The effects of the cyclodextrin (CD) type on the enantioseparation of six chiral drugs were investigated, using 2 natural CD, namely beta-CD and gamma-CD, 2 commonly used uncharged functionalized CD, namely hydroxypropylated beta-CD (HP-P-CD) and dimethylated beta-CD (DM-beta-CD), and 3 newly-developed charged CD, namely highly sulfated alpha-CD (HS-alpha-CD), highly sulfated beta-CD (HS-beta-CD), highly sulfated gamma-CD (HS-gamma-CD) as capillary zone electrophoresis additive, respectively. While the 2 natural CD showed no enantioselectivity of the 6 chiral drugs, the functionalized CD's enantioselectivity improved greatly. In particular, the HS-beta-CD could baseline chirally resolved the enantiomers of all the 6 chiral drugs, indicating that the HS-beta-CD is a versatile chiral selector and is worth developing further. The effects of the pH of the background electrolyte and the organic modifier on the enantioseparation were also examined and disscussed.
