Direct separation and optimization of timolol enantiomers on a cellulose tris-3,5-dimethylphenylcarbamate high-performance liquid chromatographic chiral stationary phase.

A high-performance liquid chromatographic method was developed for the direct resolution and optimization of the separation of timolol enantiomers. The method involves the use of a cellulose tris-3,5-dimethylphenylcarbamate chiral stationary phase (OD-Chiralcel) column. The effects of concentration of 2-propanol, various aliphatic alcohols and diethylamine in the mobile phase and column temperature on the retention and enantioselectivity of timolol enantiomers were studied. The maximum resolution factor obtained was 4.00 when using the solvent system hexane-2-propanol (95:5) containing 0.4% (v/v) diethylamine at 5 degrees C.