High Performance Liquid Chromatographic Separation ofLactic acid Enantiomer Using Chiral Mobile Phase Additives / 分析化学

ABSTRACT

The enantiomeric resolution of lactic acid was studied by reversed high performance liquid chromatography. β-cyclodextrin (β-CD), dimethyl (DM) and TM-β-CD were used as chiral mobile phase additives. The effects of different mobile phase, pH and concentration of chiral mobile phase additives on resolution of D,L-lactic acid were investigated. The results showed the enantioselectivity of TM-β-CD was better than those of β-CD and DM-β-CD. D,L-lactic acid could be partly separated by DM-β-CD 　and could not be separated by β-CD, while it could be fully separated by TM-β-CD. As the concentration of TM-β-CD changed from 0.20　mmol/L to 1.00　mmol/L, The resolution varied slightly. The experiment of the effect of pH of mobile phase on Rs showed as pH changed from 2.4 to 3.0, the Rs remain stable, and when pH＞3.1, the Rs decreased with the increase of pH. The RSD of retention time of L-lactic acid and D-lactic acid were 0.2% and 0.2%, respectively. The chromatographic systems with a dynamically-generated stationary phase with 2,3,6-tri-O-methyl-β-cyclodextrin proved to be an effective method for lactic acid enantiomer separation