Brush-like dextran-grafted affinity wood monolithic column: A novel efficiency, eco-friendly technology for antibody purification

Abstract

Wood, as a green, sustainable, natural material with a porous structure, is being explored as a backbone for new separation materials. However, wood has a high percentage of through pores and a small specific surface area, which reduces the adsorption capacity and efficiency. Here, we aimed to improve the separation effect by forming a brush-like graft layer on the wood surface through dextran graft modification. It was achieved by twice-modifying the wood with dextran and 3,3′-diaminodipropylamine, followed by further coupled with protein A to create a brush-like affinity monolithic column. The adsorption kinetics and static adsorption results showed that static adsorption capacity of affinity wood monolithic column was able to reach 47.15 mg/g and the adsorption equilibrium could be reached in 30 min. Meanwhile, the affinity wood monolithic column also possessed a dynamic theoretical adsorption capacity of 34.69 mg/g. Based on the results of IgG purification, it also showed excellent separation ability, and the IgG solution with purity of more than 95% could be obtained by one-step purification. Analysis of its adsorption behavior, the excellent separability was mainly made due to the unique structure of the wood and the modification of the dextran chains. This novel brush-like dextran-grafted affinity wood monolithic column provides an environmentally friendly, efficient and low-cost chromatographic matrix for the IgG separation.