Abstract: A simple and effective method for the separation of ketoconazole enantiomers was developed using the chiral mobile phase additive on a C18 reversed-phase column. Several β-cyclodextrins were investigated as chiral mobile phase additives separately. The results showed that ketoconazole enantiomers were well separated by only adding sulfobutyl ether-β-cyclodextrin （SBE-β-CD） into the mobile phase. Excellent enantioseparation was achieved with the mobile phase composed of methanol-0.02 mol/L NaH2PO4 (60∶40, v/v, containing 1.0 mmol/L SBE-β-CD and 0.02% triethylamine, at pH 3.00 adjusted with phosphoric acid aqueous solution). The flow rate was 1.0 mL/min. The detection wavelength was set at 225 nm and the column temperature at 30 ℃. Under the optimized conditions, the resolution of ketoconazole enantiomers was 2.05.

Key words: chiral mobile phase additives , ketoconazole enantiomers, sulfobutyl ether-β-cyclodextrin, high performance liquid chromatography (HPLC)