Liquid Chromatography with Aminopropylsilica Gel Modified by Heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin Derivative

Abstract
New stationary phases modified by heptakis(2,3,6-O-trimethyl)-β-cyclodextrin were prepared and tested as HPLC columns. The results show that these stationary phases exhibit significant chiral separation abilities for various types of aromatic compounds under reversed-phase conditions. Acetylation and propionylation of the residual amino groups on silica gel improve the retention capacity of the stationary phase and results in better chromatographic chiral separation. One of the most possible reasons for this superior chiral separation observed for the acylated stationary phases is considered to be the increased local concentration of the solutes on the hydrophobic surface of the stationary phase, which increases the possibility for the contact of solutes with the outside of cyclodextrin fixed on the silica gel.