Protein a Carrying Monosize PMMA Microbeads for the Removal of HlgG from Human Plasma

Abstract

Protein A-incorporated polymethylmethacrylate (PMMA) microbeads were investigated for specific removal of HlgG from human plasma. The microbeads were prepared by a phase inversion polymerization, and activated by periodate oxidation. Protein A was then incorporated by covalent binding onto these microbeads through hydroxyl groups coming from the stabilizer. The amount of incorporated protein A was controlled by the initial concentrations of protein A in the immobilization medium and pH. The maximum protein A immobilization of 0.615 mg protein A/g PMMA, was observed at a pH of 9.5 corresponding to an initial protein A concentration of 0.1 mg/ml. There was no HlgG adsorption onto the plain PMMA microbeads, while high HlgG adsorptions of up to 32 mg HlgG/g PMMA were achieved with human plasma.