Speaker
Description
Superparamagnetic iron oxide nanoparticles (SPIONs), particularly Fe$_3$O$_4$, are among the most extensively studied magnetic nanoparticles (MNPs) due to their high biocompatibility and biodegradability, making them highly suitable for biomedical applications such as magnetic resonance imaging (MRI). While SPIONs have demonstrated promising heating capabilities in magnetic hyperthermia, particularly in prostate cancer therapy, their magnetic response under specific conditions—such as varying distances from an external magnetic field, concentration in tumor tissue, and stability in physiological environments—may not always be optimal [1]. To enhance their performance and adapt them to specific biomedical applications, various modification strategies have been explored.
One of the most effective modification approaches involves altering the chemical composition through cation substitution. Partial replacement of Fe atoms with elements such as Mn, Co, or Ni leads to the formation of spinel ferrites with tunable physicochemical properties. By adjusting the cation distribution within the spinel sublattices, the magnetic characteristics of these nanosystems can be fine-tuned through super-exchange interactions. In addition to compositional modifications, strategies such as controlling nanoparticle shape, size, and surface properties further enhance their magnetic performance. These modifications significantly affect key magnetic parameters, particularly anisotropy and coercivity, which are crucial for improving hyperthermia efficiency.
CoFe$_2$O$_4$ nanocubes in three different size modifications ($10$, $13$, and $17$ nm) were prepared by thermal decomposition and investigated to analyze the impact of size variation on their magnetic properties. SQUID magnetometry was used to examine the magnetic properties of the systems by measuring $M$(H) and $M$(T) curves in both Zero-Field Cooling (ZFC) and Field Cooling (FC) regime. The collected data were then analyzed using appropriate models to investigate the overall magnetic behavior of the systems. From this analysis, values for anisotropy, coercivity, and saturation magnetization were extracted. The results were evaluated for the potential use of these nanoparticles in magnetic hyperthermia. In addition to magnetic properties, the structure of the MNPs was examined using TEM/SEM microscopy, and XRD analysis. Based on the obtained results, these systems show promising potential for application in magnetic hyperthermia.
Acknowledgements
Funded by the EU NextGenerationEU through the Recovery and Resilience Plan for Slovakia under the project No. 09I03-03-V04-00177 and supported by the Slovak Research Agency under the contracts: APVV-20-0512 and VEGA1/047/25.
References
[1] C. Caizer, “Magnetic/Superparamagnetic Hyperthermia as an Effective Noninvasive Alternative Method for Therapy of Malignant Tumors,” Nanotheranostics. Springer International Publishing, pp. 297–335, 2019. https://doi.org/10.1007/978-3-030-29768-8_14
