Chiral separation of duloxetine and its R-enantiomer by LC

The direct enantioseparation of duloxetine and its R-enantiomer was achieved by HPLC using hydroxypropyl-beta-cyclodextrin (HP-beta-CD) as a chiral selector and a vancomycin chiral stationary phase (Chirobiotic V). Operational parameters, such as the concentration of HP-P-CD, buffer pH, organic modifiers, temperature and flow rate, were varied in order to achieve the desired retention time and resolution. These two enantioseparation methods developed gave a baseline resolution of the enantiomers. Finally, the HPLC-CSP method was selected to determine the enantiomeric purity of duloxetine drug substance due to its much shorter analysis time and better resolution. The limit of detection of this method was 0.06 mu g mL(-1).