Migration Behavior of Inorganic Anions in Micellar Electrokinetic Capillary Chromatography Using a Cationic Surfactant

The Interactions between Inorganic anions and a cationic surfactant were Investigated using micellar electrokinetic capillary chromatography (MECC). Using cetyltrlmethylammonlum chloride (CTAC) as a cationic surfactant, the effective electrophoretic mobilities of Inorganic anions decreased due to two processes. The first was the Ion association equilibria with a monomeric surfactant below the critical micellar concentration (cmc) and the other was partitioning Into the micelle above the cmc. Fundamental equations for migration of Ionic species In MECC were derived using the effective electrophoretic mobility as an electrochemical parameter. Ion association constants of Inorganic anions with cationic surfactant and distribution coefficients Into the micelle were estimated on the basis of these equations.