Fabrication of macroporous microspheres with core-shell structure for negative chromatography purification of virus

•Macroporous polymer microspheres with core-shell structure was synthesized by ATRP.•The inert shell and active cored was designed through separately modification.•The pores of shell were 100–200 nm smaller than core of 500–900 nm.•The core-shell microspheres can purification of AIV in negative chromatography.•The core-shell microspheres can be used as matrix for different chromatographic modes. The macroporous microspheres with core-shell structure, based on a copolymer of 4-Vinylbenzyl chloride, glycidyl methacrylate, and ethylene glycol dimethacrylate, were fabricated through atom transfer radical polymerization suspension polymerization. The microspheres showed 100–200 nm pores in shell and 500–900 nm pores in core. The shell was hydrophilic modified through grafting of poly(N-hydroxyethyl acrylamide) onto the shell surface for reducing adsorption of proteins. The core was coupled with a ligand of poly(ethylene imine) that could bind the proteins. Feedstock of avian influenza virus could be purified on these modified microspheres through negative chromatography. Avian influenza virus cannot enter the core and was recovered from the flow-through, while other proteins with negative charges were able to penetrate into the core and bind to the poly(ethylene imine) ligands. The dynamic binding capacity of proteins was higher on this medium (61 mg/mL) than the commercially available resin (12 mg/mL, Capto Core 700).