Use of beta-cyclodextrin bonded phase with s-triazine moiety in the spacer for separation of aromatic carboxylic acid isomers by high-performance liquid chromatography.
The separation and retention behavior of five aromatic carboxylic acid isomers was investigated by means of high-performance liquid chromatography (HPLC) using a beta-cyclodextrin bonded phase with s-triazine ring in the spacer. The influence of mobile phase pH on the retention was examined. The presence of s-triazine moiety in the spacer enhances greatly the selectivity of the isomers of aromatic carboxylic acids. Baseline separations of the five aromatic carboxylic acid isomers were achieved. In particular, the isomers of toluic, aminobenzoic, nitrobenzoic and hydroxybenzoic acid were successfully and effectively separated. The chromatographic results indicate that, in addition to inclusion complexation, pi-pi interaction and hydrogen bonding interaction between the bonded phase and analytes play significant roles in the retention of these acid isomers. Different elution orders were observed for these acidic solutes with different substituents. Possible retention mechanisms are discussed.
Lin
Chen-Hsing
CH
Department of Applied Chemistry, Fooyin University, Kaohsiung County, Taiwan.
Chen
Chih-Yu
CY
Chang
Shu-Wen
SW
Wu
Jong-Chang
JC
Lin
Ching-Erh
CE