International Journal on Magnetic Particle Imaging IJMPI
Vol. 5 No. 1-2 (2019): Int J Mag Part Imag

Research Articles

One-Dimensional Multi-Frequency Spectrometer

Main Article Content

Christian Knopke (Lodestone Biomedical LLC, Lebanon, Hanover, New Hampshire, USA), Bradley W Ficko (Lodestone Biomedical LLC, Lebanon, Hanover, New Hampshire, USA), Solomon G Diamond (Lodestone Biomedical LLC, Lebanon, Hanover, New Hampshire, USA Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, USA)


Magnetic Particle Spectroscopy (MPS) is an important measurement method to characterize the non-linear behavior of magnetic nanoparticles (MNPs). MPS systems provide valuable data for developing efficient magnetic particle imaging (MPI) methods and optimizing MNP contrast agents. We developed a multiple-excitation-coil spectrometer to recreate AC field patterns that are otherwise only found in 3D MPI systems. The presented Nanoparticle Characterization System (NCS) is capable of creating gradient fields and multi-frequency excitation fields as well as AC field-free-points. With its integrated sample mover, the NCS enables investigations into the effects of these field patterns on samples of > 0.1 µg iron mass in up to 100 µl volume along one dimension.


Int. J. Mag. Part. Imag. 5(1-2), 2019, Article ID: 1907002, DOI: 10.18416/IJMPI.2019.1907002

Article Details


[1] S. Biederer, T. Knopp, T. F. Sattel, K. Lüdtke-Buzug, B. Gleich, J. Weizenecker, J. Borgert, T. M. Buzug, and K. Lüdtke-Buzug. Magnetization response spectroscopy of superparamagnetic nanoparticles for magnetic particle imaging. Journal of Physics D: Applied Physics, 42(20):205007, 2009, doi:10.1088/0022-3727/42/20/205007.

[2] D. Schmidt, M. Graeser, A. von Gladiss, T. M. Buzug, and U. Steinhoff. Imaging Characterization of MPI Tracers Employing Offset Measurements in a two DimensionalMagnetic Particle Spectrometer. International Journal on Magnetic Particle Imaging, 1(2), 2016, doi:10.18416/IJMPI.2016.1604002.

[3] N. Löwa, M. Seidel, P. Radon, and F.Wiekhorst. Magnetic nanoparticles in different biological environments analyzed by magnetic particle spectroscopy. Journal ofMagnetism and Magnetic Materials, 427:133–138, 2017, doi:10.1016/j.jmmm.2016.10.096.

[4] C. Gräfe, I. Slabu, F. Wiekhorst, C. Bergemann, F. von Eggeling, A. Hochhaus, L. Trahms, and J. H. Clement. Magnetic particle spectroscopy allows precise quantification of nanoparticles after passage through human brain microvascular endothelial cells. Physics in Medicine and Biology, 61(11):3986–4000, 2016, doi:10.1088/0031-9155/61/11/3986.

[5] M. Shliomis. Effective viscosity of magnetic suspensions. Zhurnal Eksperimentalnoi i Teoreticheskoi Fiziki, 61:2411–2418, 1972.

[6] Néel. Théorie du traînage magnétique des ferromagnétiques en grains fins avec application aux terres cuites. Annales de Géophysique, 5:99–136, 1949.

[7] W. F. Brown. Thermal Fluctuations of a Single-Domain Particle. Physical Review, 130(5):1677–1686, 1963, doi:10.1103/PhysRev.130.1677.

[8] D. Eberbeck, C. Bergemann, F. Wiekhorst, U. Steinhoff, and L. Trahms. Quantification of specific bindings of biomolecules by magnetorelaxometry. Journal of Nanobiotechnology, 6(1):4, 2008, doi:10.1186/1477-3155-6-4.

[9] A. M. Rauwerdink and J. B.Weaver. Concurrent quantification of multiple nanoparticle bound states.Medical Physics, 38(3):1136–1140, 2011, doi:10.1118/1.3549762.

[10] N. Löwa, P. Radon, O. Kosch, and F. Wiekhorst. Concentration Dependent MPI Tracer Performance. International Journal on Magnetic Particle Imaging, 2(1), 2016, doi:10.18416/IJMPI.2016.1601001.