The Applications of Magnetic Particle Imaging: From Cell to Body

Abstract

Magnetic particle imaging (MPI) is a cutting-edge imaging technique that is attracting increasing attention. This novel technique collects signals from superparamagnetic nanoparticles as its imaging tracer. It has characteristics such as linear quantitativity, positive contrast, unlimited penetration, no radiation, and no background signal from surrounding tissue. These characteristics enable various medical applications. In this paper, we first introduce the development and imaging principles of MPI. Then, we discuss the current major applications of MPI by dividing them into four categories: cell tracking, blood pool imaging, tumor imaging, and visualized magnetic hyperthermia. Even though research on MPI is still in its infancy, we hope this discussion will promote interest in the applications of MPI and encourage the design of tracers tailored for MPI.

Rapid Magneto-Sonoporation of Adipose-Derived Cells

“…Biocompatible nanoscale materials have introduced outstanding innovation in biomedicine, finding use in the controlled delivery of biomolecules, manipulation of cell phenotype and behavior, and improvement of structural or biological features of substrates used for cell growth [50][51][52]. Key biological applications include non-invasive imaging and drug delivery in living organisms, as well as tissue engineering and wound healing [52][53][54][55][56][57][58]. In many instances, the nanomaterial internalization within cells is a mandatory step that can be achieved via various routes.…”

Imaging‐Guided Cancer Therapy Based on Multifunctional Magnetic Nanoparticles†

“…Moreover, innovative imaging techniques have been developed, such as magnetic particle imaging (MPI), which is based on the nonlinear magnetization of superparamagnetic MNPs immersed in an alternating external magnetic field. [ 6 ] Besides, MNPs possess unique physicochemical properties that offer tremendous therapeutic potential, making image‐ guided cancer therapy possible. For instance, certain MNPs with strong absorption and high photothermal conversion efficiency (PCE) in the near‐infrared region can act as the potential photothermal therapy (PTT) agents.…”

Magnetic Nanoparticle Imaging: Insight on the Effects of Magnetic Interactions and Hysteresis of Tracers

“…Magnetic particle imaging (MPI) has emerged as a novel tomographic technique − with widespread prospective applications in biomedicine, − both as a standalone method of diagnostic imaging − and as an auxiliary diagnostic tool associated with specific therapies of precision medicine. − …”

“…MPI is based upon the detection and analysis of the voltage induced by magnetic tracers at the nanoscale (usually based on iron oxide nanoparticles as already approved by the U.S. Food and Drug Administration (FDA) for human use) under the combined action of a high-frequency sinusoidal magnetic field H ( t ) and of a nonuniform magnetic field characterized by a high gradient (called bias field). ,,, The technique has the double advantage of not requiring the use of ionizing radiation and of penetrating tissues deep inside a living body , (such a property being shared with the related technique of magnetic particle spectroscopy , ). MPI takes further advantage from the present-day knowledge on diffusion, steering, positioning, and clearance of magnetic nanoparticles inoculated in a living body. − …”