The chiral separation of sibutramine enantiomers was resolved succesfully by capillary zone electrophoresis using cyclodextrins (CDs) as chiral selectors. A complex screening of several different native and derivatized, neutral and ionized cyclodextrine derivatives was performed. The effects of buffer type, concentration and pH, cyclodextrin type and concentration, applied voltage, capillary temperature and injection parameters on the chiral resolution were examined. The best results on a very short fused silica capillary of 30 cm × 50 μm were obtained using a 50 mmol L-1 phosphate buffer containing 10 mmol L-1 randomly methylated β-CD at a pH of 4.5, 15 kV of voltage, temperature of 15 °C, injection parameters of 30 mbar s−1 and ultraviolet (UV) detection at 220 nm. The analytical performances of the optimized method were verified in terms of linearity, precision and robustness, and limit of detection and quantification were calculated.
Keywords:
sibutramine; chiral separation; capillary electrophoresis; cyclodextrins
