Enantiomer separations by capillary electrochromatography using chiral stationary phases

Area of Science:

• Analytical Chemistry
• Separation Science

Background:

• Chiral separations are crucial for pharmaceuticals.
• Conventional High-Performance Liquid Chromatography (HPLC) faces limitations in enantiomeric resolution.
• Capillary Electrochromatography (CEC) offers a promising alternative for efficient separations.

Purpose of the Study:

• To investigate the applicability of Capillary Electrochromatography (CEC) for enantiomer separations.
• To evaluate the performance of OD type chiral stationary phases in a CEC system.
• To compare CEC separation efficiency with traditional HPLC methods.

Main Methods:

• Utilized OD type packing materials (3 and 5 microm particle diameters) as chiral stationary phases.
• Packed chiral materials into a 100 microm internal diameter fused-silica capillary using a pressurized method.
• Employed acidic or basic solutions with acetonitrile as mobile phases for separations.

Main Results:

• Successfully resolved various racemic enantiomers, including acidic, neutral, and basic drug components.
• Demonstrated superior separation efficiencies in the chiral CEC system compared to HPLC for certain enantiomers.
• Achieved low plate heights (8-13 microm) and reduced plate heights (1.6-2.6), indicating high system efficiency.

Conclusions:

• OD type packing materials are highly effective as chiral stationary phases in CEC.
• CEC provides a highly efficient platform for enantiomer separation, surpassing HPLC in some cases.
• This chiral CEC system is suitable for the resolution of diverse drug enantiomers.