SEPARATION AND ANALYSIS OF CYCLODEXTRINS BY CAPILLARY ZONE ELECTROPHORESIS

alpha-, beta-, and gamma-Cyclodextrins were separated by capillary zon e electrophoresis using indirect UV photometric detection. The cyclode xtrins are separated and detected after complexation with benzoic acid or benzoic acid derivatives using a constant electroosmotic flow. Enh anced resolution of mixtures of cyclodextrins was obtained by adjustin g the pH of the electrolyte and the concentration of benzoic acid. Hig h pH conditions resulted in short analysis times with a low selectivit y, whereas high benzoic acid concentrations resulted in long analysis times with a high selectivity. Detection limits were found at 50 mu M for alpha-, beta-, and gamma-cyclodextrins, respectively. The method a llows the separation and analysis of cyclodextrins in complex samples such as fermentation broth, urine, plasma, and pharmaceutical formulat ions with minimal sample pretreatment. (C) 1997 Elsevier Science Ltd.