QuEChERS/超高效液相色谱-四极杆-飞行时间质谱法同时测定小麦粉中17种农药残留

建立了超高效液相色谱-四极杆-飞行时间质谱(UPLC-Q-TOF/MS)同时测定小麦粉中17种农药残留的检测方法。样品采用QuEChERS方法进行前处理,以0.1%(体积分数)乙酸乙腈溶液提取,PSA和C18吸附剂净化,电喷雾正离子模式检测,外标法定量,同时建立了包含一级精确质量和二级碎片离子信息的筛查确证谱库。在各自的线性范围内,17种化合物的线性关系良好,相关系数均大于0.995。方法的定量下限为5.0~10.0μg/kg,3个加标水平下的回收率为70.3%~114.9%,相对标准偏差(RSD,n=6)为0.4%~11.7%。该方法操作简便、稳定性好,具有较强的实际应用价值。

Simultaneous Determination of 17 Pesticide Residues in Flour by QuEChERS/Ultra Performance Liquid Chromatography Coupled with Quadrupole-Time of Flight Mass Spectrometry

An analytical method was established for the simultaneous determination of 17 pesticide residues in flour by ultra performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry (UPLC-Q-TOF/MS).The QuEChERS method was validated for the extraction.In this method,the samples were extracted with 0.1％ (by volume)acetic acid-acetonitrile solution,and cleaned-up by PSA and C18 adsorbents,then determined by UPLC-Q-TOF/MS with electrospray ionization in positive mode.The quantification analysis was performed by the external standard calibration.A database including accurate mass and fragment ions information was established.The correlation coefficients(r) were more than 0.995 in the linear range of the 17 pesticides.The limits of quantitation(LOQs) of the method were in the range of 5.0-10.0 μg/kg.The recoveries at three spiked levels were between 70.3％ and 114.9％ with relative standard deviations (RSDs,n =6) of 0.4％-11.7％.With the advantages of simplicity and good stability,the method is available for practical application.