Magnetic Characterization of Clustered Core Magnetic Nanoparticles for MPI

Diagnostic imaging is of utmost importance for clinical routine and research and is also gaining more and more relevance in preclinical research. Magnetic particle imaging (MPI) as a new imaging modality may open new perspectives in the field. Iron oxide magnetic nanoparticles (MNPs) are already used as MRI contrast agents are of general interest for various other biomedical applications, and are also promising as MPI tracers. However, to provide the desired performance for MPI, it is still necessary to optimize the particles signal efficacy. Optimization remains an unexpected challenge and, as a consequence, considerable importance is being given to the research of MNPs, where efforts have been placed to understand the relation between particle structure and particle magnetic properties in more detail. In the present study, two clustered core MNPs exhibiting similar structures, but significant differences in their magnetic particle spectra, are investigated. Their static and dynamic magnetic properties are analyzed to understand the reasons for such differences as well as to gain a better insight of their relation to the particle structure.