Magnetic Nanoparticles and Their Applications in Medicine

Abstract

Magnetic nanoparticles have attracted attention in modern medicine and pharmacology owing to their potential usefulness as contrast agents for MRI, as colloidal mediators for cancer magnetic hyperthermia or as active constituents of drug-delivery platforms. This review examines these in vivo applications through an understanding of the involved problems and the current and future possibilities for resolving them. A special emphasis is placed upon magnetic nanoparticle requirements from a physical viewpoint (e.g., relaxivity for MRI, specific absorption rate for hyperthermia and magnetic guidance), the factors affecting their biodistribution after intravenous injection (e.g., size and surface hydrophobic/hydrophilic balance) and the solutions envisaged for enhancing their half-life in the blood compartment and in targeting tumor cells.

Chains of Magnetosomes Extracted from AMB-1 Magnetotactic Bacteria for Application in Alternative Magnetic Field Cancer Therapy

“…These nanoparticles may indeed potentially be guided within the cancer cells using a magnetic field, detected using MRI (magnetic resonance imaging) and heated by being exposed to an alternative magnetic field. In this case, the destruction or elimination of tumors would occur by increasing the tumor temperature typically within the range of 37-45 C for hyperthermia (1,2,5) or above 45 C for thermoablation, (3). In previous work, the heat has been induced using chemically synthesized nanoparticles, mainly in the form superparamagnetic iron oxide nanoparticles (SPION), which were either mixed in solution or mixed with cells or administered to a living organism (1)(2)(3)(4)(5)(6)(7)(8).…”

“…In this case, the destruction or elimination of tumors would occur by increasing the tumor temperature typically within the range of 37-45 C for hyperthermia (1,2,5) or above 45 C for thermoablation, (3). In previous work, the heat has been induced using chemically synthesized nanoparticles, mainly in the form superparamagnetic iron oxide nanoparticles (SPION), which were either mixed in solution or mixed with cells or administered to a living organism (1)(2)(3)(4)(5)(6)(7)(8). The anti-tumoral activity of these heated nanoparticles has been evaluated both on animal models and clinically on humans (1)(2)(3)(4)(5)(6)(7)(8).…”

“…In previous work, the heat has been induced using chemically synthesized nanoparticles, mainly in the form superparamagnetic iron oxide nanoparticles (SPION), which were either mixed in solution or mixed with cells or administered to a living organism (1)(2)(3)(4)(5)(6)(7)(8). The anti-tumoral activity of these heated nanoparticles has been evaluated both on animal models and clinically on humans (1)(2)(3)(4)(5)(6)(7)(8). The efficiency of this type of thermotherapy has been demonstrated on several cancers including brain cancer, (6), prostate cancer, (7), breast cancer, (8), and skin cancer, (4).…”

Synthesis and characterization of iron oxide magnetic nanoparticles

“…Magnetic nanoparticles (MNPs) have drawn much attention because they can be widely used in electronics [1], nanotechnology [2] and most of all in medicine [3][4][5]. In external magnetic fi elds they can be useful as contrast agents for magnetic resonance imaging (MRI) [6,7], as colloidal mediators for the treatment of cancer using magnetic hyperthermia [8,9] or as intelligent drug delivery systems [6].…”

An Intravascular Magnetic Catheter Enables the Retrieval of Nanoagents from the Bloodstream

“…Some efforts have been also devoted to make therapeutic nanovectors responsive to endogenous (such as changes in pH, temperature, redox conditions, or enzymes' activity) or exogenous (such as magnetic fields, ultrasound, and various types of irradiation) stimuli,11 in order to deliver therapy on demand12 and furtherly increase the TI. Magnetic nanoparticles play a major role in nanomedicine for being intrinsically theranostic: they can act as contrast agents in magnetic resonance imaging, but they can be also used for active tumor targeting (by exploiting an external magnetic field source enabling accumulation at the site of interest) and active therapy triggering both to enable drug delivery and magnetic hyperthermia 13, 14, 15…”