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

A novel ionic liquid-crosslinked molecularly imprinted polymer with magnetic responsivity (IL-Fe 3 O 4 @AAm-MIP) is fabricated for the efficient and selective adsorption of lysozyme (Lys) via surface imprinting method by using Fe 3 O 4 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-Fe 3 O 4 @AAm-MIP are investigated in detail. Compared with the non-imprinted polymer, the experimental results turn out that IL-Fe 3 O 4 @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-Fe 3 O 4 @AAm-MIP towards Lys. Besides, the IL-Fe 3 O 4 @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-Fe 3 O 4 @AAm-MIP with rapid magnetic separation, high affinity and favorable selectivity is a promising material in the enrichment of biomacromolecules.