Single-step fabrication of a teicoplanin functionalized organic-silica hybrid monolith for enantioseparation by nano-liquid chromatography

Abstract

A novel teicoplanin functionalized organic-silica hybrid chiral monolithic column was prepared by a facile single-step approach. The conditions for the preparation of the organic-silica hybrid chiral monolithic column were systematically optimized, including the amount of poly (ethylene glycol) (PEG) and urea, the tetramethyl orthosilicate (TMOS)/3-(trimethoxysilyl)-propylmethacrylate (γ-MAPS) ratio (v/v), the content of teicoplanin-2-isocyanatoethyl methacrylate (Tei-ICNEML) monomer, and the reaction temperature and time. The optimum column exhibited satisfactory efficiency, permeability and stability. In order to obtain satisfactory enantioseparation performance, reversed phase (RPM) and polar organic phase (POM) modes were employed, and different experimental conditions were optimized, such as buffer concentration and pH, amount of the organic solvent, concentration and ratio of TEA/HAc, and MeOH/ACN ratio. The stability of the Tei-ICNEML organic-silica hybrid monolithic column was also investigated in both POM and RPM separation modes. Then, this novel monolithic column was successfully applied to achieve the enantioseparation of amino alcohols, N-derivatized amino acids and mandelic acids. 15 out of 20 amino alcohols were baseline separated with good column efficiency in the POM mode, and 3 out of 5 mandelic acids and 5 out of 6 N-derivatized amino acids were baseline separated in the RPM mode.

Keywords

• Teicoplanin organic-silica hybrid monolith
• Enantioseparation
• Nano-LC
• Amino alcohols and amino acids
• Mandelic acids