Preparation of Cu²⁺-mediated magnetic imprinted polymers for the selective sorption of bovine hemoglobin

In this work, a novel Cu²⁺-mediated core-shell bovine hemoglobin imprinted superparamagnetic polymers were synthesized. First, carboxyl group directly-functionalized Fe₃O₄ nanoparticles were produced by a facile one-pot hydrothermal method. Next, copper ions were introduced to chelate with carboxyl groups and further bonded with template bovine hemoglobin as co-functional monomer. Then, functional monomers 3-aminopropyltriethoxylsilane and octyltrimethoxysilane were adopted to form the thin polymer layers. Finally, after removal of the templates, the imprinting shells with specific recognition cavities for bovine hemoglobin were obtained on Fe₃O₄ nanoparticles. The resultant molecularly imprinted polymers have high adsorption capacity and satisfactory selectivity for bovine hemoglobin with the help of copper ions. The obtained magnetic nanomaterials were characterized by transmission electron microscopy, Fourier-transform infrared spectra, X-ray diffraction, and vibrating sample magnetometer. The measurements demonstrated that the as-synthesized nanomaterials exhibited good dispersion, high crystallinity, and satisfactory superparamagnetic properties. The feasibility of this method was further confirmed by using the imprinted nanomaterials to specifically extract bovine hemoglobin from real bovine blood samples.