A protective effect of CeO2 nanoparticles on human serum albumin (HSA) under nitrosative stress induced by peroxynitrite (ONOO–) was demonstrated. The effect of nanodisperse CeO2 and ONOO– on the tryptophan fluorescence of purified HSA, as well as albumin isolated from biological fluids, blood plasma, peritoneal (ascitic), and synovial (joint) fluids, was examined for the first time by fluorescence spectroscopy. ONOO– decreased the intrinsic fluorescence of HSA, whereas preliminary incubation of the protein with a CeO2 sol markedly attenuated this effect. In the presence of nanodisperse CeO2, the degree of oxidative modification of albumin induced by ONOO– decreased by 20

Background: Nanoceria exhibits unique catalytic activity toward reactive oxygen species (ROS), mimicking the functions of natural enzymes-a property that underlies its biomedical applications, given the essential role of ROS in living organisms. Carnosine is a pH buffer with intrinsic antioxidant properties; it chelates metals and binds carbonyl compounds. Objective(s): Using human embryonic lung fibroblast model, this study investigates the impacts of carnosine-conjugated nanoscale CeO2 on cell survival, cellular oxidative status, ROS-induced DNA oxidation, dual-strand DNA breaks, activation of DNA repair response, and gene and protein expression of NOX4, NRF2, STAT3, as well as proliferation and autophagy markers. Results: Carnosine-conjugated nanoceria proved to be non-cytotoxic at millimolar concentrations. Its effects on cytotoxicity, genotoxicity, DNA repair, mitochondrial membrane potential, autophagy, and NOX4 and NRF2 expression were similar to those of bare nanoceria. The principal differences were observed in the expression of STAT3, PCNA, and BCL2 proteins, where carnosine-coated nanoceria induced a pronounced activating impact after 24 h of exposure, thus promoting proliferation and increasing concentration of the PCNA proliferation marker. Conclusion: We hypothesize that carnosine-coated nanoceria directly activates the STAT3/BCL2 axis. These findings may facilitate the development of new molecular models for studying signaling pathways and advance in characterization of the nanoceria's biochemical roles in regulating ROS-driven cellular pathways. Moreover, carnosine-coated nanoceria could be considered a potential agent for enhancing the survival of cell cultures-such as hematopoietic cultures intended for activation of the STAT3/BCL2 axis.

A series of novel diboron-capped ruthenium(II) hexachloroclathrochelates were prepared via the template condensation of three molecules of dichloroglyoxime, as a chelating ligand synthon, with various aromatic boronic acids, as Lewis-acidic capping agents, on a ruthenium(II) ion as a matrix. The use of two equivalents of para-tolylboronic acid in the presence of the cyclooctadiene-acetonitrile ruthenium(II) complex with a tetrafluoroborate counter ion unexpectedly afforded an unique macrobicyclic product with two non-equivalent boron-based apical fragments. Reactive diarylboron-capped ruthenium(II) cage complexes with equivalent cross-linking groups were prepared in moderate yields starting from the acetonitrile ruthenium(II) complex with iodine counter anions. The same initial compound was used for preparation of the chemically robust tert-butylphenylboron-capped ruthenium(II) hexachloroclathrochelate. Its postsynthetic ribbed functionalization with a phenanthrenyl-containing primary amine, as a functionalizing N-nucleophilic agent, afforded the target diphenanthrenyl-terminated ruthenium(II) diaminoclathrochelate. The obtained novel cage 4d-metallocomplexes were characterized using elemental analysis, HR MALDI-TOF mass spectrometry, 1H and 13C{1H} NMR spectroscopy, UV-vis spectroscopy, and single-crystal X-ray diffraction analysis. Their 3D-shaped ruthenium(II)-centered molecules possess intermediate trigonal prismatic-trigonal antiprismatic geometries; their Ru-N distances are relatively short (approximately 2.0 Å). High physisorption of the designed diphenanthrenyl-terminated ruthenium(II) clathrochelate on the surfaces of activated carbon, reduced graphene oxide and carbon paper was found using UV-vis spectrophotometry. The redox characteristics of the prepared complexes and their electrocatalytic activities in the hydrogen evolution reaction (HER) were studied in homogeneous dichloromethane solutions using CV and DPV techniques. Electrochemically generated ruthenium(I)-centered cage complexes are the most probable catalytically active intermediates in this clathrochelate-electrocatalyzed redox reaction. Testing their HER electrocatalytic activity in homogeneous solutions after the addition of H+ ions allowed one to observe the corresponding catalytic waves. In the case of an immobilized ruthenium-based clathrochelate electrocatalyst for the HER, the consumption of this platinum group metal is very low due to the formation of monolayers on the surface of the cathode materials.

A comparative study of the redox behaviour of nanocrystalline isostructural ACe 2 (PO 4 ) 3 (A = NH + 4 , K + , Rb + ) double ceric phosphates was performed. It has been established that with respect to alkylperoxyl radicals or hydrogen peroxide as reactive oxygen species, all the double ceric phosphates acted as antioxidants or prooxidants, respectively. The antioxidant activity towards alkylperoxyl radicals was found to be the higher for the phosphates containing potassium or rubidium. Notably, for KCe 2 (PO 4 ) 3 and RbCe 2 (PO 4 ) 3 an inverse dependence of catalytic activity on concentration in the reaction with H 2 O 2 was found, in contrast to NH 4 Ce 2 (PO 4 ) 3 . The redox behaviour of nanoscale cerium dioxide used for comparison was similar to that of ammonium ceric phosphate, but significantly lower in absolute values. This was explained by the suppressive effect of phosphate anions presented in the buffer solutions.

In the original publication [...].

The product of interaction of cerium tetrafluoride complex [CeF4(dmso)2] with Ph2POOH in dmso was studied in solid state and in solution. The isolated powder compound of the composition CeF2(Ph2POO)2. dmso was characterized by chemical and XRD analysis, 19F{1H}and 31P{1H} NMR and IR spectroscopy. The mother liquor above the precipitate was studied by 19F{1H} and 31P{1H} NMR spectroscopy. Quantum chemical calculations of possible structures of the complex [F3 & Scy;& iecy;(& micro;-Ph2PO2)3 & Scy;& iecy;(& micro;-Ph2PO2)3 & Scy;& iecy;F3] and cis-and trans-isomers [& Scy;& iecy;F2(Ph2PO2)2], corresponding to the composition CeF2(Ph2POO)2. dmso were carried out and it was obtained that the formation of a trinuclear complex is energetically more preferable. Direct evidence of the trinuclear structure was obtained by studying the equilibrium in an equimolar mixture of CeF4(dmso)2 + 2Ph2POOH and HfF4(dmso)2 + 2Ph2POOH solutions by 19F{1H} NMR. The values of metal-fluorine and metal-oxygen interatomic distances in the [F3 & Mcy;(mu-Ph2PO2)3 & Mcy;(mu-Ph2PO2)3MF3] (M = Ce, Ti, Zr) complexes are discussed.

In the original publication [...].

Malonate ligands demonstrate versatility for intercalating metal complexes into layered rare-earth hydroxides (LREHs), enabling controlled tuning of coordination geometry and composition. As a proof of concept, a series of copper(II) malonate complexes with various substituents was synthesized and successfully intercalated into layered yttrium, europium, or terbium hydroxide at room temperature via anion-exchange reactions. The copper content in these hybrid materials increased in the order: butylmalonate < benzylmalonate < cyclopropanedicarboxylate < dimethylmalonate. To further expand the range of accessible metal malonate complexes, dimethyl- and benzylmalonate anions were intercalated into layered yttrium hydroxide for the first time and subsequently metalated in situ, yielding well-defined Cu2+ species within the interlayer space without disrupting the host lattice. Density functional theory (DFT) calculations provided insight into the structural arrangements of the copper complexes in the interlayer galleries. Comprehensive characterization of the resulting materials by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), IR, UV-vis, and electron paramagnetic resonance (EPR) spectroscopy confirmed both the successful formation of hybrid structures and elucidated the coordination environment of the intercalated copper species.

The photocatalytic degradation of plastic waste represents a pivotal strategy for mitigating the global plastic pollution and fostering resource-efficient utilization. Herein, a facile impregnation method was used to uniformly load various Ni-substituted polyoxometalates (Ni-POMs) onto CdS nanospheres and thus obtain a series of single-cluster Ni-POM@CdS photocatalysts. During visible-light irradiation for 10 h, the catalyst with the highest synergistic photoredox performance (Ni-9@CdS-10) achieved an exceptional extent of polylactic acid degradation and H-2 productivity (22.29 mmol center dot g(cat)(-1)) exceeding that of pristine CdS similar to 160-fold. The generation of pyruvate-a versatile and valuable chemical-as a degradation product (19.01 mmol center dot g(cat)(-1)) rendered the process highly economically viable. Systematic control experiments and comprehensive characterization analyses indicate that the photocatalytic degradation of plastic waste by Ni-9@CdS-10 proceeds via a charge transfer-mediated mechanism, with the Ni-9 clusters acting as electron sponges and efficiently extracting photogenerated electrons from CdS to promote H-2 evolution while facilitating hole-dominated plastic oxidation. This work provides valuable insights into the development of plastic waste degradation processes promoted by Ni-POM photocatalysts and establishes a practical strategy for converting plastic waste into fuels and chemicals.

In the original publication [...].

Results are presented from studying physicochemical characteristics and radiosensitizing properties of a new type of lutetium fluoride (LuF3) nanoparticle as a promising nanoradiosensitizer for X-ray irradiation of B16/F10 melanoma cells. A comprehensive analysis is performed of functional characteristics of synthesized LuF3 nanoparticles, their cytotoxicity, and their radiosensitizing effect in vitro. It is shown that LuF3 nanoparticles have a hydrodynamic diameter of less than 200 nm. Colloidal sol obtained on their basis is highly stable as a result of using the biocompatible stabilizer ammonium citrate. LuF3 nanoparticles have a cytotoxic and radiosensitizing effect on melanoma cells in concentrations of 116 mg/mL and higher by reducing their metabolic activity and membrane mitochondrial potential while initiating apoptosis. Such nanomaterial can form the basis of promising modern approaches to increasing the effectiveness of radiation therapy.

This study investigated the redox properties of cerium oxide nanoparticles (CeO2 NPs) and their conjugates with superoxide dismutase (SOD) or horseradish peroxidase (HRP) as well as the UV-induced modulation of these properties. UV exposure non-monotonically decreased the SOD-like property of the bare CeO2 NPs. The CeO2 conjugates with enzymes were analyzed both immediately after preparation and after being aged for 3 h. Chemiluminescence assays showed the synergistic effect for the CeO2-SOD conjugates which showed high SOD activity. Additionally, CeO2 NPs enhanced the stability of the conjugated SOD under UV exposure thus demonstrating a photoprotective function. The CeO2-HRP conjugates demonstrated lower prooxidant activity compared to the bare enzyme, however higher stability under UV irradiation. The effect of UV radiation on CeO2-HRP conjugates was found to be multidirectional and depended on the incubation time of the CeO2 NPs with the enzyme. The results demonstrated that CeO2-enzyme conjugates offer tunable dual functionality and UV light could be an important parameter affecting their redox properties. The latter effect should be taken into account for designing advanced cosmeceutical formulations.

The unique redox properties of nanoscale cerium dioxide determine its diverse application in biology and medicine as a regulator of oxidative metabolism. Lipid modifiers of the nanoparticle surface change their biochemical properties and bioavailability. Complexes with lipids can be formed upon contact of the nanoparticles with the membrane. The effects of lipid coating on nanoceria have not been studied yet. Here, we assessed the effect of bare and cardiolipin-coated CeO2 on the expression of oxidative metabolism genes in human embryonic lung fibroblasts. Cell viability, mitochondrial activity, intracellular reactive oxygen species, NOX4, NRF2, and NF-κB expression, oxidative DNA damage/repair, autophagy, and cell proliferation were studied. We used an MTT assay, fluorescence microscopy, real-time reverse transcription polymerase chain reaction, and flow cytometry. At a concentration of 1.5 μM, bare and cardiolipin-coated nanoceria penetrated into cells within 1–3 h. Cell survival, mitochondrial activity, and the proliferative effect were similar for bare and cardiolipin-coated nanoceria. Intracellular ROS, activation of NOX4, NRF2, and NF-kB, DNA oxidative damage, and DNA break/repair were different. Cardiolipin-coated nanoceria induced intracellular oxidative stress and short-term activation of these genes and DNA damage/break/repair. Unlike bare nanoceria, cardiolipin-coated nanoceria induced autophagy. Thus, the effects of cardiolipin-coated nanoceria are determined by both the nanoceria itself and cardiolipin. Presumably, the differences in properties are due to lipid peroxidation of cardiolipin. This effect needs to be taken into account when developing nanoceria-based drugs targeting mitochondria.

The development of advanced wound dressings that integrate favorable physico-mechanical properties with the ability to support physiological healing processes remains a critical challenge in biomaterials science. An ideal dressing should modulate the wound microenvironment, prevent infection, maintain hydration, and possess adequate strength and elasticity. This study aimed to fabricate and characterize electrospun chitosan (CS)-based 3D scaffolds dual-reinforced with halloysite nanotubes (HNTs) and cerium oxide nanoparticles (CeONPs) to enhance material properties and biological performance. HNTs were incorporated to improve electrospinnability and provide mechanical reinforcement, while CeONPs were added for their redox-modulating and anti-inflammatory activities. Composite mats were fabricated via non-capillary electrospinning. The individual and synergistic effects of HNTs and CeONPs were systematically evaluated using physico-chemical methods (SEM, EDX, WAXS, TGA, mechanical testing) and biological assays (in vitro cytocompatibility with mesenchymal stem cells, in vivo biocompatibility, and wound healing efficacy in a rat model). Scaffolds containing only HNTs exhibited defect-free nanofibers with an average diameter of 151 nm, whereas the dual-filler (CS-PEO-HNT-CeONP) composites showed less uniform fibers with a rough surface and a larger average diameter of 233 nm. The dual-filler system demonstrated significantly enhanced mechanical properties, with a Young’s modulus nearly double that of pure CS mats (881 MPa vs. 455 MPa), attributed to strong interfacial interactions. In vivo, the CS-PEO-HNT-CeONP scaffolds degraded more slowly, promoted earlier formation of a connective tissue capsule, and elicited a reduced inflammatory response compared to single-filler systems. Although epithelialization was temporarily delayed, the dual-filler composite ultimately facilitated superior tissue regeneration, characterized by a more organized, native-like collagen architecture. The synergistic combination of HNTs and CeONPs within a CS matrix yields a highly promising scaffold for wound management, offering a unique blend of tailored biodegradability, enhanced mechanical strength, and the ability to guide healing towards a regenerative rather than a fibrotic outcome, particularly for burns and traumatic injuries.

Nanoceria exhibits unique catalytic properties towards reactive oxygen species (ROS), which act as mediators of key signaling pathways. Albumin is the most abundant blood protein, and its interaction with nanoceria modifies the properties of both nanoceria and albumin. Using an in vitro model of human embryonic lung fibroblasts, we investigated biochemical properties of nanoceria–albumin conjugates towards cell viability, intracellular reactive oxygen species, expression of NOX4, NRF2, and NF-κB, oxidative DNA damage/repair, apoptosis, cell proliferation, and autophagy. The results demonstrate that albumin binding alters the physicochemical properties of nanoceria, promoting efficient cellular uptake through modulation of surface interactions. This conjugation attenuates nanoceria’s influence on intracellular reactive oxygen species equilibrium and mitochondrial membrane potential by modifying nanoparticle-protein interfacial dynamics. Notably, albumin-bound nanoceria induces a stronger activation of NOX4, resulting in increased genotoxic stress; however, the enhanced activation of DNA repair pathways mitigates this damage more efficiently than bare nanoceria. Furthermore, albumin-to-nanoceria conjugation modulates signaling pathways by enhancing suppression of the pro-inflammatory NF-κB cascade and stimulating autophagic processes. Overall, the physicochemical effects of nanoceria modification due to albumin conjugation reduce cytotoxicity of nanoceria while augmenting its anti-inflammatory and regenerative potential.

Nanoceria is a multifaceted enzyme-like catalyst of ROS-mediated (reactive oxygen species) reactions, which results in its multiple biomedical applications. Biodegradable polysaccharide coatings improve biocompatibility, while the effects of these coatings on the ROS-related activity of nanoceria in cells need thorough studies. Here, we used human embryonic lung fibroblasts to study the effects of maltodextrin and chitosan coatings on cellular oxidative metabolism of nanoceria by examining cell viability, mitochondrial potential, accumulation of nanoparticles in cells, intracellular ROS, expression of NOX4 (NADPH oxidase 4), NRF2 (nuclear factor erythroid 2-related factor 2), NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells), and STAT3 (signal transducer and activator of transcription 3) proteins as well as the expression of biomarkers of DNA damage/repair, cell proliferation, and autophagy. Both types of polysaccharide-coated nanoceria were non-toxic up to millimolar concentrations. For maltodextrin-coated nano-CeO2, in contrast to bare nanoparticles, there was no oxidative DNA damage/repair with moderate activation of NOX4 expression. Like bare nanoceria, maltodextrin-coated nanoparticles demonstrate the proliferative impact and do not activate autophagy. However, maltodextrin-coated nanoparticles have an activating impact on mitochondrial potential and the NF-κB pathway. Chitosan-coated nanoceria causes short-term intracellular oxidative stress, activation of the expression of NOX4, STAT3, and NRF2, oxidative DNA damage, and double-strand breaks accompanied by activation of DNA repair systems. In contrast to maltodextrin-coated nanoparticles, chitosan-coated nanoceria inhibits the NF-κB pathway and activates autophagy. These findings would be useful in the development of advanced nanoceria-based pharmaceuticals and contribute to the understanding of the biochemical properties of nanoceria as a modulator of ROS-dependent signaling pathways.

The UV-shielding composite films based on nanocrystalline cellulose (CNC) modified with both CeO2 and WO3 nanoparticles were prepared by solvent casting method. In the composites, both CeO2 and WO3 nanoparticles showed redox activity under UV-irradiation, and the joint effects of that metal oxides in the composite films were evidenced. The WO3 nanoparticles provided reversible photochromic properties to the WO3/CNC film under UV-irradiation while CeO2 nanoparticles inhibited the photochromic effect. The mechanism of this inhibition in the CeO2/WO3/CNC films was investigated using UV–vis and FTIR spectroscopy. The photodegradation of CNC catalyzed by CeO2 nanoparticles inherent in CeO2/CNC films was prevented by the addition of WO3 nanoparticles. The CeO2/CNC and CeO2/WO3/CNC films exhibited strong UV-shielding property. The synthesized photostable UV-shielding CeO2/WO3/CNC films with photochromic property which can easily be tuned by the CeO2 to WO3 ratio can be useful for various applications, including protection of UV-sensitive dyes and production of UV-shielding packages.

The relevance of the investigation is related to the study of the storage possibility of natural gas in a hydrated state in subpermafrost aquifers in the territory of Yakutia. This paper presents the results of a study of the gas composition in natural gas hydrates obtained in moist porous media and, for comparison, considers the processes of hydrate formation in a volume of water. Bi- and polydisperse quartz sands were used as a model of porous medium. Moisture content was set with distilled water and was 15%. Hydrates were obtained in high-pressure chambers at a temperature of +5°C and a pressure of 8 MPa. The fat content coefficients of gases in hydrates and their kinetic stability at atmospheric pressure and temperature +5°C were determined. It has been established that the coefficients of fat content of gases in the resulting hydrates are almost the same and the gases are classified as fatty. However, the stability of hydrates obtained in bulk water is three times less than that of hydrates in a porous medium, which indicates the stability of the latter.