Magnetic particle imaging: tracer development and the biomedical applications of a radiation-free, sensitive, and quantitative imaging modality

Abstract

Magnetic particle imaging (MPI) is an emerging tracer-based modality that enables real-time three-dimensional imaging of the non-linear magnetisation produced by superparamagnetic iron oxide nanoparticles (SPIONs), in the presence of an...

Ferrofluids and bio-ferrofluids: looking back and stepping forward

“…The same conclusion was reached in a most recent review on SPION synthesis for magnetic particle imaging. 96 Although the authors emphasized that the details of SPION synthesis do not fall within the scope of the review, they summarized it very concisely and purposefully, comparing the five well-established synthesis methods (co-precipitation, thermal decomposition, hydrothermal, microemulsion and sol–gel), and describing the mostly beneficial properties of co-precipitation and thermal decomposition. Namely, co-precipitation is a cost-effective, simple, scalable, environmentally friendly method with high-yielding, but polydisperse products with a low degree of crystallinity.…”

Applications of Magnetic Particle Imaging in Biomedicine: Advancements and Prospects

“…That is, the Brownian rotation describes the physical rotation of the entire particles, and the Néel rotation describes the internal flip of SPIONs' magnetic moment for a fixed particle. Brownian and Néel relaxation rotations coexist and occur on timescales of microseconds and nanoseconds, respectively (Harvell-Smith et al, 2022).…”

“…On the basis of the magnetic properties of particles used for imaging, an MPI scanner has three major hardware components: a time-varying homogeneous magnetic field (drive field), a strong magnetic gradient field (selective field), and a receiving coil (Du et al, 2013;Harvell-Smith et al, 2022). The drive field is originally…”

“…The symmetry of the scanner produces a magnetic field gradient with an FFP located at the center (Gleich et al, 2005). Currently, a system is permitted to have a gradient of 7 T/m in preclinical application (Yu et al, 2017;Harvell-Smith et al, 2022). The receiver coils record signals of SPIONs through inducing voltages that linearly relate to the density of particles at the instantaneous position of the FFP (Saritas et al, 2013).…”

“…The receiver coils record signals of SPIONs through inducing voltages that linearly relate to the density of particles at the instantaneous position of the FFP (Saritas et al, 2013). Furthermore, the motion and rotation of the system should overlay the selective field to cover an area or volume given by a defined field of view (FOV) (Knopp et al, 2017;Chandrasekharan et al, 2018;Tay et al, 2021;Harvell-Smith et al, 2022). Additionally, unlike MRI, MPI involves the simultaneous transmission and receiving of signals.…”