Journal of Cluster Science最新文献

Reactions of the anti-alcohol drug disulfiram (tetraethylthiuram disulphide = Et₄TDS) with low valent triosmium complexes are described. Room temperature reaction with [Os₃(CO)₁₀(MeCN)₂], affords three new open polynuclear clusters, [Os₃(CO)₁₀(S₂CNEt₂)₂] (1), [Os₄(CO)₁₂{µ₃-η¹(C),κ²(O,O)-CO₂}(S₂CNEt₂)(µ-S₂CNEt₂)] (2) and [Os₃(CO)₉(µ₃-SCNEt₂){µ-SC(O)NEt₂}] (3) together with the known mononuclear complex cis-[Os(CO)₂(S₂CNEt₂)₂] (4). All result from oxidative-addition of disulfiram to the triosmium centre, with 2 also capturing CO₂, while cluster 3 has undergone further C–S bond scission and partial oxidation of one of the generated thiocarboxamide ligands. With [Os₃(CO)₁₀(µ-H)₂], complexes 1 and 4 are also formed along with previously reported [Os₃(CO)₁₀(µ-S₂CNEt₂)(µ-H)] (5), [Os₃(CO)₉(µ₃-S₂CNEt₂)(µ-H)] (6), and the new cluster, [Os₃(CO)₉(µ-S₂CNEt₂)(µ-H)] (8), which is an isomer of 6. The product distribution is rationalized by completing pathways following the oxidative-addition of disulfiram. Thus, reductive-elimination of H₂ affords 1, which in turn converts to 4, while reductive-elimination of the (unstable) dithiocarbamic acid, Et₂NCS₂H, leads to the formation of 5, which can further lose CO to afford isomers 6 and 8. Heating disulfiram with [Os₃(CO)₁₂] at 110 °C predominantly affords 4, together with smaller amounts of the novel trithiocarbamate complex, cis-[Os(CO)₂(S₂CNEt₂)(S₃CNEt₂)] (9). All the compounds have been characterized by elemental analysis, IR and ¹H NMR spectroscopy, together with single crystal X-ray diffraction analysis of six molecules.

Biofilms are group of bacteria that are protected by a slimy layer. These biofilms are more resistant to antibiotics than individual bacteria which are the basic building blocks of biofilms. Researchers are actively introducing new treatments that are supposed to be more efficient in fighting biofilms and to be less toxic to the patient than the conventional antibiotics. Here in this study we propose the development of Fusidic acid (FA) loaded liposomes and niosomes to improve the anti-bacterial activity in-vitro against Staphylococcus aureus strains. The designed niosomes and liposomes of FA were smaller in size ranging from 116.4 to 274.2 nm displaying homogeneity in terms of size distribution with PdI (le 0.4) 0 and zeta potential ranging from (pm) 20 to (pm) 60 mV. The nanoparticles were stable for 30 days irrespective of the storage condition, 4 °C and Room temperature. SEM analysis confirmed spherical type nanoparticles and diameter of the nanoparticles were complementary with DLS (NanoZetaSizer) results. All types of nanoparticles showed higher entrapment of FA, particularly FA-Span-40 NPs showed %EE of 94%, rest of the nanoparticle showed %EE (ge) 85%. The niosomal and liposomal formulations of FA modified the biological behavior of the drug and provided better in vitro performance against S. aureus compared to the standard (FA). Span-40, Tween-20 and cationic liposomes MIC value (0.039–0.078 µg/mL) were effective and comparable with standard, FA (0.04 µg/mL). Furthermore, the effectiveness of antibacterial agents at a microscopic scale was carried out using AFM after contact of all the formulations with Staphylococcus aureus strains. Greater change in the structural and mechanical properties of bacterial cells was observed for FA loaded tween-20 niosomes, and cationic liposomes compared to control and standard FA showing efficacious antibacterial activity. The study demonstrates the designed nano formulations could be a useful strategy to enhance the efficacy of antimicrobials agents.

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This manuscript presents a simple method to obtaining a chitosan/PEO/NiFe₂O₄ composite with photocatalytic activity under sunlight for the Methyl Orange organic dye degradation. Such composite is made up of two polymers that form a matrix containing nickel ferrite nanoparticles, NiFe₂O₄. The polymeric matrix is made up of 70% chitosan and 30% polyethylene oxide (PEO). Due to its chemical structure and microstructure, each polymer provides specific properties to the chitosan/PEO/NiFe₂O₄ film. The PEO provides mechanical stability to the polymeric substrate and the chitosan provides catalytic properties for the removal of the organic dye. NiFe₂O₄ nanoparticles are a semiconductor oxide with photocatalytic activity in the range of the visible radiation (bandgap of 1.9 eV); therefore, the dye degradation occurs under sunlight. These NiFe₂O₄ nanoparticles (NP) are obtained with different NP average size (around 10, 12, and 19 nm). The effect of NiFe₂O₄ nanoparticles sizes on the properties of the composites, its thermal stability, and on the photocatalytic degradation of the organic dye is analyzed. The photocatalysis test is performed by introducing the chitosan/PEO/NiFe₂O₄ films into the methyl orange aqueous solution and irradiating them with sunlight for 1 h. The samples are characterized from the structural and morphological point of view, thermal stability, and percentage of photocatalytic degradation of the dye after 1 h of exposure to sunlight. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and ultraviolet-visible spectroscopy (UV-VIS) are used to carry out the study.

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Carbon nanotubes (CNTs) exhibit exceptional properties, making them invaluable across various industries. Chemical vapor deposition (CVD) is one of the most widely used methods for producing CNTs. This study investigates key factors such as temperature, pressure, and carbon source that influence CNT synthesis. By understanding and controlling these parameters, significant improvements in CNT growth can be achieved. However, CNT growth is influenced by multiple interrelated factors, which complicates the identification of optimal conditions for each individual factor. These variables often interact and are not independent. In this research, we provide a comprehensive review of the critical factors affecting CNT growth to aid researchers in achieving more successful CNT synthesis.

The green synthesis of nanoparticles represents an eco-friendly and sustainable alternative to conventional chemical and physical synthesis methods. This approach minimizes the use of hazardous chemicals and leverages biological resources, aligning with the principles of green chemistry. This study aimed to characterise the green synthesised ZnONPs and evaluate their antimicrobial and anti-inflammatory activities. ZnONPs were synthesised using Washingtonia filifera seed extract and characterised using Scanning Electron Microscopy (SEM), UV–Vis spectroscopy, Fourier Transform Infrared (FT-IR) spectroscopy, energy-dispersive spectroscopy (EDX), and X-ray diffraction (XRD). Their antimicrobial activity against bacteria and fungi, as well as their anti-inflammatory potency, were assessed. SEM data revealed that the ZnONPs, fabricated with palm seed extract metabolites, were spherical with an average size of 50 nm. FT-IR analysis identified varied absorption peaks related to the functional groups of the plant extract and nanoparticles. The antimicrobial activity was dose-dependent, with Staphylococcus aureus and Escherichia coli showing inhibition zones of 8.5 ± 0.7 mm and 11.8 ± 0.3 mm, respectively, at 500 µg/mL. Pseudomonas aeruginosa exhibited a notable inhibition zone of 20.4 ± 0.7 mm. The ZnONPs also inhibited fungal mycelium growth. The in vitro anti-inflammatory activity of ZnONPs showed a concentration-dependent increase, with an 89.15% inhibition of RBC haemolysis at 110 µg/mL. The green synthesised ZnONPs demonstrated significant antimicrobial activity against clinical pathogens and potent anti-inflammatory effects, suggesting that this eco-friendly method could be a promising strategy for developing versatile biomedical products.

The present investigation successfully synthesized a novel tantalum-based CuTaS₃/AgTaS₃ heterostructure using D-penicillamine as a sulfur source and investigated its hydrogen evolution capability using both photocatalytic and electrocatalytic methods. The structural and morphological features were examined using XRD, Raman, FT-IR, TEM and SEM with EDS analysis, respectively. The UV-DRS results ascertain the visible-light response and bandgap of the synthesized materials. Combining AgTaS₃ with CuTaS₃ reduced the recombination rate, as revealed by the photocurrent measurements of the materials. The photocatalytic hydrogen production for the as-synthesized materials was investigated by consuming Na₂S + Na₂SO₃ as a sacrificial reagent. The CuTaS₃ with 5% of the best AgTaS₃ loading gives off the most H₂ evolution rate, 1430 µmol/g, after 5 h of being exposed to visible light. Furthermore, the electrocatalytic measurements were performed to assess the CuTaS₃/AgTaS₃ heterostructure for water-splitting hydrogen evolution reactions (HER). The results displayed that the enhanced HER reactivity with lower overpotentials and Tafel slope when heterostructure was formed. The higher double-layer capacitance (C_dl) value shows how many more active sites were formed after AgTaS₃ was combined with CuTaS₃. These results confirmed that the CuTaS₃/AgTaS₃ heterostructure generated H₂ effectively in both electrocatalytic and photocatalytic processes. The present work may bring innovative perceptions for the advancement of tantalum-based sulfide materials for green hydrogen production.

Mixed manganese/cerium oxide/hydroxyapatite composites are emerging as innovative materials with significant biomedical potential due to their antibacterial properties and biocompatibility. In this study, we synthesized mixed Mn/Ce oxide/HA composites using an ultrasonic-assisted sol-gel method, exploring their structural and functional characteristics through comprehensive analyses. Advanced characterization techniques, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), X-ray absorption spectroscopy (XAS), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and nitrogen adsorption-desorption isotherms, revealed a composite with enhanced structural stability and porosity, optimized for antibacterial applications. XRD confirmed the integration of a fluorite-structured CeO₂ phase with hexagonal hydroxyapatite, while FT-IR and XANES analyses verified the presence of functional phosphate groups and mixed oxidation states (Ce³⁺/Ce⁴⁺, Mn²⁺/Mn³⁺/Mn⁴⁺), essential for antibacterial efficacy. SEM imaging displayed a unique flake-like morphology conducive to clustering, and EDS confirmed elemental composition. Notably, nitrogen sorption isotherms revealed a marked increase in surface area from 2 m²/g in pure HA to 11–16 m²/g in Mn/Ce oxide/HA, which may enhance bacterial interaction. Antibacterial assays demonstrated potent activity against Bacillus cereus (B. cereus), Staphylococcus aureus (S. aureus), Staphylococcus epidermidis (S. epidermidis), Escherichia coli (E. coli), and Salmonella typhi (S. typhi), linked to reactive oxygen species production and bacterial membrane disruption. This study highlights the robust structural and antibacterial features of Mn/Ce oxide/HA composites, advancing their suitability for biomedical applications, particularly in infection-resistant materials and bone grafts.

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Brain tumor is one of the deadliest types of cancer in the world. The basic necessity of brain tumor-targeted therapy is to reach and accumulate the required quantity in the tumor microenvironment while maintaining therapeutic efficacy. In this regard, the current study sought to create thymoquinone-encapsulated Eudragit L100-coated solid lipid nanoparticles (TQ-encapsulated E-SLNs) for the transport of loaded thymoquinone (TQ) to the brain. TQ-encapsulated E-SLNs were formulated using the oil-in-water microemulsion process, and their physicochemical properties were investigated. TQ encapsulation, loading capacity, and release behavior of E-SLNs were also investigated. In vivo biodistribution studies were conducted to assess TQ delivery and accumulation in several organs of female Wistar rats. The TQ-encapsulated E-SLNs were mostly spherical with a crystalline structure and extremely stable in the physiological buffer system. The highest content of TQ was released in pH 5.5 (78.215 ± 0.749%) at 22 h. The pharmacokinetics and biodistribution investigations revealed that released TQ from TQ-encapsulated E-SLNs after 48 h of administration accumulated 16.5 ± 1.5% in brain, 21.167 ± 1.041% in kidneys, 12.125 ± 0.781% in heart, 16.375 ± 1.317% in liver, 13.5 ± 1.8% in lungs, and 17.15 ± 1.5%. Later, molecular modeling studies revealed that TQ had a greater binding energy of -7.8 kcal/mol to EGFR. Thymoquinone binding energy was very close to the reference drug Temozolomide. Molecular dynamics simulation studies showed that the TQ-EGFR docked complex was extremely stable up to 100 ns. The findings showed that the fabricated TQ-encapsulated E-SLNs remained unchanging in circulation for up to five days. Therefore, E-SLNs fabrications show promise as a method for targeting brain malignancies across the BBB.

Scanning and transmission electron microscopy, powder X-ray diffraction and thermogravimetric analyses were used to study the dynamics of the sorption processes of ligand-free iron nanoparticles produced by highly efficient physical synthesis, namely, the molecular beam method. The structure, chemical and phase composition of Fe-NaCl condensates with different iron contents, crystallite dimensions (nanoparticles) and nanoparticle surface areas depending on the condensation temperature, which characterize the sorption capacity, primarily for moisture and oxygen, were studied. Finally, the gravimetric analysis method was used to investigate the kinetics of the relative change in the weight of porous Fe–NaCl condensates with different iron contents, depending on the condensation temperature. With increasing synthesis temperature, the nanoparticle size increases, and the specific surface area decreases. Therefore, by changing the size of the nanoparticles at the same volume, we can regulate the ratio of the nanoparticle surface to the nanoparticle volume, i.e., change the properties of the reaction surface and, in this way, the contribution of the excess surface energy to the total free energy of the system. The mass fraction of physically adsorbed and bound oxygen (moisture) correlates with the size (area, surface) of the nanoparticles.

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Sorption of oxygen and water by EB PVD ligand-free Fe@Fe₃O₄ nanoparticle in open matrix nanopore

This research presents the development of an innovative and eco-friendly composite material, Alginate-Coated Nano Iron Oxide-Graphene Oxide (Alg-Fe₃O₄@GO), designed to enhance the adsorption and photocatalytic degradation of cationic dyes in wastewater treatment. The composite combines the biocompatibility of alginate with the high surface area and photocatalytic properties of graphene oxide and nano iron oxide. A comprehensive evaluation of the Alg-Fe₃O₄@GO composite was conducted to assess its efficiency in removing Methylene Blue (MB) and Malachite Green (MG) from aqueous solutions. Characterization techniques, including X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Transmission Electron Microscopy (TEM), Brunauer-Emmett-Teller (BET) surface area analysis, and Thermogravimetric Analysis (TGA), confirmed its structural and functional properties. BET analysis indicated a significant surface area of 317.8 m²/g, suggesting substantial adsorption capacity. Adsorption experiments revealed a maximum capacity of 163.8 mg/g for MB, achieving a removal efficiency of 98.5%, and 107.5 mg/g for MG, with a removal efficiency of 90.8% after 240 min of contact time at an initial dye concentration of 100 mg/L for both dyes. Kinetic studies indicated that the adsorption followed the Pseudo-Second Order model (R² > 0.99 for both dyes), while equilibrium data fitted well with the Langmuir Isotherm Model, indicating monolayer adsorption. Thermodynamic analysis indicated that the adsorption process was endothermic, with enthalpy changes of ΔH° = +25.33 kJ/mol for MB and ΔH° = +20.83 kJ/mol for MG, alongside a spontaneous nature (ΔG° < 0). Photocatalytic tests under visible light showed dye degradation efficiencies of 85.0% for MB and 78.0% for MG within 120 min. The composite retained over 85% of its initial adsorption capacity after six regeneration cycles, underscoring its potential as a sustainable, high-performance material for wastewater treatment.