Ells B, Barnett DA, Purves RW, Guevremont R
University of Alberta, Edmonton, Canada.
Anal Chem. 2000 Oct 1;72(19):4555-9. doi: 10.1021/ac000341v.
A combination of electrospray ionization, high-field asymmetric waveform ion mobility spectrometry, and mass spectrometry (ESI-FAIMS-MS) was used for the analysis of a solution containing a mixture of the nine chlorinated and brominated haloacetic acids. For a carrier gas of nitrogen in the FAIMS analyzer, haloacetate anions of the mono- and dihalogenated acids and the decarboxylated anions of three of the trihalogenated acids were detected. No signal was observed for bromodichloroacetic acid (BDCAA) at a dispersion voltage of -3400 V. The addition of a small amount of carbon dioxide to the nitrogen carrier gas resulted in the detection of the pseudomolecular trihaloacetate anions, including BDCA-, and significant increases in sensitivities for the trihalogenated species. The addition of carbon dioxide to the nitrogen carrier gas had little effect on the mono- and dihalogenated anions. Quantitative analysis of the nine haloacetic acids, using flow injection, gave detection limits between 5 and 36 parts-per-trillion in 9/1 methanol/water (v/v) containing 0.2 mM ammonium acetate.
采用电喷雾电离、高场不对称波形离子迁移谱和质谱联用技术（ESI-FAIMS-MS）分析含有9种氯代和溴代卤乙酸混合物的溶液。对于FAIMS分析仪中的氮气载气，检测到了单卤代和二卤代酸的卤乙酸根阴离子以及三种三卤代酸的脱羧阴离子。在-3400 V的分散电压下，未观察到溴二氯乙酸（BDCAA）的信号。向氮气载气中添加少量二氧化碳后，检测到了包括BDCA-在内的假分子三卤乙酸根阴离子，并且三卤代物种的灵敏度显著提高。向氮气载气中添加二氧化碳对单卤代和二卤代阴离子影响很小。采用流动注射法对9种卤乙酸进行定量分析，在含有0.2 mM乙酸铵的9/1甲醇/水（v/v）中，检测限为5至36万亿分之一。
