New open access publication

Abstract

Magnetic nanoparticles can be used for a variety of medical applications. Magnetic hyperthermia, i.e. the heating of tumours by injected magnetic nanoparticles activated by an external alternating magnetic field, is a promising method for improving tumour therapy. If magnetic nanoparticles are to be used outside of patients, for example as markers on rapid test strips, particles of other materials and with more hard magnetic properties can be used. The synthesis of such hard magnetic nanoparticles from cobalt ferrite was systematically studied in the paper to investigate the effect of synthesis parameters such as temperature, duration, atmospheric oxygen content, and cobalt content on the resulting particle properties. The particles were extensively characterized by X-ray diffraction, magnetometry measurements, Mössbauer spectroscopy, and transmission electron microscopy. Limiting values for the synthesis conditions could be identified, which prevent the formation of parasitic phases in the particles, thus ensuring ideal magnetic behaviour. It was also shown that the coercivity of the particles, on which the achievable heating power depends to a large extent, exhibits a maximum at cobalt concentrations of 80 to 90% and decreases again for fully substituted cobalt ferrite (100%). The nanoparticles exhibit heating powers of up to 480 W/g and are thus promising for extracorporeal heating applications.

Zahn, D.; Landers, J.; Diegel, M.; Salamon, S.; Stihl, A.; Schacher, F.H.; Wende, H.; Dellith, J.; Dutz, S. :
Optimization of Magnetic Cobalt Ferrite Nanoparticles for Magnetic Heating Applications in Biomedical Technology.
Nanomaterials 2023, 13, 1673.

https://doi.org/10.3390/nano13101673
 

Contact:       Prof. Dr.-Ing. Silvio Dutz
                     M.Sc. Diana Zahn