HPLC-ESI-MS/MS检测典型废水与活性污泥中4种大环内酯类抗生素

摘要

应用超声波辅助萃取技术,联合固相萃取及高效液相色谱-电喷雾串联质谱(HPLC-ESI-MS/MS)技术建立了典型废水和活性污泥中4种大环内酯类抗生素(MLs)的高灵敏分析方法.水样经Oasis HLB萃取小柱富集、净化后以甲醇洗脱；活性污泥样品以乙腈-磷酸盐缓冲溶液为溶剂超声萃取、富集、净化.采用HPLC-ESI-MS/MS进行定量分析；流动相为乙腈-乙酸铵水溶液,采用电喷雾正电离源和选择性反应监测模式进行检测.结果表明,4种抗生素的线性范围为0.1～100 μg·L-1,相关系数均大于0.99,方法检出限为0.002～0.019 pg,废水和活性污泥样品中MLs的平均回收率分别为70.2％～90.6％和75.6％～88.7％,方法检出限分别为0.013～0.025 ng·L-1和0.09～0.22 ng·g-1.将建立的方法应用于新疆石河子市可能的抗生素污染源典型废水和活性污泥样品中4种MLs的检测,结果表明,MLs普遍存在于各废水(未检出～308.23ng· L-1)和活性污泥(未检出～120.46 ng·g-1)样品中.%A reliable,sensitive and selective method was developed for the determination of 4 macrolide antibiotics(MLs) in typical waste water and activated sludge using high performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS).The target antibiotics in water samples were enriched and cleaned up with HLB solid phase extraction cartridges,and then eluted with 6 mL methanol.The activated sludge sample was ultrasonically extracted with a mixture of acetonitrile-phosphate buffer.The eluate was collected and concentrated under a gentle stream of nitrogen gas.The target compounds were separated on a Waters Symmetry-C18 column with acetonitrile-10 mmol · L-1 ammoniumacetate as mobile phase,and analyzed by HPLC -ESI-MS/MS under positive electrospray ionization and selected reaction monitoring mode.Good linearities of 4 MLs were achieved over the concentration range of 0.1-100 μg · L-1,with correlation coefficients above 0.99.The overall recoveries of 4 MLs in waste water and activated sludge matrices were in the ranges of 70.2％-90.6％ and 75.6％-88.7％,respectively,with relative standard deviations(RSD,n =6) of 2.7％-7.8 ％.The method detection limits of 4 MLs in water samples and activated sludge were in the ranges of 0.013-0.025 ng · L-1 and 0.09-0.22 ng ·g-1,respectively.The developed method was applied in the analysis of the typical waste water and activated sludge in Shihezi,Xinjiang,and the results indicated that the target antibiotics were detected in all samples.