Harmonic response of Gd-doped Mn-ferrite nanoparticles under AC magnetic field and optimization of Gd doping for MPI applications

Abstract

This study synthesized Gd-doped Mn-ferrite nanoparticles for magnetic particle imaging (MPI) applications with doping levels (x) of 0, 0.05, 0.07, and 0.10. Analyses using X-ray diffraction measurements unequivocally confirmed the presence of a spinel-type crystal structure in the synthesized particles and X-ray absorption fine-structure spectroscopy confirmed the incorporation of Gd atoms in place of Mn within the crystal lattice. Magnetization and harmonic measurements under an AC magnetic field revealed that particles with a high initial permeability and low coercivity showed a high response intensity. Notably, particles possessing a Gd doping level of x = 0.07 displayed the highest response and were considered promising as MPI materials.