Search

Ferroptosis, a form of iron-dependent, lipid peroxidation-driven cell death, has been extensively investigated in recent years, and several studies have suggested that the ferroptosis-inducing properties of iron-containing nanomaterials could be harnessed for cancer treatment. Here we evaluated the potential cytotoxicity of iron oxide nanoparticles, with and without cobalt functionalization (Fe2O3 and Fe2O3@Co-PEG), using an established, ferroptosis-sensitive fibrosarcoma cell line (HT1080) and a normal fibroblast cell line (BJ). In addition, we evaluated poly (ethylene glycol) (PEG)-poly(lactic-co-glycolic acid) (PLGA)-coated iron oxide nanoparticles (Fe3O4-PEG-PLGA). Our results showed that all the nanoparticles tested were essentially non-cytotoxic at concentrations up to 100 μg/mL. However, when the cells were exposed to higher concentrations (200–400 μg/mL), cell death with features of ferroptosis was observed, and this was more pronounced for the Co-functionalized nanoparticles. Furthermore, evidence was provided that the cell death triggered by the nanoparticles was autophagy-dependent. Taken together, the exposure to high concentrations of polymer-coated iron oxide nanoparticles triggers ferroptosis in susceptible human cancer cells. [ABSTRACT FROM AUTHOR]

Tuning the fundamental properties of iron oxide magnetic nanoparticles (MNPs) according to the required biomedical application is an unsolved challenge, as the MNPs' properties are affected by their composition, their size, the synthesis process, and so on. In this work, we studied the effect of zinc and manganese doping on the magnetic and structural properties of MNPs synthesized by the microwave-assisted polyol process, using diethylene glycol (DEG) and tetraethylene glycol (TEG) as polyols. The detailed morpho-structural and magnetic characterization showed a correspondence between the higher amounts of Mn and smaller crystal sizes of the MNPs. Such size reduction was compensated by an increase in the global magnetic moment so that it resulted in an increase of the saturation magnetization. Saturation magnetization M S values up to 91.5 emu/g and NMR transverse relaxivities r 2 of 294 s − 1 mM − 1 were obtained for Zn and Mn- doped ferrites having diameters around 10 nm, whereas Zn ferrites with diameters around 15 nm reached values of M S ∼ 97.2 emu/g and of r 2 ∼ 467 s − 1 mM − 1 , respectively. Both kinds of nanoparticles were synthesized by a simple, reproducible, and more sustainable method that makes them very interesting for diagnostic applications as MRI contrast agents. [ABSTRACT FROM AUTHOR]

Background: Coronaviruses usually cause mild respiratory disease in humans but as seen recently, some human coronaviruses can cause more severe diseases, such as the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the global spread of which has resulted in the ongoing coronavirus pandemic. Results: In this study we analyzed the potential of using iron oxide nanoparticles (IONPs) coated with biocompatible molecules like dimercaptosuccinic acid (DMSA), 3-aminopropyl triethoxysilane (APS) or carboxydextran (FeraSpin™ R), as well as iron oxyhydroxide nanoparticles (IOHNPs) coated with sucrose (Venofer®), or iron salts (ferric ammonium citrate -FAC), to treat and/or prevent SARS-CoV-2 infection. At non-cytotoxic doses, IONPs and IOHNPs impaired virus replication and transcription, and the production of infectious viruses in vitro, either when the cells were treated prior to or after infection, although with different efficiencies. Moreover, our data suggest that SARS-CoV-2 infection affects the expression of genes involved in cellular iron metabolism. Furthermore, the treatment of cells with IONPs and IOHNPs affects oxidative stress and iron metabolism to different extents, likely influencing virus replication and production. Interestingly, some of the nanoparticles used in this work have already been approved for their use in humans as anti-anemic treatments, such as the IOHNP Venofer®, and as contrast agents for magnetic resonance imaging in small animals like mice, such as the FeraSpin™ R IONP. Conclusions: Therefore, our results suggest that IONPs and IOHNPs may be repurposed to be used as prophylactic or therapeutic treatments in order to combat SARS-CoV-2 infection. [ABSTRACT FROM AUTHOR]

Advanced oxidation processes constitute a promising alternative for the treatment of wastewater containing organic pollutants. Still, the lack of cost-effective processes has hampered the widespread use of these methodologies. Iron oxide magnetic nanoparticles stand as a great alternative since they can be engineered by different reproducible and scalable methods. The present study consists of the synthesis of single-core and multicore magnetic iron oxide nanoparticles by the microwave-assisted polyol method and their use as self-heating catalysts for the degradation of an anionic (acid orange 8) and a cationic dye (methylene blue). Decolorization of these dyes was successfully improved by subjecting the catalyst to an alternating magnetic field (AMF, 16 kA/m, 200 kHz). The sudden temperature increase at the surface of the catalyst led to an intensification of 10% in the decolorization yields using 1 g/L of catalyst, 0.3 M H2O2 and 500 ppm of dye. Full decolorization was achieved at 90 °C, but iron leaching (40 ppm) was detected at this temperature leading to a homogeneous Fenton process. Multicore nanoparticles showed higher degradation rates and 100% efficiencies in four reusability cycles under the AMF. The improvement of this process with AMF is a step forward into more sustainable remediation techniques. [ABSTRACT FROM AUTHOR]

[Display omitted] • Iron oxide nanoflowers (NFs) were synthesized at gram-scale by the polyol method. • The scaled synthesis of NFs exhibited a 91 % mean reproducibility. • Magnetic harvesting of microplastics (MPs) led to a removal capacity of 1000 mg/g NF. • NFs-catalyzed MPs degradation yielded up to 80% mineralization. • NFs-magnetic induction heating improved MPs degradation reaction. Addressing the ecological risks and human health threats posed by emerging contaminants requires the development of reproducible and scalable materials and technologies. In this context, the performance of multicore flower-shaped nanoparticles (NFs) with approximately 40 nm diameters was assessed for extracting and degrading polyethylene microplastics from cosmetics in water samples. These NFs, exhibiting cooperative magnetic behavior and high magnetic moment per particle, were scaled to grams of product in a larger reactor (1 L), yielding a 91 % mean reproducibility for structural, colloidal and magnetic properties. The NFs were directly attached to microplastic surfaces via ultrasonic treatment and separated using a permanent magnet, demonstrating removal capacities of up to 1000 mg MP /g NF under optimal conditions (pH 7, 10 mg NFs, 30 min, field strength 320 kA/m). Subsequently, microplastics in aqueous suspensions were hydrolyzed at 150 °C followed by mineralization through a Fenton-like reaction catalyzed by the NFs where reactive oxygen species produced, in the presence of H 2 O 2 , break the organic molecules. Mineralization yields ranged from 20 % to 75 % at 25 and 90 °C, respectively, with a further increase to 78 % achieved under an alternating magnetic field (60 mT, 100 kHz), obviating the need for high temperatures. These results highlight the potential of NFs and associated technologies in effectively addressing the challenges associated with emerging contaminants, offering promising avenues for environmental remediation and human health protection. [ABSTRACT FROM AUTHOR]