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Abstract: Abstract Magnetic particle spectrometry (MPS) is an excellent and straightforward method to determine the response of magnetic nanoparticles to an oscillatingmagnetic field. Such fields are applied in magnetic particle imaging (MPI). However,state of the art MPS devices lack the ability to excite particles in multidimensional fieldsequences that are present in MPI devices. Especially the particle behavior caused byLissajous sequences cannot be measured with only one excitation direction. This workpresents a new kind of MPS which features two excitation directions to overcome thislimitation. Both field coils can drive AC as well as DC currents and are thereby ableto emulate the field sequences for arbitrary spatial positions inside an MPI device.Since the DC currents can be switched very fast, the device can be used as systemcalibration unit and acquire system matrices in very short time. These are crucialfor MPI image reconstruction. As the signal-to-noise-ratio provided by the MPS isapproximately 1000 times higher than that of actual imaging devices, the time spaceanalysis of particle signals is more precise and easier done. Four system matrices arepresented in this paper which have been measured with the realized multidimensionalMPS. Additionally, a time space comparison of the particle signal for Lissajous, radialand spiral trajectories is given.

[www] [BibTex]

Note: article

Abstract: Abstract Magnetic particle spectrometry (MPS) is an excellent and straightforward method to determine the response of magnetic nanoparticles to an oscillatingmagnetic field. Such fields are applied in magnetic particle imaging (MPI). However,state of the art MPS devices lack the ability to excite particles in multidimensional fieldsequences that are present in MPI devices. Especially the particle behavior caused byLissajous sequences cannot be measured with only one excitation direction. This workpresents a new kind of MPS which features two excitation directions to overcome thislimitation. Both field coils can drive AC as well as DC currents and are thereby ableto emulate the field sequences for arbitrary spatial positions inside an MPI device.Since the DC currents can be switched very fast, the device can be used as systemcalibration unit and acquire system matrices in very short time. These are crucialfor MPI image reconstruction. As the signal-to-noise-ratio provided by the MPS isapproximately 1000 times higher than that of actual imaging devices, the time spaceanalysis of particle signals is more precise and easier done. Four system matrices arepresented in this paper which have been measured with the realized multidimensionalMPS. Additionally, a time space comparison of the particle signal for Lissajous, radialand spiral trajectories is given.