Metal analysis with capillary zone electrophoresis.

Capillary electrophoresis has recently attracted considerable attention as a promising analytical technique for metal ion separations. Significant advances in various auxiliary separation principles have opened new application areas for capillary electrophoresis in the analysis of metal species. These advances are mainly due to complexation, ion pairing, solvation and micellization interactions between metal analytes and electrolyte additives, which alter the separation selectivity in a broad range. Likewise, many separation studies on metal ions have been concentrated on the use of pre-electrophoresis derivatization methodology. Approaches suitable for improvement of selectivity for different metal species including metal cations, metal complexes, metal oxoanions and organometallic compounds are discussed, with special attention paid to the related electrophoretic system variables using illustrative examples.