Versatility of capillary electrophoresis of anions with a high mobility chromate electrolyte

Abstract

Capillary ion electrophoresis (Waters' trade name: Capillary Ion Analysis) is a capillary electrophoretic technique which is optimized for the rapid analysis of low molecular-mass inorganic and organic ions. Indirect UV detection at 254 nm was used throughout. An electroosmotic flow modifier was added to the chromate electrolyte and a negative power supply was used. Analysis of anions in a variety of samples with differing matrices was investigated. Examples discussed include trace level anions in power plant water (ng/ml) and μ/ml level of anions in intermediate and concentrated sulfonated dyes. Anion analysis using this technique is rapid (less than 5 min), with little sample preparation required. The same electrolyte composition, with only minor variations, was used for all samples. Both hydrostatic mode of injection for ppm level analysis and electromigration mode of injection for trace level analysis was used.