采用超高效液相色谱-串联质谱建立了茶叶中草甘膦和草铵膦残留同时快速测定的方法。茶样经超纯水、二氯甲烷提取和C18固相萃取柱净化后，在硼酸盐缓冲液中与9-芴甲氧羰酰氯（ FMOC-Cl）进行衍生反应，衍生后产物在 C18色谱柱上进行超高效液相色谱分离；质谱检测采用电喷雾正离子化模式和多反应监测模式。结果表明，在0.003125~0.1 mg／L范围内，草甘膦和草铵膦均有良好的线性关系（ r>0.990），检出限（ LOD）均为0.03 mg／kg；在添加浓度为0.375、1.5和4.5 mg／kg时，草甘膦的平均回收率为87.37％~99.11％，相对标准偏差（ RSD）（ n=6）为0.68％~1.35％；草铵膦的平均回收率为81.44％~86.17％，RSD（ n=6）为1.01％~2.33％。该方法样品前处理简单，分析时间短，回收率和精密度等均符合农药多残留检测技术的要求，适用于茶叶中草甘膦和草铵膦残留的同时检测。%A method was developed for the determination of glyphosate( GLY)and glufosinate-ammonium( GLUF)in tea using ultra performance liquid chromatography-tandem mass spec-trometry( UPLC-MS/MS). The sample was extracted with ultrapure water and dichloromethane for 30 min under ultrasonication,followed by a simple cleanup with a C 18 solid phase extraction ( SPE)cartridge,and then GLY and GLUF were derivatized using 9-fluorenylmethoxycarbonyl (FMOC-Cl)in borate buffer for 2 h. The derivatives of GLY and GLUF were separated on a Waters C18 column(50 mm×2. 1 mm,1. 7 μm)in a gradient elution mode,and finally detected with positive electrospray ionization-mass spectrometry ( ESI-MS/MS ) in multiple reaction monitoring( MRM ) mode. The quantification analysis was performed by external standard method. The method showed a good linearity( r>0. 990)in the range of 0. 003 125-0. 1 mg/L. The limits of detection( LODs)of GLY and GLUF were 0. 03 mg/kg. At the spiked levels of 0. 375,1. 5 and 4. 5 mg/kg,the recoveries of GLY and GLUF were 87. 37%-99. 11% and 81. 44%-86. 17% respectively,and the relative standard deviations( RSDs)( n=6)of GLY and GLUF were 0. 68%-1. 35% and 1. 01%-2. 33%,respectively. This method is simple,rapid and charac-terized with acceptable sensitivity and accuracy to meet the requirements for the analysis of GLY and GLUF simultaneously in tea.
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