Optimizing the heating properties of magnetic nanoparticles is of great importance for hyperthermia applications. Recent experimental results show that core/shell nanoparticles could give an increased specific absorption rate (SAR) compared to the magnetic oxide nanoparticles currently used. We have developed a modified phenomenological model based on the linear Néel-Brown relaxation model to calculate the SAR due to susceptibility losses in complex nanoparticles with ferromagnetic (FM) core/ferrimagnetic (FiM) shell morphology. We use the Monte Carlo (MC) simulation technique with the implementation of the Metropolis algorithm to investigate the effect of size and shape on the magnetisation behaviour of complex ferromagnetic/ferrimagnetic nanoparticles covered by a surfactant layer. The findings of our simulations are used as an input in our modified model for the calculation of the SAR. Our calculations show that for all the sizes and shapes the complex FM/FiM nanoparticles give higher SAR values than the pure ferrimagnetic ones due to their higher core saturation magnetisation. For all sizes the nanoparticles with the truncated cuboctahedral shape give the highest SAR values and the cubic ones the lowest ones. The decrease in the surfactant thickness results in an increase of the SAR values. Our results have the same characteristics as the available experimental data from Fe/Fe3O4 nanoparticles, confirming that the complex nanoparticles with core/shell morphology can optimise the heating properties for hyperthermia.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/c4nr07576e | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Prediction of pre-eclampsia using maternal hemodynamic parameters at 12 + 0 to 15 + 6 weeks.
Ultrasound Obstet Gynecol
January 2025
Department of Obstetrics and Gynaecology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, SAR, China.
Objectives: To compare the maternal hemodynamic profile at 12 + 0 to 15 + 6 weeks' gestation in women who subsequently developed pre-eclampsia (PE) and those who did not, and to assess the screening performance of maternal hemodynamic parameters for PE in combination with the Fetal Medicine Foundation (FMF) triple test, including maternal factors (MF), mean arterial pressure (MAP), uterine artery pulsatility index and placental growth factor.
Methods: This was a prospective case-control study involving Chinese women with a singleton pregnancy who underwent preterm PE screening at 11 + 0 to 13 + 6 weeks' gestation using the FMF triple test, between February 2020 and February 2023. Women identified as being at high risk (≥ 1:100) for preterm PE by the FMF triple test were matched 1:1 with women identified as low risk (< 1:100) for maternal age ± 3 years, maternal weight ± 5 kg and date of screening ± 14 days.
Synthesis and modification of novel thiazole-fused quinoxalines as new insecticidal agents against the cotton leafworm : design, characterization, bio-evaluation, toxicological effectiveness, and study their mode of action.
RSC Adv
January 2025
Department of Chemistry, Faculty of Science (Boys), Al-Azhar University 11884 Nasr City Cairo Egypt
Herein, novel thiazolo[4,5-]quinoxalin-2-ones 2-6 and thiazolo[4,5-]quinoxalin-2(3)-imines 7-9 were synthesized and characterized using elemental analysis, IR spectroscopy, and H/C NMR to confirm their structures. The efficacy of the newly designed thiazolo-quinoxalines 2, 3, 4, 5, 7, 8, and 9 against the cotton leafworm (2nd and 4th instar larvae) was evaluated, and results revealed insecticidal activity with variable and good mortality percentages. A SAR study was also discussed.
View Article and Find Full Text PDFThe Causal Effects of Lifestyle Factors on Osteoarthritis: A Two-sample Mendelian Randomisation Study.
Curr Rheumatol Rev
January 2025
Division of Trauma and Orthopaedics, Department of Surgery, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK.
Background: Modern sedentary lifestyles are prevalent among individuals with osteoarthritis. However, direct evidence linking such behaviours as causative factors of osteoarthritis remain limited due to the presence of confounding variables.
Objective: This study aims to determine the extent to which lifestyle factors have causal effects on osteoarthritis through a two-sample Mendelian randomisation (MR) study.
Revisiting the safety limit in magnetic nanoparticle hyperthermia: insights from eddy current induced heating.
Phys Med Biol
January 2025
Department of Physics, Aristotle University of Thessaloniki, University Campus, Thessaloniki, 54124, GREECE.
Magnetic nanoparticle hyperthermia (MNH) emerges as a promising therapeutic strategy for cancer treatment, leveraging alternating magnetic fields (AMFs) to induce localized heating through magnetic nanoparticles (MNPs). However, the interaction of AMFs with biological tissues leads to non-specific heating caused by eddy currents, triggering thermoregulatory responses and complex thermal gradients throughout the body of the patient. While previous studies have implemented the Atkinson-Brezovich limit to mitigate potential harm, recent research underscores discrepancies between this threshold and clinical outcomes, necessitating a re-evaluation of this safety limit.
View Article and Find Full Text PDFOvercoming Energy-Scaling Barriers: Efficient Ammonia Electrosynthesis on High-Entropy Alloy Catalysts.
Adv Mater
January 2025
Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, SAR, 999077, P. R. China.
Electrochemically converting nitrate (NO ) to value-added ammonia (NH) is a complex process involving an eight-electron transfer and numerous intermediates, presenting a significant challenge for optimization. A multi-elemental synergy strategy to regulate the local electronic structure at the atomic level is proposed, creating a broad adsorption energy landscape in high-entropy alloy (HEA) catalysts. This approach enables optimal adsorption and desorption of various intermediates, effectively overcoming energy-scaling limitations for efficient NH electrosynthesis.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!