Preparation and Application of Isoquinolinecarboxylic Acid Derivative as Chiral Stationary Phase for Ligand Exchange Chromatography

A novel chiral stationary phase (C16-(S)-THIQCA) for ligand exchange high-performance liquid chromatography was prepared by synthesizing 2-(2-hydroxyl) hexadecyl-(S)-1,2,3,4-tetrahydro-3-isoquinolinecarboxylic acid as a chiral selector and coating it on ODS-bonded stationary phase. The enantiomeric resolutions of 16 D,L-amino acids were achieved on C16-(S)-THIQCA by using cupric acetate aqueous solution as mobile phase, column temperature 25°C, and detection at UV 254 nm. The enantioselectivities α of the D,L-amino acids separated were found to be in the range from 1.09 to 1.67 with the resolution Rs ranging from 1.0 to 4.8. The elution order of D-isomer before L-isomer was observed for all D,L-amino acids used. The effects of chromatographic conditions including flow rate, column temperature, pH, and the concentration of Cu2+ and NH4+ on the resolutions of D,L-amino acid enantiomers were discussed.