Band broadening in high-performance liquid chromatographic separations of enantiomers with swollen microcrystalline cellulose triacetate packings: I. Influence of capacity factor, analyte structure, flow velocity and column loading

Abstract

The peak dispersion in high-performance liquid chromatographic columns packed with swollen crystalline cellulose triacetate was investigated as a function of the capacity factors of the analytes and their structures as well as of the flow-rate, column loading and degree of cross-linking of the adsorbent material. The main contribution to the plate height is attributed to the packed bed, arising from slow adsorption/desorption processes at certain, narrow parts of the surface. The results show the existence of at least two types of adsorption sites, which differ in the rate of the adsorption/desorption process: “quick”-type and “slow”-type sites. These types of sites are assumed to differ also in the types of interactions with the analytes. The narrow, “slow”-type sites are of decisive importance for chiral recognition.