Magnetic Particle Imaging: From Tracer Design to Biomedical Applications in Vasculature Abnormality

Abstract

Magnetic particle imaging (MPI) is an emerging non‐invasive tomographic technique based on the response of magnetic nanoparticles (MNPs) to oscillating drive fields at the center of a static magnetic gradient. In contrast with magnetic resonance imaging (MRI), which is driven by uniform magnetic fields and projects the anatomic information of the subjects, MPI directly tracks and quantifies MNPs in vivo without background signals. Moreover, it does not require radioactive tracers and has no limitations on imaging depth. This review first introduces the basic principles of MPI and important features of MNPs for advanced imaging sensitivity, spatial resolution, and targeted biodistribution. The latest research on optimized MPI tracers is reviewed based on their material composition, physical properties, and surface modifications. Since all the imaging benefits have led to a series of promising biomedical applications, we also discuss recent relational practices of MPI in vascular abnormalities, including cardiovascular and cerebrovascular systems, and cancers. Finally, some considerations of obstructions and recent progress closely related to the clinical translation of MPI are summarized to provide possible direction for future research and development.This article is protected by copyright. All rights reserved

Elucidating Iron Metabolism through Molecular Imaging

“…Further research indicates that by adjusting the surface modifications and functionalization of SPIOs to enhance their specificity and sensitivity in MPI imaging, their affinity for specific cancer cell types can be increased. Additionally, combining drug carriers or therapeutic agents with SPIOs promises the integration of imaging and therapy, further expanding the application scope of MPI technology in cancer diagnosis and treatment [98]. The gastrointestinal tract, the primary site for iron absorption in the human body, is crucial in maintaining iron metabolic balance.…”

Magnetic Nanomaterials for Hyperthermia-Based Therapy, Imaging, and Drug Delivery

“…Their first medical applications were related to their role in changing water proton magnetic relaxation times, being used as contrast agents in magnetic resonance imaging (MRI) [ 2 ]; iron oxide MNPs are FDA-approved for imaging purposes and anemia treatments. While numerous studies are dedicated to improving the contrast in both T 1 and T 2 weighted MRI images using MNPs, magnetic particle imaging (MPI) has emerged in the last decade as an alternate technique, with tremendous potential in medical imaging [ 3 ], featuring multiple advantages such as linear quantitation, no tissue background, deep penetration, and no use of ionizing radiation.…”