2024-04-12

Ethylene Vinyl Alcohol Copolymer Nanoffbrous CationExchange Chromatographic Membranes with a Gradient PorousStructure for Lysozyme Separation

Lysozyme, a common antimicrobial agent, is widely used in the food, biopharmaceutical,chemical, and medicine ffelds. Rapid and effective isolation of lysozymes is an everlasting topic. Inthis work, ethylene vinyl alcohol (EVOH) copolymer nanoffbrous membranes with a gradient porousstructure used for lysozyme adsorption were prepared through layer-by-layer nanoffber wet-layingand a cost-efffcient ultraviolet

(UV)-assisted graft-modiffcation method, where benzophenone wasused as an initiator and 2-acrylamide-2-methylpropanesulfonic acid as a modifying monomer. Asindicated in the Fourier Transform Infrared

(FTIR) and X-ray photoelectric energy spectrometer(XPS) investigation, sulfonic acid groups were

introduced on the surface of the modiffed nanoffbrousmembrane, which possessed the ability to adsorb

lysozyme. Compared with membranes withhomogenous porous structures, membranes with a gradien

t porous structure present higher static(335 mg/g) and dynamic adsorption capacities (216.3 mg/g). Meanwhile, the adsorption capacityremained high after ffve cycles of the adsorption–desorption process. The results can be attributed tothe gradient porous structure rather than the highest porosity and speciffc surface area. This suggeststhat the membrane with comprehensive separation performance can be designed from the view ofthe transmembrane porous structure, which is of signiffcance for the development of next-generationadvanced chromatographic membranes.Keywords: benzophenone; 2-Acrylamido-2′

Ethylene Vinyl Alcohol Copolymer Nanoffbrous CationExchange Chromatographic Membranes with a Gradient PorousStructure for Lysozyme Separation