One-pot synthesis of magnetic nanoparticles functionalized by green coatings

In the presented work, a new original procedure for the interfacial synthesis of the magnetic nanoparticles (MNPs) modified with a polymer shell and functionalized by an ionic liquid or a deep eutectic solvent in aqueous biphasic systems (ABSs) is proposed. The synthesis is carried out at the interface of immiscible liquids based on aqueous solutions of polyethylene glycol and inorganic salts. The advantages of the ABSs are biocompatibility, availability, and the high solvating properties of the components, which leads to control the composition and size of the prepared MNPs. The synthesis of the Fe₃O₄@PEG, Fe₃O₄@PEG@Cyphos IL 101, and Fe₃O₄@PEG@TOPO/butanol MNPs has been provided for biomedical and analytical applications. The morphology and structure of MNPs have been characterized by scanning and transmission electron microscopy, thermogravimetry, X-ray diffraction, and FT-IR spectroscopy. The average diameter of the MNPs is 12–14 nm with a narrow size distribution. Their superparamagnetic nature has been described using magnetometry. The synthesis parameters have been optimized and statistically analyzed using response surface methodology. The developed approach of interfacial synthesis can be potentially scaled up and/or be used to obtain nanoparticles of various composition and application.