Separation of drug stereoisomers by capillary electrophoresis with cyclodextrins

Using capillary electrophoresis, the enantiomers and isomers of several chiral drug molecules were resolved with cyclodextrins. Parameters affecting the resolution between (+)- and (−)-epinephrine, such as pH, cyclodextrin concentration, buffer concentration, and capillary dimensions were investigated. In addition to this, the effect of cyclodextrin type (β and several derivatized β-cyclodextrins) on resolution between stereoisomers of several chiral drug was also investigated. This study showed that the structural features of the molecule, the derivative groups on the cyclodextrin, the buffer composition and the capillary dimensions influence resolution. The chiral drugs used in this study were propranolol, atenolol, betaxolol, dipivefrin, AL03152 (an aldose reductase inhibitor), AL03363 (an oxidation product of AL03152) and the cis/trans isomers of pilocarpine.