Enantiomeric Separation and Determination of the Enantiomeric Impurity of Armodafinil

Ashley Kimberley

In recent years, capillary electrophoresis (CE) has been widely used for enantiomer separation and enantiomer impurity determination because of its high efficiency, rapid analysis and low cost of operation. Enantioresolution for CE is typically achieved by adding chiral selectors to the buffer. Versatile native and modified cyclodextrins (CDs) are one among the most commonly used chiral selectors for the inclusion of solute hydrophobic portions by the cavity of CDs and the weak interactions of enantiomers with CDs (such as hydrophobic interactions, hydrogen bonding and van der Waals force, etc.) resulting in differences in stability constants of temporary diastereomeric complexes. Besides, the differences in hydrodynamic resistance arising from the differences in shape, size or hydrodynamic radii, etc.