Boronic acid functionalized adsorbents for antibody removal

Abstract

In this study a novel approach was developed to obtain an efficient separation of human-IgG from human plasma. 4- Vinylphenylboronic acid (VPBA) and 2-hydroxyethylmethacrylate (HEMA) were chosen as monomers. Spherical microbeads with an average size of 100-140 μm were obtained by the radical suspension polymerization of VPBA and HEMA conducted in an aqueous dispersion medium. VPBA monomer was characterized by FTIR. p(HEMA-VPBA) beads were characterized by swelling studies, FTIR and SEM. The pHEMA and p(HEMA-VPBA) microbeads were contacted with blood in in-vitro systems. Loss of the blood cells and the clotting times were also followed. Good blood compatibility properties of both pHEMA and p(HEMA-VPBA) were clearly observed with blood coagulation experiments. Loss of cells in the blood contacting with pHEMA and p(HEMA-VPBA) microbeads were nearly the same. These VPBA containing p(HEMA-VPBA) microbeads with a swelling ratio of 57 % were used in the adsorption/desorption of human-IgG from aqueous solutions and human plasma. The maximum human-IgG adsorption (139 mg/g polymer) was observed at pH 8.5 for HEPES buffer. IgG adsorption from human plasma was 38.75 mg/g. It was also observed that human-IgG could be repeatedly adsorbed and desorbed with p(HEMA-VPBA) microbeads without significant loss in the adsorption capacity.