Direct enantiomeric separation of betaxolol with applications to analysis of bulk drug and biological samples.

A direct method is described for the resolution of the enantiomers of betaxolol, a novel cardioselective beta-adrenergic blocking agent, using a tris(3,5-dimethylphenylcarbamate)cellulose chiral column. An excellent resolution of the two antipodes is obtained (Rs greater than 2) with high peak symmetries. The method is simple and ideally suited to the routine control of the enantiomeric excess in the bulk drug and the analysis of the enantiomers of betaxolol in hepatocyte suspensions. With modification of the polar modifier in a hexane-based mobile phase, most commercially available beta-blockers can be baseline resolved.