Non-ionic surfactant modified ligand exchange chromatography using copper (II) complex of N,N-dimethyl-L-phenylalanine as the chiral additive for enantioselective amino acids separation

Anal Chim Acta. 2010 Mar 17;663(1):109-16. doi: 10.1016/j.aca.2010.01.047. Epub 2010 Feb 1.

Abstract

The influence of non-ionic surfactants on the selectivity and retention in the ligand exchange chromatography for the enantioselective separation of racemic mixtures of the amino acids dl-methionine, dl-leucine, dl-valine and dl-tyrosine applying chiral mobile phases was investigated, whereas five different surfactants were tested as modifiers. The experiments were carried out using a commercially available non-chiral RP-C8 column and the copper (II) complex of N,N-dimethyl-l-phenylalanine as the chiral additive. Varying the surfactant concentrations the retention factors and the selectivity could be controlled and in general no negative influence on the separation (due to surfactant adsorption on the non-chiral stationary phase) occurred. Changing the temperature the van't Hoff plots were obtained and the thermodynamic parameters calculated. Temperature had influence on the selectivity for each surfactant and lowered the retention times as expected.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / isolation & purification*
  • Chromatography, High Pressure Liquid
  • Ligands
  • Organometallic Compounds / chemistry*
  • Phenylalanine / analogs & derivatives*
  • Phenylalanine / chemistry
  • Stereoisomerism
  • Surface-Active Agents / chemistry*

Substances

  • Amino Acids
  • Ligands
  • N,N-dimethyl-phenylalanine
  • Organometallic Compounds
  • Surface-Active Agents
  • cupric acetate
  • Phenylalanine