The determination of sulfonated azo dyes in municipal wastewater by ion spray liquid chromatography tandem mass spectrometry

作者：Per Olof Edlund, Edgar D. Lee, Jack D. Henion, William L. Budde · 发表于：Journal of Mass Spectrometry · 年份：1989 · DOI：10.1002/bms.1200180405 · 被引用次数：60 · 研究领域：Dye analysis and toxicity、Analytical chemistry methods development、Water Quality Monitoring and Analysis

A liquid–solid extraction method suitable for rapid screening of sulfonated azo dyes in municipal wastewater has been developed. The dyes (Color Index Acid Yellow 23, Red 14 and Yellow 49) were separated on a short, reversedphase liquid chromatographic column with a water-methanol gradient containing 2 mM sulfuric acid. The column effluent was directed via a split-valve to an ion spray liquid chromatography/mass spectrometry (LC/MS) interface to an atmospheric pressure ionization mass spectrometer. The ion spray LC/MS system produced abundant [M – Na]− and [M – 2Na]2− ions according to the number of sulfonic acid substituents. Collision-induced dissociation of the parent ions for the dyes studied gave the SO3−. fragment common to sulfonated compounds plus additional daughter ion fragments characteristic of each dye. The dyes were quantified by monitoring from four to six different daughter ions of each dye. The relative abundances and the sum of the daughter ion current counts were used for confirmation and quantification with external standards. Recoveries of the dyes were in the range of 70–122%, and the relative standard deviation of replicate determinations was 5.4–12%. The method detection limit was three times higher for Acid Yellow 23 compared with the other two dyes, which could be detected down to 50 ppb in municipal wastewater.