title: Peptide separation by pH-zone-refining countercurrent chromatography.
abstract: Peptides without protecting groups have been successfully separated by pH-zone-refining countercurrent chromatography (CCC) using an ion-pair reagent, di-(2-ethylhexyl)phosphoric acid (DEHPA), as a modifier in the stationary phase. Preliminary studies indicated that two parameters, i.e., the DEHPA concentration in the stationary phase and hydrophobicity of the solvent system should be adjusted according to the hydrophobicity of the analytes. Hydrophobic and hydrophilic groups of dipeptides were each separated under optimized conditions. The method was successfully applied to gram-quantity separations of bacitracin complex and bovine insulin.
authors.affiliation: Laboratory of Biophysical Chemistry, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892 1676, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Ma
authors.forename: Y
authors.initials: Y
authors.lastname: Ito
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis; D001414:Bacitracin / Q000032:analysis; D002417:Cattle; D003377:Countercurrent Distribution / Q000295:instrumentation / Q000379:methods; D006863:Hydrogen-Ion Concentration; D007328:Insulin / Q000032:analysis; D007536:Isomerism; D010755:Organophosphates / Q000032:analysis / Q000737:chemistry; D010455:Peptides / Q000032:analysis* / Q000737:chemistry; D012997:Solvents / Q000032:analysis / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D007328:Insulin; D010755:Organophosphates; D010455:Peptides; D012997:Solvents; D001414:Bacitracin; C007377:di-2-(ethylhexyl)phosphoric acid