Chemically bonded cationic β-cyclodextrin derivatives and their applications in supercritical fluid chromatography

Cationic β-cyclodextrin (CD) perphenylcarbamoylated derivatives were chemically bonded onto vinylized silica using a radical co-polymerization reaction. The derived materials were used as chiral stationary phases (CSP) in supercritical fluid chromatography (SFC). Enantioseparations were successfully demonstrated on 14 racemates encompassing flavanones, thiazides and amino acid derivatives. The electrostatic force between the analytes and the cationic moiety on β-CD derivative was found to be important for retention and enantioseparation of the racemates. Aromatic cationic moiety on β-CD enabled better enantioseparations than aliphatic cationic moiety. It was also found that the presence of acid additives would result in lower retention of the analytes but often assist the chiral resolutions.

► Cationic substituents were introduced into beta-cyclodextrin CSP and applied in SFC.
► 14 pharmaceutical compounds attained enantioseparations.
► The CSP with aromatic cationic moiety enabled better enantioseparations.
► Acid additives decrease retention of the analytes but often assist the resolution.
► Electrostatic forces and inclusion with cyclodextrin cavity worked synergistically.