Construction of ionic liquid-crosslinked magnetic surface-imprinted polymers for selective recognition of lysozyme

Abstract

A novel ionic liquid-crosslinked molecularly imprinted polymer with magnetic responsivity (IL-Fe3O4@AAm-MIP) is fabricated for the efficient and selective adsorption of lysozyme (Lys) via surface imprinting method by using Fe3O4 nanoparticles as carrier, acrylamide (AAm) as functional monomer, 1-(α-allyl acetate)-3-vinyl imidazole chloride ionic liquid as cross-linker and Lys as template molecule. The structures, morphologies and adsorption behaviors of IL-Fe3O4@AAm-MIP are investigated in detail. Compared with the non-imprinted polymer, the experimental results turn out that IL-Fe3O4@AAm-MIP exhibits a higher adsorption capacity of 334.1 mg/g with an imprinting factor (IF) of 2.94 owing to the imprinting effect. Simultaneously, the selective adsorption experiments are carried out and the IF obtained for the reference proteins, including bovine hemoglobin, bovine serum albumin, cytochrome C and ovalbumin, were 1.74, 0.19, 2.49 and 0.87, respectively, demonstrating the favorable selectivity of the IL-Fe3O4@AAm-MIP towards Lys. Besides, the IL-Fe3O4@AAm-MIP is proved to be able to specifically capture Lys from binary protein mixtures as well as actual biological sample. The obtained results revel that the developed IL-Fe3O4@AAm-MIP with rapid magnetic separation, high affinity and favorable selectivity is a promising material in the enrichment of biomacromolecules.