In this study, our three recently synthesized regiospecifically monosubstituted carboxymethyl-a-cyclodextrins (CMACDs) were successfully applied for the enantiomeric separation of several biologically important low-molecular weight compounds by capillary electrophoresis. The enantioselectivity of the individual monosubstituted CMACDs added into the background electrolyte (BGE) was studied and compared with the mixture of three monosubstituted CMACDs and with native a-cyclodextrin at pH of the BGE ranging from 2.5 to 11.
Our experiments revealed a significant influence of the position of the carboxymethyl group on the a-cyclodextrin skeleton on the enantioselectivity for all the studied analytes. Interestingly, the least common 3I-O regioisomer was revealed as the most effective chiral selector.