Development of a V-shape bis(tetraoxacalix[2]arene[2]triazine) stationary phase for High performance liquid chromatography

• A mix-mode stationary phase modified by V-shape cage oxa-calixarene was prepared.
• Study of the stationary phase via a linear solvation energy relationship model.
• Alkylbenzenes, disubstituted aromatics and flavonoids were employed as probes.
• Separation of inorganic anions in anion-exchange mode.

A new stationary phase for high-performance liquid chromatography was prepared by covalently bonding a V-shape cage heteroatom-bridged calixarene onto silica gel using 3-aminopropyltriethoxysilane as coupling reagent. The structure of the new material was characterized by infrared spectroscopy, elemental analysis and thermogravimetric analysis. Linear solvation energy relationship method was successfully employed to evaluate the new phase with a set of 34 solutes. The retention characteristic of the new phase shows significant similarities with ODS, as well as distinctive features. Multiple mechanisms including hydrophobic, hydrogen bonding, π–π and n–π interaction are involved. The chromatographic behavior of the phase was illustrated by using alkylbenzenes, aromatics positional isomers and flavonoids as probes. Moreover, inorganic anions were individually separated in anion-exchange mode by using the same column. Thus, multi-interaction mechanisms and mixed-mode separation of the new phase can very likely guarantee its excellent chromatographic performance for the analysis of complex samples. The column has been successfully employed for the analysis of clenbuterol in animal urine, and it is demonstrated to be suitable and a competitive alternative analytical method for the determination of clenbuterol.

A mixed-mode bis(tetraoxacalix[2]arene[2]triazine) stationary phase was prepared for the first time and with its separation mechanism evaluated.Figure optionsDownload as PowerPoint slide