UPLC-MS/MS检测转基因大豆及其副产物中的草甘膦及代谢物

Determination of Glyphosate and Its Metabolites in Transgenic Soybean and By-products by UPLC-MS/MS

建立超高效液相色谱-串联质谱法(ultra high performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)测定转基因大豆及其副产物中草甘膦(glyphosate,GLY)及其主要代谢物氨甲基膦酸(aminomethylphosphonic acid,AMPA)的分析方法。样品经0.1%盐酸溶液提取,二氯甲烷脱脂,RM固相萃取柱净化后,与四硼酸钠溶液和芴甲氧羰酰氯溶液进行衍生化反应,经液相色谱柱分离后,在多反应监测模式(multiple reaction monitoring,MRM)下进行草甘膦和氨甲基膦酸的测定,同位素内标法定量。结果表明,草甘膦和氨甲基膦酸在1.0~100.0 ng/mL范围内线性关系良好,相关系数大于0.996,定量限为0.10 mg/kg和0.15 mg/kg,检出限为0.05 mg/kg。在0.05,0.20和0.50 mg/kg 3个加标水平下,平均回收率为90.7%~109.3%,相对标准偏差(relative standard deviations,SRSD)为2.44%~7.56%(n=6)。该方法前处理过程简便、灵敏度高、稳定性好,适用于转基因大豆及其副产物中草甘膦和氨甲基膦酸的日常检测。

Aim to establish a method for the determination of glyphosate and its main metabolite aminomethyl phosphonic acid in transgenic soybean and by-products by ultra high performance liquid chromatography-tandem mass spectrometry.The samples were extracted by 0.1%of hydrochloric acid solution,degreased by dichloromethane,purified by RM solid phase extraction column,and then derivatized with sodium tetraborate solution and 9-fluorenylmethyl chloroformate,separated by liquid chromatography column,the determination of glyphosate and aminomethylphosphonic acid were performed in multiple reaction monitoring mode,and quantified by isotope internal standard method.Glyphosate and aminomethyl phosphonic acid showed a good linearity in the range of 1.0 ng/mL to 100.0 ng/mL,with the correlation coefficients greater than 0.996.The limits of quantification were 0.10 mg/kg and 0.15 mg/kg,and the limits of detection were 0.05 mg/kg.At three spiked levels of 0.05,0.20 and 0.50 mg/kg,and the average recovery rates were between 90.7%and 109.3%.Meanwhile,the relative standard deviations were 2.44%to 7.56%(n=6).The proposed method provided simple pretreatment,high sensitivity and reasonable stability which was suitable for the daily detection of glyphosate and aminomethyl phosphonic acid in transgenic soybean and by-products.