Journal of Nanoparticle Research最新文献

In this study, Cu₂O, CdS, and Cu₂O decorated with CdS nanorods were successfully synthesized and applied for the adsorption of crystal violet (CV) dye. Cu₂O had a cauliflower-like shape, while CdS underwent a phase transition from cubic to the hexagonal structure, forming nanorods anchored to the Cu₂O surface. The Cu₂O/CdS composite achieved the highest removal efficiency with 65% CV removal. Kinetic analysis revealed that the adsorption of CV onto CdS and Cu₂O/CdS followed the pseudo-second order model, with a rate constant (k₂) of 0.0268 g mg⁻¹ min⁻¹, indicating that chemisorption is the dominant mechanism. Equilibrium data were evaluated using the Langmuir and Freundlich isotherms, with the Freundlich model providing a superior fit (R² = 0.9522) and Freundlich constants​ of 17.969 mg g⁻¹ and 19.5865 mg g⁻¹ for CdS and Cu₂O/CdS, respectively, suggesting heterogeneous multilayer adsorption as the governing mechanism. The enhanced performance of the Cu₂O/CdS composite is attributed to the hierarchical morphological structure of Cu₂O and the hexagonal structure of CdS. Overall, the results demonstrate that Cu₂O/CdS is a promising adsorbent for removing dye from aqueous systems, offering high adsorption capacity, favorable kinetics, and heterogeneous adsorption behavior. 

Graphical Abstract. Schematic Illustration Of Cv Adsorption Process Using Cu₂O/CdS

Schematic illustration of CV adsorption process using Cu₂O/CdS

The interaction between cationic gold nanorods (GNRs) and tau protein was investigated to assess their potential in modulating tau aggregation, a central process in neurodegenerative diseases. Monodisperse GNRs with rod-shaped morphology (55 ± 4 nm length, 20 ± 3 nm width, aspect ratio ~2.75) and a defined longitudinal LSPR peak at 654 nm (FWHM ~77 nm) were synthesized. Incubation with tau (0–40 µM) caused only a slight decrease in LSPR intensity without peak shifts, confirming nanorod stability. Thioflavin T assays demonstrated potent, concentration-dependent inhibition of heparin-induced tau fibrillation, with ~70%, ~85%, and ~95% reduction in final ThT fluorescence at 5, 10, and 20 nM GNRs, respectively. Crucially, structural analyses via FT-IR and CD showed no significant transition to β-sheet content, preserving tau’s intrinsically disordered conformation. Fluorescence quenching studies revealed strong static quenching (K_SV = 5.4 µM⁻¹), indicating close proximity of tyrosine residues to the GNR surface likely through π–π stacking and hydrophobic interactions. This in vitro study establishes GNRs as effective, structure-preserving nanoscaffolds that inhibit tau aggregation by sequestering monomers. The key innovations of this work are the demonstration of this dual functionality, potent inhibition coupled with conformational preservation, and the elucidation of the anisotropic geometry of GNRs as a critical design parameter for achieving this structure-preserving mechanism. While promising, the mechanistic insights are limited to in vitro conditions, and further in vivo validation will be required.

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Graphene oxide (GO) and its surface-functionalized derivatives provide a promising platform for tailoring dielectric relaxation and thermal transport through chemical modification. However, a unified understanding of how surface chemistry governs these properties remains limited. In this work, GO, acid-functionalized GO (A-GO), and amine-functionalized GO (N-GO) were synthesized to systematically elucidate the influence of surface functionalization on frequency and temperature-dependent dielectric properties and thermal behavior. Structural and spectroscopic analyses confirmed successful incorporation of –COOH and –NH₂ groups, accompanied by reduced interlayer spacing, modified defect density, and distinct variations in nanoscale sheet morphology and lateral size distribution upon functionalization. Dielectric spectroscopy performed over a frequency range of 10^–2–10⁵ Hz and a temperature range of 25–100 °C revealed thermally activated, non-Debye relaxation dominated by interfacial polarization, with N-GO exhibiting significantly enhanced capacitance (~ 10^–3 F), dielectric permittivity (~ 10⁹), and AC conductivity (~ 10^–1 S m⁻¹) at 100 °C compared with GO and A-GO. Dielectric modulus analysis and impedance spectroscopy were additionally employed to further assess relaxation behavior and charge transport characteristics of the functionalized GO systems. Thermal conduction measurements of corresponding nanofluids demonstrated pronounced enhancement in thermal conductivity and diffusivity with increasing temperature and nanoparticle concentration, reaching up to ~ 71% thermal conductivity enhancement for N-GO nanofluids relative to the base fluid. This work provides the first comprehensive and systematic experimental investigation integrating dielectric relaxation analysis and thermal transport evaluation in acid and amine functionalized GO, offering new insights into the role of surface chemistry in governing multifunctional material performance.

This study investigates graphene-based nanosensors for oxygen (O₂) detection by examining geometrical and electronic structures, adsorption mechanisms, density of states (DOS), charge transfer, sensor sensitivity, and recovery time. Using density functional theory (DFT), we analyze monolayer graphene (MG), AB-stacked bilayer graphene (BG), and twisted bilayer graphene (TwBG) with a 21.78° twist angle, both in pristine and beryllium-doped forms. The results show physisorption in pristine structures and chemisorption in Be-doped configurations, leading to enhanced adsorption energies and improved sensor responses. AB-stacked BG exhibits lower adsorption energy, charge transfer, sensor sensitivity, and shorter recovery time compared to monolayer graphene, while TwBG demonstrates increased adsorption, charge transfer, and sensitivity, highlighting a molecular-tuning effect due to interlayer interactions. Among monolayer systems, Be-doped MG shows the highest O₂ detection capability. In bilayer systems, TwBG outperforms AB-stacked graphene in both adsorption energy and sensor sensitivity, regardless of Be doping. These findings position TwBG, particularly when Be-doped, as a promising platform for advanced gas-sensing applications, offering enhanced efficiency, adaptability, and performance.

rGO/ V₂O₅ nanowire composites were synthesized via a green hydrothermal process, and the effect of hydrothermal duration on their morphology and photocatalytic performance was systematically evaluated. The composite prepared at 36 h exhibited the most uniform nanowire architecture and the strongest interfacial coupling. Under simulated solar irradiation, this sample achieved 95.5% degradation of methylene blue (20 mg/L) within 240 min, significantly outperforming pristine V₂O₅. Radical-trapping experiments confirmed that superoxide radicals (O₂^•−) and photogenerated holes (h⁺) are the primary active species, whereas hydroxyl radicals (•OH) contribute marginally. A mechanism is proposed in which photoexcited electrons transfer from V₂O₅ to rGO, where rGO acts as an electron sink that suppresses electron–hole recombination and promotes O₂ reduction to O₂^•−,thereby accelerating pollutant degradation into CO₂, H₂O, and inorganic ions. These results demonstrate the synergistic effect of rGO–V₂O₅ coupling and highlight a sustainable strategy for developing efficient photocatalysts for environmental remediation.

Mucosal vaccines offer a promising strategy for inducing site-specific immunity, but their effectiveness depends heavily on safe and efficient delivery systems. This study aims to study exosome-functionalized carbonate apatite (CHA-EXO) nanoparticles as a novel immunomodulatory adjuvant for oral mucosal vaccination. The CHA nanoparticles were synthesized and functionalized with mesenchymal stem cell-derived exosomes with physical adsorption. Their physicochemical properties, including functional groups, morphology, size distribution, and surface charge, were characterized. Loading efficiency and stability were observed with Bradford assays. Cytocompatibility was assessed in RAW264.7 and TR146 cells using the MTT assay. Comparative analysis was performed against aluminum hydroxide as a conventional adjuvant. The synthesized CHA-EXO nanoparticles exhibited a nanoscale diameter of approximately 100–120 nm, with a moderate increase in size following exosome functionalization in a concentration-dependent manner. They maintained a stable dispersion, showing surface charges of −31.63 to −37.48 mV in water and around −26 mV in artificial saliva. The nanoparticles demonstrated high cytocompatibility in both TR146 and RAW264.7 cells (> 75% viability), performing better than aluminum hydroxide at comparable moderate doses. Furthermore, the functionalized nanoparticles formed stable complexes with high loading efficiency, reaching 93.89% at elevated exosome concentrations, and released only 19.40% of the cargo within 24 h. These findings indicate exosome immobilization and enhanced potential for increased cellular interaction. The CHA-EXO nanoparticles show promise as a stable and biocompatible oral mucosal adjuvant, offering both physicochemical stability and favorable cell interactions.

Radiotherapy is a cornerstone of cancer treatment but is limited by its lack of specificity, causing damage to both healthy and malignant tissues. pH-sensitive nanoparticles have emerged as innovative radiosensitizers, exploiting the acidic tumor microenvironment to enhance targeted drug release, increase radiation-induced reactive oxygen species (ROS), disrupt DNA repair, and modulate key cellular pathways such as STING activation, JNK inhibition, and G2/M cell cycle arrest. This review highlights recent advances in metallic, polymeric, nanogel, and hybrid pH-sensitive nanoparticles, integrating molecular mechanisms with imaging-guided strategies to improve tumor selectivity, radiosensitization efficiency, and therapeutic outcomes. While these nanoparticles show significant preclinical promise, challenges including heterogeneous tumor microenvironments, limited tissue penetration, immune modulation, systemic toxicity, and hurdles in clinical translation remain. Collectively, pH-sensitive nanoparticles represent a promising strategy for enhancing radiotherapy efficacy, and overcoming current translational barriers is critical to realizing their full therapeutic potential.

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Degradation of pesticides (e.g., chlorpyrifos (CP)) and their metabolites is an area of evolving research. Palladium nanoparticles (Pd NPs) synthesis was achieved by microbial consortia from sludge to be used later as catalysts for the degradation of 3,5,6-trichloro-2-pyridinol (TCP), CP’s metabolite. Hydrogen (H₂) and glucose were used as electron donors to reduce Pd(II) and synthesize Pd NPs. When both glucose and Pd NPs were present, TCP removal exceeded 90% but suggested the presence of potential intermediates, consistent with a stepwise dechlorination. In contrast, H₂ microcosms with Pd NPs achieved > 95% TCP removal, but when lacking Pd NPs, microcosms supplemented only with H₂ showed marginal TCP degradation. Azospira and Thauera were dominant across all microcosms and could be dechlorinating TCP and producing Pd NPs. Clostridium dominated the microcosm with glucose and Pd, which pointed to its role in fermenting and generating H₂ to be later used for Pd NP production. Abiotic control microcosms showed Pd NPs synthesis with H₂ as an electron donor but not with glucose; therefore, microorganisms were needed for Pd NPs synthesis if glucose is provided. While several studies have focused on synthetic microbial consortia or single strain research for TCP microbial degradation, this research demonstrated the capacity of naturally occurring microbial consortia to degrade TCP with the aid of Pd NPs, which were also synthesized biologically.

The accurate and rapid detection of Mycobacterium tuberculosis (M. tuberculosis) is essential for the effective treatment of tuberculosis. In this work, perovskite/silica nanocomposites CsPbBr₃@MSNs-PbBrOH (DP-CPB) were synthesized via a dual in situ-coating strategy, encapsulating CsPbBr₃ nanocrystals with mesoporous silica and PbBrOH. The resulting nanocomposites exhibited excellent stability in physiological media. The nanocomposites’ surface was conjugated with the MS10-Trunc aptamer specific for Mtb malate synthase (MtbMS). Leveraging the aptamer’s high affinity, we developed two fluorescent aptasensors: one based on a 96-well plate for MtbMS detection, and another employing magnetic nanoparticles for the detection of Mtb bacterial strains (Mtb H37Rv). The sensors demonstrate dynamic ranges of 50-750 nM for MtbMS and 10²-10⁷ CFU/mL for Mtb H37Rv, with low limits of detection (LOD) of 1.17 nM and 3 CFU/mL, respectively. The aptasensors possess the comprehensive advantages of the highly efficient photoluminescence of DP-CPB, high specificity, and fast detection of MtbMS and H37Rv. The aptasensor was successfully applied for the determination of Mtb H37Rv, revealing the vast potential of perovskites in biosensing.

Textile dye effluents are persistent contaminants that require robust, low-cost photocatalysts that are operable under broad-spectrum illumination. Herein, we report the solvent-free ex situ synthesis of ternary ZnO-TiO₂-g-C₃N₄ (85:5:10, w/w) nanohybrids and benchmark them against their single and binary counterparts for rhodamine 6G (R6G) degradation. Comprehensive physicochemical analyses (XRD/Rietveld, FTIR, UV–Vis DRS, FE-SEM, HR-TEM, SAED, PL, BET, Raman, and XPS) jointly confirm crystalline phase coexistence with intimate interfacial coupling (Zn-O-Ti linkages), bandgap narrowing to 2.85 eV, and interfacial charge redistribution with oxygen vacancy signatures beneficial to reactive oxygen species (ROS) generation. Compared with pristine and binary materials, the ternary nanohybrids exhibited markedly quenched PL emission, reduced charge transfer resistance, and enhanced defect density, correlating with 99.99% R6G removal in 180 min with a first-order R6G degradation rate constant of 2.16 × 10⁻² min⁻¹. Antioxidant performance (DPPH assay) was also enhanced to compare with bare, reaching 71.78% radical scavenging at 100 µg/mL. The catalyst retained > 96% removal efficiency over five reuse cycles without discernible structural degradation (post-cycle XRD and FTIR), underscoring operational stability. Collectively, these results demonstrate that the solvent-free fabrication of ternary ZnO-TiO₂-g-C₃N₄ nanohybrids, dual (photocatalytic/antioxidant) functionality, and recyclability make this system a promising platform for water remediation and related bio-interfaces, subject to future cytocompatibility validation.

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