title: Protein A immobilized polyhydroxyethylmethacrylate beads for affinity sorption of human immunoglobulin G.
abstract: Protein A immobilized polyhydroxyethylmethacrylate (PHEMA) microbeads were investigated for the specific removal of HIgG from aqueous solutions and from human plasma. PHEMA microbeads were prepared by a suspension polymerization technique and activated by CNBr in an alkaline medium (pH 11.5). Protein A was then immobilized by covalent binding onto these microbeads. The amount of immobilized protein A was controlled by changing pH and the initial concentrations of CNBr and protein A. The maximum protein A immobilization was observed at pH 9.5. Up to 3.5 mg protein A/g PHEMA was immobilized on the CNBr activated PHEMA microbeads. The maximum HIgG adsorption on the protein A immobilized PHEMA microbeads was observed at pH 8.0. The non-specific HIgG adsorption onto the plain PHEMA microbeads was low (about 0.167 mg of HIgG/g PHEMA). Higher adsorption values (up to 6.0 mg of HIgG/g PHEMA) were obtained in which the protein A immobilized PHEMA microbeads were used. Much higher amounts of HIgG (up to 24.0 mg of HIgG/g PHEMA) were adsorbed from human plasma.
authors.affiliation: Chemical Engineering Department, Hacettepe University, Ankara, Turkey.
authors.forename: A
authors.initials: A
authors.lastname: Denizli
authors.forename: A Y
authors.initials: AY
authors.lastname: Rad
authors.forename: E
authors.initials: E
authors.lastname: Pişkin
mesh_terms: D002846:Chromatography, Affinity / Q000379:methods*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007074:Immunoglobulin G / Q000097:blood / Q000302:isolation & purification*; D008863:Microspheres; D011102:Polyhydroxyethyl Methacrylate; D013205:Staphylococcal Protein A
chemical_list: D007074:Immunoglobulin G; D013205:Staphylococcal Protein A; D011102:Polyhydroxyethyl Methacrylate