Magnetic hyperthermia of laponite based ferrofluid

• Published in: Journal of magnetism and magnetic materials Vol. 336; pp. 71 - 74
• Main Authors: Diamantopoulos, G., Basina, G., Tzitzios, V., Karakosta, E., Fardis, M., Jaglicic, Z., Lazaridis, N., Papavassiliou, G.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-06-2013; Elsevier
• Subjects: Amplitudes; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Ferrofluid; Hyperthermia; Iron oxides; Laponite disk; Magnetic liquids; Magnetic nanoparticle; Magnetic properties and materials; Nanocomposites; Nanomaterials; Nanoparticles; Nanostructure; Physics; RF heating; Studies of specific magnetic materials; Synthetic aperture radar; Laponite disk; Magnetic nanoparticle; Ferrofluid; RF heating; Ferromagnetic fluid; Iron oxide; Volume fraction; Low field; Heat treatments; Relaxation time; Brownian motion; Nanoparticles; Magnetic particles; Dissipation; Power losses; Hyperthermia
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2013.02.032

Magnetic Hyperthermia experiments have been performed on different concentrations of magnetic iron oxide nanoparticles immobilized on nano-clay disks. The specific absorption rate (SAR) was measured in AC field amplitudes H0 from 7 to 30kA/m. At low field amplitudes, SAR followed the usual H02 law whereas for higher field amplitudes a linear dependence was found for the higher concentrations. Measurements at three different field amplitudes were also performed for a wide range of iron oxide concentrations in order to determine the effect of the Brownian relaxation time to SAR. A field dependent maximum was observed and for fields up to 20kA/m the power dissipation losses were well explained according to theoretical predictions.
► Influence of the AC field to the specific absorption rates (SAR). ► Transition point from the expected square dependence to a linear law between SAR and AC field amplitude. ► A field dependent maximum of the SAR values versus iron oxide concentration is observed. ► Experimental validation of the existing theoretical work.