Separation of Carvedilol Enantiomers using HPLC by two Different Methods: Mobile Phase Chiral Additive and Chiral Stationary Phase

This paper presents the results of HPLC enantioseparation of carvedilol using HPLC by two different methods the first one is reversed phase HPLC (RP-HPLC), In which carboxy methyl-β- cyclodextrin (CM-β-CD) is used as chiral mobile phase additive the second one, which is common used, depends on using chiral stationary phase (polysaccharide type, Chiralcel OD-R column, 250 mm×4.6 mm). In mobile phase chiral additive method, the highest resolution was achieved using Knauer C18 column (250 mm×4.6 mm) and mobile phase made up of a mixture of aqueous solution [pH=4.4, (2.3g/l CM-β-CD)], methanol and acetonitrile with a volumetric ratio of (56.8/30.7/12.5) v/v%, flow rate of 0.7mL/min, and column temperature was set at 40°. In chiral stationary phase method,the mobile phase consisted of acetonitrile, isopropanol, and diethyl amine with a volumetric ratio of (95/5/0.1) v/v%, flow rate of 1 ml/min at room temperature. The effects of different conditions on the enantioseparation of carvedilol were investigated. Both methods showed good resolution of carvedilol enantiomers. But the first new one is very inexpensive comparing with the second one.