Novel instrumentation for measurement of diffusion coefficient by capillary zone electrophoresis and its application to aqua lanthanide ions

The novel, modified instrumentation of a capillary zone electrophoresis (CZE) system and theory are proposed for the measurement of diffusion coefficient. The solute zone in capillary tubing is forced back and forth repeatedly by the aid of negative and positive applied high voltage, respectively, and the peak widths are recorded for the estimation of diffusion coefficient. The diffusion coefficients of Ce(III) and Cu(II) in aqueous solution were determined, and the former hydration number of Ce(III) was estimated by comparison with both diffusion coefficients.