Enantiomeric separation of duloxetine hydrochloride by HPLC using chiral mobile phase additives

An HPLC chiral separation method for duloxetine hydrochloride enantiomers using sulphobutylether-β-CD(SBE-β-CD)as chiral mobile phase additive was developed to control the quality of bulk drug.Based on the optimization of the influential factors，including the kind and concentration of chiral additives，the pH of the mobile phase，the ratio of methanol，the HPLC separation was carried out on a Diamonsil C₁₈ column (150 mm×4. 6 mm，5 μm) with a mobile phase of 10 mg/mL SBE-β-CD (pH 2.5，adjusted by phosphoric acid)-methanol(73∶27)，the flow rate 1.0 mL/min，the column temperature 40 °C，and the detection wavelength at 230 nm.Under the established chromatographic conditions，duloxetine hydrochloride and its (-)-enantiomer could be separated completely.The standard curve of (-)-enantiomer is linear over the range of 1-50 μg/mL with the correlation coefficient of 0.999 9.The average recovery was 100.8 % (RSD=1.0 %).The resolution of the two enantiomers was up to 2.3 and the limit of quantitation for (-)-enantiomer was 0.02 μg.The method is simple，accurate，specific，and could be used in the quality control of duloxetine hydrochloride.