Chiral Separation of Basic and Zwitterionic Drugs by Highly Sulfated Cyclodextrins Using Short-End Injection Capillary Electrophoresis

Due to high resolution power of sulfated cyclodextrins (HS-CDs), utilization of these selectors for chiral resolution of 7 basic and 2 zwitterionic drugs have been examined. Experiments were performed on a HP3DCE instrument equipped with an on-column diode array UV absorbance detector. Fused silica capillaries with an inner diameter of 50 μm, an outer diameter of 365 μm, and a total length of 45.5 cm (8.5 cm to the detector) were used. Capillaries were rinsed with PEO once daily. To reduce analysis time, short-end injection technique was applied. The electrophoretic conditions for the stereoselective analysis of drugs were in the carrier mode with 25 mM sodium phosphate buffer containing 1.25% w/v of each HS-CD at pH 2.5 with an applied voltage of +15 kV. At these conditions, rapid enantioresolution(≤3.9 min) of all drugs were achieved.