title: Separation of alpha-hydroxy acid enantiomers by high performance capillary electrophoresis using copper(II)-L-amino acid and copper(II)-aspartame complexes as chiral selectors in the background electrolyte.
abstract: Optical isomers of some alpha-hydroxy acids, namely 2-, 3-phenyllactic acid, mandelic, p-hydroxy-, m-hydroxy and 3,4-di-hydroxymandelic acid, were separated by means of capillary zone electrophoresis in free solution, using copper (II) complexes with L-amino acid or aspartame ligands in the background electrolyte. The concentration and the pH dependence of the enantiomer separations have been studied in the cases of different chiral ligands and/or analytes. With the use of L-proline as ligand only the optical isomers of 3-phenyllactic acid were resolvable, whereas using L-hydroxyproline the D and L forms of all compounds, except for 2-phenyllactic acid, were separated. Better results were obtained with aspartame as chiral ligand.
authors.affiliation: Istituto di Cromatografia del C.N.R. Roma, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Desiderio
authors.forename: Z
authors.initials: Z
authors.lastname: Aturki
authors.forename: S
authors.initials: S
authors.lastname: Fanali
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D001218:Aspartame / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D004573:Electrolytes; D004586:Electrophoresis / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D006880:Hydroxy Acids / Q000302:isolation & purification*; D006909:Hydroxyproline / Q000737:chemistry; D015394:Molecular Structure; D011392:Proline / Q000737:chemistry; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D013696:Temperature
chemical_list: D000596:Amino Acids; D004573:Electrolytes; D006880:Hydroxy Acids; D003300:Copper; D011392:Proline; D006909:Hydroxyproline; D001218:Aspartame