Novel hydrophobic ligand-containing hydrogel membrane matrix: preparation and application to gamma-globulins adsorption

Abstract

In this study, phenylalanine as a hydrophobic ligand was covalently attached to the co-monomer methacrylochloride. Then, poly(2-hydroxyethylmethacrylate-co-methacrylamidophenyalanine) [poly(HEMA-MApA)] membranes were prepared by UV-initiated photopolymerization of HEMA and methacrylamidophenyalanine. The gamma -globulins adsorption onto these affinity membranes from aqueous solutions containing different amounts of gamma -globulins at different pH was investigated in a batch system. The gamma -globulins adsorption capacity of the membranes was increased as the ligand density on the membrane surface increase. The non-specific adsorption of the gamma -globulins on the pHEMA membranes was negligible. The adsorption phenomena appeared to follow a typical Langmuir isotherm. The maximum adsorption capacity (q(m)) of the poly(HEMA-MAPA4) membrane for gamma -globulins was 2.37 mg g(-1) dry membrane. The equilibrium constant (k(d)) value was found to be 1.61 x 10(-1) mg ml(-1). More than 87% (up to 100%) of the adsorbed gamma -globulins were desorbed in 120 min in the desorption medium containing 50% ethylene glycol in 1.0 M NaCl. (C) 2001 Elsevier Science B.V. All rights reserved.