Abstract
Cation-exchange polymer-brush-immobilized particles were prepared using polyethylene particles with an average diameter of 60 μm as a starting material for electron-beam-induced graft polymerization. Typical proteins, i.e., chymotrypsinogen A, cytochrome C, and lysozyme, were loaded onto a cation-exchange polymer brush immobilized particle (cation-exchange particle)-packed bed followed by gradient elution with a mixture of phosphate buffer (pH 6.0) and 1 M NaCl. Resolution performance was compared between the cation-exchange particle and commercially available cation-exchange bead (SOURCE 30S, GE Healthcare Co.) using the respective packed heights of the bed under an identical bed pressure loss, i.e., 1.5 and 2.5 cm. Even at higher linear velocity and total protein load, the cation-exchange-particle-packed bed exhibited a higher resolution for both chymotrypsinogen A/cytochrome C and cytochrome C/lysozyme combinations than the SOURCE-30S-packed bed.