Capillary zone electrophoresis for the determination of light-absorbing anions in environmental samples

A rapid and simple method for separation and determination of inorganic ani ons by capillary zone electrophoresis was described. The detection was carr ied out directly with a diode array detector. The experimental conditions, such as concentration of carrier electrolyte, capillary length, voltage, an d temperature were optimized. In order to improve selectivity, different or ganic modifiers were also investigated. The baseline separation of 10 light -absorbing anions was accomplished within 3.5 min with a background electro lyte consisting of 50 mM sodium tetraborate containing 5% MeOH. Linear plot s were obtained in the concentration range of 0.1-10 mug/ml. With sample st acking injection, the quantitation limits of the anions were found to be in the range of 0.02-0.1 mug/ml. The proposed method was successfully applied to the determination of inorganic anions in environmental samples and in e ffluents of a power plant. (C) 2001 Elsevier Science B.V. All rights reserv ed.