Chapter 7 - Superparamagnetic iron oxide nanoparticles for theranostics

Abstract

Biomedical nanomagnetics is a mulitidisciplinary research area in nanoscience, engineering, and medicine with broad applications in imaging, diagnostics, and therapy. Recent developments offered exciting possibilities in personalized medicine. The integrated approaches combined with chemistry, materials science, physics, engineering, biology, and medicine had been implemented. Emphasizing this perspective, important issues were addressed for the rapid development of the field, that is, magnetic behavior at the nanoscale with emphasis on the relaxation dynamics, synthesis and surface functionalization of nanoparticles (NPs) and core–shell structures, biocompatibility and toxicity studies, biological constraints and opportunities, as well as in vivo and in vitro applications. Specifically, the targeted drug delivery and triggered release were mainly discussed. The novel contrast agents had widely applied in magnetic resonance imaging (MRI), in vitro diagnostics, and cancer therapy. The emerging magnetic nanoparticles (MNPs) imaging technique had performed enough capability and sensitivity compared with established imaging methods. In addition, the physics of self-assembly, which is fundamental to both biology and the future development of nanoscience, is illustrated in the area of MNPs. It is shown that various competing energies associated with self-assembly converge on the nanometer length scale and different assemblies can be tailored by varying particle size and size distribution. With the rapid development in nanotechnology, significant efforts have been made by multidisciplinary researchers, in an attempt to fabricate innovative nanomaterials to improve current diagnostic imaging techniques and treatment modalities for dreaded diseases. In particular, NPs for theranostic applications can basically be designed with an integrated capability, by incorporating both diagnostic and therapeutic components. Such a combination of multiple modalities within a single nanoplatform allows accurate diagnosis and effective therapy concurrently, largely reducing the occurrence of side effects. Among the various inorganic NPs, MNPs have exhibited distinctive physical properties and are capable of precise target imaging and drug release, inducing thermal therapy, as well as regulating cell signaling, making them ideal nanoplatform materials for theranostic applications. MNPs provide valuable platforms with potential exploitation in biomedicine. MNPs have been proposed as magnetic guidance in drug delivery and magnetic separation, as contrast agents in MRI, heat mediators in hyperthermia treatments or the mechanosensors of magnetic mechanical forces. In this chapter, we are comprehensively address these issues aiming to highlight the capability of the MNPs, especially superparamagnetic iron oxide nanoparticles.