International Journal on Magnetic Particle Imaging IJMPI
Vol. 12 No. 1 Suppl 1 (2026): Int J Mag Part Imag
https://doi.org/10.18416/IJMPI.2026.2603015

Proceedings Articles, ID 940

Strong magnetic interaction potentially favors smaller particles in MPS

Main Article Content

Mohamad Bilal Abbas (Department of Medical Engineering and Applied Mathematics, FH Aachen University of Applied Sciences, Jülich, Germany), Merle Kott (Department of Medical Engineering and Applied Mathematics, FH Aachen University of Applied Sciences, Jülich, Germany), Hans-Joachim Krause (Institute of Biological Information Processing, Forschungszentrum Jülich, Jülich, Germany), Ulrich Engelmann (Department of Medical Engineering and Applied Mathematics, FH Aachen University of Applied Sciences, Jülich, Germany)

Abstract

Magnetic nanoparticles (MNPs) are pivotal in biomedical applications such as imaging, hyperthermia, and biosensing due to their distinct relaxation dynamics under alternating magnetic fields (AMF). In vivo, MNPs are gradually internalized into cellular and tissue environments, where decreasing interparticle distances – resulting from aggregation, target binding, and dense packing – alter their magnetic response to AMF. These changes amplify magnetic dipole particle-particle interactions (pp-IA) among MNP, notably impacting their relaxation behavior. In this work, we investigate the effect of pp-IA on magnetic particle spectroscopy (MPS) via stochastic simulations coupling Néel and Brownian relaxation mechanisms. Our preliminary results provide evidence that at average interparticle distances below ~50 nm, MNPs with smaller core size (16 nm) yield stronger MPS signals than larger cores (20–28 nm).

Article Details

References

[1] I. Slabu, et al., "Modeling of magnetoliposome uptake in human pancreatic tumor cells in vitro", Nanotechnology, vol. 30, no.18, p. 184004, 2019, doi: 10.1088/1361-6528/ab033e.

[2] H. Arami, A. Khandhar, D. Liggitt, and K. M. Krishnan, "In vivo delivery, pharmacokinetics, biodistribution and toxicity of iron oxide nanoparticles", Chemical Society reviews, vol. 44, no. 23, pp. 8576–8607, 2015, doi: 10.1039/c5cs00541h.

[3] M. B. Abbas, A. M. Pourshahidi, H.-J. Krause, and U. Engelmann, "How MNP respond to dual-frequency magnetic excitation in viscous media", International Journal on Magnetic Particle Imaging IJMPI, vol. 11, 2025, doi: 10.18416/IJMPI.2025.2503033.

[4] U. M. Engelmann, A. Shalaby, C. Shasha, K. M. Krishnan, and H.-J. Krause, "Comparative Modeling of Frequency Mixing Measurements of Magnetic Nanoparticles Using Micromagnetic Simulations and Langevin Theory," Nanomaterials, vol. 11, no. 5, 2021, doi: 10.3390/nano11051257.

[5] U. M. Engelmann, C. Shasha and I. Slabu, Magnetic Nanoparticle Relaxation in Biomedical Application, in Magnetic Nanoparticles in Human Health and Medicine: Current Medical Applications and Alternative Therapy of Cancer, 1st ed., C. Caizer, Ed. Hoboken, John Wiley & Sons, 2021, pp. 327–354, doi: 10.1002/9781119754725.ch15.

[6] H.-J. Krause and U. M. Engelmann, “Fundamentals and Applications of Dual-Frequency Magnetic Particle Spectroscopy: Review for Biomedicine and Materials Characterization”, Advanced Science, vol. 12, no. 13, pp. 2416838, 2025, doi: 10.1002/advs.202416838.

[7] S. L. Saville, et al., "The formation of linear aggregates in magnetic hyperthermia: Implications on specific absorption rate and magnetic anisotropy", Journal of colloid and interface science, vol. 424, p. 141-151, 2014, doi: 10.1016/j.jcis.2014.03.007.

Most read articles by the same author(s)