液相色谱-串联质谱法同时检测自来水中9种卤乙酸

Determination of Nine Haloacetic Acids in Tap Water by Liquid Chromatography-Tandem Mass Spectrometry

建立了一种快速、灵敏分析自来水中9种卤乙酸的液相色谱一串联质谱（LC—MS／MS）同时定量检测方法。样品经O．45μm的膜过滤后，在Shim—pakXR—ODS色谱柱（3mm×75mm，2μm）上进行分离，采用甲醇-0．1％甲酸溶液梯度洗脱方式，电喷雾负离子（ESI-）模式，多反应监测模式（MRM）进行质谱分析。实验表明9种卤乙酸在检测范围内均具有良好的线性关系（帮〉0．9950），检测限（S／N〉3）为0．016～2．31μg／L，定量限（s／N〉10）为0．053～7．69μg/L；根据卤乙酸不同定量限分别进行低、中、高三个浓度梯度的空白加标实验（n=5），平均回收率为92．8％～107．2％，相对标准偏差为0．58％～12．8％；自来水基底加标实验（n=7）的平均回收率在83．9％～111．3％，相对标准偏差范围在1．6％～9．2％。该分析方法快速简便、灵敏度高、重现性好，可用于自来水中微量卤乙酸的快速检测。

A simple and rapid detection method for nine haloacetic acids （HAAs） in tap water was developed using liquid chromatography tandem mass spectrometry （LC-MS/MS）. After being filtered through a 0.45 μm membrane, the samples were separated on a Shim-pak XR-ODS column （3 mm 75 mm, 2 μm） by applying methanol and Milli-Q water （containing 0.1% formic acid） as the mobile phase with gradient elution mode. Electrospray ionization was applied and operated in the negative multiple re- action monitoring （MRM） mode. The results showed that the linear correlation coefficients （R2） were larger than 0. 995 0, the limits of detection （S/N 〉 3） were in the range of 0. 016 to 2.31 ~xg/L, and the limits of quantification （LOQ） （ S/N 〉 10） were in the range of 0. 053 to 7.69 ~g/L. According to dif- ferent LOQ, the mean recoveries of HAAs spiked at three concentration levels （n = 5） in Milli-Q water were in the range of 92.8% to 107.2% , and the relative standard deviations （RSDs） were between 0.58% and 12.8%. Furthermore, the mean recoveries of HAAs spiked at 10 txg/L in tap water （n =7） were in the range of 83.9% to 111.3% , and the RSDs were between 1.6% and 9.2%. This method is suitable for rapid detection of trace haloacetic acids in tap water for its rapidity, convenience, high sensi- tivity and good reproducibility.