A Novel Affinity Support Material for the Separation of Immunoglobulin G from Human Plasma

Abstract

2‐Methacrylamidohistidine (MAH) as a pseudospecific ligand was synthesized from methacryl chloride and histidine. Spherical beads with an average size of 50–63 μm were obtained by the radical suspension polymerization of MAH and 2‐hydroxyethyl methacrylate (HEMA) conducted in an aqueous dispersion medium. Owing to the reasonably rough character of the bead surface, P(HEMA‐co‐MAH) beads had a specific surface area of 17.6 m2·g–1. Synthesized MAH was characterized by NMR. P(HEMA‐co‐MAH) beads were characterized by swelling studies, FT‐IR spectroscopy, scanning electron microscopy (SEM) and elemental analysis. P(HEMA‐co‐MAH) affinity beads with a swelling ratio of 65% were used in the separation of human immunoglobulin G (HIgG) from aqueous solutions and human plasma. The maximum HIgG adsorption on the P(HEMA‐co‐MAH) adsorbents was observed at pH 7.4 for phosphate and at pH 6.0 for morpholinoethanesulfonic acid buffers. The HIgG adsorption onto the PHEMA adsorbents was negligible. Higher adsorption values (up to 46.5 mg·g–1) were obtained when the P(HEMA‐co‐MAH) adsorbents were used in aqueous solutions. Much higher amounts of HIgG were adsorbed from human plasma (up to 73.8 mg·g–1). Adsorption capacities of other blood proteins were obtained as 3.2 mg·g–1 for fibrinogen and 4.6 mg·g–1 for albumin. The total protein adsorption was determined to be 82.2 mg·g–1. The pseudospecific affinity beads allowed one‐step separation of HIgG from human plasma. HIgG molecules could be repeatedly adsorbed and desorbed with these adsorbents without noticeable loss in their HIgG adsorption capacity.

Molecularly Imprinted PHEMA‐Based Cryogel for Depletion of Hemoglobin from Human Blood

“…[23] Briefly, 5.0 g of L-histidine methyl ester and 0.2 g of hydroquinone were dissolved in 100 mL of dichloromethane solution. This solution was cooled down to 0 8C; 12.7 g triethylamine was added followed by pouring slowly.…”

“…Recently, our laboratory developed the MAH ligand for affinity separation of proteins by introducing functional imidazole groups into polymer structure without any leakage. [23,24] The preparation of Hb imprinted cryogel was organized in three main parts. In the first part, MAH was synthesized by reacting methacryloyl chloride with L-histidine methyl ester.…”

Synthesis of tentacle type magnetic beads as immobilized metal chelate affinity support for cytochrome c adsorption

“…If the binding is attributed to monovalent interactions, the capacity increases with increase in ligand density, while the association constant may remain constant at low ligand density and decrease at high ligand density due to the steric effects [29]. Thus, there is an optimal density at which the metal ion ligands have high capacity and an acceptable extent of steric hindrance [30].…”

Affinity separation of immunoglobulin G subclasses on dye attached poly(hydroxypropyl methacrylate) beads

“…dospecific, dye-affinity and molecular sieving [2][3][4][5][6][7]. Fractionation by ethanol precipitation is the most used process to purify IgG from human plasma on industrial scale (27 tonnes/year) [8].…”