scholarly journals Methods for Estimating Specific Loss Power in Magnetic Hyperthermia Revisited

2016 ◽  
Vol 06 (12) ◽  
pp. 815-825 ◽  
Author(s):  
Kenya Murase
Keyword(s):  
Magnetic Hyperthermia ◽  
Specific Loss ◽  
Specific Loss Power

scholarly journals Role of zinc substitution in magnetic hyperthermia properties of magnetite nanoparticles: interplay between intrinsic properties and dipolar interactions

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Yaser Hadadian ◽  
Ana Paula Ramos ◽  
Theo Z. Pavan
Keyword(s):  
Magnetic Nanoparticles ◽  
Magnetite Nanoparticles ◽  
Linear Response Theory ◽  
Magnetic Hyperthermia ◽  
Superior Performance ◽  
Dipolar Interactions ◽  
Intrinsic Properties ◽  
Specific Loss ◽  
Heating Efficiency ◽  
Specific Loss Power

AbstractOptimizing the intrinsic properties of magnetic nanoparticles for magnetic hyperthermia is of considerable concern. In addition, the heating efficiency of the nanoparticles can be substantially influenced by dipolar interactions. Since adequate control of the intrinsic properties of magnetic nanoparticles is not straightforward, experimentally studying the complex interplay between these properties and dipolar interactions affecting the specific loss power can be challenging. Substituting zinc in magnetite structure is considered as an elegant approach to tune its properties. Here, we present experimental and numerical simulation results of magnetic hyperthermia studies using a series of zinc-substituted magnetite nanoparticles (ZnxFe1-xFe2O4, x = 0.0, 0.1, 0.2, 0.3 and 0.4). All experiments were conducted in linear regime and the results were inferred based on the numerical simulations conducted in the framework of the linear response theory. The results showed that depending on the nanoparticles intrinsic properties, interparticle interactions can have different effects on the specific loss power. When dipolar interactions were strong enough to affect the heating efficiency, the parameter σ = KeffV/kBT (Keff is the effective anisotropy and V the volume of the particles) determined the type of the effect. Finally, the sample x = 0.1 showed a superior performance with a relatively high intrinsic loss power 5.4 nHm2kg−1.

scholarly journals Magnetic nanoparticles hyperthermia in a non-adiabatic and radiating process

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
C. A. M. Iglesias ◽  
J. C. R. de Araújo ◽  
J. Xavier ◽  
R. L. Anders ◽  
J. M. de Araújo ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Loss Rate ◽  
Thermal Conductance ◽  
Magnetic Hyperthermia ◽  
Point Of View ◽  
Magnesium Ferrite ◽  
Specific Loss ◽  
Heat Loss Rate ◽  
Specific Loss Power

AbstractWe investigate the magnetic nanoparticles hyperthermia in a non-adiabatic and radiating process through the calorimetric method. Specifically, we propose a theoretical approach to magnetic hyperthermia from a thermodynamic point of view. To test the robustness of the approach, we perform hyperthermia experiments and analyse the thermal behavior of magnetite and magnesium ferrite magnetic nanoparticles dispersed in water submitted to an alternating magnetic field. From our findings, besides estimating the specific loss power value from a non-adiabatic and radiating process, thus enhancing the accuracy in the determination of this quantity, we provide physical meaning to a parameter found in literature that still remained not fully understood, the effective thermal conductance, and bring to light how it can be obtained from experiment. In addition, we show our approach brings a correction to the estimated experimental results for specific loss power and effective thermal conductance, thus demonstrating the importance of the heat loss rate due to the thermal radiation in magnetic hyperthermia.

scholarly journals Maximizing Specific Loss Power for Magnetic Hyperthermia by Hard-Soft Mixed Ferrites

Small ◽  
2018 ◽  
Vol 14 (29) ◽  
pp. 1800135 ◽  
Author(s):  
Shuli He ◽  
Hongwang Zhang ◽  
Yihao Liu ◽  
Fan Sun ◽  
Xiang Yu ◽  
...  
Keyword(s):  
Magnetic Hyperthermia ◽  
Specific Loss ◽  
Mixed Ferrites ◽  
Specific Loss Power

scholarly journals Specific Loss Power of Co/Li/Zn-Mixed Ferrite Powders for Magnetic Hyperthermia

Sensors ◽  
2020 ◽  
Vol 20 (7) ◽  
pp. 2151
Author(s):  
Gabriele Barrera ◽  
Marco Coisson ◽  
Federica Celegato ◽  
Luca Martino ◽  
Priyanka Tiwari ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Properties ◽  
Cation Distribution ◽  
Biomedical Applications ◽  
Magnetic Measurements ◽  
Magnetic Hyperthermia ◽  
Alternating Magnetic Field ◽  
Specific Loss ◽  
Specific Loss Power ◽  
Auto Combustion

An important research effort on the design of the magnetic particles is increasingly required to optimize the heat generation in biomedical applications, such as magnetic hyperthermia and heat-assisted drug release, considering the severe restrictions for the human body’s exposure to an alternating magnetic field. Magnetic nanoparticles, considered in a broad sense as passive sensors, show the ability to detect an alternating magnetic field and to transduce it into a localized increase of temperature. In this context, the high biocompatibility, easy synthesis procedure and easily tunable magnetic properties of ferrite powders make them ideal candidates. In particular, the tailoring of their chemical composition and cation distribution allows the control of their magnetic properties, tuning them towards the strict demands of these heat-assisted biomedical applications. In this work, Co0.76Zn0.24Fe2O4, Li0.375Zn0.25Fe2.375O4 and ZnFe2O4 mixed-structure ferrite powders were synthesized in a ‘dry gel’ form by a sol-gel auto-combustion method. Their microstructural properties and cation distribution were obtained by X-ray diffraction characterization. Static and dynamic magnetic measurements were performed revealing the connection between the cation distribution and magnetic behavior. Particular attention was focused on the effect of Co2+ and Li+ ions on the magnetic properties at a magnetic field amplitude and the frequency values according to the practical demands of heat-assisted biomedical applications. In this context, the specific loss power (SLP) values were evaluated by ac-hysteresis losses and thermometric measurements at selected values of the dynamic magnetic fields.

A standardisation protocol for accurate evaluation of specific loss power in magnetic hyperthermia

2019 ◽  
Vol 52 (25) ◽  
pp. 255001 ◽  
Author(s):  
A Makridis ◽  
S Curto ◽  
G C van Rhoon ◽  
T Samaras ◽  
M Angelakeris
Keyword(s):  
Magnetic Hyperthermia ◽  
Accurate Evaluation ◽  
Specific Loss ◽  
Specific Loss Power

scholarly journals Optimization Study on Specific Loss Power in Superparamagnetic Hyperthermia with Magnetite Nanoparticles for High Efficiency in Alternative Cancer Therapy

Nanomaterials ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 40
Author(s):  
Costica Caizer
Keyword(s):  
Magnetic Field ◽  
Magnetic Nanoparticles ◽  
Cancer Therapy ◽  
Tumor Cells ◽  
Heating Temperature ◽  
Magnetic Hyperthermia ◽  
Optimal Conditions ◽  
Specific Loss ◽  
Specific Loss Power ◽  
The Magnetic Field

The cancer therapy with the lowest possible toxicity is today an issue that raises major difficulties in treating malignant tumors because chemo- and radiotherapy currently used in this field have a high degree of toxicity and in many cases are ineffective. Therefore, alternative solutions are rapidly being sought in cancer therapy, in order to increase efficacy and a reduce or even eliminate toxicity to the body. One of the alternative methods that researchers believe may be the method of the future in cancer therapy is superparamagnetic hyperthermia (SPMHT), because it can be effective in completely destroying tumors while maintaining low toxicity or even without toxicity on the healthy tissues. Superparamagnetic hyperthermia uses the natural thermal effect in the destruction of cancer cells, obtained as a result of the phenomenon of superparamagnetic relaxation of the magnetic nanoparticles (SPMNPs) introduced into the tumor; SPMNPs can heat the cancer cells to 42–43 °C under the action of an external alternating magnetic field with frequency in the range of hundreds of kHz. However, the effectiveness of this alternative method depends very much on finding the optimal conditions in which this method must be applied during the treatment of cancer. In addition to the type of magnetic nanoparticles and the biocompatibility with the biological tissue or nanoparticles biofunctionalization that must be appropriate for the intended purpose a key parameter is the size of the nanoparticles. Also, establishing the appropriate parameters for the external alternating magnetic field (AMF), respectively the amplitude and frequency of the magnetic field are very important in the efficiency and effectiveness of the magnetic hyperthermia method. This paper presents a 3D computational study on specific loss power (Ps) and heating temperature (ΔT) which allows establishing the optimal conditions that lead to efficient heating of Fe3O4 nanoparticles, which were found to be the most suitable for use in superparamagnetic hyperthermia (SPMHT), as a non-invasive and alternative technique to chemo- and radiotherapy. The size (diameter) of the nanoparticles (D), the amplitude of the magnetic field (H) and the frequency (f) of AMF were established in order to obtain maximum efficiency in SPMHT and rapid heating of magnetic nanoparticles at the required temperature of 42–43 °C for irreversible destruction of tumors, without affecting healthy tissues. Also, an analysis on the amplitude of the AMF is presented, and how its amplitude influences the power loss and, implicitly, the heating temperature, observables necessary in SPMHT for the efficient destruction of tumor cells. Following our 3D study, we found for Fe3O4 nanoparticles the optimal diameter of ~16 nm, the optimal range for the amplitude of the magnetic field of 10–25 kA/m and the optimal frequency within the biologically permissible limit in the range of 200–500 kHz. Under the optimal conditions determined for the nanoparticle diameter of 16.3 nm, the magnetic field of 15 kA/m and the frequency of 334 kHz, the magnetite nanoparticles can be quickly heated to obtain the maximum hyperthermic effect on the tumor cells: in only 4.1–4.3 s the temperature reaches 42–43 °C, required in magnetic hyperthermia, with major benefits in practical application in vitro and in vivo, and later in clinical trials.

scholarly journals Study on Maximum Specific Loss Power in Fe3O4 Nanoparticles Decorated with Biocompatible Gamma-Cyclodextrins for Cancer Therapy with Superparamagnetic Hyperthermia

2021 ◽  
Vol 22 (18) ◽  
pp. 10071
Author(s):  
Costica Caizer ◽  
Isabela Simona Caizer
Keyword(s):  
Cancer Therapy ◽  
Fe3o4 Nanoparticles ◽  
Magnetic Hyperthermia ◽  
Organic Layer ◽  
Cellular Toxicity ◽  
Innovative Strategy ◽  
Specific Loss ◽  
Beneficial Effects ◽  
Specific Loss Power ◽  
Magnetite Fe3o4

Different chemical agents are used for the biocompatibility and/or functionality of the nanoparticles used in magnetic hyperthermia to reduce or even eliminate cellular toxicity and to limit the interaction between them (van der Waals and magnetic dipolar interactions), with highly beneficial effects on the efficiency of magnetic hyperthermia in cancer therapy. In this paper we propose an innovative strategy for the biocompatibility of these nanoparticles using gamma-cyclodextrins (γ-CDs) to decorate the surface of magnetite (Fe3O4) nanoparticles. The influence of the biocompatible organic layer of cyclodextrins, from the surface of Fe3O4 ferrimagnetic nanoparticles, on the maximum specific loss power in superparamagnetic hyperthermia, is presented and analyzed in detail in this paper. Furthermore, our study shows the optimum conditions in which the magnetic nanoparticles covered with gamma-cyclodextrin (Fe3O4–γ-CDs) can be utilized in superparamagnetic hyperthermia for an alternative cancer therapy with higher efficiency in destroying tumoral cells and eliminating cellular toxicity.

scholarly journals Specific loss power measurements by calorimetric and thermal methods on γ-Fe2O3 nanoparticles for magnetic hyperthermia

2019 ◽  
Vol 473 ◽  
pp. 403-409 ◽  
Author(s):  
Marco Coïsson ◽  
Gabriele Barrera ◽  
Carlo Appino ◽  
Federica Celegato ◽  
Luca Martino ◽  
...  
Keyword(s):  
Magnetic Hyperthermia ◽  
Fe2o3 Nanoparticles ◽  
Thermal Methods ◽  
Specific Loss ◽  
Specific Loss Power ◽  
Power Measurements
Sign in / Sign up

Export Citation Format

Share Document