FACTORS AFFECTING THE SEPARATION OF INORGANIC METAL-CATIONS BY CAPILLARY ELECTROPHORESIS

Various alkali metals, alkaline earth metals, transition metals and lanthanides were separated by capillary electrophoresis, and factors influencing the separations were studied. The reproducible separation of fifteen metal cations was completed in 8 min. The detection system showed a linear relationship between peak area and analyte concentration. To permit the use of indirect photometric detection and to ensure symmetrical peak shapes, a highly UV-absorbing amine having an electrophoretic mobility similar to those of the analyte cations was chosen as the major component of the electrolyte. Complexing compounds were added to the electrolyte to maximize selectively the differences in the apparent mobilities of the cations and enhance the separations.