Preparative Liquid Chromatographic Separation of Amino Acids and Peptides on Amberlite XAD-4

Abstract

Amberlite XAD-4, a polystyrene-divinylbenzene copolymic reversed phase adsorbent which has a 750 m²/g surface area and 50Å porosity, was used as the stationary phase for the preparative liquid chromatographic separation of amino acids and peptides. Mixtures of > 40 mg and > 100 mg sample load were separated on 8.0 and 20.5 mm i.d. columns, respectively. Mixed solvent and acidic and basic solutions which cannot be used with silica and alkyl-modified silica, were evaluated as mobile phases. Mixtures of amino acids, diastereomeric di-and tri-peptides, diastereomeric dipeptides obtained from the reaction of tert-butyloxycarbonyl-L-amino acid-N-hydroxysuccinimide esters with D, L-amino acids, and enkephalin peptides were separated. Major and minor sample components were isolated.