Study of imidazole performance as pseudo-affinity ligand in the purification of IgG from bovine milk.

Abstract The spherical sepharose CL-6B beads were activated by epichlorohydrin in different epoxy contents (80, 120 and 160 μmolepoxide/mLgel) and, L-histidine and imidazole as pseudo-affinity ligands were covalently immobilized to them. Some linkers with different length, (1,2-ethanediol diglycidyl ether and 1,4-butanediol diglycidyl ether) were synthesized for activation of sepharose and the activated sepharose beads modified with imidazole and the performance of these adsorbents in the purification of immunoglobulin G from bovine milk were evaluated. Among the L-histidine bearing adsorbents, higher adsorption of IgG (0.28 mg/mL) was obtained by adsorbent with the lower concentration of L-histidine. The highest amount of IgG adsorption (0.53 mg/mL) was obtained by imidazole bearing adsorbent with the highest amount of imidazole and Among the adsorbents with synthesized linkers, the adsorbent with 1,2-ethanediol diglycidyl ether showed better performance and was able to purify 0.25 mg/mL IgG with high purity. The obtained pseudo-affinity adsorbents purify immunoglobulin G in one-step process with high purity and efficiency.