Abstract: | Abstract Capillary electrophoresis (CE) was developed in order to effect rapid, specific determination of potassium, calcium, sodium, and magnesium. Ions (4 cations, 1 anion) were measured continuously via shifting of samples from the inlet electrode to the outlet electrode; moreover, samples were subjected to indirect and direct ultraviolet (UV) techniques, respectively. For the measurement of cations, imidazole (5 mM) functioned as a UV absorber of indirect detection at 214 nm. Consequently, anions can be measured directly by UV at 214 nm. Separation times of cations and Cl? anions were 10 min and 2 min, respectively; the detection limit of each ion (chloride, magnesium, sodium, calcium, and potassium) was 0.1 µmol/L. This approach is very simple; additionally, measurement time is extremely short. As a result, the proposed method is suitable for routine assay of electrolytes in pharmaceutical preparations. |