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bioRxiv · 10.1101/2024.12.04.626925

Magnetically induced magnetosome chain (MAGiC):A biogenic magnetic-particle-imaging tracer with high performance and navigability

Li, L.·Zhao, C.·Zhao, Z.·Han, D.·Liao, Y.·Liu, Y.·Liu, S.·Jia, X.·Tian, J.·Liu, Q.·Feng, X.
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Abstract

Magnetic particle imaging (MPI) enables real-time, sensitive and quantitative visualization of magnetic tracers spatial distribution, augmenting the capability of in vivo imaging technologies. Previous tracer studies in MPI have primarily focused on superparamagnetic nanoparticles; however, their non-ideal sigmoidal magnetization response limits the spatial resolution. Here we demonstrate the utilization of magnetically induced magnetosome chain (MAGiC) as a novel superferromagnetic MPI tracer, exhibiting a 25-fold improvement in resolution and a 91-fold enhancement in signal intensity compared to the commercial tracer VivoTrax+. The spatial resolution of MPI was pushed to an unprecedented 80 m under a 4 T/m gradient field. Additionally, MAGiC can be precisely controlled using magnetic fields, enabling it to function as a MPI trackable microrobot. We provided a theoretical model elucidating MAGiCs unique properties, and validated its imaging and actuation performance through phantom studies and in vivo experiments. As a high-performance MPI tracer and magnetic microrobot with exceptional capabilities, MAGiC holds tremendous potential for diverse applications including cell tracking, targeted drug delivery as well as therapeutic interventions.

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Li, L., Zhao, C., Zhao, Z., Han, D., Liao, Y., Liu, Y., Liu, S., Jia, X., Tian, J., Liu, Q., Feng, X.. 2024-12-09. Magnetically induced magnetosome chain (MAGiC):A biogenic magnetic-particle-imaging tracer with high performance and navigability. https://doi.org/10.1101/2024.12.04.626925

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