Separation of stereoisomers of aminoglutethimide using three capillary electrophoretic techniques

• Published in: Journal of Chromatography A 1995-06, Vol.705 (2), p.343-349
• Main Authors: Anigbogu, Vincent C., Copper, Christine L., Sepaniak, Michael J.
• Format: Article
• Language: English
• ISSN: 0021-9673
• DOI: 10.1016/0021-9673(95)00292-U

A novel approach to capillary electrokinetic chromatography involving differential distribution between neutral and charged cyclodextrins is described for the separation of the enantiomeric pair of the drug aminoglutethimide. For comparison purposes, micellar electrokinetic capillary chromatography and capillary electrophoresis with neutral cyclodextrin additives are also evaluated for this separation. The three techniques are compared in terms of their ability to resolve the two enantiomers. At pH 9, where aminoglutethimide is neutral, the enantiomers were resolved using a running buffer containing 5 m M β-cyclodextrin, and 50% (v/v) methanol. At the same pH, micellar electrokinetic capillary chromatography, using a running buffer containing 50 m M sodium dodecyl sulfate and 17.5 m M β-cyclodextrin, only partially resolved the enantiomers. However, at pH 3, where aminoglutethimide is ionized, the enantiomeric pair was separated using capillary electrophoresis with either 10 m M α-cyclodextrin or 5 m M γ-cyclodextrin added to the running buffer. Enantiomeric separations, by way of the three electrophoretic capillary chromatographic techniques mentioned above, are presented and mechanisms of chiral recognition of aminoglutethimide by cyclodextrins under various experimental conditions are also discussed.