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Breast cancer is one of the deadliest cancers for women, so cell labeling and therapy of breast cancer become imperative. In this work, dextran- and carboxymethyl dextran–coated Fe3O4 nanoparticles (Fe3O4@DEX and Fe3O4@CMD) were well synthesized through the co-precipitation method. The dextran and carboxymethyl dextran coating reduces the average particle size of Fe3O4 nanoparticles from 10.9 to 4.0–5.5 nm, and the coated samples exhibit average hydrodynamic diameters ranging from 31 to 110 nm. The coating promotes the dispersibility of nanoparticles. Saturation magnetization is reduced from 60.3 to 5.6–7.1 emu/g in the coated MNPs due to the large weight ratio of the coating layer and the decrease in particle size. Hemolysis and cytotoxicity assay results indicate the excellent biocompatibility of Fe3O4 nanoparticles. The cellular uptake assay confirms that both dextran- and carboxymethyl dextran–coated Fe3O4 nanoparticles are easily taken in by breast cancer cells. Comprehensively considering dispersion, biocompatibility, and cellular uptake, the Fe3O4@CMD is more suitable for application in the bio-labeling of breast cancer cells. The SAR values of the Fe3O4@DEX and Fe3O4@CMD range from 19.2 to 30.7 W/g. The SAR value is mainly influenced by the hydrodynamic diameter in the coated samples. The Fe3O4@CMD20 shows the maximum SAR value of 30.7 W/g and has potential application in magnetic hyperthermia therapy. [ABSTRACT FROM AUTHOR]

Chemodynamic therapy (CDT) is a novel tumor treatment method by using hydroxyl radicals (•OH) to kill cancer cells. However, its therapeutic effects are strictly confined by the short lifespan of •OH and reduced •OH generation speed. Herein, an effective CDT is achieved by both improving •OH lifetime and long‐lasting generating •OH through intraparticle electron transfer within heterogeneous nanoparticles (NPs). These heterogeneous NPs are composed of evenly distributed Cu and Fe3O4 (CFO NPs) with large interaction interfaces, and electrons tend to transfer from Cu to Fe3O4 for the appearance of ≡Cu2+ and increase in ≡Fe2+. The generated ≡Cu2+ can interact with GSH, which prolongs the lifespan of •OH, produces ≡Cu+ for higher speed •OH generation with H2O2, and induces cell ferroptosis for tumor therapy. The improved ≡Fe2+ can also improve the •OH release under H2O2 until Cu is depleted. As a result, a sustainable •OH generation is achieved to promote cell apoptosis for effective tumor therapy. Since H2O2 and GSH are only overexpressed at tumor, and CFO NPs can degrade in the tumor microenvironment, these NPs are with high biosafety and can be metabolized by urine. This work provides a novel biomaterial for effective cancer CDT through intraparticle electron transfer. [ABSTRACT FROM AUTHOR]

To maintain a comfortable indoor living environment in low latitude or tropical regions, humans consume significant amounts of electrical energy in air conditioning, leading to substantial CO2 emissions. Passive daytime radiative cooling (PDRC) allows objects to cool down during the daytime without any energy consumption by dissipating heat through the atmospheric transparency window (8−13 µm) to outer space, which has garnered significant attention. However, the practical applications of common PDRC materials are hindered by their poor optical selectivity and high‐reflective silver backing. Additionally, the availability of artificial photon emitters with complex structures and excellent performance is also limited by their high cost. Herein, a novel multilayer prismatic photonic metamaterial film without any silver reflector, easily scalable and produced by a roll‐to‐roll method is demonstrated, which exhibits ≈96.4% sunlight reflectance (0.3−2.5 µm) and ≈97.2% emissivity in mid‐infrared (IR) (8−13 µm). At an average solar intensity of ≈920 W m−2, it is on average 6.8 °C below ambient temperature during the day and theoretically yields a radiative cooling power of 88.9 W m−2. Furthermore, the film exhibits excellent hydrophobicity, superior flexibility, and robust mechanical strength, providing an attractive and viable pathway for practical applications addressing the pressing challenges of climate and energy issues. [ABSTRACT FROM AUTHOR]

In ceramic injection molding, the conventional solvent‐debinding process encounters limitations such as solvent cost and environmental pollution. In this paper, a suitable thermal‐debinding process from room temperature to 250°C using carbon/alumina embedding powders with nano and submicron size was developed to remove the soluble binders replacing the conventional solvent debinding of injection molding ZrO2 ceramic. The effects of the embedding powders on microstructure and debinding ratio were studied in detail. The results showed that the main factor influencing debinding ratio was associated with the sufficient dispersing of mixed particles, which was characterized by the relative change ratio of tap volume. A debinding mechanism was proposed to explain the effects of carbon/alumina mixed powders on the debinding ratio and surface cracks. Based on the influencing mechanism, the debinded green part with the elimination of soluble binders and optimal surface was achieved using the mixed powders with C/A = 8/2 on the top and C/A = 4/6 on the bottom. [ABSTRACT FROM AUTHOR]

Enlightened by the great success of the drug repurposing strategy in the pharmaceutical industry, in the current study, material repurposing is proposed where the performance of carbonyl iron powder (CIP), a nutritional intervention agent of iron supplement approved by the US FDA for iron deficiency anemia in clinic, was explored in anti-cancer treatment. Besides the abnormal iron metabolic characteristics of tumors, serving as potential targets for CIP-based cancer therapy under the repurposing paradigm, the efficacy of CIP as a catalyst in the Fenton reaction, activator for dihydroartemisinin (DHA), thus increasing the chemo-sensitivity of tumors, as well as a potent agent for NIR-II photothermal therapy (PTT) was fully evaluated in an injectable alginate hydrogel form. The CIP-ALG gel caused a rapid temperature rise in the tumor site under NIR-II laser irradiation, leading to complete ablation in the primary tumor. Further, this photothermal-ablation led to the significant release of ATP, and in the bilateral tumor model, both primary tumor ablation and inhibition of secondary tumor were observed simultaneously under the synergistic tumor treatment of nutritional-photothermal therapy (NT/PTT). Thus, material repurposing was confirmed by our pioneering trial and CIP-ALG-meditated NT/PTT/immunotherapy provides a new choice for safe and efficient tumor therapy. [ABSTRACT FROM AUTHOR]

Self‐monitoring in tumor therapy is a concept that allows for real‐time monitoring of the location and state of applied nanomaterials. This monitoring relies on dynamic signals, such as wave or magnetic signals, which vary in response to changes in the location and state of nanomaterials. Dynamic changes in nanomaterials can be monitored using dynamic signals, making it possible to determine and control the treatment process. Theranostic nanomaterials, which possess unique physical and chemical properties, have recently been explored as a viable option for self‐monitoring. With the help of self‐monitoring, theranostic nanomaterials can guide themselves to achieve region‐selective treatment with higher controllability and safety. In this review, self‐monitoring theranostic nanomaterials will be introduced in three parts according to their roles during therapy: tumor accumulation, tumor therapy, and metabolism. The limitations and future challenges of current self‐monitoring theranostic nanomaterials will also be discussed. [ABSTRACT FROM AUTHOR]

This document is an editorial for a special issue of the journal "Materials" that focuses on "Soft Magnetic Materials and Their Applications." Soft magnetic materials are easily magnetized and demagnetized within magnetic fields and are used in electronics, energy conversion, and information processing. The special issue presents the latest advancements in the synthesis, characterization, and applications of soft magnetic materials, including soft ferrites, alloys, and composites. The papers cover topics such as improving high-frequency properties of soft ferrites, developing FeCo thin films for high-frequency electronic devices, and measuring and characterizing soft magnetic materials. The document discusses the applications of soft magnetic materials in electrical machines, motors, magnetic shielding structures, and atomic sensors. Various studies on the magnetic properties and performance of different soft magnetic materials are presented, suggesting their potential for enhancing the efficiency, sensitivity, and precision of electrical machines and sensors. The document concludes by acknowledging the authors and funding support for the research. [Extracted from the article]

To meet the needs for higher energy efficiency and a wide operating temperature range of electric vehicles, the low‐loss MnZn ferrites in a wide temperature range have been developed by optimizing the Fe content and the oxygen partial pressure (PO2) during the sintering process in this work. For the optimal sample, power loss at 300 kHz/100mT is 204 kW/m3 at 25°C and remains below 290 kW/m3 in the wide temperature range from ‐10 to 120°C. The loss separation method was employed to clarify the effects of the Fe content and PO2 on power loss. The equivalent circuit model has been employed to fit the complex impedance and it is found that the increase of PO2 enhances both the grain resistance Rg and the grain boundary resistance Rgb. The enhancement of Rgb is mainly responsible for the reduction of eddy current loss and consequently power loss. Dielectric permittivity is as large as about 15000 in this series of samples due to the electric polarization at the rich grain boundaries. Dielectric loss is very low between ‐50 and 150°C and has little contribution to the energy loss. [ABSTRACT FROM AUTHOR]

Calcium-overload-mediated tumor therapy has received considerable interest in oncology. However, its efficacy has been proven to be inadequate due to insufficient calcium ion concentration at the tumor site coupled with challenges in facilitating efficient calcium uptake by tumors, leading to unsatisfactory therapeutic outcomes. In the present study, calcium carbonate nanoshell mineralized ferric polydopamine nanoparticles (Fe-PDA@CaCO 3 NPs) were prepared for achieving Ca 2+ -overload-mediated tumor therapy. Upon entering the tumor site, the pH-responsive CaCO 3 layer, acting as a "Ca 2+ storage pool", rapidly degraded and released high quantities of free Ca 2+ within the weakly acidic environment. The Fe-PDA core, with its excellent photothermal conversion properties, could significantly increase the temperature upon exposure to near-infrared (NIR) light irradiation, thereby activating the TRPV1 channel and leading to a large influx of released Ca 2+ into the cytoplasm. Furthermore, the exposed Fe-PDA core could react with the tumor-overexpressed hydrogen peroxide (H 2 O 2 ) to efficiently produce hydroxyl radicals (•OH), significantly increasing intracellular reactive oxygen species (ROS) levels and thus inhibiting the activity of the Ca 2+ efflux pump, resulting in a high intracellular Ca 2+ concentration. Ultimately, the increase in calcium/ROS levels could disrupt mitochondrial homeostasis and activate the apoptosis pathway. The current work presents a promising approach for tumor therapy using photothermal-enhanced calcium-overload-mediated ion interference therapy and chemodynamic therapy.