Determination of sulphonated azo dyes in water and wastewater

An overview of current analytical methodologies for the determination of sulphonated azo dyes in environmental samples is presented. Conventional analytical methods involving liquid chromatography and mass spectrometry with the thermospray (TSP) interface are reviewed, as well as the newly developed methods using atmospheric pressure ionisation (API) interfaces. The combination of capillary electrophoresis with mass spectrometry (CE-MS) as a new alternative for the analysis and confirmation of polar compounds (and particularly the sulphonated azo dyes) in environmental samples is also discussed. Finally, the extraction and preconcentration of sulphonated azo dyes from water samples involving various solid phase extraction cartridges are commented upon. (C) 1997 Elsevier Science B.V.