MIGRATION ORDER REVERSAL OF ENANTIOMERS IN CAPILLARY ELECTROPHORETIC SEPARATION

Optical resolution of 4-[(5,6-dimethoxy-1-indanon)-2-yl]methylpiperidi ne (E2020) was achieved by cyclodextrin-modified capillary zone electr ophoresis (CD-CZE) and cyclodextrin-modified micellar electrokinetic c hromatography (CD-MEKC). We intend to use the CD-MEKC mode to reverse the migration order of an enantiomer in the CD-CZE mode. For the (S)-e nantiomer sample, including a varying amount of the (R)-enantiomer, th e limit of quantitation (LOQ) was 3.0% in the CD-CZE mode, where the ( S)-enantiomer migrated faster than the (R)-enantiomer, while it was 0. 8% in the CD-MEKC mode, where the migration order of these enantiomers was reversed. It is quite useful to choose these two modes properly i n order to obtain the precise optical purity. This technique is expect ed to be applied to optical purity tests of other chiral pharmaceutica ls.