固相萃取-GC-MS/MS法测定海水中莠去津及其代谢物残留研究

Determination of atrazine and its metabolites in seawater by solid phase extraction and gas chromatography tandem mass spectrometry(GC-MS/MS)

采用固相萃取结合气相色谱-串联质谱(GC-MS/MS),建立了海水中痕量莠去津(ATR)及其主要代谢产物脱乙基莠去津(DEA)、脱异丙基莠去津(DIA)和脱乙基脱异丙基莠去津(DDA)的精确定量分析方法.海水样品在萃取前调节pH至3.0,然后经HLB固相萃取柱富集、净化,在GCMS/MS多反应监测模式(MRM)下进行定性、定量分析,并对该方法的线性、检出限、准确度和精密度进行验证分析.结果表明:ATR、DEA、DIA和DDA在质量浓度为0.5~100.0μg·L^-1范围内具有良好的线性相关性,R2均大于0.9990,方法检出限依次为0.120、0.060、0.060、0.024 ng·L^-1,回收率为92.3%~104.7%,相对标准偏差(RSD)小于6.6%.本文方法具有较好的线性、灵敏度、准确度和精密度,并已成功应用于象山港海水实际样品的检测分析.

An accurate analytical method was developed for the determination of trace level of atrazine(ATR)and its major metabolites(deethylatrazine,DEA;deisopropylatrazine,DIA;didealkylatrazine,DDA)in seawater by coupling solid-phase extraction with gas chromatography tandem mass spectrometry(GC-MS/MS).The HLB solid-phase extraction(SPE)column was used to enrich and purify the target analytes in seawater.Furthermore,the parameters affecting the SPE extraction efficiency were optimized.The pH of the seawater sample was adjusted to 3 before the SPE extraction.Subsequently,the samples were analyzed by GC-MS/MS with multi-reaction monitoring mode(MRM),and the limit of detection(LOD),sensitivity,accuracy and precision were verified.Finally,the results indicated that the good linear relationship in the range of 0.5-100.0μg·L-1 with R2 above 0.9990 was obtained.The LODs of ATR,DEA,DIA and DDA were 0.12,0.06,0.06 and 0.024 ng·L-1,respectively.The excellent recoveries of ATR,DEA,DIA and DDA were in the range of 92.3%-104.7%with RSD below 6.6%.The results demonstrated that the present method has optimal linearity,sensitivity,accuracy and precision.It could be successfully applied to the analysis of four analytes in the seawater samples from Xiangshan Bay.