Polyoxometalate inhibition of SOX2-mediated tamoxifen resistance in breast cancer.

BACKGROUND: Increased cancer stem cell (CSC) content and SOX2 overexpression are common features in the development of resistance to therapy in hormone-dependent breast cancer, which remains an important clinical challenge. SOX2 has potential as biomarker of resistance to treatment and as therapeutic target, but targeting transcription factors is also challenging. Here, we examine the potential inhibitory effect of different polyoxometalate (POM) derivatives on SOX2 transcription factor in tamoxifen-resistant breast cancer cells. METHODS: Various POM derivatives were synthesised and characterised by infrared spectra, powder X-ray diffraction pattern and nuclear magnetic resonance spectroscopy. Estrogen receptor (ER) positive breast cancer cells, and their counterparts, which have developed resistance to the hormone therapy tamoxifen, were treated with POMs and their consequences assessed by gel retardation and chromatin immunoprecipitation to determine SOX2 binding to DNA. Effects on proliferation, migration, invasion and tumorigenicity were monitored and quantified using microscopy, clone formation, transwell, wound healing assays, flow cytometry and in vivo chick chorioallantoic membrane (CAM) models. Generation of lentiviral stable gene silencing and gene knock-out using CRISPR-Cas9 genome editing were applied to validate the inhibitory effects of the selected POM. Cancer stem cell subpopulations were quantified by mammosphere formation assays, ALDEFLUOR activity and CD44/CD24 stainings. Flow cytometry and western blotting were used to measure reactive oxygen species (ROS) and apoptosis. RESULTS: POMs blocked in vitro binding activity of endogenous SOX2. [P2W18O62]6- (PW) Wells-Dawson-type anion was the most effective at inhibiting proliferation in various cell line models of tamoxifen resistance. 10 µM PW also reduced cancer cell migration and invasion, as well as SNAI2 expression levels. Treatment of tamoxifen-resistant cells with PW impaired tumour formation by reducing CSC content, in a SOX2-dependent manner, which led to stem cell depletion in vivo. Mechanistically, PW induced formation of reactive oxygen species (ROS) and inhibited Bcl-2, leading to the death of tamoxifen-resistant cells. PW-treated tamoxifen-resistant cells showed restored sensitivity to tamoxifen. CONCLUSIONS: Together, these observations highlight the potential use of PW as a SOX2 inhibitor and the therapeutic relevance of targeting SOX2 to treat tamoxifen-resistant breast cancer.

Construction of Molecularly Dispersed Polyoxometalate-Alumina Hybrid Hollow Nanoflowers via Water-Induced Kirkendall Effect.

Hybrid nanomaterials with controllable structures and diverting components have attracted significant interest in the functional materials field. Here, we develop a solvent evaporation-induced self-assembly (EISA) strategy to synthesize nanosheet-assembled phosphomolybdic acid (H3PMo)-alumina hybrid hollow spheres. The resulting nanoflowers display a high surface area (up to 697 m2 g-1), adjustable diameter, high chemical/thermal stability, and especially molecularly dispersed H3PMo species. By employing various microscopic and spectroscopic techniques, the formation mechanism is elucidated, revealing the simultaneous control of the morphology by heteropoly acids and water through the water-induced Kirkendall effect. The versatility of the synthesis method is demonstrated by varying surfactants, heteropoly acids, and metal oxide precursors for the facile synthesis of hybrid metal oxides. Spherical hybrid alumina serves as an attractive support material for constructing metal-acid bifunctional catalysts owing to its advantageous surface area, acidity, and mesoporous microenvironment. Pt-loaded hollow flowers exhibit excellent catalytic performance and exceptional stability in the hydrodeoxygenation of vanillin with recyclability for up to 10 cycles. This research presents an innovative strategy for the controllable synthesis of hybrid metal oxide nanospheres and hollow nanoflowers, providing a multifunctional platform for diverse applications.

Lindqvist-type Polyoxometalates Act as Anti-breast Cancer Drugs via Mitophagy-induced Apoptosis.

OBJECTIVE: Lindqvist-type polyoxometalates (POMs) exhibit potential antitumor activities. This study aimed to examine the effects of Lindqvist-type POMs against breast cancer and the underlying mechanism. METHODS: Using different cancer cell lines, the present study evaluated the antitumor activities of POM analogues that were modified at the body skeleton based on molybdenum-vanadium-centered negative oxygen ion polycondensations with different side strains. Cell colony formation assay, autophagy detection, mitochondrial observation, qRT-PCR, Western blotting, and animal model were used to evaluate the antitumor activities of POMs against breast cancer cells and the related mechanism. RESULTS: MO-4, a Lindqvist-type POM linking a proline at its side strain, was selected for subsequent experiments due to its low half maximal inhibitory concentration in the inhibition of proliferation of breast cancer cells. It was found that MO-4 induced the apoptosis of multiple types of breast cancer cells. Mechanistically, MO-4 activated intracellular mitophagy by elevating mitochondrial reactive oxygen species (ROS) levels and resulting in apoptosis. In vivo, breast tumor growth and distant metastasis were significantly reduced following MO-4 treatment. CONCLUSION: Collectively, the results of the present study demonstrated that the novel Lindqvist-type POM MO-4 may exhibit potential in the treatment of breast cancer.

"Bowling Collision Effect" of CoMo6 Polyoxometalate Units Enables Wide Temperature Range from -20 to 60 °C and Dendrite Mitigation Li-S Batteries.

To improve the performance of Lithium-Sulfur (Li-S) batteries, the reaction catalysts of lithium polysulfides (LiPSs) reactions should have the characteristics of large surface area, efficient atomic utilization, high conductivity, small size, good stability, and strong adjustability. Herein, Anderson-type polyoxometalate ([TMMo6O24]n-, TM = Co, Ni, Fe, represented by TMMo6 POMs) are used as the modified materials for Li-S battery separator. By customizing the central metal atoms, this work gains insights into the layer-by-layer electron transfer mechanism between TMMo6 units and LiPSs, similar to the collision effect of a bowling ball. Theoretical analysis and in situ experimental characterization show that the changes of CoMo6 units with moderate binding energy and lowest Gibbs free energy result in the formation of robust polar bonds and prolonged S─S bonds after adsorption. Hence, the representative Li-S battery with CoMo6 and graphene composite modified separator has a high initial capacity of 1588.6 mA h g-1 at 0.2 C, excellent cycle performance of more than 3000 cycles at 5 C, and uniform Li+ transport over 1900 h. More importantly, this work has revealed the inherent contradiction between the kinetics and thermodynamics, achieving a stable cycle in the temperature range of -20 to 60 °C.

Redox-active polyoxovanadates as cofactors in the development of functional protein assemblies.

The interactions of polyoxovanadates (POVs) with proteins have increasingly attracted interest in recent years due to their potential biomedical applications. This is especially the case because of their redox and catalytic properties, which make them interesting for developing artificial metalloenzymes. Organic-inorganic hybrid hexavanadates in particular offer several advantages over all-inorganic POVs. However, they have been scarcely investigated in biological systems even though, as shown in this work, hybrid hexavanadates are highly stable in aqueous solutions up to relatively high pH. Therefore, a novel bis-biotinylated hexavanadate was synthesized and shown to selectively interact with two biotin-binding proteins, avidin and streptavidin. Bridging interactions between multiple proteins led to their self-assembly into supramolecular bio-inorganic hybrid systems that have potential as artificial enzymes with the hexavanadate core as a redox-active cofactor. Moreover, the structure and charge of the hexavanadate core were determined to enhance the binding affinity and slightly alter the secondary structure of the proteins, which affected the size and speed of formation of the assemblies. Hence, tuning the polyoxometalate (POM) core of hybrid POMs (HPOMs) with protein-binding ligands has been demonstrated to be a potential strategy for controlling the self-assembly process while also enabling the formation of novel POM-based biomaterials that could be of interest in biomedicine.

Upscaling Brønsted acid intercalation and exfoliation of graphite into graphene by polyoxometalate clusters for sodium-ion battery application.

Non-oxidative intercalation of graphite avoids damage to graphene lattices and is a suitable method to produce high-quality graphene. However, the yield of exfoliated graphene is low in this process due to the poor delamination efficiency of guest species. In this study, a Brønsted acid intercalation protocol is developed involving polyoxometalate (POM) clusters (H6P2W18O62) as guests and intercalation of graphite is realized at the sub-nanometer scale. Theoretical simulation based on DFT elucidates the stepwise intercalation mechanism of Brønsted acid molecules and clusters. Unlike common molecules/ionic guests, intercalation of POM clusters induces large expansion and extensive donor-acceptor interactions among graphite interlayers. This significantly weakens the van der Waals forces and promotes exfoliation efficiency of graphene layers. The exfoliated graphene possesses outstanding features of large lateral size, thin thickness, and high purity, and shows excellent performance as the anode for high power sodium-ion batteries. This work proffers a new pathway toward non-oxidative intercalation of graphite for large-scale production of graphene.

Recent Advances on the Functionalities of Polyoxometalate-Based Ionic Liquids.

Polyoxometalate (POM)-based ionic liquids (POM-ILs) are gaining increasing attention due to their diverse structures and functionalities. POMs in POM-ILs not only act as essential structural building blocks but also play a crucial role in their functional performance. With the incorporation of POMs, POM-ILs find applications in various fields such as chemical catalysis, energy science, materials science, sensors, and more. The abundant availability of POMs and other building blocks in POM-ILs, along with their versatile combination possibilities, present promising opportunities for the future. Rather than focusing solely on discovering new structures of POM-ILs, current developments in this field emphasize exploring their functions, leading to the emergence of numerous new applications. Summarizing these advancements aids in understanding the latest trends and facilitates rapid evolution. This review examines the recent five years' worth of results to analyze the new functions of POM-ILs, categorizing them based on their unique characteristics.

Unprecedented Organogermanium Functionalized GeIV-SbIII-Templating Polyoxotungstate Nanocluster for Photothermal-Chemodynamic Cancer Therapy.

The function-oriented synthesis of polyoxometalate (POM) nanoclusters has become an increasingly important area of research. Herein, the well-known broad-spectrum anticancer drug Ge-132 which contains GeIV as potential heteroatoms and carboxyl coordination sites, is introduced to the POM system, leading to the first organogermanium functionalized GeIV-SbIII-templating POM nanocluster Na4[H2N(CH3)2]16 H18[Sm4(H2O)12W4O14Ge(CH2CH2COOH)]2[SbW9O33]4[Ge(CH2CH2COOH) SbW15O54]2·62H2O (1). An unprecedented organogermanium templating Dawson-like [Ge(CH2CH2COOH)SbW15O54]12- building block is discovered. To take advantage of the potential pharmaceutical activity of such an organogermanium-functionalized POM cluster, 1 is further composited with gold nanoparticles (NPs) to prepare 1-Au NPs, which doubles the blood circulation time of 1-based nanodrug. Efficient separation of photogenerated charges in 1-Au NPs largely boosts the photothermal conversion efficiency (PCE = 55.0%), which is nearly 2.1 times that of either single 1 (PCE = 26.7%) or Au NPs (PCE = 26.2%), and simultaneously facilitate the generation of toxic activate reactive oxygen species in tumor microenvironment. Based on these findings, it is demonstrated that 1-Au NPs are a multifunctional and renal clearable nanomedicine with great potential in photoacoustic imaging guiding photothermal-chemodynamic therapy for breast cancer.

Polyoxometalates: metallodrug agents for combating amyloid aggregation.

Alzheimer's disease (AD) is a devastating neurodegenerative disease that affects ∼50 million people globally. The accumulation of amyloid-ß (Aß) plaques, a predominant pathological feature of AD, plays a crucial role in AD pathogenesis. In this respect, Aß has been regarded as a highly promising therapeutic target for AD treatment. Polyoxometalates (POMs) are a novel class of metallodrugs being developed as modulators of Aß aggregation, owing to their negative charge, polarity, and three-dimensional structure. Unlike traditional discrete inorganic complexes, POMs contain tens to hundreds of metal atoms, showcasing remarkable tunability and diversity in nuclearities, sizes, and shapes. The easily adjustable and structurally variable nature of POMs allows for their favorable interactions with Aß. This mini-review presents a balanced overview of recent progress in using POMs to mitigate amyloidosis. Clear correlations between anti-amyloid activities and structural features of POMs are also elaborated in detail. Finally, we discuss the current challenges and future prospects of POMs in combating AD.

Polyoxometalate-based iron-organic complex nanozymes with peroxidase-like activities for colorimetric detection of hydrogen peroxide and ascorbic acid.

As a new type of artificial enzyme, a nanozyme is an ideal substitute for natural enzymes and has been successfully applied in many fields. However, in the application of biomolecular detection, most nanozymes have the disadvantages of long reaction times or high detection limits, prompting researchers to search for new efficient nanozymes. In this work, the enzyme-like activities of three polyoxometalate-based iron-organic complexes ([Fe(bpp)2](Mo6O19), [Fe(bpp)2]2(Mo8O26)·2CH3OH, and [Fe(bpp)2]4H[Na(Mo8O26)]3), namely, FeMo6, Fe2Mo8, and Fe4Mo8Na, were analyzed. All three polyoxometalate-based iron-organic complexes were found to be capable of catalyzing hydrogen peroxide (H2O2) to oxidize 3,3',5,5'-tetramethylbenzidine and o-phenylenediamine, resulting in visible color changes, further exhibiting peroxidase-like activity. Results showed that Fe4Mo8Na had more active sites due to its long chain structure, endowing more prominent peroxidase-like activity compared with Fe2Mo8 and FeMo6. A colorimetric sensing platform for H2O2 and ascorbic acid detection based on Fe4Mo8Na was established. The linear response range for H2O2 detection was 0.5-100 µM, and the detection limit was 0.143 µM. The linear response for ascorbic acid detection ranges from 0 to 750 µM with a detection limit of 1.07 µM. This study provides a new perspective for developing new nanozymes and expanding the sensing and detection application of nanozymes.

Vacancy-Rich SnO2 Quantum Dot Stabilized by Polyoxomolybdate as Electrocatalyst for Selective NH3 Production.

The pronounced conductivity of tin dioxide (SnO2) nanoparticles makes it an ideal multifunctional electrode material, while the challenge is to stabilize the quantum dot (QD) SnO2 nanocore in water. An Anderson-type polyoxomolybdate, (NH4)6[Mo7O24], is employed as an inorganic ligand to stabilize a ca. 6 nm SnO2 QD (Mox@SnO2). X-ray scattering and diffraction studies confirm the tetragonal SnO2 nanocore in Mox@SnO2. Elemental analyses are in good agreement with the mass spectrometric detection of the [Mo7O24]6- cluster present in Mox@SnO2. The ionic POMs attached to the SnO2 surface through [Mo-O-Sn] covalent linkages have been established by surface zeta potential, shift of the [Mo = O]t Raman vibration, and extended X-ray absorption fine structure (EXAFS) analyses. The presence of the [Mo7O24]6- cluster in the Mox@SnO2 is responsible for the remarkable aqueous stability of Mox@SnO2 in the pH range of 3-9. Dominant oxygen vacancy in the SnO2 core, identified by EXAFS data and the anisotropic electron paramagnetic resonance (EPR) signals (g ∼ 2.4 and 1.9), results in facile electronic conduction in Mox@SnO2 while being deposited on the electrode surface. Mox@SnO2 acts as an active catalyst for the electrocatalytic nitrate reduction (eNOR) to ammonia with 94% faradaic efficiency (FE) at -0.2 V vs RHE and a yield rate of 28.9 mg h-1 cm-2. The stability of Mox@SnO2 in acidic pH provides scope to reuse the Mox@SnO2 electrode at least four times with notable NH3 selectivity and a superior production rate (239.06 mmol g-1(cat) h-1). This study demonstrates the essential role of POM in stabilizing SnO2 QD, harnessing its electrochemical activity toward electrocatalytic ammonia production.

Modulation of electronic structure of Ni3S2 via Fe and Mo co-doping to enhance the bifunctional electrocatalytic activities for HER and OER.

Heazlewoodite nickel sulfide (Ni3S2) is advocated as a promising nonnoble catalyst for electrochemical water splitting because of its unique structure configuration and high conductivity. However, the low active sites and strong sulfur-hydrogen bonds (S-Hads) formed on Ni3S2 surface greatly inhibit the desorption of Hads and reduce the hydrogen and oxygen evolution reaction (HER and OER) activity. Doping is a valid strategy to stimulate the intrinsic catalytic activity of pristine Ni3S2 via modifying the active site. Herein, the Ni foam supported Fe and Mo co-doped Ni3S2 electrocatalysts (Fe-MoS2/Ni3S2@NF) have been constructed using Keplerate polyoxomolybdate {Mo72F30} as precursor through a facile hydrothermal process. Experimental results certificate that Fe and Mo co-doping can effectively tune the local electronic structure, facilitate the interfacial electron transfer, and improve the intrinsic activity. Consequently, the Fe-MoS2/Ni3S2@NF display more excellent HER and OER activity than MoS2/Ni3S2@NF and bare Ni3S2@NF by delivering the 10 and 50 mA cm-2 current densities at ultra-low overpotentials of 74/175 and 80/160 mV for HER and OER. Moreover, when coupled in an alkaline electrolyzer, Fe-MoS2/Ni3S2@NF approached the current of 10 mA cm-2 under a cell voltage of 1.60 V and exhibit excellent stability. The strategy to realize tunable catalytic behaviors via foreign metal doping provides a new avenue to optimize the water splitting catalysts.

Polyoxometalate functionalized magnetic metal-organic framework with multi-affinity sites for efficient enrichment of phosphopeptides.

The reasonable design of metal-organic framework (MOF)-derived nanomaterial has important meaning in increasing the enrichment efficiency in the study of protein phosphorylation. In this work, a polyoxometalate (POM) functionalized magnetic MOF nanomaterial (Fe3O4@MIL-125-POM) was designed and fabricated. The nanomaterial with multi-affinity sites (unsaturated metal sites and metal oxide clusters) was used for the enrichment of phosphopeptides. Fe3O4@MIL-125-POM had high-efficient enrichment performance towards phosphopeptides (selectivity, a mass ratio of bovine serum albumin/α-casein/ß-casein at 5000:1:1; sensitivity, 0.1 fmol; satisfactory repeatability, ten times). Furthermore, Fe3O4@MIL-125-POM was employed to enrich phosphopeptides from non-fat milk digests, saliva, serum, and A549 cell lysate. The enrichment results illustrated the great potential of Fe3O4@MIL-125-POM for efficient identification of low-abundance phosphopeptides.

Photocatalyzed Cascade Hydrogen Atom Transfers for Assembly of Multi-Substituted α-SCF3 and α-SCF2H Cyclopentanones.

A photocatalyzed formal (3+2) cycloaddition has been developed to construct original polysubstituted α-SCF3 cyclopentanones in a regio- and diastereoselective manner. This building block approach leverages trifluoromethylthio alkynes and branched/linear aldehydes, as readily available reaction partners, in consecutive hydrogen atom transfers and C-C bond formations. Difluoromethylthio alkynes are also compatible substrates. Furthermore, the potential for telescoped reaction starting from alcohols instead of aldehydes was demonstrated, as well as process automatization and scale-up under continuous microflow conditions. This prompted density functional theory (DFT) calculations to support a radical-mediated cascade process.

Enhanced Electrical Conductivity of Polyoxometalates by Bridging with Mixed-Valent Multinuclear Platinum Complexes.

Polyoxometalates (POMs) are nanosized molecular metal oxide anion clusters with tuneable structures and functionalities, and they exhibit a redox chemistry and catalytic activity in multielectron redox processes. These are typically poor electrical conductors (<10-10 Scm-1), which is attributed to negligible electronic interactions among anions in the solid state. Since the reduced electrons on the d0 metals in POMs are delocalized, electrical conductivity was improved when judicious pathways for the electrons were created by bridging the POMs. Utilized with the electronic interactions between bridging oxygen atoms with the highest occupied molecular orbital in the POMs and the metal dz2 orbitals in the multinuclear platinum complexes, and three mixed-valent assemblies were synthesized and characterized. Simply mixing Keggin-type or Dawson-type POMs with tetranuclear or trinuclear platinum complexes in solution afforded three single crystals, and all three compounds were paramagnetic with mixed oxidation states and better conductivities at room temperature than the parent compounds.

Sustainable depolymerization of lignin into aromatic compounds using amphiphilic Anderson-type polyoxometalate catalysts.

Lignin serves as a primary abundant source of renewable aromatic compounds. Achieving efficient breakdown of lignin and retaining its aromatic properties is highly desirable but remains a challenging task. To address this challenge, we synthesized Anderson-type polyoxometalate (POM) catalysts, particularly [CTAC]2[CoMo6]. We then investigated the effectiveness of the POM catalysts in the oxidative depolymerization of larch lignin. Under conditions of 160 °C, 1.0 MPa oxygen atmosphere, and a catalyst-to-substrate ratio of 1:5, we achieved a monomer yield of phenolic compounds at 12.43 wt%. The unsaturated coordination sites of Mo5+ within the catalysts were identified as active sites, facilitating enhanced O2 adsorption and activation. The enhanced O2 adsorption significantly influenced the production of aromatic monomers from lignin. We observed that the catalysts effectively cleaved CC bonds in ß-O-4 dimer compounds using lignin dimer model compounds. Notably, the [CTAC]2[CoMo6] catalyst exhibited excellent stability across five cycles, maintaining its high efficiency in lignin depolymerization. This indicates that Anderson-type POM-based catalysts exhibit potential for sustainable conversion of biomass into valuable compounds and for enhancing lignin valorization processes.

Polyoxometalate-Polymer Directed Macromolecular Architectonics of Silver Nanoparticles as Effective Antimicrobials.

A novel inorganic-organic-inorganic ternary bioactive material formulated on antimicrobial peptide-based polymer has been reported. Supramolecular approach has been employed to incorporate molecularly crowded tyrosine-based polymer stabilized silver nanoparticles into membrane bound vesicles exploiting polyoxometalate-triggered surface templating strategy. Utilizing the covalent reversible addition fragmentation chain transfer (RAFT) polymerization and exploiting templated supramolecular architectonics at biopolymer interface, the bioactive ternary polymeric nanohybrids have been designed against Shigellosis leveraging the antibacterial activities of silver nanoparticle, cationic amphiphilic tyrosine polymer and inorganic polyoxometalate. The detail investigation against Shigella flexneri 2a cell line demonstrates that the collaborative mechanism of the ternary hybrid composite enhances the bactericidal activity in comparison to only polyoxometalate and polymer stabilized silver nanoparticle with an altered mechanism of action which is established via detailed biological analysis.

Role of Metal-Organic Framework Topology on Thermodynamics of Polyoxometalate Encapsulation.

Polyoxometalates (POMs) are discrete anionic clusters whose rich redox properties, strong BroÌ·nsted acidity, and high availability of active sites make them potent catalysts for oxidation reactions. Metal-organic frameworks (MOFs) have emerged as tunable, porous platforms to immobilize POMs, thus increasing their solution stability and catalytic activity. While POM@MOF composite materials have been widely used for a variety of applications, little is known about the thermodynamics of the encapsulation process. Here, we utilize an up-and-coming technique in the field of heterogeneous materials, isothermal titration calorimetry (ITC), to obtain full thermodynamic profiles (ΔH, ΔS, ΔG, and Ka) of POM binding. Six different 8-connected hexanuclear Zr-MOFs were investigated to determine the impact of MOF topology (csq, scu, and the) on POM encapsulation thermodynamics.

Single Dispersion of Fe(H2O)2-Based Polyoxometalate on Polymeric Carbon Nitride for Biomimetic CH4 Photooxidation.

Direct methane conversion to value-added oxygenates under mild conditions with in-depth mechanism investigation has attracted wide interest. Inspired by methane monooxygenase, the K9Na2Fe(H2O)2{[γ-SiW9O34Fe(H2O)]}2·25H2O polyoxometalate (Fe-POM) with well-defined Fe(H2O)2 sites is synthesized to clarify the key role of Fe species and their microenvironment toward CH4 photooxidation. The Fe-POM can efficiently drive the conversion of CH4 to HCOOH with a yield of 1570.0 µmol gPOM -1 and 95.8% selectivity at ambient conditions, much superior to that of [Fe(H2O)SiW11O39]5- with Fe(H2O) active site, [Fe2SiW10O38(OH)]2 14- and [P8W48O184Fe16(OH)28(H2O)4]20- with multinuclear Fe-OH-Fe active sites. Single-dispersion of Fe-POM on polymeric carbon nitride (PCN) is facilely achieved to provide single-cluster functionalized PCN with well-defined Fe(H2O)2 site, the HCOOH yield can be improved to 5981.3 µmol gPOM -1. Systemic investigations demonstrate that the (WO)4-Fe(H2O)2 can supply Fe═O active center for C-H activation via forming (WO)4-Fea-Ot···CH4 intermediate, similar to that for CH4 oxidation in the monooxygenase. This work highlights a promising and facile strategy for single dispersion of ≈1-2 Å metal center with precise coordination microenvironment by uniformly anchoring nanoscale molecular clusters, which provides a well-defined model for in-depth mechanism research.

New magnetic nanocomposites based on hexafrite and keggin-type -type heteropolyanions: Synthesized and characterized for removal of environmental pollutants.

This research paper details the creation of innovative nanocomposites using the sol-gel technique, incorporating polyoxometalates SiW9Ba3 to stabilize ceramic particles of strontium ferrite (SrFe12O19) polymer and Chitosan (CS). The identification and confirmation of the nanocomposites obtained at each stage were carried out through the use of FT-IR, EDX, XRD, and FESEM analyses. To evaluate their ability to remove organic dyes, we analyzed the catalytic activity of these nanocomposites during photocatalytic detoxification procedures. With its exceptional photocatalytic properties, the nanocomposite (SiW9Ba3@SrFe12O19@Cs) was able to remove estamipride poison at an impressive rate of 85 % and xylene dye solution at an even higher rate of 98 %. In addition, an extensive examination was undertaken to explore the primary variables that influence process efficiency. The study suggests that ceramic nanocomposites incorporating heteropolyoxometalate may offer a viable approach to effectively eradicate pollutants from the environment.