Chiral separation of amino acids derivatised with fluorescein isothiocyanate by single isomer derivatives 3-monodeoxy-3-monoamino-β- and γ-cyclodextrins: the effect of the cavity size

Thirteen enantiomeric pairs of α-amino acids derivatised with fluorescein isothiocyanate (FITC-AAs) were separated in capillary electrophoresis (CE) using as chiral selectors the single isomer derivatives (SIDs) 3-monodeoxy-3-monoamino-β- and γ-cyclodextrins. The chiral separation data obtained by these strictly homologous compounds, show different behaviours, allowing to hypothesise a possible structure of the obtained selector–analyte complexes, as well as highlighting the crucial role of the cavity size and the significant effects on the resolution obtained by small differences in the structural characteristics of these analytes.

► Chiral separation of thirteen different enantiomeric pairs of fluorescein isothiocyanate derivatives of amino acids in capillary electrophoresis. ► Use of two different single isomer derivatives of cyclodextrins as chiral selectors. ► Effect of the cavity size by comparison between the behaviours of the two cyclodextrins. ► Influence of the kind of derivatisation of amino acids on the separation. ► Influence of the side chain of the amino acids on the separation of each racemate.