Fabrication and evaluation of protein imprinted polymer based on magnetic halloysite nanotubes

Abstract

A novel protein imprinted polymer, which combined the surface imprinting technology and magnetic halloysite nanotubes (MHNTs), was prepared for selective separation of a template protein. In this work, MHNTs were synthesized through the coprecipitation method based on encapsulation of Fe₃O₄ nanoparticles in halloysite nanotubes. The surface of the MHNTs was modified with vinyl groups through reaction with 3-(methacryloyloxy)propyl trimethoxysilane. Subsequently, the modified MHNTs were used as a support, N-isopropylacrylamide and methacrylic acid as bifunctional monomers, N,N′-methylene bisacrylamide as the crosslinking agent, and ammonium persulphate and N,N,N′,N′-tetramethylethylenediamine as initiators. The resulting polymer was named MHNTs@BSA-MIP, which was characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and vibrating sample magnetometry. The MHNTs@BSA-MIP exhibited high adsorption (48.4 mg g⁻¹), good selectivity, rapid kinetic binding (45 min), fast magnetic separation (10 s), and favorable reproducibility (relative standard deviation <8% for batch-to-batch evaluation). The prepared MHNTs@BSA-MIP is suitable for separation and provides a significant reference for other proteins in proteomics.