Measurement of the nonmagnetic coating thickness of core-shell magnetic nanoparticles by controlled magnetization magnetic force microscopy

摘要

Magnetic nanoparticles (MNPs) represent an interesting tool for several biomedical applications. In order to\udimprove the dispersion stability, the biocompatibility and bio-functionality, MNPs need to be coated with non-magnetic\udfilms. The optimization of these systems requires the deep characterization not only of the magnetic core, but also of the\udcoating features. Beside the chemical and physical properties of the coating, its thickness is another important property\udwhich can influence the size, the shape and the overall magnetic behavior of the NPs system. In this work we propose a\udpossible method to measure the thickness of the non-magnetic coating of core-shell MNPs through the use of controlled\udmagnetization-magnetic force microscopy (CM-MFM). A preliminary study on the applicability of the proposed method\udhas been performed on Fe3O4 NPs coated with a Cu film.