Facile liquid chromatographic enantioresolution of native amino acids and peptides using a teicoplanin chiral stationary phase.
The glycopeptide antibiotic teicoplanin is shown to be a highly effective stationary phase chiral selector for the resolution of underivatized amino-acid and imino-acid enantiomers. Fifty four of these compounds (including all chiral protein amino acids) as well as a number of dipeptides were resolved. Hydro-organic mobile phases are used and no buffers or added salts are needed in most cases. Hence the purified analytes are easily isolated in pure form, if needed, by evaporating of the solvent. The effect of pH, organic modifier type and amount are discussed. The enantioselective separation mechanism is examined using both molecular modeling and retention data. The strongest stereoselective interaction is for carboxy-terminated D-amino-acids. In case of peptides, it is not necessary for these to be a D-, D-, terminal sequence for strong interactions. In some cases, including Ala-Ala, the L-, D-, terminal sequence showed greater interaction with the teicoplanin chiral stationary phase.
Berthod
A
A
University of Missouri-Rolla, Department of Chemistry 65401, USA.
Liu
Y
Y
Bagwill
C
C
Armstrong
D W
DW
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis / Q000302:isolation & purification*; D002853:Chromatography, Liquid / Q000379:methods*; D008969:Molecular Sequence Data; D010455:Peptides / Q000032:analysis / Q000302:isolation & purification*; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism; D017334:Teicoplanin / Q000737:chemistry*
D000596:Amino Acids; D010455:Peptides; D017334:Teicoplanin