SEPARATION OF STRUCTURAL ISOMERS USING CYCLODEXTRIN-POLYMERS COATED ON SILICA BEADS

Several beta-cyclodextrin (CD)-bonded stationary phases for high perfo rmance liquid chromatography (HPLC) were prepared, based on silica bea ds coated with a poly(alkylamine), [poly(ethyleneimine) (PEI)]. In ord er to obtain stationary phases with a high content of CD and maximum a ccessibility of the CD cavity, the functionalization was carried out a fter the coating, using the mono-tosyl derivative of CD as the interme diate. The ability of these supports to separate ortho, meta and para isomers of some disubstituted benzene derivatives was examined. The co ntribution of the amino groups of the polymer and of the CD cavity to the separation process is discussed. The resolution is mainly based on the difference in the stability of the complexes of the various isome rs with CD. The influence of the amount of CD on the height of the the oretical plate is also studied.