Protein imprinted ionic liquid polymer on the surface of multiwall carbon nanotubes with high binding capacity for lysozyme

Abstract

In this research, ionic liquid as functional monomer to prepare molecularly imprinted polymers for protein recognition was for the first time demonstrated, in which, 1-vinyl-3-butylimidazolium chloride was selected as functional monomer, acrylamide as co-functional monomer and lysozyme (Lyz) as template protein to synthesize imprinted polymers on the surface of multiwall carbon nanotubes in aqueous medium. The results indicated that ionic liquid was helpful to improve binding capacity of imprinted polymers, which had a maximum binding capacity of 763.36 mg/g in the optimum adsorption conditions. The prepared imprinted polymers had a fast adsorption rate and a much higher adsorption capacity than the corresponding non-imprinted polymers, with the difference in adsorption capacity up to 258.31 mg/g. The obtained polymer was evaluated by Lyz, bovine serum albumin (BSA), bovine hemoglobin (BHb), equine myoglobin (MB) and cytochrome c (Cyt c). The selectivity factor (β) for Lyz/BSA, Lyz/Mb, Lyz/BHb, and Lyz/Cyt c were 7.17, 2.12, 1.76 and 1.57, respectively, indicating the imprinted polymers had a good selectivity. Easy preparation of the imprinted polymers as well as high ability and selectivity to adsorb template proteins makes this polymer attractive and broadly applicable in biomacromolecular separation, biotechnology and sensors.

Keywords: Ionic liquids; Lysozyme; Molecularly imprinted polymers; Multiwall carbon nanotubes; Protein recognition.