Molecularly imprinted polymer functionalized magnetic Fe3 O4 for the highly selective extraction of triclosan.

We present a facile strategy to prepare the molecularly imprinted polymers layer on the surface of Fe3 O4 nanoparticles with core-shell structure via sol-gel condensation for recognition and enrichment of triclosan. The Fe3 O4 nanoparticles were first synthesized by a solvothermal method. Then, template triclosan was self-assembled with the functional monomer 3-aminopropyltriethoxysilane on the silica-coated Fe3 O4 nanoparticles in the presence of ethanol and water. Finally, the molecularly imprinted polymers were formed on the surface of silica-coated Fe3 O4 nanoparticles to obtain the product. The morphology, magnetic susceptibility, adsorption, and recognition property of magnetic molecularly imprinted polymers were characterized using transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffractometry, vibrating sample magnetometry, and re-binding experiments. The magnetic molecularly imprinted polymers showed binding sites with good accessibility, fast adsorption rate, and high adsorption capacity (218.34 μg/g) to triclosan. The selectivity of magnetic molecularly imprinted polymers was evaluated by the rebinding capability of triclosan and two other structural analogues (phenol and p-chlorophenol) in a mixed solution and good selectivity with an imprinting factor of 2.46 was obtained. The application of triclosan removal in environmental samples was demonstrated.