Magnetic Particle Spectroscopy

The magnetic particle spectrometer (MPS) is used for characterizing magnetic nanoparticles. It exploits the nonlinear magnetization curve of super paramagnetic particles: By analyzing the harmonic response of the particles to a pure sine excitation field it is possible to determine their properties such as hydrodynamic size and magnetic moment.

This type of analysis is especially suited to characterize the imaging performance of particles when they are used in magnetic particle imaging (MPI). This is due to the fact that the MPS relies on the same effects that MPI uses for spatial encoding. Therefore the same particle properties are explored.

The institute has a MPS setup with a frequency range from 500 Hz to 10 kHz that is routinely used for particle characterization with flux densities up to 25 mT.
We are currently building another setup with an extended frequency range up 100kHz.


Figure: MPS setup