Development of an SPE/CE method for analyzing HAAs

作者：Zhang Li; Capel Paul D; Hozalski Raymond M^*

来源：Journal of the American Water Works Association (AWWA), 2007, 99(3): 83-94.

DOI：10.1002/j.1551-8833.2007.tb07891.x

A method to analyze haloacetic acids (HAAs) in drinking water was developed using a capillary electrophoresis (CE) ion analyzer for analyte separation and detection. The effects of background electrolyte (BGE) composition, sample injection approach, and on- and off-capillary preconcentration techniques on HAA peak resolution and method sensitivity were evaluated. The recommended BGE consists of 25 mM phosphate buffer at pH 5.7 with 1 mM tetradecyltrimethylammonium hydroxide as the electroosmotic flow modifier. Aqueous samples were preconcentrated using solid-phase extraction (SPE) and then loaded onto an extended light path capillary (75-mu m inside diameter x 56-cm effective length) using pressure injection (50 mbar for 12 s). The estimated method detection limits were in the range of 1.5-3.5 mu g/L. The SPE/CE method was used to analyze ambient and spiked water samples from a water distribution system, and results were in good agreement with those using US Environmental Protection Agency method 552.2. The main advantage of the SPE/CE method over the currently approved HAA analysis methods is that it does not require HAA derivatization, which involves potentially hazardous chemicals and conditions, Disadvantages of the SPE/CE method are that it does not offer a significant time savings (because of the need for off-capillary sample preconcentration) and chlorodibromoacetic acid could not be quantified because of interference from a contaminant peak.

• 出版日期2007-3