Determination of Haloacetic Acids in Drinking Water Using Ultra Performance Liquid Chromatography Coupled with Solid phase Extraction

KeyWord:haloacetic acids  solid phase extraction  ion pair  ultra performance liquid chromatography  drinking water

Abstract:

      An ultra performance liquid chromatography£¨UPLC£©coupled with solid phase extraction£¨SPE£© method was established for the determination of nine haloacetic acids£¨HAAs£© in drinking water. The experimental conditions of UPLC and SPE were optimized. Three SPE cartridges with different sorbents were tested,and Lichrolut EN cartridges showed the best recoveries. A good baseline separation of target compounds were obtained in 6 minutes when using methanol and triethylamine phosphate buffer£¨pH 5.0£© as mobile phase,triethylamine as ion pair reagent. The calibration curves of nine HAAs were linear in the certain concentration range with correlation coefficients of 0.995 7 -0.999 9. The limit of detection£¨LOD,S/N¡Ý3£© for monochloroacetic acid£¨MCAA£© was 10.85 ¦Ìg/L,and those for rest of target compounds were between 0.25 ¦Ìg/L and 0ª±70 ¦Ìg/L. Recoveries of HAAs at three spiked concentration levels ranged from 60% to 106% except for MCAA. The relative standard deviations£¨RSDs,n=5£© of the method were between 2.0% and 5.7%. This method was applied in the determination of HAAs in tap water samples from a northern city in China,and five HAAs were detected.Therefore,the method was sensitive and convenient,and could be used in the trace determination of HAAs in drinking water.