Separation of α-Hydroxy Acid Enantiomers by High Performance Liquid Chromatography Using Copper(II)-L-amino Acid Eluent

Abstract

Enantiomers of underivatized α-hydroxy acids including lactic, mandelic, malic, and tartaric acids have been separated by reversed phase liquid chromatography using Cu(II) -L-amino acid complexes as eluents. The hydroxy acids in the column effluent were detected by a postcolumn color reaction with acidic iron(III) solution. Upon change in elution conditions α-hydroxy acids with another hydroxy group and/or carboxyl group in the β-position behaved quite differently from the acids with no functional group in the β-position, which indicated the involvement of more than one resolution mechanism in the present system.