高效液相色谱-四极杆/离子阱质谱确证测定面粉及面制品中氨基脲

摘要

采用高效液相色谱-四极杆/离子阱质谱(HPLC-QTRAP-MS)建立了面粉及面制品中氨基脲的确证及测定方法.样品采用盐酸(HCu提取,在超声辅助下与衍生剂邻硝基苯甲醛反应.衍生产物在中性条件下经PLS固相萃取柱净化、乙酸乙酯洗脱,经Shim-Pack XR-ODSⅢC18柱(2.0 mm×50 mm,1.6 μm)分离,0.1％(体积比)甲酸-水溶液和甲醇溶液为流动相梯度洗脱;采用多反应监测(MRM)-信息依赖性采集(IDA)-增强子离子扫描(EPI)模式检测,EPI谱库确认,内标法定量.结果表明:氨基脲在0.5～40 μg/L范围内线性关系良好(r=0.996);检出限(LOD,S/N=3)为0.10 μg/kg,定量下限(LOQ,S/N=10)为0.25μg/kg;4个加标水平(0.25,0.5,2.0,10.0 μg/kg)下的回收率为89.1％～112.8％;相对标准偏差(RSD)为1.4％～8.6％.该方法分析速度快,灵敏度高,回收率好,可用于面粉及面制品中氨基脲的快速检测.%An analytical method was developed for the identification and detection of semicarbazide (SEM) residues in flour and flour products by high performance liquid chromatography coupled to quadrupole/linear ion trap mass spectrometry (HPLC-QTRAP/MS).Samples were reacted with onitrobenzaldehyde in HCl with assistant of ultrasonic to produce stable derivative,and then the derivative was cleaned up with PLS SPE cartridge,eluted with ethyl acetate.The separation of analytes was carried out on a Shim-pack XR-ODS Ⅲ C1s column(2.0 mm ×S0 mm,1.6 μm) using mobile phases of 0.1％ (by volume) formic acid in ultrapure water and methanol solution by gradient elution.A multiple reaction monitoring (MRM) scan mode and an enhanced product ion (EPI) scan mode as dependent in an information-dependent acquisition (IDA) experiment were used in mass spectrometry acquisition.Lab-built EPI library and the internal standards were adopted for the identification and quantification.The results indicated that the calibration curve of SEM showed a good linearity (r =0.996) whithin the range of 0.5-40 μg/L.The limit of detection (LOD,S/N =3) for SEM was 0.10 μg/kg,and the limit of quantitation(LOQ,S/N =10) was 0.25 μg/kg.The average recoveries of SEM at four spiked levels of 0.25,0.5,2.0,10.0 μg/kg were in the range of 89.1％-112.8％ with relative standard deviations(RSDs) of 1.4％-8.6％.With high sensitivity and good recovery,the proposed method was effectively used to identify and detect the residues of semicarbazide in flour and flour products.