Analytical Sciences

Abstract − Analytical Sciences, 18(1), 59 (2002).

Sulfoacylated Macro-Porous Polystyrene-Divinylbenzene Low-Capacity Cation Exchanger Selective for Amino Acids
Yukio YOKOYAMA,  Masanori WATANABE, Sohei HORIKOSHI, and Hisakuni SATO
Department of Analytical Chemistry, Faculty of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama 240-8501, Japan
A low-capacity cation-exchange column was newly developed for the separation of amino acids. A highly cross-linked macro-porous polystyrene-divinylbenzene co-polymer was functionalized by a sulfoacylation reaction. The exchange capacity was controllable at the acylation step. The capacity between 55 and 60 umol/column was adequate for the practical separations in acceptable retention times. The 5-um base polymers having average pore diameters smaller than 3 nm gave satisfactory results, and those having 1.5-nm pore was most favorable. Several isocratic elution conditions at different pH values adjusted by phosphate buffer of mM order with or without acetonitrile could provide good separations for individual classes of amino acids, i.e., acidic, neutral, hydrophobic, and basic groups. The results provided fundamental data for constructing gradient elution systems required for the simultaneous separation of protein amino acids.