$\mu $ MPI—Initial Experiments With an Ultrahigh Resolution MPI

Magnetic particle imaging (MPI) is a novel imaging method for the depiction of superparamagnetic materials. Since the first publication several MPI scanner were presented, which work at gradient strength of ~2-7 T/m. This is reasonable for in vivo imaging and provides a resolution of ~1 mm. In this paper, several approaches for a micro-MPI (μMPI) device for very small samples are presented, which works at a very high magnetic gradient strength of ~85 T/m. This results in a theoretical resolution <;100 μm. This μMPI device can be operated at several modes, which have different advantages. In preliminary tests, the feasibility of the μMPI device has been proven.