Magnetic Nanoparticles for Magnetic Resonance Imaging and Hyperthermia Applications

Abstract

Medicine provides an increasing interest for magnetic nanoparticles, thanks not only to the growing control of their chemical and morphological design and colloidal stabilization, but also to the increasing tendency to use magnetic fields in diverse medical areas such as radiology, neurosurgery, or oncology. This contribution focuses on their potential usefulness as contrast agents for magnetic resonance imaging (MRI) and colloidal mediators for magnetic fluid hyperthermia (MFH). A physical background of these nanoparticles magnetism is first considered discussing their behavior either under static magnetic field or an alternating one. The design and preparation of magnetic fluids is then described from the synthesis of nanoparticles up to their colloidal stabilization in physiological media. Requirements with regard to in vivo administration are subsequently presented, i.e., the factors affecting their biocompatibility, their biodistribution, the solutions envisaged for enhancing their half-life in the blood compartment, and the active targeting of tumor cells. Finally, magnetic nanoparticles are considered as contrast agents for MRI and mediators for MFH, highlighting the involved problems and the current and future possibilities for solving them.