Development and robustness testing of a nonaqueous capillary electrophoresis method for the analysis of nonsteroidal anti-inflammatory drugs

Nine non steroidal anti-inflammatory drugs were simultaneously separated by nonaqueous capillary electrophoresis with a methanol-acetonitrile (40:60, v/v) mixture containing 20 mM ammonium acetate. The effect of solvent compo sition, electrolyte nature and concentration on the electrophoretic behavio r of the selected drugs was systematically studied. Investigated electrolyt es were ammonium, lithium and sodium acetate. Modification of the solvent a nd/or the electrolyte composition was found to alter the migration order of the pharmaceutical drugs. Finally, to assess method robustness, three sens itive electrophoretic parameters as well as their interactions were evaluat ed using a full factorial design at two levels. (C) 2000 Elsevier Science B .V. All rights reserved.