Magnetic Particle Spectroscopy (MPS) is a new measurement method related to Magnetic Particle Imaging (MPI). In MPS a sinusoidal signal is applied to the sample. Due to the non-linearity of the magnetization curve of the sample, the acquired signal contains higher harmonics. The magnetic characteristics of the sample can be calculated by this information. Hence MPS has become a standard method for characterizing and optimizing magnetic particles that are used either for MPI or Magnetic Resonance Imaging (MRI).

Our MPS software can perform simple "one-button" experiments as well as highly advanced measurements. Experienced users can access and change all parameters individually. Besides the automatic report generation for each measurement it is possible to access the acquired raw data.

The Polymer Profiler is a joint development of Pure Devices and the Fraunhofer Institute for Integrated Circuits IIS.

Polymers, such as plastics, adhesives and sealants as well as other magnetic resonance visible materials, can be analyzed and characterized non-destructively by the Fraunhofer EZRT Polymer-Profiler Software. The use of a the Pure Devices MRI system ensures an outstanding sensitivity for this task.

The data is acquired using magnetic fields and pulsed radio frequency (RF). It is then processed and displayed as plots by the software. Any material change caused by either chemical, thermal or aging processes has an influence on the MR data, enabling the user to detect this change and take prompt measures to assure the required quality or to regulate underlying processes.

Magnetic Particle Imaging (MPI) is a novel tomographic method for determining the distribution of magnetic material in three dimensions. Similar to Magnetic Particle Spectroscopy (MPS), MPI is based on the nonlinear magnetization response of magnetic iron oxide nanoparticles (MNP) to dynamic magnetic fields. Additional strong magnetic field gradients are used to encode the field of view (FOV) by selectively generating higher harmonics near the encoding scheme. The encoding scheme can have different shapes, such as field-free point (FFP) or field-free line (FFL), which can be moved through the FOV in a variety of ways (trajectories) [1,2,3].

Similar to PET or SPECT, MPI is a tracer-based method, which comes with a lot advantages, such as high spatial resolution [4], high sensitivity [5] and high temporal resolution [6]. These features build a promising new technology for different fields, such as material science, biology, chemistry, and medicine. Especially the latter field shows some interesting developments in the last decade, e.g., MPI as a promising tool for future intervention, such as PTA or stenting [7-12], but also novel scanner designs for human-sized applications [13-17].
Based on one novel scanner design, the pdMPI scanner is based on the traveling wave (TW) approach, which uses a dynamic linear gradient array for the generation of the strong magnetic field gradient required for the spatial encoding [18, 19]. With this TWMPI technique, several unique features, such as real parallel MPI [20], superspeed MPI [21], zoom-MPI [22], or hybrid imaging with CT [15, 23] or MRI [24, 25] are connected. This provides new possibilities and new applications for MPI.
A further development of the encoding scheme allows for the first time a fully electrical controlled 3D movement of an FFL [26] in combination with a small and lightweight hardware design [15].

The pdMPI device

Based on the TW-FFL technology, the pdMPI device provides the first benchtop 3D MPI scanner for research and education and gives an easy entry into the interesting field of MPI.
The pdMPI scanner is a highly flexible system, which comes with a fully 3D simulation framework [27], which not only allows a full emulation of the scanner but also image reconstruction and visualization (2d & 3D) in real-time [28, 29].
With the openMatlab interface, the pdMPI scanner can be easily adapted and integrated into established processes in industry, research, and education.
In the following, only few examples of FFL trajectories covering the data within the FOV of the scanner are shown. Until now, 10 different standard sequences are implemented but with the arbitrary adjustable frequencies, the pdMPI scanner can be set up for your application.

References

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[22]     P. Vogel, et al., Adjustable hardware lens for Traveling Wave MPI, IEEE Trans Magn, vol. 56(11):5300506, 2020.

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