Quantitative determination of sulfur-containing anions in complex matriceswith capillary electrophoresis and conductivity detection

The analysis of sulfur species in complex matrices, like environmentally re lated samples, requires selective and sensitive as well as robust determina tion methods. As many as possible different anions need to be quantified in a reasonable analysis time. Besides ion chromatography, capillary electrop horesis has proven to be a very efficient technique for the separation and determination of ionic compounds. With the advantages of less sample and so lvent consumption compared to conventional LC, short separation time, inexp ensive and robust capillaries, CE was used to separate the anions sulfate, sulfite, thiosulfate, thiocyanate and sulfide. Detection and injection mode s and the composition of the separation buffers have been varied to find th e most suitable conditions. Conductivity detection after electrokinetic sam ple injection and improvement of calibration linearity allowed the determin ation of sulfur containing anions with low limits of detection (8 to 50 mu g/l) The developed CE method was applied to the analysis of water from an o pen-pit mining lake. (C) 1999 Elsevier Science B.V. All rights reserved.