Abstract: Separations of phenothiazines, promethazine(PZ), dioxypromethazine(OZ), chlorpromazine(CZ), trifluoperazine(TfZ) and thioridazine(TZ) by capillary electrophoresis in water and FA media were carried out and compared. Thus different selectivity and resolution were observed as media varying from water to FA. Migration order was PZ, OZ, CZ and TZ in water but (TZ+PZ), CZ and OZ in FA, when the same buffer, 25 mmol/L Tris and 25 mmol/Lcitric acid, was used. It also has been observed that pH has great effect on selectivity both in water and FA and a possible explanation was given. Separation efficiency was higher in FAmedia than in water because of the permission of high voltage applied. For all separations in FA 30kV was applied, and when 25mmol/L Tris was used as buffer, current was only 20 A and complete separation of TZ, CZ, PZ and OZ was achieved with effencicy higher than 3.5×10⁵theoretical plates for all analytes. The high performance of capillary electrophoresis in FA suggests that FAis an exc.

Key words: Capillary electrophoresis, Nonaqueous media, FA, Phenothiazinesellent media separation