Linear structures of magnetic nanoparticles in hyperthermia and magnetic particle imaging

Abstract

The development of theranostic devices combining magnetic particle imaging (MPI) and magnetic hyperthermia opens new possibilities for clinical applications of magnetic nanoparticles (MNP), e.g., hyperthermia-mediated drug delivery. Enhancing MNP performance for such applications can be achieved by using linear structures of MNP (i.e. chains, elongated clusters) instead of randomly distributed MNP. Here, we investigate the hyperthermia and MPI performance of two types of MNP linear structures: one generated by exposing MNP to a static magnetic field inside a hydrogel and the other by extruding a mixture of polypropylene and MNP to hybrid fibers. For both types of linear structures, an increase in heating efficiency and MPI signal was observed when the linear structure orientation is in the direction of the excitation field. In summary, the generation of MNP linear structures is a promising approach to increase their performance in MPI and magnetic hyperthermia. For MPI image reconstruction, the orientation of the linear structures relative to the drive field direction should be considered.