samples,the content ranged from 19.4 to 262μg/kg.The method is rapid,sensitive and accurate,which is suitable for the detection of multi-pesticide residues in Lycium barbarum.