Characterization of magnetic nanoparticles for narrow-band magnetic particle imaging

Magnetic particle imaging (MPI) is a promising imaging modality. Most MPI approaches are based on a wide-band detection, whereas our recently proposed narrow-band MPI (nbMPI) system only uses the  harmonic. In this contribution we present our investigation of different multicore magnetic nanoparticle (MNP) systems regarding their suitability as tracers for our nbMPI system. In contrast to wideband MPI where many harmonics of sufficient amplitude are required, in our nbMPI approach a high amplitude of the 3rd harmonic is essential. In addition to MPI measurements with complex phantoms, our investigation included the measurement of the static magnetization curve with a magnetic property measurement system MPMS3, of the complex ac susceptibility and the harmonic spectra with MPS. Of the studied MNP systems, perimag® and synomag®-D-70 from micromod GmbH provided the best performance. Both MNP systems have a comparably high saturation magnetization and sufficiently low relaxation times providing a good nbMPI imaging performance