直接进样-高效液相色谱-串联质谱法快速检测饮用水中草铵膦、草甘膦及其代谢物氨甲基膦酸

Rapid determination of glufosinate ammonium, glyphosate and aminomethyl phosphonic acid in drinking water by direct injection-liquid chromatography-tandem mass spectrometry

建立了高效液相色谱串联三重四极杆质谱(HPLC-MS/MS)定量检测饮用水中草铵膦、草甘膦及其代谢产物氨甲基膦酸的方法。水样直接经亲水PTFE膜过滤,以50 mmol/L甲酸铵(pH 3.0)为流动相,Acclaim Trinity Q1色谱柱分离,电喷雾离子化(ESI-)、选择反应监测(SRM)模式检测,外标法定量,总运行时间仅为5 min。草甘膦、氨甲基膦酸和草铵膦在10.0~1000μg/L浓度范围内存在较好的线性关系,相关系数大于0.999,其定量限分别为5.0,5.0和10.0μg/L;目标化合物日内和日间加标回收率分别为92.7%~102.1%和89.3%~99.9%,日内与日间相对标准偏差(RSD)均小于7.7%。该方法能满足水源水和饮用水中草铵膦、草甘膦及其代谢物氨甲基膦酸的应急检测或日常检测要求。

A method for quantitative analysis of glufosinate ammonium,glyphosate,and its metabolite of aminomethyl phosphonic acid in drinking water was established by utilizing liquid chromatography coupled with triple quadrupole mass spectrometry(LC-MS/MS).The water sample was directly filtered through a O.22μm PTFE membrane.The analytes were separated on an Acclaim Trinity Q1 column with the mobile phase of 50 mmol/L ammonium formate(pH 3),and detected in selected reaction monitoring(SRM)mode via negative electrospray ionization(ESI-).The external standard method was used for quantitation.There were good linearities for glufosinate ammonium,glyphosate,and aminomethyl phosphonic acid in the concentration ranges of 10.0-1000μg/L,respectively,and the correlation coefficients were higher than 0.999.The quantification limits of glufosinate ammonium,glyphosate,and aminomethyl phosphonic acid in drinking water were 5.0,5.0 and 10.0μg/L,respectively.The inter-day and intra-day recoveries of glufosinate ammonium,glyphosate,and aminomethyl phosphonic acid were 92.7%-102.1%and 89.3%-99.9%,respectively,with the inter-day and intra-day relative standard deviations(RSDs)lower than 7.7%.The method can satisfy the requirements of emergency testing or routine testing.