Enantioseparation of Organic Acids and Monosaccharides by Novel Ligand Exchange-Capillary Electrophoresis

Capillary electrophoresis is a fast, cost-effective, and high-resolution separation technique. An advantage of ligand-exchange CE is that it is possible not only to change the chiral selector concentration, but also to mix the ligand and the central metal ion at any ratio. Chiral resolution by capillary electrophoresis was first achieved by ligand exchange, in which the Cu(II) complex with L-histidine was used as a chiral selector for the resolution of dansylated amino acids. In subsequent investigations, Cu(II) ion was generally used as the central ion. We tried to develop a novel ligand-exchange capillary electrophoresis by using a dual metal-ion system to simultaneously enantioseparate malic, tartaric and isocitric acids in juice samples, because the analysis of enantiomers and/or enantiomeric ratios in beverages can provide valuable information concerning food authenticity and adulteration. We also tried to develop another ligand-exchange capillary electrophoresis using borate anion as a central ion of the chiral selector to enantioseparate monosaccharides. In this paper, we introduce the above novel enantioseparation methods using ligand-exchange capillary electrophoresis.