Magnetic Nanoparticle-Gel Materials for Development of MPI and MRI Phantoms

Abstract

To evaluate performance of commercial as well as various custom-made scanners in several laboratories, dedicated phantoms with defined magnetic nanoparticle (MNP) distributions are required. Pre-requirement for the development of such phantoms is the establishment of suitable MNP-matrix combinations. In this study, two different gel types were used as matrix materials, which show similar imaging behavior in MRI and MPI compared to body tissue: water based biopolymers and synthetic polymers. Aqueous suspensions of MNP coated with different types of functionalized dextranes were used for embedding particles into the biopolymers, and organic fluids with oleic acid coated MNP for synthetic polymers, respectively. The obtained MNP-matrix combinations were tested for their mechanical stability by means of mechanical load tests. The homogeneity of MNP distribution and immobilization within the matrix was determined by optical investigation of the samples with a microscope and by investigation of the magnetic particle properties measured by vibrating sample magnetometry. In summary, we found suitable combinations of coated magnetic nanoparticles and matrix materials for the buildup of MPI phantoms, which guarantee a fixation of the MNP within the matrix without agglomeration of the particles. Int. J. Mag. Part. Imag. 4(2), 2018, Article ID: 1811001, DOI: 10.18416/IJMPI.2018.1811001