通过式固相萃取/超高效液相色谱-串联质谱法测定蔬菜中18种农药残留

建立了超高效液相色谱-串联质谱(UPLC-MS;MS)快速测定蔬菜中18种农药残留的方法.样品经乙腈提取后,经Oasis PRiME HLB固相萃取柱净化,采用ACQUITY UPLC HSS T3 C18(50 mm×2.1 mm,1.8μm)色谱柱进行分离,以0.1%甲酸水溶液和乙腈作为流动相进行梯度洗脱.采用电喷雾电离源、正离子模式下以多反应监测(MRM)进行定性和定量分析.结果表明,18种农药在0.5—50μg·L^-1范围内线性关系良好(r2>0.995),方法最低检出限为0.4—1.5μg·kg^-1,最低定量限为1.4—5.0μg·kg^-1.在韭菜、芹菜、番茄、白菜基质中,5、10、50μg·kg^-1添加水平下的加标回收率为60.2%—126.9%,相对标准偏差(RSD)为0.4%—21.6%(n=3).

Determination of 18 pesticide residues in vegetables by ultra-performance liquid chromatography-tandem mass spectrometry with pass-through solid phase extraction

An ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS;MS)method was established for the rapid determination of 18 pesticide residues in vegetables.Samples were extracted with acetonitrile and cleaned up by the Oasis PRiME HLB column.The separation was performed on an ACQUITY UPLC HSS T3 C18(50 mm×2.1 mm,1.8μm)column with 0.1%formic acid aqueous solution and acetonitrile as mobile phase by gradient elution.The mass spectrometer was operated in multiple monitoring(MRM)mode with positive mode.The 18 pesticides showed great linear relationships in the range of 0.5-50μg·L^-1with correlation coefficients(r2)greater than 0.995.The limits of detection(LODs)and limits of quantitation(LOQs)were in the ranges of 0.4-1.5μg·kg^-1and 1.4-5.0μg·kg^-1,respectively.The average recoveries of targets varied from 60.2%to 126.9%,in leek,celery,tomato,cabbage,and the relative standard deviations were between 0.4%and 21.6%at the spiked levels of 5,10 and 50μg·kg^-1.