Isoleucine ionic liquids as additives to separate mandelic acid and their derivative enantiomers by HPLC

Abstract

Amino acid ionic liquids (AAILs) have drawn great interest recent years in analytical chemistry due to their potential in separation. In this study, functional isoleucine ionic liquid was synthesized and used as novel chiral ligands coordinated with Cu(II) in chiral ligand exchange chromatography. Enantiomers of mandelic acid and their derivatives all showed the signs of separation. The influential factors, such as the content of methanol modifier, the concentration of isoleucine ionic liquid, the ratio of isoleucine ionic liquid and copper ion, flow rate and temperature on the separation were investigated.