通过式固相萃取-超高效液相色谱串联质谱法测定花椒中草甘膦及代谢物残留

Determination of Glyphosate and Metabolite Residues in Chinese Prickly Ash by Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry with Pass-through Solid Phase Extraction

[目的]建立一种通过式固相萃取-超高效液相色谱串联质谱法检测花椒中草甘膦及其代谢物的方法。[方法]样品使用水提取,二氯甲烷液液萃取,采用亲水亲脂固相萃取柱进行通过式净化,净化液在碱性条件下用氯甲酸-9-芴基甲酯丙酮溶液进行衍生后,使用ACQUITY UPLC HSS T3色谱柱进行分离,以0.1%的甲酸水和乙腈为流动相按比例进行梯度洗脱,采用正离子模式、质谱多重反应监测模式(MRM),利用同位素稀释法绘制标准曲线。[结果]草甘膦及其代谢物在5~500μg/L呈现良好的线性关系(R^(2)>0.99),方法检出限为5.0μg/kg,方法的回收率为87.4%~97.1%,精密度相对标准偏差(RSD)<10%。[结论]该方法操作流程简便、结果准确可靠,可应用于花椒中草甘膦及其代谢物残留的检验检测。

[Objective]To establish a method for the detection of glyphosate and its metabolites in Chinese prickly ash by ultra high performance liquid chromatography tandem-mass spectrometry with pass-through solid phase extraction.[Method]The samples were extracted with water and liquid-liquid extraction with dichloromethane,purified by hydrophilic lipophilic solid phase extraction column,and then precolumn-derived with 9-fluorenyl methylchlor under alkaline condition.Separated with ACQUITY UPLC HSS T3 chromatographic column.0.1%formic acid water and acetonitrile were used as mobile phase for gradient elution in proportion.Positive ion mode,mass spectrometry multiple reaction monitoring mode(MRM)were used,and draw standard curve by isotope dilution method.[Result]Glyphosate and its metabolites showed a good linear relationship between 5 and 500μg/L(R^(2)>0.99).The detection limit of the method was 5.0μg/kg,the recovery rates of the method were 87.4%-97.1%,and the relative standard deviation(RSD)of the precision was less than 10%.[Conclusion]The method is simple in operation,accurate and reliable in results,and can be applied to the detection method of glyphosate and its metabolite residues in Chinese prickly ash.