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This study investigates the effects of Mn-Zn ferrite (MZF) content and heat treatment temperature on the structural, mechanical, magnetic, and bioactive properties of Na 2 O-CaO-P 2 O 5 glass ceramics. Various MZF contents (5MZF, 10MZF, 20MZF, and 40MZF) were incorporated into the glass ceramics and subjected to heat treatment at different temperatures (600, 650, 700, and 800 °C). The results demonstrated that increasing the MZF content significantly enhanced the mechanical properties, including Vickers hardness, Knoop hardness, and Young's modulus. For example, the Vickers hardness values increased from 5.6 GPa in 5MZF samples to 7.1 GPa in 40MZF samples. X-ray diffraction analysis revealed the presence of major crystalline phases, such as Ca 2 P 2 O 7 and Na 4 Ca(PO 3) 6 , with NaFe 3 P 3 O 12 and (Zn,Mn)Fe 2 O 4 appearing in samples with higher MZF content. Magnetic measurements indicated that the 40MZF samples treated at 700 °C reached a satisfactory hyperthermia temperature of 43 °C within 16 min. Bioactivity tests showed a decrease in bioactivity with increasing MZF content, whereas cytotoxicity assays confirmed that all MZF-Na 2 O-CaO-P 2 O 5 bioactive glass ceramics were non-toxic, maintaining over 100 % cell viability after 24 h. These findings suggest that MZF-containing glass ceramics have potential applications in the biomedical field, particularly when enhanced mechanical and magnetic properties are required. [ABSTRACT FROM AUTHOR]

Molecule hydrogen (H 2) has been used to suppress tumor growth. To employ the H 2 therapy, it is necessary to use a proper agent for continuous generation of H 2. As a biodegradable metal, magnesium (Mg) generates H 2 in an aqueous environment, but the H 2 release rate is still too low. Here, we design a Mg-Al-Ca (AX) alloy that degrades very rapidly due to the presence of a secondary phase Al 2 Ca. Having a reduction potential much higher than Mg and any other Mg-based secondary phases, Al 2 Ca accelerates the corrosion of the Mg matrix by a micro-galvanic process. Al 2 Ca also enhances the strength and ductility of the AX alloy. AX alloy rods show better anti-tumor efficacy than pure Mg rods in vivo. Moreover, implanted AX alloy rods can be heated under an alternating magnetic field to suppress large-size tumors. This work suggests that the H 2 therapy using highly degradable Mg alloys may provide an effective cancer treatment. [ABSTRACT FROM AUTHOR]

• Pointwise antenna design in hyperthermia therapy. • Sensitivity analysis of coupled multiphysics system. • First and second order antenna design algorithms. • Capability in selectively heating several targets simultaneously. • Numerical validation in a full transient analysis. This work deals with pointwise antennas design in hyperthermia treatment. Hyperthermia is a non-invasive therapy usually combined with chemotherapy and/or radiotherapy, which consists in heating the diseased tissue in an attempt to kill the cancerous cells. In particular, we want to find the optimal values of current densities passing through each antenna to selectively heat a specified target. The forward problem is governed by the steady-state heat equation in living tissues which is coupled with the Helmholtz problem modeling the electromagnetism phenomenon. An objective functional measuring the difference between the target temperature and the solution to the model problem is minimized with respect to the current densities by using the topological derivative method. The resulting sensitivities are used to devise first and second order antenna design algorithms as well as a third one that combines both the previous algorithms. Numerical experiments are presented showing different features of the proposed methodology, including its capability in selectively heating the target up to the desired temperature. Finally, a selected result is used in a full transient analysis, where the hot spots are keeping over the diseased tissues during the whole heating process. [ABSTRACT FROM AUTHOR]

• Impacts of reduced vessel radius and flow velocity on LIPU-induced thermal effect was studied. • In vivo ischemia model constructed by artery ligation to narrow vessel and reduce flow velocity. • FEM study showed reduced flow velocity enhancing LIPU heating by impairing heat dissipation. • Exponential relationship was fitted between LIPU-induced temperature rise and blood flow rate. • Findings enable prediction of LIPU thermal effect in ischemic tissues to ensure safe therapy. Ischemic diseases due to arterial stenosis or occlusion are common and can have serious consequences if untreated. Therapeutic ultrasound like high-intensity focused ultrasound (HIFU) ablates tissues while low-intensity pulsed ultrasound (LIPU) promotes healing at relatively low temperatures. However, blood vessel cooling effect and reduced flow in ischemia impact temperature distribution and ultrasonic treatment efficacy. This work established a rabbit limb ischemia model by ligating the femoral artery, measuring vascular changes and temperature rise during LIPU exposures. Results showed the artery diameter was narrowed by 46.2% and the downstream velocity was reduced by 51.3% after ligation. Finite element simulations verified that the reduced flow velocity impaired heat dissipation, enhancing LIPU-induced heating. Simulation results also suggested the temperature rise was almost related linearly to vessel diameter but decayed exponentially with the increasing flow velocity. Findings indicate that the proposed model could be used as an effectively tool to model the heating effects in ischemic tissues during LIPU treatment. This research on relating varied ischemic flow to LIPU-induced thermal effects is significant for developing safe and efficacious clinical ultrasound hyperthermia treatment protocols for the patients with ischemic diseases. [ABSTRACT FROM AUTHOR]

Treatment for different diseases has been revolutionized dramatically due to the advancements in the medical sciences, such as the practice of capped nanoparticles to treat carcinoma could be a promising strategy for future. For the first time we show that capping agents enhance the magnetization power while simultaneously reduce the particles size as well. Different capped iron oxide nanoparticles (Fe 3 O 4 -NPs) were synthesized using different organic ligands viz. citric acid and malic acid through co-precipitation method. Compared with un-capped particles, the capped-NPs exhibited reduction in size and cubic spinal structure as confirmed by TEM images and XRD peaks. Moreover, SEM images revealed that the organic acid functionalized NPs had irregular geometries in comparison with uncapped NPs. The presence of -OH -CH 2 and –COOH groups were confirmed by FTIR and variations in magnetic field were recorded using VSM. For in vivo bioassay, capped magnetic NPs were injected inside tumor cells followed by exposure to alternating magnetic fields. Exposure to alternating magnetic field of 15 mT and frequency 100 kHz for 1 h caused rise in temperature from 37 to 48 °C and also resulted in cellular damage and subsequent apoptotic cell death. In an overall assessment, functionalized Fe 3 O 4 -NPs exhibited reduction in particle size, increased magnetization properties and enhanced efficacy for carcinoma treatments by hyperthermia. Image 1 • Narrow range particles size (less than 5 nm). • Enhance the magnetization power with capping agents (CA). • Non-uniform size control the heating effect inside the tumor. • Reduce the tumor after each treatment using hyperthermia therapy. • Apoptotic cell death (due to temperature). [ABSTRACT FROM AUTHOR]

Abstract We have reported the synthesis of core-shell nanostructure of mesoporous silica coated lanthanum strontium manganese oxide nanoparticles (MSLN) as a potential candidate for cancer treatment via magnetic hyperthermia. N 2 adsorption-desorption isotherm revealed that mesoporous silica shell coating increased the surface area and pore volume of lanthanum strontium manganese oxide nanoparticles (LSMO). In comparison to LSMO, MSLN showed a stable colloidal dispersion up to 48 h. In-vitro studies using A549 cells demonstrated increased biocompatibility in MSLN as compared to LSMO. Moreover, cells treated with MSLN exhibited high cell survival rate of up to 1 mg/ml concentration. Further, we used different parameters to modulate the heating efficacies of these nanoparticles. The modulation of specific absorption rates (SAR) with different sample concentrations (0.5, 1, 1.5, 2.0 mg/ml) were studied under four different alternating current magnetic field (AMF) amplitudes (10, 11, 12, 13 kA/m) at a constant frequency of 335 KHz for magnetic hyperthermia experiments. Under the application of AMF, MSLN exhibited faster Néel and Brownian relaxation compared to their LSMO counterparts. SAR value of 295 W/g and intrinsic loss power (ILP) of 5.22 nHm2/kg, at a low sample concentration of MSLN (0.5 mg/ml) were obtained, which was within the clinical limit. Interestingly, our results showed 45% improvement in terms of the heating efficiency over the commercially available products (Table 3). Hence, we conclude that MSLN with high SAR and ILP values, good colloidal dispersion ability and low cytotoxicity could be a potential candidate for magnetic hyperthermia therapy in cancer and warrant further testing in both in-vitro and in-vivo studies. Further, due to their mesoporous nature, MSLN could be considered for target-specific drug delivery applications in clinical therapy. Highlights • Mesoporous silica-coated lanthanum strontium manganese oxide nanoparticles (MSLN) were synthesized. • Structural parameters of lanthanum strontium manganese oxide (LSMO) were calculated using Rietveld refinement software. • MSLN showed a larger surface area and pore volume as compared to LSMO. • MSLN exhibited better colloidal dispersion and enhanced biocompatibility than LSMO nanoparticles. • MSLN showed high specific absorption rate (SAR; 295W/g) as well as high intrinsic loss power (ILP; 5.22 nHm2kg−1). [ABSTRACT FROM AUTHOR]

Abstract This work reports a new approach of synthesis of FePt nanoparticles in aqueous medium using cetyl trimethylammonium bromide (CTAB) surfactant as a capping agent and the influence of change of its concentration on the size of the particles. Tuning of magnetic properties has also been done by changing the CTAB concentrations. Here at higher CTAB concentration, particles formed are of smaller size compared to the size prepared in lower micellar concentration. The ordering parameter of the particles after annealing at 550 °C with the variation of particle size is also studied. The magnetic properties of these particles are studied and the effect of particle phase and size on magnetic property is also investigated. The particles are prepared in aqueous medium because water soluble particles are useful for hyperthermia therapy. Heating abilities of the particles under AC magnetic field are also checked with change in their size. The studies on interaction of particles with cancer cell line was also performed with probing the cell by fluorescence imaging technique after bio-functionalization of the particles by sodium oleate and fluorescent dye rhodamine-B-isothiocyanate (RITC). All these preliminary studies indicate a promising applicability of the particles for localized cancer treatment by magnetic field induced hyperthermia therapy. [ABSTRACT FROM AUTHOR]

Highlights • Cobalt Ferrite magnetic nanoparticles were synthesized on DNA scaffold, in different batches. • Changes in different properties for the different batches of particles were observed by different methods, which affirms the binding of the MNP with the DNA. • Change in magnetic properties helped us to choose the suitable particle for magnetic hyperthermia therapy. Abstract In this work, we report that tuning of magnetic properties of cobalt ferrite magnetic nanoparticles (CFMNPs) is possible by combining them with some suitable organic molecules like DNA for hyperthermia therapy. Different batches of CFMNPs were synthesized on DNA scaffold (with varying the DNA concentrations for different batches) by wet chemical co-precipitation method. Final product was characterized by Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscope (SEM) for biological samples, Transmission electron microscope (TEM), Superconducting quantum interference device (SQUID), X-ray diffraction (XRD), Isothermal Titration Calorimetry (ITC) etc. From XRD data it was confirmed that the above mentioned nanoparticles are cobalt ferrite in pure phase and from FT-IR, SEM and TEM analyses, it was observed that cobalt ferrite nanoparticles were properly attached with DNA. Changes in magnetic properties with change of DNA amount for different batches were investigated by SQUID magnetometer. Heating ability under alternating current (AC) magnetic field for different batches of particles was investigated. It was observed that heating property was changing with change in DNA concentration. So it can be concluded that we have synthesized particles where DNA plays a very important role in tuning the magnetic properties which may give us opportunity to customize the particles for hyperthermia therapy. [ABSTRACT FROM AUTHOR]

This article discussed a numerical study of dual-phase-lag (DPL) bioheat transfer model with nonlocal impact on skin tissue during hyperthermia therapy when Gaussian type heat device is applied to the skin's outer surface. With the aid of a sufficient value of the parameters η , Q ro and r p for a heating device of the Gaussian type, the temperature distribution at the targeted location is controlled and maintained. These parameters are employed to destroy a significant number of cancer cells in the targeted location while protecting the surrounding healthy tissue. The temperature profile at the targeted location decreases as lagging time τ q and τ T increases, and increases as spatial lagging λ q increases. The blood perfusion effect can be shown when the value of α increases or when blood temperature decreases then it is seen that the temperature profile decreases. The numerical results obtained by the Finite element Legendre wavelet Galerkin (FELWG) approach are compared with the analytical results obtained in the specific situation to evaluate the precision. The obtained numerical results logically relate to the analytical results when we utilized the operational matrix of order M − 1 (where M = 100). All impacts of problem parameters are graphically represented during hyperthermia treatment. [ABSTRACT FROM AUTHOR]

• Ni 0.5 Zn 0.4 Cu 0.1 Fe 2 O 4 ferrite nanoparticles were prepared and incorporated in the titanium dioxide matrix. • Structural and morphological insvestigations were carried out. • Investigation of the magnetic and Mössbauer spectra revealed the presence of superparamagnetic phenomena. • The microwave reflection loss enhances significantly in the incorporated sample. • Considerable specific absorption rate was observed during inductive heating study of the samples. Ni 0.5 Zn 0.4 Cu 0.1 Fe 2 O 4 ferrite nanoparticles (NZCUFO) were prepared using a conventional co-precipitation method. The NZCUFO nanoparticles were then combined with titanium dioxide matrix to make the nanocomposite of [TiO 2 ] 0.2 [Ni 0.5 Zn 0.4 Cu 0.1 Fe 2 O 4 ] 0.8 (TNZCUFO). The formation of the appropriate crystallographic phase was confirmed by analyzing the X-ray diffraction pattern of the samples. Investigations extracted from the X-ray fluorescence spectroscopy, high-resolution transmission electron microscopy, and Raman spectroscopy imply the successful association of ferrite nanoparticles into the TiO 2 matrix. At 300 K, the saturation magnetization of NZCUFO and TNZCUFO reaches 34.6 and 23.4 emu/g, respectively. Mössbauer spectra recorded at 77 and 300 K indicate the presence of superparamagnetic behavior. These results were in agreement with the data obtained from magnetic hysteresis loop, zero field cooled, and field-cooled magnetization measurements. Both the samples were exposed to alternating current inductive heating and the extracted results successfully satisfy the condition of hyperthermia therapy for cancer treatment. The electromagnetic wave absorption capabilities of the samples were measured in the microwave region (8–18 GHz). The microwave reflection loss reaches −13.6 dB at 11.6 GHz and −29.7 dB at 11 GHz for the 2 mm thick samples of NZCUFO and TNZCUFO, respectively. The balanced matching of magnetic and dielectric loss, high magnetization, and specific absorption rate of the samples would be extremely useful for diverse soft magnetic applications. [ABSTRACT FROM AUTHOR]

Chemothermal brachytherapy seeds have been developed using a combination of polymeric dual drug chemotherapy and alternating magnetic field induced hyperthermia. The synergistic effect of chemotherapy and hyperthermia brachytherapy has been investigated in a way that has never been performed before, with an in-depth analysis of the cancer cell inhibition property of the new system. A comprehensive in vivo study on athymic mice model with SCC7 tumor has been conducted to determine optimal arrays and specifications of the chemothermal seeds. Dual drug chemotherapy has been achieved via surface deposition of polydopamine that carries bortezomib, and also via loading an acidic pH soluble hydrogel that contains 5-Fluorouracil inside the chemothermal seed; this increases the drug loading capacity of the chemothermal seed, and creates dual drug synergism. An external alternating magnetic field has been utilized to induce hyperthermia conditions, using the inherent ferromagnetic property of the nitinol alloy used as the seed casing. The materials used in this study were fully characterized using FESEM, H 1 NMR, FT-IR, and XPS to validate their properties. This new approach to experimental cancer treatment is a pilot study that exhibits the potential of thermal brachytherapy and chemotherapy as a combined treatment modality. [ABSTRACT FROM AUTHOR]

In self-controlling hyperthermia therapy, once the desired temperature is reached, the heat generation ceases and overheating is prevented. In order to design a system that generates sufficient heat without thermal ablation of surrounding healthy tissue, a good understanding of temperature distribution and its change with time is imperative. This study is conducted to extend our understanding about the heat generation and transfer, temperature distribution and temperature rise pattern in the tumor and surrounding tissue during self-controlling magnetic hyperthermia. A model consisting of two concentric spheres that represents the tumor and its surrounding tissue is considered and temperature change pattern and temperature distribution in tumor and surrounding tissue are studied. After describing the model and its governing equations and constants precisely, a typical numerical solution of the model is presented. Then it is showed that how different parameters like Curie temperature of nanoparticles, magnetic field amplitude and nanoparticles concentration can affect the temperature change pattern during self-controlling magnetic hyperthermia. The model system herein discussed can be useful to gain insight on the self-controlling magnetic hyperthermia while applied to cancer treatment in real scenario and can be useful for treatment strategy determination. [ABSTRACT FROM AUTHOR]

• Fe 3 O 4 magnetic nanocarriers for doxorubicin delivery and hyperthermia therapy. • Grafting of malic acid provides hydrophilicity and desired sites for drug binding. • Superparamagnetic nanocarriers with good external magnetic field responsivity. • pH dependent release and dose dependent toxicity of conjugated drug molecules. • Substantial cellular uptake of doxorubicin conjugated nanocarriers in MCF-7 cells. [Display omitted] Tailoring surface features is essential for creating specific functional properties on superparamagnetic Fe 3 O 4 nanoparticles for biomedical applications. In this regard, we explored the use of malic acid as a surface passivating agent for designing biocompatible, highly water-dispersible Fe 3 O 4 magnetic nanocarriers (MMNCs) for high payload of anticancer drug, doxorubicin hydrochloride (DOX). The efficacious grafting of malic acid onto the surface of Fe 3 O 4 was apparent from infrared spectroscopy, dynamic light scattering, zeta-potential and thermogravimetric measurements. XRD and TEM analyses revealed the formation of highly crystalline single-phase Fe 3 O 4 nanoparticles. They showed good aqueous colloidal stability, pH dependent surface charge characteristics and superparamagnetic behavior at room temperature. The electrostatic conjugation of drug onto the surface of MMNCs was optimized by varying the ratio of DOX to MMNCs, and a maximum loading efficiency of 72% was achieved at their 1:10 ratio. The DOX conjugated MMNCs (DOX-MMNCs) exhibited pH dependent controlled release characteristics. These DOX-MMNCs demonstrated dose dependent cellular uptake and retained considerable toxicity of DOX towards breast cancer (MCF-7) cell line. Further, our magnetic hyperthermia studies showed excellent heating efficiency of these MMNCs within the permissible limit of field strength and frequency reported for a safe application of hyperthermia to patients. Specifically, a water-dispersible surface decorated magnetic formulation was developed for pH-responsive controlled release of chemotherapeutic drug and efficient heating source for hyperthermia therapy. [ABSTRACT FROM AUTHOR]

• Iron carbide (Fe 5 C 2) nanoparticles show ferromagnetic properties with high saturation magnetization. • Fe 5 C 2 nanoparticles reveal an extended optical absorption property. • We have demonstrated Fe 5 C 2 nanoparticles as a hyperthermia heat probe with dual magneto-photo-thermal therapeutic features. • Fe 5 C 2 nanoparticles suspension displays enhanced SAR values relative to that of Fe 3 O 4 nanoparticles. Localized heat generation using nanoparticles is a promising supplementary technique to the well-established cancer treatments, such as chemotherapy and radiotherapy. Here, we demonstrate that iron carbide (Fe 5 C 2) nanoparticles with a thin carbon shell have the collective magnetothermal and photothermal effects based on the ferromagnetic and photonic properties. When the Fe 5 C 2 nanoparticle suspension is irradiated with a NIR laser (808 nm), it yields unprecedented heating effects. Further, owing to the observed high magnetization and coercivity, the Fe 5 C 2 nanoparticle suspension on exposure to an alternating magnetic field (ACMF) exhibits an enhanced specific absorption rate (SAR) as compared to Fe 3 O 4 nanoparticles of the same size. This significant improvement in the SAR arises from the cooperative contribution from the hysteresis and susceptibility losses. This work also gives quantitative information about the ACMF effects on heating ability as well as provides some guidelines for obtaining enhanced heating activity in nanoparticle suspensions of a given magnetic material. [ABSTRACT FROM AUTHOR]

Abstract: Superparamagnetic nanocomposite particles prepared by the ultrasonic spray pyrolysis were used in localized hyperthermia therapy, one of the many therapy options for cancer treatment. The primary particle size of the Fe2O3/MgO nanocomposite particles prepared at 800°C was approximately 10nm. The particles show superparamagnetic properties with a blocking temperature of −148°C. Heat generated by an alternating magnetic field of 60Oe increases the tissue temperature to 42.5°C after 125s. [Copyright &y& Elsevier]

• Polyaspartamide (PA)-encapsulated SPIONs as nano-heaters for hyperthermia therapy. • Enhancing biocompatibility and cellular uptake due to biotin functional group. • Effective cancer killing in both in vitro and in vivo hyperthermia experiments. • These results will open further potential for cancer treatment in the future. We report a delicate synthesis process of polyaspartamide-encapsulated superparamagnetic iron oxide nanoparticles (PA-encapsulated SPIONs) with their sufficiently obtained grain-size below 100 nm for hyperthermia application. Iron oxide nanoparticles with a high magnetization have been applied as nano-heaters while polyaspartamide (PA) is a biocompatible and biodegradable polymer with a polysuccinimide (PSI) backbone. Multi-functional polymer PA could be conjugated with other groups such as biotin to enhance the uptake capability by receptors of cancer cells. Consequently, encapsulating SPIONs nano-heaters with PA biopolymer is an attractive roadmap for hyperthermia therapy application. Our results revealed that PA-encapsulated SPIONs showed excellent biocompatible behavior based on cell viability test. With Prussian blue staining of cancer cells (4T1), cellular uptake of PA-encapsulated SPIONs was significantly increased in the presence of biotin conjugated on the outer shell. Furthermore, PA-encapsulated SPIONs exhibited effective cancer killing activities in both in vitro and in vivo hyperthermia experiments. Therefore, PA-encapsulated SPIONs might have potential for hyperthermia therapy. [ABSTRACT FROM AUTHOR]