反相固相萃取/超高效液相色谱-串联四极杆质谱仪同时测定污水中9种卤乙酸的方法研究

使用反相固相萃取预处理与超高效液相色谱-串联四极杆质谱仪(RSPE UPLC-MS/MS)联用建立了同时测定污水中9种卤乙酸(HAAs)的分析方法。研究表明:ENVI-C18固相萃取小柱能有效去除污水样品中有机基质的干扰,样品pH值调至2.5能有效消除无机离子对HAAs离子化的影响;采用HSST3(2.1 mm×100 mm)色谱柱,以甲醇和0.000 5%甲酸为流动相,可在15.0 min内将9种HAAs分离且效果良好。采用优化后的程序建立标准曲线,9种HAAs的线性范围为0.5~100μg/L,相关系数(r2)为0.999 7~0.999 9,检出限和定量下限分别为0.02~0.26μg/L和0.05~0.86μg/L,日内和日间相对标准偏差分别为1.4%~10.0%和1.7%~10.0%。3个污水处理厂出水在2.5μg/L和10μg/L的加标浓度水平下,回收率为85.2%~107.8%。该方法能够满足污水处理厂出水中9种HAAs的检测要求。

Determination of Nine Haloacetic Acids in Wastewater Effluents Using Reverse Solid phase Extraction Pretreatment and Ultra performance Liquid Chromatography-Tandem Mass Spectrometry

A rapid method for the determination of nine haloacetic acids(HAAs) in wastewater effluent was established using reverse-phase solid-phase extraction pretreatment coupled with ultra-performance liquid chromatography-tandem mass spectrometry(RSPE UPLC-MS/MS).An ENVI-C18 cartridge was employed to remove organic substances in water sample to minimize its negative effect on HAAs analysis,and the pH value of sample was adjusted to 2.5 to eliminate the effect of inorganic ions on the ionization of HAAs.Under the optimal conditions,all the nine HAAs were separated within 15.0 min on a reversed phase liquid chromatographic column(HSS T3,2.1 mm×100 mm) using methanol-0.000 5% formic acid as mobile phase.The calibration curves were linear(r2=0.999 7-0.999 9) in the range of 0.5-100 μg/L for all the nine HAAs.The limits of detection(LODs) and limits of quantitation(LOQs) were in the range of 0.02-0.26 μg/L and 0.05-0.86 μg/L,respectively.The intra-day and inter-day relative standard deviations(RSDs) were in the range of 1.4%-10.0% and 1.7% -10.0%,respectively.The method recoveries ranged from 85.2% to 107.8% for effluent samples from three wastewater treatment plants at two spiked concentration levels of 2.5 μg/L and 10 μg/L.This method could meet the detection requirements for nine kinds of HAAs in wastewater effluents.