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The present work investigates the effect of external alternating magnetic field (AMF) on the electrocatalytic activity of nickel (Ni), iron oxide magnetic nanoparticles (MNP), and Ni-MNP nanoparticles in the urea electro-oxidation reaction (UER) through chronoamperometry (CA) with amplitudes of AMF between 14.9 and 88.9 mT and a frequency of 224 kHz. Results indicate that the AMF between 29.8 and 88.9 mT had a significant impact on the efficiency of UER, increasing the current obtained from Ni-MNP nanoparticles supported on carbon cloth (Ni-MNP/CC) by up to 52.5%. Moreover, a linear relationship between the UER current and AMF amplitude was observed. The significant enhancement of the current in the UER process with Ni-MNP/CC as catalyst under the AMF is attributed to the local heat generated by MNP nanoparticles, boosting the UER process on nickel nanoparticles. This work represents the first investigation of AMF on the UER process. [Display omitted] • Urea electro-oxidation was enhanced under an external alternating magnetic field. • Magnetic hyperthermia shows to be a suitable strategy to boot urea electro-oxidation. • Iron oxide magnetic nanoparticles produce heat under an alternating magnetic field. • The heat produced nearby to the nickel particles enhances the urea electro-oxidation. [ABSTRACT FROM AUTHOR]

Finding the interrelation among the magnetic response of the heat mediators to an alternating magnetic field (AMF) and other relevant parameters in magnetic hyperthermia therapy (MHT) can give the possibility to accurately design high-performance nanostructured magnetic nanoparticles (MNPs). In this context, the present work investigates the effect of the zinc substitution on magnetic properties and heat-generating ability of poly vinyl alcohol-coated Zn-substituted cobalt ferrite nanoparticles (PZC NPs) with different zinc contents ( Z n x C o 1 − x F e 2 O 4 ; x = 0, 0.15, 0.3, 0.4, 0.5, 0.7), synthesized using hydrothermal-assisted co-precipitation method. The obtained results showed that the PZC NPs with an average particle size ∼ 15 nm exhibit ferrimagnetic features and their coercivity (H c) values decrease as the zinc content (x) increases. Moreover, as Z n 2 + replaces C o 2 + in the structure, saturation magnetization (M s) increases up to about 52 emu/g for PZC-30 NPs (x = 0. 3) and then decreases for higher Zn contents. The hyperthermia measurements were performed at a fixed filed frequency (f = 120 k H z) and different magnetic field strengths (H a p p l = 17 , 20 , 24. 5 k A / m). The results revealed that, as x increases, specific absorption rate (SAR) at each H a p p l first shows an increasing trend and then reaching a maximum value (at x = 0. 4) follows a decreasing trend. Moreover, the highest SAR (25.25 W/g) belongs to the magnetic fluid containing PZC-40 NPs at H a p p l = 24. 5 k A / m. Furthermore, the H a p p l -dependency of the SAR values were obtained as a power law ( S A R ∼ H a p p l n) in which the exponent n rises as x decreases, suggesting that the optimal composition tends to shift to ones with the lower x at higher H a p p l . The obtained results, revealing the high impact of the interrelation between the chemical composition and the H a p p l on the MNPs heating efficiency, can shed more light on the way to design heat mediators with optimal performance through simultaneous control of the chemical composition and the H a p p l . [ABSTRACT FROM AUTHOR]

Commendable efforts have been gingered towards the fight against cancer. Nevertheless, it remains a major public health concern due to its predominant cause of death globally. Given this, we synthesized two different nanoparticles, Sr2+ and Gd3+ doped magnetite for magnetic hyperthermia and drug delivery application. Based on the characterization, the diffractogram shows that only one phase related to magnetite with a crystallite size of 10 nm was formed. TEM images revealed nanoparticles of spherical shapes of approximately 12 nm. There is no difference in magnetic saturation of the as-received synthesized samples (Fe 3 O 4 @Sr and Fe 3 O 4 @Gd), while the BET-specific surface area of Fe 3 O 4 @Gd is 8 m2 g−1 higher than Fe 3 O 4 @Sr. The heat generation in alternating magnetic field (the magnetic hyperthermia) of Fe 3 O 4 @Sr functionalized with citric acid and loaded with 5- fluorouracil (Fe 3 O 4 @Sr@CA@5-flu) is slower than Fe 3 O 4 @Gd@CA@5-flu. The specific absorption rate (SAR) of Fe 3 O 4 @Gd@CA@5-flu, 112.0 ± 10.4 W g−1 was found to be higher than that of Fe 3 O 4 @Sr@CA@5-flu. The thermogram shows that 11% of the drug was successfully loaded on Fe 3 O 4 @Gd@CA@5-flu. The release of the antitumor drug by the synthesized nanoparticle drug carriers for ovarian cancer (SKOV-3 cells) therapy showed that more than 50% of the cancer cell's viability was reduced after 72 h of incubation. The synthesized nanoparticles demonstrated a promising drug carrier for the treatment of SKOV-3 cells. [ABSTRACT FROM AUTHOR]

Assemblies of magnetite nanoparticles created by the ultrasonic mechanocavitation in a viscous liquid have been obtained for use in magnetic hyperthermia. The magnetite nanoparticles inherit the perfect crystal structure of the original coarse-grained magnetite powder, with characteristic sizes of 0.2–8 μm, and have a high saturation magnetization, M s = 92 emu/g, close to the value of pure magnetite. Measurements of the specific absorption rate (SAR) of assemblies in an alternating (ac) magnetic field showed a significant dependence of SAR on the nanoparticle concentration, as well as on the shape of particle macroaggregates. A 4-fold increase in the SAR of elongated clusters of particles oriented parallel to the action of ac magnetic field was found in comparison with an assembly of quasi-spherical clusters. In addition a sharp dependence of the SAR of an assembly of elongated clusters on the ac magnetic field direction with respect to the cluster orientation axis was revealed. The results obtained are in qualitative agreement with the results of numerical simulation of dense clusters of magnetic nanoparticles based on the solution of the stochastic Landau-Lifshitz equation. [ABSTRACT FROM AUTHOR]

Yang et al. recently demonstrated the high potential of liquid metal microspheres (LM MSs) in cancer therapy. By amplifying the effects of magnetic hyperthermia and embolization, LM MSs not only target primary tumors, but also potentiate immune defenses. This dual-action approach effectively curtails distant tumor growth, marking a pivotal advancement in cancer immunotherapy. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is the most invasive brain tumor and remains lack of effective treatment. The existence of blood-brain tumor barrier (BBTB) constitutes the greatest barrier to non-invasive delivery of therapeutic agents to tumors in the brain. Here, we propose a novel approach to specifically modulate BBTB and deliver magnetic hyperthermia in a systemic delivery mode for the treatment of GBM. BBTB modulation is achieved by targeted delivering fingolimod to brain tumor region via dual redox responsive PCL-SeSe-PEG (poly (ε-caprolactone)-diselenium-poly (ethylene glycol)) polymeric nanocarrier. As an antagonist of sphingosine 1-phosphate receptor-1 (S1P 1), fingolimod potently inhibits the barrier function of BBB by blocking the binding of sphingosine 1-phosphate (S1P) to S1P1 in endothelial cells. We found that the modulated BBTB showed slight expression level of tight junction proteins, allowing efficient accumulation of zinc- and cobalt- doped iron oxide nanoclusters (ZnCoFe NCs) with enhanced magnetothermal conversion efficiency into tumor tissues through the paracellular pathway. As a result, the co-delivery of heat shock protein 70 inhibitor VER-155008 with ZnCoFe NCs could realize synergistic magnetic hyperthermia effects upon exposure to an alternating current magnetic field (ACMF) in both GL261 and U87 brain tumor models. This modulation approach brings new ideas for the treatment of central nervous system diseases that require delivery of therapeutic agents across the blood-brain barrier (BBB). [Display omitted] • A nano-modulator was developed to regulate the permeability of BBTB in brain tumors. • The nano-modulator shows tumor microenvironment accelerated drug release profile. • The nano-modulator can inhibit the biosynthesis route of tight junction between endothelial cells. • The co-delivery of magnetic nanoclusters and HSP 70 inhibitor exhibit synergistic therapy to GBM. [ABSTRACT FROM AUTHOR]

• Simulate the backflow behavior for nanofluid infusion inside bio-tissue under a geometric nonlinear model. • Investigate the bio-tissue deformation and its effect on the change of material property during nanofluid infusion. • Investigate the interstitial pressure and the local stress distribution inside bio-tissue due to the nanofluid infusion. • Effect of backflow on treatment temperature distribution and heat induced damage for malignant tissue. Although targeted magnetic hyperthermia has been proven to be an effective tumor ablation technique, its use in clinical applications is still scarce particularly due to the difficulty in imposing a desired nanofluid distribution in the therapeutic area. In addition to the inherent difficulty of imposing a distribution with few injection shots, during the nanofluid infusion, the tissue deformation can cause the nanofluid deviation from the targeted injection area and the backflow along the needle can deliver the injected nanofluid to the outer surface of the tissue. Both phenomena can result in an irregular distribution for nanofluid inside bio-tissue. This study develops a poroelastic model considering geometrically nonlinear behavior in order to evaluate the effect of syringe needle size and infusion rate on the backflow. A 26 gauge needle for syringe is used as a typical example to further investigate the nanofluid transport and the change of solid matrix material properties under different infusion rates after comparing the infusion results for several sizes of needle. Finally, the resulting nanofluid concentration distribution obtained with the proposed model is used to simulate the temperature distribution and the cancerous cell damage. The results demonstrate that the infusion pressure and its resulting tissue deformation are the fundamental reasons for obtaining an irregular solution distribution. Tissue deformation induces the increase of porosity and permeability for biomaterials around the tip, and enhances the fluidity of nanofluids inside the tissue. The results also indicate that the increase in backflow length can improve the uniformity of the nanofluid distribution after diffusion and, consequently, the treatment effect. However, it also increases the risk of MNP leakage from the targeted area to the tumor surface, so it is important to keep the backflow rate limited during the injection process. [ABSTRACT FROM AUTHOR]

In this study, novel magnetite (Fe 3 O 4)/mesoporous silica nanoparticles (MSN) were prepared by the green synthesis method using Moringa oleifera extract with various MSN concentrations. The crystallite size of Fe 3 O 4 /MSN decreased from 10.5 to 9.0 nm with the increase of MSN concentrations. However, as shown from transmission electron microscope images, the surface modification process increases its particle size from 10.7 ± 0.1–27.8 ± 0.3 nm. Scanning electron microscopy images revealed that MSN has a porous structure, and the shape of Fe 3 O 4 /MSN was nearly spherical. The Fourier transform infrared spectra showed the functional group of Si-O-Si at 1041 cm−1, indicating a successful surface modification process. After modification using MSN, the band gap energy of the nanoparticles decreased from 3.61 to 3.27 eV. The magnetic properties analysis showed that the saturation magnetization of Fe 3 O 4 and Fe 3 O 4 /MSN was 55.32 ± 0.03 emu/g and 53.45 ± 0.04 emu/g, respectively. In contrast, the coercivity increased from 57.7 ± 0.3–149.5 ± 0.5 Oe. Additionally, the specific absorption rate (SAR) of Fe 3 O 4 /MSN to evaluate its potential for magnetic hyperthermia applications were investigated. The highest SAR values of Fe 3 O 4 and Fe 3 O 4 /MSN were 91.8 mW/g and 86.7 mW/g, which decreased with increasing MSN concentrations. Furthermore, these results proved that the green-synthesized Fe 3 O 4 /MSN was a promising candidate and potentially optimized the performance of future magnetic hyperthermia applications. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Successful synthesis of superparamagnetic Zn x Fe 3-x O 4 ferrite nanoparticles with x ranging from 0 to 1. • Zn-Fe ferrite superparamagnetic nanoparticles exhibit tunable Curie temperature, between 42 and 853 K. • High saturation magnetizations, with great potential for magnetic induction heating applications. • Saturation magnetization highly dependent on Zn relative content, with a maximum around x = 0.25. • Optimized composition range for near room temperature self-regulated heating applications around x = 0.43. The control of the Curie temperature can be used as an intrinsic safety switch for magnetic induction heating applications, such as magnetic hyperthermia, heat generation devices and heat dissipation systems. In this work we used a coprecipitation method to synthesize Zn-Fe ferrite superparamagnetic nanoparticles (Zn x Fe 3-x O 4 : x = 0, 0.15, 0.25, 0.35, 0.50, 0.65, 0.75, 0.85, 1) to tune their Curie temperature. The produced Zn x Fe 3-x O 4 nanoparticles present diameters below 15 nm and crystallite sizes ranging from 10 to 4 nm, depending close to linearly on the Zn relative content. The Zn x Fe 3-x O 4 nanoparticles saturation magnetization is highly dependent on the Zn relative content, having a maximum around the Zn 0.25 Fe 2.75 O 4 composition. Finally, we propose an optimized composition range of these Zn-Fe ferrite superparamagnetic nanoparticles for near room temperature self-regulated heating n applications. [ABSTRACT FROM AUTHOR]

A characteristic feature of most magnetic materials is that they have a hysteresis cycle. When the magnetic field goes through the hysteresis cycle multiple times, the energy of the alternating magnetic field is supplied to magnetic nanoparticles located in the area of cancer cells. This energy supplied to the magnetic nanoparticles is converted into heat in the environment. As a result of heating to a certain temperature, diseased cells die, while healthy cells remain undamaged. This is the usual mechanism for heating a cancer tumor in hyperthermia. This work examines the possibility of heating a part of the body under the resonant influence of a radio frequency field. The resonant frequency is formed from the rotational flow of mean square fluctuations of magnetic nanoparticles. It has been shown that by selecting the parameters of the resonant field, it is possible to achieve an increase in tumor temperature by 6° (sufficient to destroy malignant cells) in about 60 s. [ABSTRACT FROM AUTHOR]

Multicore magnetic iron oxide nanoparticles, nanoflowers (NFs), have potential biomedical applications as efficient mediators for AC-magnetic field hyperthermia and as contrast agents for magnetic resonance imaging due to their strong magnetic responses arising from complex internal magnetic ordering. To realise these applications amenable surface chemistry must be engineered that maintain particle dispersion. Here a catechol-derived grafting approach is described to strongly bind polyethylene glycol (PEG) to NFs and provide stable hydrogen-bonded hydrated layers that ensure good long-term colloidal stability in buffers and media even at clinical MRI field strength and high concentration. The approach enables the first comprehensive study into the MRI (relaxivity) and hyperthermic (SAR) efficiencies of fully dispersed NFs. The predominant role of internal magnetisation dynamics in providing high relaxivity and SAR is confirmed, and it is shown that these properties are unaffected by PEG molecular weight or corona formation in biological environments. This result is in contrast to traditional single core nanoparticles which have significantly reduced SAR and relaxivity upon PEGylation and on corona formation, attributed to reduced Brownian contributions and weaker NP solvent interactions. The PEGylated NF suspensions described here exhibit usable blood circulation times and promising retention of relaxivity in-vivo due to the strongly anchored PEG layer. This approach to biomaterials design addresses the challenge of maintaining magnetic efficiency of magnetic nanoparticles in-vivo for applications as theragnostic agents. Application of multicore magnetic iron-oxide nanoflowers (NFs) as efficient mediators for AC-field hyperthermia and as contrast agents for MR imaging has been limited by lack of colloidal stability in complex media and biosystems. The optimized materials design presented is shown to reproducibly provide PEG grafted NF suspensions of exceptional colloidal stability in buffers and complex media, with significant hyperthermic and MRI utility which is unaffected by PEG length, anchoring group or bio-molecular adsorption. Deposition in the selected pancreatic tumour model mirrors liposomal formulations providing a quantifiable probe of tissue-level liposome deposition and relaxivity is retained in the tumour microenvironment. Hence the biomaterials design addresses the longstanding challenges of maintaining the in vivo magnetic efficiency of nanoparticles as theragnostic agents. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, CoFe 2 O 4 magnetic nanoparticles (MNPs) were synthesized by an eco-friendly co-precipitation method. The effect of Triethylene glycol (TEG) coating on the structural, magnetic and magnetothermal properties of MNPs was investigated. The formation of crystalline MNPs with a cubic spinel structure and the single phase state was confirmed by the X-ray diffraction (XRD) and infrared spectra (FT-IR) techniques. The spherical morphology and aggregation of the MNPs, as a sign of the presence of interparticle interactions, were revealed by the field emission scanning electron microscopy imaging. A remarkable result has been found by the SQUID and Mössbauer spectroscopy measurements revealing that the polymer coating increases the saturation magnetization through the control of the metal-oxygen-metal bonds and reduction of the spin disorder at the nanoparticle surface. Furthermore, the Henkel plots indicated a dominant role of the dipole-dipole over exchange magnetic interactions in the samples which affected the heating efficiency of the ferrofluids measured under different AC magnetic fields (2.2, 2.7, and 3.3 mT) with a frequency of 92 kHz showing a linear dependence of the thermal efficiency with the AC field amplitude. It was shown that TEG coating increases the heating efficiency of the CoFe 2 O 4 MNPs, which was attributed to an increase in saturation magnetization and a decrease in the strength of the magnetic interactions between the coated nanoparticles. [ABSTRACT FROM AUTHOR]

This study underscores the potential of nanocomposites of magnetite (Fe 3 O 4) with amine functionalized multi-walled carbon nanotube (MWCNT) for applications in magnetic hyperthermia therapy, by optimizing the amine-functionalized MWCNT concentration to maintain favorable interactions with Fe 3 O 4 , avoiding excessive aggregation, and maximizing the hyperthermia performance. The magnetic property analysis revealed that the presence of amine-functionalized MWCNTs influenced the saturation magnetization (M S) of the nanocomposites, surprisingly, the FC1 (composite with 1 % amine-functionalized MWCNT) and FC3 (composite with 3 % amine-functionalized MWCNT) nanocomposites exhibited higher saturation magnetization (M S) compared to bare Fe 3 O 4 , attributed to the enhanced interaction between Fe 3 O 4 and the amine-functionalized MWCNTs, which facilitated the cationic influx and alignment of surface spins. However, at higher concentrations of functionalized MWCNTs (FC7 and FC10), a reduction in M S was observed, possibly due to aggregation effects which can also be inferred from their cubic anisotropy value. Among the nanocomposites, FC3 exhibited the highest specific absorption rate (SAR), correlating with its enhanced M S , while FC10 showed the lowest SAR, consistent with its reduced M S. The SAR values were found to increase with the applied magnetic field amplitude, with FC3 surpassing bare Fe 3 O 4 at higher field amplitudes, likely due to the predominant effects of Néel relaxation mechanisms. The observed enhancement in magnetic properties at optimal MWCNT concentrations presents a promising pathway for the design of advanced magnetic nanocomposites with improved performance in hyperthermia applications. • Optimized Fe₃O₄/MWCNT nanocomposites enhance magnetic hyperthermia performance. • Amine-functionalized MWCNT improves Fe₃O₄ dispersibility and magnetic properties. • Fe₃O₄ made nanocomposite with 3 wt% amine functionalized MWCNT concentration showed maximum heat generation in magnetic hyperthermia. • High saturation magnetization (M S) achieved with Fe₃O₄/MWCNT composite nanostructures. • Reduced MWCNT aggregation leads to improved magnetic behaviour and therapeutic potential. [ABSTRACT FROM AUTHOR]

• MZCG DOX was prepared by controllable electrostatic assembly of Fe@ZIF-8. • MZCG DOX could be easily injected and heated under AMF. • MZCG DOX exhibited magnetic accelerated pH-responsive drug release. • Synergy of MHT and chemotherapy of MZCG DOX enhanced the HCC therapy. • MZCG as a new embolic agent could treat HCC by transarterial embolization. Thermal ablation is frequently combined with systemic chemotherapy for treating hepatocellular carcinoma (HCC). However, the side effects of systemic chemotherapy on normal tissues limit its clinical application. Herein, we report a magnetic and pH dual-responsive colloidal gel assembled by doxorubicin (DOX)-loaded magnetic ZIF-8 and gelatin nanoparticles for HCC. The magnetic colloidal gel shows improved injectability and high functional particle loading, which could be injected through a 27G needle with an injection force as low as 8.8 N at 150 mg/mL solid content. Meanwhile, this colloidal gel could be magnetically heated and accelerated release DOX under tumor microenvironment, which presents a synergistic therapeutic effect by combining magnetic hyperthermia and localized chemotherapy. Furthermore, this colloidal gel could be manually injected interventional under ultrasound-guidance, exhibiting effective deep tumor treatment effect. Due to the high solid content, suitable injectability, and mechanical properties, the colloidal gel is also a promising embolic agent for transarterial embolization in HCC treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hf x Fe 3-x O 4 nanoparticles were synthesized. • The TEM and VSM data confirmed that all samples were nanosized and superparamagnetic. • In vitro cytotoxicity studies showed that these Hf x Fe 3-x O 4 nanoparticles are cytocompatible. • The Hf x Fe 3-x O 4 nanoparticles offer a promising approach for hyperthermia treatment. In this research, non-toxic Hf x Fe 3-x O 4 nanoparticles have been proposed for magnetic hyperthermia applications. The effects of Hf amount on the structural, morphological, and magnetic properties of synthesized nanoparticles were studied. Analysis using XRD, TEM, and VSM confirmed the cubic spinel structure of the samples, with sizes below 20 nm and exhibiting superparamagnetic behavior. Different amounts of Hf x Fe 3-x O 4 nanoparticles were dispersed in water to examine their applicability for magnetic hyperthermia. The nanoparticles' nontoxicity was observed through a cell viability analysis of human fibroblasts 1132SK. The findings suggest that the synthesized nanoparticles are effective for magnetic hyperthermia applications. [ABSTRACT FROM AUTHOR]

Extensive research has been conducted on the manufacturing of nano ferrites, and their use in magnetic hyperthermia therapy has shown promising results in cancer treatment. This study aims primarily to provide an overview of the latest developments in the synthesis of magnetic nanoparticles (MNPs) for the treatment of hyperthermia. Magnetic nanoparticles are biocompatible and have a stable magnetic state, nano ferrites have become recognized as apex thermoseeds in biomedical applications, specifically for the treatment of magnetic hyperthermia. Employing dopant materials, biocompatible overlay, and preparation techniques, one may study the effectiveness of nano ferrites. Furthermore, specific requirements need to be met for using nano ferrites in cancer treatments like magnetic hyperthermia. These include low toxicity, biocompatibility, a higher specific absorption rate, a shorter time to reach the targeted hyperthermia temperature, crystalline size within the biological radius, and a lower dose of the nano ferrite. A potential resolution involves identifying the limitations and proposing enhanced nanocomposite materials that amplify their magnetic characteristics via a biocompatible overlay, all while optimizing the effectiveness and functioning of magnetic nanoferrites. To increase the effectiveness of ferrite nanoparticles in treating hyperthermia, this study will figure out their constraints and offer solutions for more effective ferrite-based nanocomposites that may prove to be a viable therapy option for cancer in the future. • The mechanism of magnetic hyperthermia substances and specialized techniques and magnetic, non-toxic substances are explored. • The effects of magnetic nanoparticles on magnetic hyperthermia performance are studied meticulously. • Analysing the MNPs' rapid internalization and heating effectiveness inside the tumour for treating hyperthermia. • Investigated the latitudes of potential future research and examined several limitations for magnetic hyperthermia. [ABSTRACT FROM AUTHOR]

For in vivo magnetic hyperthermia tests, which are typically conducted on small animal models, one of the objectives is the design of alternating current (AC) magnetic field applicators able to guarantee an effective activation of magnetic nanoparticles (MNPs). During therapy application, it is critical to optimize heat deposition due to MNPs and minimize side effects in healthy tissues. For an accurate treatment planning, it is required to carefully select the geometry of the applicator coils and their location with respect to the body, as a function of the position and size of the tumour target region. Additionally, one should preliminary estimate the impact of experimental conditions on the MNP heating efficiency and thus on their capability to induce a temperature increase in tissues. Biophysical constraints have also to be taken into account in the choice of AC magnetic field parameters (frequency and amplitude), to avoid eddy current effects as much as possible. In this study, we present realistic simulations of preclinical tests on a mouse model, evaluating thermal response under various experimental conditions. We investigate different field applicator configurations, including helical, Helmholtz and pancake coils, while also analysing the role of the amplitude and frequency of the supply current, as well as of the type and administered dose of MNPs. The temperature increase in tissues, resulting from the heating effects due to AC magnetic field exposure and MNP activation, is calculated by means of in-house finite element models that solve the low-frequency electromagnetic field problem and the bioheat transfer equation. This in silico approach, which is applicable to any type of field applicators and MNPs, has been demonstrated to provide useful insights for the optimization of in vivo experiments, enabling the design of safer and more effective treatments. • Thermal response evaluation under various experimental conditions is a key task for magnetic hyperthermia treatment planning. • This study proposes the use of in silico models for guiding the selection of applicator configurations in in vivo tests. • Optimal parameters are found varying applicator geometry, supply conditions, magnetic nanoparticle type and dose. [ABSTRACT FROM AUTHOR]

[Display omitted] • Key Aspects highlighted of our manuscript titled " Optimizing the Magnetic Field Strength and Concentration of Silica Coated Cobalt Ferrite Nanoparticles for Magnetic Hyperthermia" submitted to Inorganic Chemistry Communications , are: • Originality : Addressing the emerging approach of using MNPs for hyperthermia therapy. • Significance : Demonstrating the potential of SiO2 coated CoFe2O4 MNPs in cancer treatment. • Quality: Utilizing rigorous analytical techniques for characterization. • Relevance: Addressing practical challenges in hyperthermia therapy. • Contribution: Presenting novel findings on the synthesis and characterization of MNPs. A therapeutic breakthrough in cancer treatment has recently been made by using magnetic nanoparticles (MNPs) for heating in hyperthermia therapy. Unapproachable tumors are being effectively destroyed by focused heat produced by MNPs. The major challenges regarding practical application of this therapy include the control and improvement of induction heating ability of MNPs and hyperthermia temperature range between 42–47 °C, for secure treatment at targeted area. Here, in this study, we have reported the synthesis and characterization of core–shell structured silica-coated cobalt ferrite nanoparticles (SiO 2 coated CoFe 2 O 4 MNPs), which are potential candidates for use as heat source in magnetic hyperthermia therapy. The SiO 2 coated CoFe 2 O 4 MNPs were synthesized using the reverse micelle method, with the SiO 2 coating performed simultaneously during MNP synthesis. Various analytical tools were utilized for the characterization. The structural measurements were probed by X-ray diffraction (XRD). Monodisperse MNPs with nearly spherical core–shell structure was revealed by Transmission electron microscopy (TEM) results. The average diameter of MNPs obtained from TEM analysis was 15 nm. The surface coating of cobalt ferrite MNPs with silica was verified by Fourier transform infrared spectrometry (FTIR). The saturation magnetization values obtained using vibrating sample magnetometer (VSM) measurements were 45.74 emu/g, revealing the superparamagnetic nature of the nanoparticles. The heating efficiency of different concentrations of synthesized nanoparticles was evaluated in an aqueous solution under an alternating magnetic field of strength 5.5 kA/m at a frequency of 260 kHz. A saturation temperature of 42 °C was attained at an optimum concentration of 1.7 mg/mL, while a magnetic field strength of 3.9 kA/m achieved 42 °C at a fixed concentration of 3.5 mg/ml. The obtained specific absorption rate (SAR) values for all the samples were between 56.23 to 100.1 W/g. The correlation between SAR values, MNP concentration, and applied magnetic field strength was also examined. The high saturation magnetization, efficient heating rates, and high SAR values make our synthesized silica-coated cobalt ferrite nanoparticles promising candidates for magnetic hyperthermia treatments, potentially improving therapeutic outcomes for cancer patients. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sol-gel synthesized nickel ferrite nanoparticles underwent surface functionalization to make them suitable for biomedical applications. • Nickel ferrite nanoparticles modified with graphene oxide were further functionalized using PAMAM dendrimer through EDS-NHS coupling. • The hyperthermia heating efficiency of PAMAM-functionalized graphene oxide-modified nickel ferrite nanoparticles was demonstrated to be significant. Magnetic nanoparticles have garnered significant interest, offering a promising avenue for magnetic hyperthermia. In this study, nickel ferrite nanoparticles were successfully synthesized using green-mediated sol–gel approach and subsequently modified with graphene oxide and functionalized using G3 Polyamidoamine dendrimer. Saturation magnetization values obtained from VSM analysis were found to be 51.8 emu/g and 11.2 emu/g for bare and functionalized nickel ferrite nanoparticles, respectively. The functionalized nanostructure exhibited potential for hyperthermia applications, with a specific absorption rate of 16 W/g. The in-vitro cytotoxicity of the functionalized nickel ferrite nanoparticles shows cell viability of 94.55 %, underscoring the non-toxic nature of the functionalized material. [ABSTRACT FROM AUTHOR]

New synthetic approaches of nanoparticles (NPs) can be used for magnetic hyperthermia, destroying malignant cells without damaging healthy tissues. Here, a combination of co-precipitation and thermal decomposition techniques was employed to synthesize monodisperse CoFe 2 O 4 NPs. A mixture of oleylamine and oleic acid with different concentrations was utilized as a surfactant, significantly changing magnetic, morphological and structural properties of the NPs. Increasing the surfactant concentration from 1 to 7.5 mmol resulted in maximum and minimum coercivity and saturation magnetization of 420.0 Oe 73.6 emu/g, and 67.2 Oe and 48.3 emu/g, respectively, arising from the prevention of agglomeration and reduction in crystallite size. The first-order reversal curve analysis was employed to clarify the role of the surfactant in magnetic distributions and detailed characteristics. The specific loss power of the NPs was found to be tuned for the different surfactant concentrations, achieving a maximum of 268.5 W/g at 7.5 mmol for CoFe 2 O 4 NPs with enhanced superparamagnetic contribution in Néel and Brownian mechanisms. MTT assay of the NPs was also carried out, indicating their low cytotoxicity. [ABSTRACT FROM AUTHOR]

The design of new strategies to increase the effectiveness of the antibacterial treatments is a main goal in public health. So, the aim of the study was to achieve a local antibacterial directed therapy as novel alternative allowing both, the delivery of the drug at the target, while minimizing undesirable side effects, thus anticipating an enhanced effectiveness. Hence, we have developed an innovative nanoformulation composed by biomimetic magnetic nanoparticles functionalized with the antimicrobial peptide AS-48 and its potential against Gram-positive and Gram-negative bacteria, either by itself or combined with magnetic hyperthermia has been investigated. Besides, the physical properties, binding efficiency, stability and mechanism of action of this nanoassembly are analyzed. Remarkably, the nanoassembly has a strong bactericidal effect on Gram-positive bacteria, but surprisingly also on E. coli and, finally, when combined with magnetic hyperthermia, on P. aeruginosa and K. pneumoniae. The results obtained represent a breakthrough since it allows a local treatment of infections, reducing and concentrating the dose of antimicrobial compounds, avoiding secondary effects, including the resistance generation and particularly because the combination with magnetic hyperthermia helps sensitizing resistant bacteria to the bactericidal effect of AS-48. Thus, this new formulation should be considered a promising tool in the antibacterial fight. [ABSTRACT FROM AUTHOR]

Heterogeneous cancers are usually recalcitrant to the conventional treatment method involving chemotherapy and radiotherapy. This issue was addressed by development of magnetic hyperthermia therapy (MHT) based on Escherichia coli. To be functional, E. coli was constructed to display the bivalent anti-HER2 affibody (denoted ZH2) on cell surface. The ZH2-displayed strain was further equipped with the biotin-binding motif (AP) which was anchored on the inner leaflet of cell membrane. After permeabilization, the engineered E. coli was loaded with streptavidin-linked magnetic nanoparticles (SiMNPs). The biotinylated AP tethers it to SiMNPs through the biotin-streptavidin interaction. As a result, SiMNPs-loaded E. coli was selectively internalized by HER2-positive cancer cells. Following the application of alternating magnetic field, the viability of cancer cells decreased to 20%. The administration in vivo also significantly caused tumor regression in mice xenografted with human ovarian cancer cells. Overall, this study proposes a new strategy of targeted cancer therapy based on the E. coli -mediated MHT. 1. Engineering E. coli for surface display of anti-HER2 affibody. 2. Engineering E. coli to anchor the biotinylation motif onto the inner membrane. 3. Loading E. coli with magnetic nanoparticles (MNPs) by the biotin-streptavidin technology. 4. Performing magnetic hyperthermia with MNPs-loaded E. coli for targeted treatment of HER2-positive tumor in vivo. [Display omitted] [ABSTRACT FROM AUTHOR]

Immunotherapy is a rapidly developing area of cancer treatment due to its higher specificity and potential for greater efficacy than traditional therapies. Immune cell modulation through the administration of drugs, proteins, and cells can enhance antitumoral responses through pathways that may be otherwise inhibited in the presence of immunosuppressive tumors. Magnetic systems offer several advantages for improving the performance of immunotherapies, including increased spatiotemporal control over transport, release, and dosing of immunomodulatory drugs within the body, resulting in reduced off-target effects and improved efficacy. Compared to alternative methods for stimulating drug release such as light and pH, magnetic systems enable several distinct methods for programming immune responses. First, we discuss how magnetic hyperthermia can stimulate immune cells and trigger thermoresponsive drug release. Second, we summarize how magnetically targeted delivery of drug carriers can increase the accumulation of drugs in target sites. Third, we review how biomaterials can undergo magnetically driven structural changes to enable remote release of encapsulated drugs. Fourth, we describe the use of magnetic particles for targeted interactions with cellular receptors for promoting antitumor activity. Finally, we discuss translational considerations of these systems, such as toxicity, clinical compatibility, and future opportunities for improving cancer treatment. Magnetic materials enable a variety of distinct and promising pathways to treat cancer by immunotherapy. [Display omitted] [ABSTRACT FROM AUTHOR]

Magnetothermal therapy (MT) is a noninvasive cancer treatment that has shown great promise in recent years. However, the low magnetothermal efficiency of the existing magnetic nanoparticles used in MT has been an obstacle to their widespread applications. In this work, we report a new class of Fe-Co-Ni-Cu high-entropy magnetic nanoparticles (HEMNPs) with exceptional magnetothermal properties synthesized by a thermal decomposition method. The fabricated HEMNPs, having an average diameter of 60–70 nm, exhibited a saturation magnetization of 42.4 emu/g and coercivity of 129.5 Oe. The hyperthermia measurement reveals that the HEMNPs have a maximum specific loss power of 202 W/g at the concentration of 2 mg/ml under an alternating magnetic field with an intensity of 46 Oe and a frequency of 266 kHz, demonstrating the great potential for MT applications. Our results demonstrate that the high-entropy concept can be extended to develop high-performance magnetic nanoparticles for MT applications. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] Ex-situ functionalization of Fe 3 O 4 nanoparticles, synthesized using a coprecipitation method, with bio-compatible polycaprolactone (PCL) polymer is reported in this study. The formation of the crystalline structure of Fe 3 O 4 is confirmed from the X-ray diffraction patterns. The presence of the PCL polymer on the surface of the coated MNPs is confirmed using Fourier transform infrared and X-ray photoelectron spectroscopy techniques and thermogravimetric analysis. Scanning and transmission electron microscopy imaging studies reveal the nearly spherical morphology of the synthesized nanoparticles. Room temperature magnetization measurements show the superparamagnetic nature of the PCL coated nanoparticles with high saturation magnetizations varying from ∼61–66 emu/g. Further, the room temperature coercivity is found to be reduced by ∼78 % for the PCL coated nanoparticles, which is attributed to the lowering of the interparticle interactions upon surface functionalization. Magnetic fluid hyperthermia studies on the PCL coated nanoparticles dispersed in ∼1 wt% agar gel shows significant alternating magnetic field induced heating efficiency, with temperature rise in the vicinity of the hyperthermia limit (∼42 °C). The highest specific absorption rate is found to be ∼85.4 ± 3.9 W/g Fe , indicating an intrinsic loss power of ∼0.62 nHm2kg−1, which is significantly higher than the previously reported values for PCL coated Fe 3 O 4 MNPs. The field induced heating efficiency is found to be correlated with the saturation magnetization of the PCL coated nanoparticles. In vitro cytotoxicity studies on human breast cancer (MCF-7) cell lines confirm the superior bio-compatibility of the PCL coated Fe 3 O 4 nanoparticles. Superior field induced heating efficiency, coupled with good bio-compatibility makes the PCL functionalized Fe 3 O 4 nanoparticles a potential candidate for magnetic fluid hyperthermia. [ABSTRACT FROM AUTHOR]

Combination of different therapies is an attractive approach for cancer therapy. However, it is a challenge to synchronize different therapies for maximization of therapeutic effects. In this work, a smart composite scaffold that could synchronize magnetic hyperthermia and chemotherapy was prepared by hybridization of magnetic Fe 3 O 4 nanoparticles and doxorubicin (Dox)-loaded thermosensitive liposomes with biodegradable polymers. Irradiation of alternating magnetic field (AMF) could not only increase the scaffold temperature for magnetic hyperthermia but also trigger the release of Dox for chemotherapy. The two functions of magnetic hyperthermia and chemotherapy were synchronized by switching AMF on and off. The synergistic anticancer effects of the composite scaffold were confirmed by in vitro cell culture and in vivo animal experiments. The composite scaffold could efficiently eliminate breast cancer cells under AMF irradiation. Moreover, the scaffold could support proliferation and adipogenic differentiation of mesenchymal stem cells for adipose tissue reconstruction after anticancer treatment. In vivo regeneration experiments showed that the composite scaffolds could effectively maintain their structural integrity and facilitate the infiltration and proliferation of normal cells within the scaffolds. The composite scaffold possesses multi-functions and is attractive as a novel platform for efficient breast cancer therapy. [Display omitted] [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles (MNPs)-mediated magnetic hyperthermia therapy is garnering attention as a promising modality for tumor remission. This therapy combines localized nano-scale heating and reactive oxygen species-related immunologic effects. A critical aspect in optimizing this therapy involves understanding how nanoheaters' subcellular localizations influence the therapeutic efficacy and immunological effects of magnetic hyperthermia. Herein, we investigate these effects by focusing on the strategic localization of ferrimagnetic vortex-domain iron oxide (FVIO) nanorings within lysosomes and the cytoplasm of hepatocellular carcinoma (HCC) cells. The comparative analysis revealed that lysosomal-localized magnetic hyperthermia markedly increased apoptosis in Hepa1–6 cells and effectively induced immunogenic cell death (ICD). Mechanistically, lysosomal-localized magnetic hyperthermia led to Bid-associated apoptosis and caspase-1-dependent interleukin-1β (IL-1β) secretion, likely due to enhanced lysosomal membrane permeabilization. Moreover, it reduced calreticulin degradation and increased its presence at the cell membrane, thereby boosting ICD efficiency. In contrast, cytoplasmic-localized magnetic hyperthermia showed comparatively lesser impact than its lysosomal-localized counterpart. In vivo experiments reinforced the exceptional efficacy of lysosomal-localized magnetic hyperthermia, which notably enhanced dendritic cells activation and T cells infiltration in both tumors and lymph nodes, thereby triggering a robust antitumor immune response. Additionally, lysosomal-localized magnetic hyperthermia improved tumor vaccine efficacy and demonstrated the potential for sustaining long-term immune responses in antitumor treatments. This study highlights the crucial role of subcellular positioning of magnetic nanoheaters in determining the efficacy of antitumor immunological responses in magnetic hyperthermia therapy, offering valuable insights for future cancer treatment strategies. [Display omitted] • FVIO-DHCA and FVIO-CPP magnetic hyperthermia nano-agents were designed for localization within lysosomes and the cytoplasm. • Lysosomal-localized magnetic hyperthermia markedly outperformed its cytoplasmic counterpart in promoting apoptosis and ICD. • Lysosomal-localized magnetic hyperthermia could notably enhance in vivo antitumor immune response. • Identifying and validating effective intracellular magnetic hyperthermia targets for enhancing antitumor immune response. [ABSTRACT FROM AUTHOR]

Synthesis of high quality, narrow size distributed superparamagnetic nanoparticles with high saturation magnetization is imperative for biomedical and environmental remediation applications. This study reports the synthesis of narrow size distributed, small diameter, high-quality Zn 1-x Ni x Fe 2 O 4 (x = 0.1, 0.3 and 0.5) nanoparticles with increased saturation mass magnetization for localized superparamagnetic hyperthermia and photocatalysis applications. Narrow size distributed samples with around 10 nm average diameter were synthesized, in the presence of surfactant, by solvothermal reflux method. All the samples show good colloidal stability through electrostatic stabilization with zeta potentials around - 60 mV. The heating capacity or specific heat generation rate (SHR) of synthesized superparamagnetic nanoparticles was determined through the calorimetric method. The x = 0.1, 0.3 and 0.5 samples show SHR = 372, 399 and 410 W g−1 of nanoparticles, respectively, under 35.28 kA/m and 316 kHz field parameters. These SHR values are higher than that of samples synthesized by other methods. Similarly, saturation mass magnetization value increases with Ni2+ concentration in the sample. The enhancement was attributed to preferential octahedral ligand sites occupation by Ni2+ ions in spinel lattice due to high crystal field stabilization energy. Photocatalytic activity of all nanoparticles was studied by methylene blue (MB) dye degradation under visible light. The data shows that degradation efficiency increases with Ni2+ concentration in the sample. All samples were characterized through X-ray powder diffraction (XRPD) profile, transmission electron microscopy (TEM), Fourier transformed infrared spectra (FT-IR), zeta potential distribution curve, thermogravimetric analysis (TGA) curve, vibrating sample magnetometer (VSM), transient temperature curves, and UV–visible–NIR photo-absorption spectra. [ABSTRACT FROM AUTHOR]