Surface spin tunneling and heat dissipation in magnetic nanoparticles

2018 ◽  
Vol 5 (3) ◽  
pp. 036101 ◽  
Author(s):  
Jasnamol P Palakkal ◽  
Chinna Obula Reddy ◽  
Ajeesh P Paulose ◽  
Cheriyedath Raj Sankar
Keyword(s):  
Magnetic Nanoparticles ◽  
Heat Dissipation ◽  
Spin Tunneling ◽  
Surface Spin

scholarly journals Biomedical Applications of Biomaterials Functionalized with Magnetic Nanoparticles

2020 ◽  
Author(s):  
Matteo Bruno Lodi ◽  
Alessandro Fanti
Keyword(s):  
Magnetic Field ◽  
Drug Delivery ◽  
Magnetic Nanoparticles ◽  
Heat Dissipation ◽  
Hyperthermia Treatment ◽  
Prosthetic Implants ◽  
Magnetic Carriers ◽  
Magnetic Drug Delivery ◽  
Influence Parameter ◽  
Nonlinear Nature

The combination of magnetic nanoparticles and a biocompatible material leads to the manufacturing of a multifunctional and remotely controlled platform useful for diverse biomedical issues. If a static magnetic field is applied, a magnetic scaffold behaves like an attraction platform for magnetic carriers of growth factors, thus being a potential tool to enhance magnetic drug delivery in regenerative medicine. To translate in practice this potential application, a careful and critical description of the physics and the influence parameter is required. This chapter covers the mathematical modeling of the process and assesses the problem of establishing the influence of the drug delivery system on tissue regeneration. On the other hand, if a time-varying magnetic field is applied, the magnetic nanoparticles would dissipate heat, which can be exploited to perform local hyperthermia treatment on residual cancer cells in the bone tissue. To perform the treatment planning, it is necessary to account for the modeling of the intrinsic nonlinear nature of the heat dissipation dynamic in magnetic prosthetic implants. In this work, numeric experiments to investigate the physiopathological features of the biological system, linked to the properties of the nanocomposite magnetic material, to assess its effectiveness as therapeutic agents are presented.

scholarly journals Exchange bias properties and surface spin freezing in magnetic nanoparticles

2010 ◽  
Vol 9 ◽  
pp. 28-31 ◽  
Author(s):  
F.G. Silva ◽  
R. Aquino ◽  
J. Depeyrot ◽  
F.A. Tourinho ◽  
V. Dupuis ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Exchange Bias ◽  
Spin Freezing ◽  
Surface Spin

scholarly journals Hyperthermic effect of magnetic nanoparticles under electromagnetic field

2009 ◽  
Vol 3 (1-2) ◽  
pp. 103-109 ◽  
Author(s):  
Giovanni Baldi ◽  
Giada Lorenzi ◽  
Costanza Ravagli
Keyword(s):  
Magnetic Nanoparticles ◽  
Biomedical Applications ◽  
Cobalt Ferrite ◽  
Heat Dissipation ◽  
Crystal Size ◽  
Size Control ◽  
Magnetic Fluid Hyperthermia ◽  
Potential Applications ◽  
Long Time ◽  
Pass Through

Magnetic nanoparticles have attracted increasingly attention due to their potential applications in many industrial fields, even extending their use in biomedical applications. In the latter contest the main features of magnetic nanoparticles are the possibility to be driven by external magnetic fields, the ability to pass through capillaries without occluding them and to absorb and convert electromagnetic radiation in to heat (Magnetic Fluid Hyperthermia). The main challenges of the current works on hyperthermia deal with the achievement of highly efficiency magnetic nanoparticles, the surface grafting with ligands able to facilitate their specific internalisation in tumour cells and the design of stealth nanocomposites able to circulate in the blood compartment for a long time. This article presents the synthesis of cobalt ferrite nanoparticles dispersed in diethylene glycol via the so called polyol strategy and the crystal size control through successive synthesis steps. Preliminary heat dissipation evaluations on the prepared samples were carried out and the question of how particles sizes affect their magnetic and hyperthermic properties was addressed as well. Furthermore we will present how surface chemistry can be modified in order to change the dispersity of the product without affecting magnetic and hyperthermic properties. .

scholarly journals Recent Advances in Understanding Magnetic Nanoparticles in AC Magnetic Fields and Optimal Design for Targeted Hyperthermia

2013 ◽  
Vol 2013 ◽  
pp. 1-17 ◽  
Author(s):  
Hiroaki Mamiya
Keyword(s):  
Magnetic Nanoparticles ◽  
Optimal Design ◽  
Magnetic Fields ◽  
Heat Dissipation ◽  
Magnetic Hysteresis ◽  
Hysteresis Loops ◽  
Future Prospects ◽  
Hyperthermia Treatment ◽  
Selective Heating ◽  
Magnetic Hysteresis Loops

Targeted hyperthermia treatment using magnetic nanoparticles is a promising cancer therapy that enables selective heating of hidden microcancer tissues. In this review, I outline the present status of chemical synthesis of such magnetic nanoparticles. Then, the latest progress in understanding their heat dissipation mechanisms under large magnetic fields is overviewed. This review covers the recently predicted novel phenomena: magnetic hysteresis loops of superparamagnetic states and steady orientations of easy axes at the directions parallel, perpendicular, or oblique to the AC magnetic field. Finally, this review ends with future prospects from the viewpoint of optimal design for efficacy with a low side-effect profile.

scholarly journals Hydrothermal Novel Synthesis of Neck-structured Hyperthermia-suitable Magnetic (Fe3O4, γ-Fe2O3 and α-Fe2O3) Nanoparticles

2011 ◽  
Vol 4 (1) ◽  
pp. 99 ◽  
Author(s):  
M. S. Islam ◽  
J. Kurawaki ◽  
Y. Kusumoto ◽  
M. Abdulla-Al-Mamun ◽  
M. Z. Bin Mukhlish
Keyword(s):  
Particle Size ◽  
Electron Microscope ◽  
Magnetic Nanoparticles ◽  
Quantum Interference ◽  
Heat Dissipation ◽  
Magnetic Hysteresis ◽  
Hysteresis Loops ◽  
Particle Morphology ◽  
Ferrous Chloride ◽  
Size And Morphology

Novel neck-structured Fe3O4, γ-Fe2O3 and α-Fe2O3 magnetic nanoparticles were successfully prepared by a modified hydrothermal method. Ferrous chloride tetrahydrate was solely used as a precursor for the novel nanomaterials. The X-ray diffractometric study revealed the purity of the nanomaterials thus synthesized. All of the products were characterized using a field-emission scanning electron microscope (FE-SEM) and a transmission electron microscope (TEM) for the particle size and morphology. Neck-structured particle morphology was observed for the first time in all of iron oxides with magnetic properties. The particle size observed was 50–60 nm. The synthesized nanomaterials showed excellent magnetization values when magnetic hysteresis loops were measured using a superconducting quantum interference device (SQUID). Moreover, the as-prepared magnetic nanoparticles suspensions showed significant temperature increments under an AC (alternating current) magnetic-field induction condition at room temperature which indicates the hyperthermia feasibility. Keywords: Magnetic materials; Neck-structured; Hyperthermia; Heat dissipation. © 2012 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. doi: http://dx.doi.org/10.3329/jsr.v4i1.8727J. Sci. Res. 4 (1), 99-107 (2012)

scholarly journals Magnetization Reversal and Specific Loss Power of Magnetic Nanoparticles in Cellular Environment Evaluated by AC Hysteresis Measurement

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Satoshi Ota ◽  
Tsutomu Yamada ◽  
Yasushi Takemura
Keyword(s):  
Magnetic Nanoparticles ◽  
Theoretical Model ◽  
Single Cell ◽  
Magnetization Reversal ◽  
Heat Dissipation ◽  
Magnetic Moments ◽  
Hysteresis Loops ◽  
Dipole Interactions ◽  
Fixed Sample ◽  
Cellular Environment

The effect of intracellular hyperthermia induced by magnetic nanoparticles (MNPs) has been evaluated using a theoretical model. In this study, magnetization reversal of MNPs in the cellular environment under an AC magnetic field was evaluated on the basis of measured AC hysteresis loops. The specific and intrinsic loss powers—SLP and ILP—were also estimated from the area of AC hysteresis loops. The measured samples were a liquid sample dispersed in water, a fixed sample mixed with an epoxy bond, and a cellular sample. In the cellular environment, the rotations of particles and magnetic moments were inhibited by particle-cell and dipole-dipole interactions, respectively. The heat dissipation of the MNPs in the cellular environment was lower than that of the liquid and fixed samples. Moreover, the SLP in a single cell was estimated. The temperature increase of a single cell was calculated on the basis of the conventional theoretical model and the SLP measured in a single cell.

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