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In recent works, arbitrary waveform or pulsed excitation in Magnetic Particle Imaging (MPI) was proposed to offer better resolution and sensitivity. Generating these excitation fields poses a new challenge in MPI hardware design. This work proposes a method which models the excitation chain as a linear system and predicts the required input voltage for the desired output field. The initial prediction is then iteratively improved to compensate for inaccuracies of the model. The method is demonstrated to achieve accurate field waveforms in both linear and slew rate limited regions of the amplifier., International Journal on Magnetic Particle Imaging IJMPI, Vol 9 No 1 Suppl 1 (2023)

Magnetic particle imaging (MPI) is a pre-clinical imaging modality, whose system design is still evolving, in particular towards human studies and clinical use. Therefore, many MPI scanners are custom-made distributed systems, both on the hard- and the software side. In this work we present the open-source Julia framework MPIMeasurements.jl, which implements a composable representation of imaging systems. It also offers flexible data structures that allow the implementation of specific imaging protocols, such as online/offline measurements, repeated measurements and system matrix calibrations. %that are reusable across systems. The project is designed to be expanded to new systems through community development and component reuse. To showcase the versatility of the software package, we give an overview of four very different MPI systems, which were realized with MPIMeasurements.jl., International Journal on Magnetic Particle Imaging IJMPI, Vol 9 No 1 Suppl 1 (2023)

To transport drugs within the brain to their desired application site it is necessary to overcome the blood brain barrier (BBB). To protect the brain from the penetration of harmful substances, the BBB forms an endogenous protection. Different approaches exist to overcome the BBB. One possible approach are magnetic nanoparticles which can be used to move drugs through the blood-brain barrier using magnetic guidance. The system described here consists of three rings of permanent magnets in Halbach configuration with an inner diameter of 5.5 cm, which generate a high gradient of 5.8 T/m at the center, which can be used to study and optimize magnetic transport systems on cell models of a BBB., International Journal on Magnetic Particle Imaging, Vol 8 No 1 Suppl 1 (2022)

Magnetic particle imaging (MPI) systems do not only allow for the visualization of the distribution of magnetic nanoparticles, but the magnetic fields of an MPI scanner can be also used to apply a magnetic force or a torque. This enables the actuation of magnetic particles. Here, we demonstrate that magnetic microspheres (MMS) are well suitable candidates for the actuation and visualization with MPI. By means of magnetic particle spectrometer (MPS) measurements, a promising imaging performance of the MMS for MPI was confirmed. We show that MMS can be actuated by rotating focus fields of a preclinical MPI scanner. Since the used MMS can carry therapeutics, which can be released by means of hyperthermia, this approach paves the way towards an MPI monitored targeted drug delivery., International Journal on Magnetic Particle Imaging, Vol 8 No 1 Suppl 1 (2022)

The remote magnetic actuation of untethered devices has great potential for many clinical applications such as drug targeting and precision surgery. 3D printing offers great flexibility in the manufacturing process of these milli- and micro-scale devices. To achieve better functionalization of these devices it is beneficial to directly integrate the desired properties into the printing process. This work focuses on the development and analysis of a magnetic print material. NdFeB microparticles of different concentrations were incorporated into a liquid polymer resin for LCD-based 3D printing. The print quality is investigated and the resulting magnetic properties are analyzed for their suitability to be used for remote magnetic actuation., Transactions on Additive Manufacturing Meets Medicine, Vol 3 No 1 (2021): Trans. AMMM