Nanoscale Research Letters最新文献

Safe and effective antimicrobial treatment strategies are urgently required for the prevention and control of infectious diseases. While silver-based nanoparticles (AgNPs) are currently acknowledged as the most potent metal-based antibacterial agents, their potential cytotoxicity poses a significant barrier to further clinical applications. Herein, we synthesized carbonaceous coated silver nanocore (Ag@C) core-shell nanoparticles and investigated their material properties, biocompatibility, and antibacterial efficacy. The produced Ag@C exhibited a uniform core-shell structure with an overall diameter of 256.40 nm, a shell thickness of 92.20 nm, and a silver core diameter of 67.45 nm. Under irradiation with 808 nm near-infrared (NIR) irradiation, Ag@C demonstrated excellent photothermal conversion efficiency. The results from apoptosis detection via flow cytometry, CCK-8 cytotoxicity assays, and live/dead cell staining using Calcein-AM/PI, collectively indicated that Ag@C displayed no significant cytotoxicity. Hemolysis tests further confirmed the good biocompatibility of Ag@C. Quantitative analysis through plate counting assays revealed that Methicillin-resistant Staphylococcus aureus (MRSA) co-cultured with Ag@C were significantly eradicated by NIR irradiation; this finding was corroborated by bacterial live/dead staining observed under confocal laser scanning microscope (CLSM). Our results indicate that Ag@C combined with photothermal therapy (PTT) exhibits substantial antibacterial effects in vitro while maintaining high biosafety standards, suggesting promising prospects for clinical application.

This study investigated the three-dimensional magnetohydrodynamic flow and heat transfer of the ternary nanofluid (Cu–Al₂O₃–TiO₂/water) between two coaxial rotating and stretching disks embedded in a porous medium. The model incorporated magnetic field, viscous dissipation, Forchheimer drag, thermal relaxation, disk stretching, and slip boundary conditions to capture realistic flow and thermal behavior. The governing equations are transformed into nonlinear ordinary differential equations via similarity transformations. The semi-analytical solution is obtained using the Homotopy Analysis Method (HAM). COMSOL Multiphysics (FEM) is employed to simulate the full 3D field by validating the analytical result. A parametric study revealed that the ternary nanofluid exhibited superior momentum and heat transfer compared to hybrid and simple nanofluids. Magnetic field and porous drag suppressed velocities but enhanced thermal accumulation, whereas disk rotation and stretching amplified both velocity and Nusselt number. Slip parameters reduce skin friction and heat transfer, while the Eckert number increases flow resistance and temperature. Excellent agreement between HAM and COMSOL confirmed the reliability of the solutions. The findings provide valuable guidelines for enhanced thermal management in industrial and electronic systems, and the study presented a novel analysis of ternary nanofluid behavior in complex rotating and stretching disk geometries.

This study explores the green synthesis of gold nanoparticles (AuNPs) using the aqueous extract of Boerhavia diffusa L., a plant known for its medicinal properties. The synthesis of AuNPs was confirmed through UV–Vis spectroscopy, showing a characteristic surface plasmon resonance peak at 551 nm, indicating successful nanoparticle (NPs) formation. The physicochemical properties of the NPs were further analyzed using FTIR, XRD, SEM, and DLS, revealing a crystalline structure, spherical morphology, and an average size of 53.17 ± 0.58 nm. The biogenic AuNPs were evaluated for their antimicrobial, antifungal, antioxidant, and anticancer activities. AuNPs exhibited significant antibacterial effects against Listeria monocytogenes, Bordetella bronchiseptica, and Escherichia coli, with zone of inhibition ranging from 25 to 27 mm. In antifungal assays, AuNPs displayed potent activity against Candida albicans, Aspergillus niger, Cryptococcus neoformans, and Trichophyton rubrum, with inhibition zones between 78 and 86 mm. The antioxidant potential was also demonstrated through DPPH, FRAP, and TPC assays, with AuNPs showing ~ 80% radical scavenging activity. Furthermore, cytotoxicity analysis revealed that AuNPs reduced the viability of HepG2 cancer cells by approximately 39% at 100 µg/mL. These findings highlight the potential of BD@AuNPs as multifunctional nanomaterials for biomedical applications, offering eco-friendly and sustainable alternatives for drug delivery and therapy.

In this work, a solvent evaporation casting approach was used to prepare ZnO@PDA/Zein nanocomposite films, where polydopamine-modified zinc oxide nanoparticles (ZnO@PDA NPs) were incorporated into a zein matrix as the film-forming agent. This nanocomposite film adhered uniformly to the surface of oral therapeutic instruments and exhibited good antibacterial effects. At a doping concentration of 1.2 mg/mL, the film exhibited an antibacterial effect against Gram-negative bacteria such as Escherichia coli (E. coli), and at a doping concentration of 0.6 mg/mL, the film exhibited antibacterial effects against Gram-positive bacteria such as Staphylococcus aureus (S. aureus) and Streptococcus mutans (S. mutans), along with good biocompatibility. This study introduces a novel ZnO@PDA/Zein nanocomposite film with enhanced antibacterial efficacy and biocompatibility, offering a promising solution for preventing biofilm formation on oral therapeutic instruments.

TiO₂ nanoparticles were synthesized using Cocos nucifera pollen extract through an eco-friendly green approach and evaluated for their multifunctional properties. XRD confirmed a crystallite size of 17.4 nm, while HRTEM showed particle sizes ranging from 5 to 100 nm. The biogenic TiO₂ NPs exhibited strong photocatalytic degradation of methylene blue, achieving 97.8% efficiency under sunlight and 98.5% under UV within 180 min. They also demonstrated significant antibacterial activity against Staphylococcus aureus (23.0 mm) and Escherichia coli (29.5 mm), along with biofilm inhibition rates of 86.57% and 70.34%, respectively. The study highlights the novelty of using Cocos nucifera pollen as a biogenic reducing agent and demonstrates the potential of the synthesized nanoparticles for wastewater treatment and antimicrobial applications.

Graphical abstract

Background

Current medical problems are complex and require a new approach. Nanomaterials can address these complications. Silver nanoparticles (AgNPs), in particular green-synthetized particles, because of their unique properties have attract the attention of scientist. The objective of this work deals with using Elaeagnus angustifolia (EA) leaf extract as a reducing agent for biofabrication of AgNPs and investigation of its antibacterial and anti-cancer properties.

Method

UV–Visible spectroscopy (UV–Vis), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), transmission Electron Microscopy (TEM), Scanning-Transmission Electron Microscope (STEM) and atomic force microscopy (AFM) techniques were used for characterization of the biosynthesized AgNPs. Antimicrobial efficacy was measured through disk diffusion and minimum inhibitory concentration (MIC) methods, while cytotoxic effects on PC-3 cancer cells were evaluated using the MTT assay.

Result

The biosynthesized AgNPs exhibited a strong surface plasmon resonance peak at approximately 441 nm, confirming successful synthesis. XRD analysis indicated a face-centered cubic structure, with crystallite sizes 27.04 nm. Antibacterial tests revealed significant activity against E. coli and K. pneumoniae, with AgNPs demonstrating comparable efficacy to standard antibiotics. In particular, AgNPs demonstrated successful activity on E. coli with an MIC value of 113.24 ± 14.36 and an inhibition zone of 24.32 ± 1.25 mm, comparable to standard antibiotics Furthermore, the AgNPs displayed notable cytotoxic effects on PC-3 cells, with an IC₅₀ value of 58.77 µg/mL.

Conclusion

The results explore the potential of leaf extract of Elaeagnus angustifolia as an effective agent for the green synthesis of AgNPs that have significant antibacterial properties. This study supports the application of green synthesis in medical therapies.

Triple-negative breast cancer (TNBC) represents the most aggressive breast cancer subtype and is characterized by the absence of estrogen receptor, progesterone receptor, and HER2 expression; this subtype affects approximately 12–20% of all breast cancer cases, with a disproportionately poor prognosis and limited therapeutic options. The lack of targetable receptors excludes TNBC patients from hormone therapy and HER2-targeted treatments, resulting in the use of chemotherapy as the primary intervention, which is often associated with severe systemic toxicity and drug resistance. Albumin-based nanoplatforms have emerged as promising solutions to address these therapeutic challenges by exploiting the inherent biocompatibility, biodegradability, extended circulation half-life, and natural tumor-targeting properties of albumin through interactions with gp60 and SPARC receptors that are overexpressed in TNBC tissues. This comprehensive review examines the molecular design principles, fabrication strategies, and targeting mechanisms of albumin nanocarriers, including passive targeting via the enhanced permeability and retention (EPR) effect and active targeting through receptor‒ligand interactions with uPAR, EGFR, CD44, CXCR4, and folate receptors. We analyze diverse therapeutic payloads, including conventional chemotherapeutics (paclitaxel, doxorubicin, and docetaxel), natural products (curcumin and resveratrol), and molecular therapeutics (siRNAs and CRISPR/Cas9) delivered via albumin nanoplatforms. The clinical evidence supporting nab-paclitaxel in combination with immune checkpoint inhibitors has demonstrated significant improvements in progression-free survival and objective response rates in PD-L1-positive mTNBC patients, whereas real-world studies have confirmed manageable safety profiles. However, several challenges remain, including drug loading limitations, nanocarrier stability under physiological conditions, interpatient variability in EPR effectiveness, potential immunogenicity of modified albumin, and the inherent molecular heterogeneity of TNBC subtypes, which may require personalized approaches. Future directions emphasize the development of multistimuli-responsive albumin nanocarriers, integration with gene editing and immunotherapy, artificial intelligence-guided design optimization, and precision medicine strategies tailored to individual tumor profiles. The convergence of the natural tumor affinity of albumin with advanced nanotechnology holds substantial promise for overcoming drug resistance, enhancing therapeutic specificity, and improving clinical outcomes in TNBC patients, positioning albumin-based nanomedicine as a transformative approach in precision oncology.

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Plasmonic biosensors, particularly Surface Plasmon Resonance and Surface-Enhanced Raman Spectroscopy, have gained significant attention for real-time, label-free biochemical detection. However, optimizing these sensors for maximum sensitivity and selectivity remains a challenge due to their complex plasmonic interactions with different biomolecules. This work proposes SERA, an AI driven framework that integrates machine learning algorithms with experimental Surface-Enhanced Raman Spectroscopy (SERS) data for the predictive modeling and optimization of plasmonic sensing performance. Using supervised learning techniques, the ML models are trained on a spectral dataset - SERS-DB obtained from various plasmonic nanostructures. The model predicts key parameters such as resonance shift, intensity variations, and molecular binding efficiency, allowing for rapid optimization of biosensor designs without extensive trial-and-error experimentation. This approach accelerates plasmonic biosensor development and enables real-time adaptive sensing based on live data. The results through evaluation on the SERS-DB database with 420 samples for training and 180 for the testing phase, 6 classes like Thiacloprid, Imidacloprid, Thiamethoxam, Nitenpyram, Tetrahydrofolate, and Dihydrofolate, an accuracy of 92%, precision & recall of 90%, and F1-score of 92% were attained. The SERA model excelled with an overall score of around 0.90 in all 6 classes, proving additional superiority in biosensing applications. Further comparative analysis of the proposed approach with conventional methods underscores the best performance in accuracy with 92%, sensitivity, 1000 nm/RIU, and 95% in optimization efficiency. Overall, this research highlights a scalable and cost-effective strategy for advancing biosensor technology in medical diagnostics, environmental monitoring, and bio photonics.

In this study, graphene oxide (GO) derived from rice husk was functionalized with silver nitrate (AgNO₃) through a chemical co-precipitation method, and its biomedical applications were systematically investigated. Drug release experiments revealed a pH-responsive profile, where at pH 4.0 the cumulative release reached 32.6 ± 1.6% after 24 h, compared to 12.4 ± 1.8% at pH 7.4, highlighting its potential for targeted delivery to cancer cells. Reactive oxygen species (ROS) analysis and flow cytometry demonstrated that RH-GO/AgNO₃ treatment elevated oxidative stress and triggered apoptosis in HeLa cells. Furthermore, 5-fluorouracil (FU) was successfully loaded onto the nanocomposite surface via non-covalent interactions. Cytotoxicity assessment by MTT assay showed that FU-loaded RH-GO/AgNO₃ had the strongest anticancer activity, with an IC₅₀ value of 256.3 µg/mL. ROS levels in treated HeLacells increased significantly (40.17%) compared to the control group (19.45%), and flow cytometry confirmed a reduction in cell viability (69.5%) accompanied by enhanced apoptosis (early: 8.3%, late: 4.0%) and necrosis (18.2%). Collectively, these findings indicate that RH-GO/AgNO₃-FU induces cancer cell death predominantly via apoptosis. Overall, this work demonstrates that agricultural waste-derived nanomaterials can serve as cost-effective and sustainable platforms for advanced drug delivery in cancer therapeutics.

Graphical abstract