Journal of Cluster Science最新文献

Chronic wound management remains a significant clinical challenge due to persistent infections and delayed tissue regeneration. In this study, the development and the evaluation of polyhydroxyalkanoate-coated magnetic nanoparticles (PHA-MNPs) derived from the cyanobacterium Desmonostoc muscorum as a novel topical agent for wound healing. PHA was extracted from D. muscorum biomass at a yield of 0.56 ± 0.03 g per g dry cell weight and used to coat magnetite nanoparticles synthesized via co-precipitation. The resulting PHA-MNPs were characterized by TEM (mean diameter 18 ± 3 nm), DLS (zeta potential − 25 ± 2 mV), FTIR, GC-MS, and UV–Vis spectroscopy. Antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa was quantified by broth microdilution assays (MICs comparable to ampicillin). Antibiofilm efficacy was assessed in microtiter plate assays, and hemocompatibility by hemolysis testing (< 5% hemolysis at ≤ 200 µg/mL). Cytotoxicity toward human epidermoid carcinoma (A431) and skin fibroblast (HFB4) cells was determined by MTT assays. In vivo wound healing was evaluated in a Wistar rat excisional wound model. Animals received topical low-dose PHA-MNPs (50 mg/kg), high-dose PHA-MNPs (100 mg/kg), Iruxol^® (positive control), or no treatment for 16 days. Wound closure was measured photographically, and tissue samples underwent histopathological analysis. PHA-MNPs exhibited potent antibacterial and antibiofilm activities, selective cytotoxicity (IC₅₀ 45 µg/mL for A431 vs. >200 µg/mL for HFB4), and excellent hemocompatibility. Low-dose PHA-MNP treatment achieved 85 ± 5% wound closure, comparable to Iruxol^® (95 ± 3%) and superior to the high-dose group (60 ± 6%) and untreated controls. Histology confirmed complete epithelialization and robust collagen deposition in low-dose and Iruxol^® groups. PHA-MNPs produced from D. muscorum combine antimicrobial, antibiofilm, and regenerative properties with biocompatibility, representing a promising, sustainable nanobiomaterial for advanced wound care applications.

Nanostructured materials with tailored morphologies exhibit unique physicochemical properties, making them highly attractive for catalysis, sensing, and biomedical applications. In this study, Copper/Cuprous oxide Yolk-Shell Nanostructures (Cu/Cu₂O-YSN) were synthesized via an eco-friendly approach using Cocos nucifera inflorescence (CnI) extracts as a bio-reducing agent in Fehling’s solution. By tuning the redox environment following Le Chatelier’s principle, precise control over nucleation and growth was achieved, leading to well-defined yolk-shell architectures. Real-time UV-Vis spectral analysis monitored the evolution of Cu/Cu₂O-YSN. Characterization techniques (UV-Vis, p-XRD, FE-SEM & EDX, TEM, HR-TEM, and SAED) confirmed the biphasic architecture, comprising cubic Cu and Cu₂O domains, with metallic copper constituting approximately 52% of the material. Yolk-shell formation was driven by interfacial mechanisms such as the nano-Kirkendall effect, Ostwald ripening, and Cabrera-Mott oxidation. A highly negative ζ potential of -48.38 mV indicated excellent colloidal stability due to phytochemical surface functionalization. UV-Vis spectral analysis revealed distinct isosbestic points at 304 nm, 343 nm, and 431 nm, suggesting a two-step electron/proton transfer mechanism (DPPH^• → DPPH⁻ → DPPH-H) during radical scavenging, with antioxidant activity (IC₅₀ = 40.58 µg mL^-1). The Cu/Cu₂O-YSN also demonstrated broad spectrum antibacterial activity, showing high sensitivity toward Gram-positive strains and significant cytotoxicity against human liver cancer cells - HepG2 (IC₅₀ = 25 ± 0.5 µg mL^-1), comparable to doxorubicin. Apoptotic features including membrane blebbing, chromatin condensation, and nuclear fragmentation were confirmed by Acridine Orange (AO/EB) dual staining and 4′,6-diamidino-2-phenylindole (DAPI) imaging. These findings establish green synthesized Cu/Cu₂O-YSN as promising multifunctional nanomaterials for advanced biomedical applications.

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Silver nanoparticles (AgNPs) exhibit unique physicochemical and biological properties that enable a wide-range of applications in medicine, environmental remediation, and chemical sensing. While experimental methods have advanced our understanding of AgNPs, computer simulations have become indispensable for exploring nanoparticle behavior at the atomic scale. This review summarizes recent developments in computational modeling of AgNPs, including silver clusters, using density functional theory (DFT), time-dependent DFT (TDDFT), molecular dynamics (MD), molecular docking, and hybrid methods. Simulation studies elucidate nanoparticle formation, ligand adsorption, surface functionalization, and interactions with biological molecules and chemical environments. Functionalization strategies using plant-derived compounds, peptides, pharmaceutical drugs, ionic liquids, and small organic molecules are critically discussed in relation to nanoparticle stability, surface properties, and functional performance. Applications of coated AgNPs in sensing, antimicrobial treatment, drug delivery, catalysis, and composite material design are discussed, with an emphasis on how simulation-driven insights complement experimental findings. Finally, future directions highlight the growing role of multiscale modeling and biologically realistic simulations in advancing the rational design of AgNPs for biomedical and environmental applications.

This work reports the sustainable synthesis and design of multi-metal ferrite nanocomposites supported by activated carbon (AC) derived from banana stem waste for high-performance energy storage. The AC was obtained through potassium hydroxide (KOH) chemical activation followed by high-temperature carbonization, producing a large surface area of 2271 m²/g and an average pore size of 2.96 nm. Nickel ferrite (NiFe₂O₄), manganese–nickel ferrite (Mn-NiFe₂O₄), and copper–nickel ferrite (Cu-NiFe₂O₄) nanoparticles were synthesized and integrated into the AC matrix using a co-precipitation method. Structural and surface characterizations, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) surface area analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), confirmed the successful incorporation of ferrite phases with crystallite sizes between 20 and 28 nm while maintaining high porosity. Electrochemical testing through cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS) demonstrated improved capacitance, conductivity, and cycling efficiency. The Mn-NiFe₂O₄/AC (Mn-NFAC) composite delivered the best performance, achieving a specific capacitance of 482 F·g⁻¹ at 1.0 A/g and retaining 93.9% of its initial capacitance after 10,000 cycles, surpassing pristine AC and other ferrite composites. Nyquist analysis revealed a low charge-transfer resistance (Rct = 5.29 Ω) and faster ion diffusion. In a symmetric two-electrode configuration, Mn-NFAC reached an energy density of 45 Wh/kg at a power density of 450 W/kg, while maintaining 220 F·g⁻¹ at 3.0 A/g with a power density of 1350 W/kg. These superior properties arise from the synergistic effects of the Mn-based ternary ferrite structure and the tailored porous AC framework, which together provide both electric double-layer capacitance and pseudo capacitance.

In this study, a green eutectic phase change material (EPCM) based on a binary mixture of 1-tetradecanol and oxalic acid was synthesized and characterized. This EPCM, demonstrates promising potential as a green and sustainable candidate for low to medium temperature thermal energy storage (TES) applications. To enhance the thermal properties of the synthesized EPCM, hexagonal boron nitride (hBN) and graphene nanoplatelets (GNP) were incorporated at concentrations of 0.5, 1, and 1.5 wt%. This study presents the first direct comparison of these nanoparticles incorporated into a eutectic fatty acid ester based PCM to evaluate their impact on structural and thermal characteristics. The results demonstrate that GNP achieved the superior enhancement. In the sample containing 1 wt% hBN, the enthalpy value decreased to 174 J/g, representing an approximate 4% reduction compared to the pure EPCM, while the thermal conductivity increased by approximately 292%. In the material containing 1 wt% GNP, the latent heat slightly decreased to 176.3 J/g, a reduction of only 2.8%, remaining within optimal limits, while the thermal conductivity increased significantly by 462.8%. These findings suggest that the nanoparticle enhanced EPCM, with 1 wt% GNP demonstrating optimal performance, represents a promising candidate for low to medium temperature solar TES applications.

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Stimuli-response polymeric nanoparticles have emerged as a nanocarrier in the drug delivery systems. In this study, for the first time, a novel stimuli-responsive nanocarrier was synthesized with the combination of N-vinylcaprolactam, allyl alcohol, and carbon disulfide on the tungsten disulfide nanosheets for palbociclib delivery by near-infrared laser irradiation. The successful synthesis of this system was confirmed by different techniques. Response surface methodology and central composite design were applied to optimize conditions. The data shown that the highest sorption efficiency of drug was reached using the nanoadsorbent at pH = 4, contact time of 50 min, initial drug concentration of 20 mg L^− 1, and temperature of 28 °C. The non-linear analysis indicated that drug sorption fitted well with the pseudo-second-order kinetic model and the Langmuir isotherm model. The in vitro drug release from the nanocarrier was noticeably dependent on pH and temperature. In vitro drug release experiments indicated that the obtained nanocarrier controlled the release of the drug at a temperature of 45 °C and pH = 5.6, achieving 88.48 ± 0.26% release over 6 h. Additionally, most of the drug was released from the nanocarrier within 15 min (> 98%) under near-infrared laser irradiation. Furthermore, the prepared drug delivery system demonstrated that the drug release followed a non-Fickian diffusion mechanism with n = 0.5.

A new α-Mn₂O₃/carbon (Mn₂O₃/C) nanocomposite was synthesised via ultrasonication-assisted co-precipitation, calcination, and freeze-drying. The method involved forming a stable Mn–citrate precursor, which, upon calcination, yielded crystalline α-Mn₂O₃ embedded in a carbonaceous matrix. Structural investigations using FT-IR, XRD, and FE-SEM validated the development of a porous nanosheet morphology, with well-dispersed Mn₂O₃ nanocrystals closely integrated within a carbon matrix. The hierarchical porosity and graphitic domains improved ionic accessibility and charge transfer at the oxide-carbon interface. Electrochemical investigations revealed significant pseudocapacitive characteristics accompanied by Mn redox shifts. The Mn₂O₃/C electrode achieved a specific capacitance of 1700 F g^− 1 at 0.5 A g^− 1 in a 6 M KOH electrolyte. It maintains 94% of its efficiency after 5000 cycles, indicating high recyclability. The synergistic integration of Mn₂O₃ and Carbon in Mn₂O₃/C, along with its structural integrity and effective ion/electron transport, renders the material promising for supercapacitors.

Graphical Abstract

Accurate quantification of fludarabine (FLD) is of paramount clinical importance due to its narrow therapeutic index, where insufficient dosing compromises anticancer efficacy while overdosing leads to severe immunosuppression and toxicity. Reliable monitoring is therefore essential for personalized therapy and improved patient outcomes. To address this challenge, we designed bimetallic copper–nickel co-doped nitrogen-rich carbon dots (CuNi@NCDs) as a multifunctional nanozyme for dual-mode FLD detection. The synergistic Cu/Ni co-doping endowed the NCDs with robust peroxidase-mimetic activity and enhanced photoluminescence by facilitating H₂O₂ activation into highly reactive hydroxyl radicals (HO^•) and accelerating charge transfer across the carbon framework. This dual functionality enabled simultaneous colorimetric and ratiometric fluorescence sensing, providing cross-validated outputs that improve analytical reliability. Mechanistically, FLD selectively inhibited the catalytic activity through strong chelation with Cu/Ni centers while modulating the inner filter effect (IFE) of the oxidation product 2, 3-diaminophenazine (DAP), thereby generating distinct and complementary signal responses. The proposed assay achieved ultralow detection limits (16.0 nM by absorbance and 2.6 nM by fluorescence) and excellent recoveries (96.7–105.0%) in pharmaceutical and biological matrices, outperforming many existing analytical platforms. These findings demonstrate the potential of CuNi@NCD-based nanozymes as robust and versatile tools for clinical monitoring, therapeutic drug management, and broader bioanalytical applications.

This work reveals the significant improvement of thermoplastic polyurethane (TPU) characteristics via the novel integration of trace quantities of holmium oxide (Ho₂O₃) nanoparticles. XRD verifies the successful incorporation of nanoscale Ho₂O₃ with an average crystallite size of approximately 20.5 nm, resulting in a controllable decrease in polymer crystallinity and demonstrating significant interfacial synergy between the filler and the matrix. FTIR spectra and FESEM, in conjunction with elemental EDX mapping, confirm the uniform dispersion of nanoparticles and strong interactions between the polymer and filler. Optical evaluations reveal a significant rise in UV reflectance with a red shift in the absorption edge that broadens the band gap to 3.08 eV-an unequivocal sign of improved UV-shielding efficacy and heightened transparency in the visible spectrum. Photoluminescence investigations reveal distinct, intense emission peaks resulting from Ho³⁺ 4f-4f transitions, validating the function of Ho₂O₃ as an effective luminescence activator through efficient energy transfer from TPU. Dielectric experiments indicate significant enhancements: dielectric constants increase at low frequencies due to Maxwell–Wagner–Sillars polarization effects, but dielectric losses stay stable, ensuring optimal energy storage capacity. Modulus and impedance investigations demonstrate expedited dipolar relaxation and markedly diminished charge transfer resistance, with Ho₂O₃ nanoparticles facilitating efficient charge mobility pathways. These findings establish TPU/Ho₂O₃ nanocomposites as sophisticated, multifunctional materials with potential applications in next-generation UV-protective coatings, flexible optoelectronic devices, cutting-edge photonics, and efficient energy storage systems.

The development of multifunctional nanomaterials with antioxidant, antibacterial, and anticancer properties is of growing interest in biomedical research. In this study, hybrid nanoflowers (hNFs) were successfully synthesized using ellagic acid as the organic component and copper (Cu²⁺), cobalt (Co²⁺), and zinc (Zn²⁺) ions as the inorganic components. The resulting nanostructures were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). Their bioactivities were comprehensively evaluated, including antioxidant capacity (via DPPH and ABTS assays), acetylcholinesterase (AChE) inhibitory activity, cytotoxic effects on A549 human lung carcinoma cells (MTT assay), antibacterial activity against Staphylococcus aureus, Enterococcus faecalis (E. faecalis), Pseudomonas aeruginosa, Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA), and multidrug-resistant Escherichia coli (MDR E. coli) using the broth microdilution method, and antibiofilm activity against MRSA and MDR E. coli via crystal violet staining. Among the hNFs, EA@Zn-hNFs displayed the strongest antioxidant activity (DPPH IC₅₀: 13.50 ± 0.70 µg/mL; ABTS IC₅₀: 0.64 ± 0.01 µg/mL) and AChE inhibition (IC₅₀: 31.00 µg/mL), while EA@Co-hNFs showed the highest antibacterial potency, with MIC values of 16.00 ± 0.58 µg/mL against E. faecalis and 128.00 ± 1.02 µg/mL and 128.00 ± 0.83 µg/mL against both MRSA and MDR E. coli. EA@Co-hNFs also exhibited significant antiproliferative effects. Overall, the synthesized hNFs demonstrated dose-dependent multifunctional bioactivities and hold strong potential for future biomedical applications.