Effects of Cross-Linking and Spacer Groups on beta-Cyclodextrin Bonded Liquid Chromatographic Separation

摘要

Mesoporous glass beads and 5 μm silica particles were modified with beta-cyclodextrin (β-CD) by means of directly bonding, linking spacer group, and cross-linking agent. The selectivities of the β-CD modified silica particles were measured by simple column chromatography to separate a model mixture of 1- and 2-hydroxy-naphthalene (naphthols) and ortho, meta, and para-xylene. In the packed column chromatography experiments, two major controlling factors (inclusion complex formation effect and steric hindrance effect of the analytes) on the separations were observed. The elusion orders of the β-CD directly bonded glass beads were meta-, para-, ortho-xylene and 1-naphthol, 2-naphthol. The phenomena of β-CD pore blocking and narrowing by spacer groups and cross-linking agent were observed. The spacer group and cross-linking agent decreased inclusion complex formation of 2-naphthol.