Search Results (1,001)

This study investigated whether salinity during cultivation of the aquatic plant Lemna minor (duckweed) influences the phytochemical composition of plant extracts and the properties of green-synthesized zinc oxide nanoparticles (ZnO NPs). Duckweed was cultivated under 0, 10, and 100 mM NaCl, followed by Orbitrap metabolomic profiling, nanoparticle synthesis, physicochemical characterization, and evaluation of antioxidant and antimicrobial activities. Orbitrap analysis revealed pronounced salinity-dependent changes in extract composition, including increased abundance of several flavonoids, glycosylated flavones, and hydroxycinnamic acid derivatives in the order 0 < 10 < 100 mM. ZnO nanoparticle formation was supported by UV–Vis spectroscopy, which showed characteristic absorption features around 360 nm, and by powder X-ray diffraction (PXRD), which indicated the predominance of the hexagonal wurtzite ZnO phase in all samples. SEM–EDS analysis revealed Zn- and O-rich materials consisting of micron-scale aggregates and finer submicron structures. Raman spectra were dominated by fluorescence, which increased with salinity treatment and may reflect differences in surface-associated phytochemicals rather than substantial changes in the ZnO crystal structure. Nanoparticles synthesized using extracts from salt-stressed duckweed exhibited higher total phenolic content (up to 66.79 ± 0.15 µM GAE g⁻¹), antioxidant activity (up to 55.01 ± 0.21%), and antimicrobial activity against Staphylococcus haemolyticus D4-2-100/1 (inhibition zone up to 1.55 ± 0.05 cm). Although the mechanisms underlying these differences remain to be fully elucidated, the results suggest that salinity-induced changes in duckweed metabolism may influence the biological properties of the resulting nanomaterials. Overall, this study highlights the potential of manipulating cultivation conditions to modulate plant extract composition and, consequently, influence the characteristics and functionality of green-synthesized ZnO nanoparticles. Full article

Introduction: Heavy metal contamination in water represents a major environmental and public health challenge because toxic ions frequently occur as complex multi-species mixtures rather than isolated pollutants. This study presents a numerical design and optimization of a surface plasmon resonance (SPR) sensor based on a LaF/Au/BaTiO₃/WS₂ heterostructure for monitoring refractive-index changes associated with mixed heavy metal ions in aqueous media. Methodology: The optical response of the multilayer sensor was evaluated using the transfer matrix method under TM-polarized illumination at 633 nm. Systematic optimization was performed for the prism substrate, Au thickness, dielectric oxide layer, and 2D nanomaterial interface. The final configuration consisted of a LaF prism, 50 nm Au film, 2.0 nm BaTiO₃ spacer, and 0.80 nm WS₂ monolayer. Sensor performance was assessed using resonance-angle shift, sensitivity, detection accuracy, quality factor, figure of merit, FWHM, attenuation, and estimated limit of detection. Results and Discussion: The optimized LaF/Au/BaTiO₃/WS₂ configuration produced stable simulated SPR responses across single, binary, quaternary, and five-ion heavy metal matrices. The WS₂ monolayer provided the highest angular displacement among the evaluated 2D materials, while BaTiO₃ improved field confinement and limited optical damping in the numerical model. The configuration maintained attenuation near 1.6%, FWHM values around 7.9°, detection accuracy between 0.030 and 0.032 deg⁻¹, and model-based refractometric LoD values down to 3.49 × 10⁻⁵ RIU under the assumed angular-resolution criterion. Conclusions: The proposed LaF/Au/BaTiO₃/WS₂ SPR configuration provides a numerical framework for label-free monitoring of refractive-index changes associated with complex heavy-metal-ion mixtures in contaminated water. Experimental fabrication and testing are required to validate the simulated performance. Full article

Low-dimensional (0D/1D/2D) nanomaterials exhibit unique physical and chemical properties different from general bulk materials due to enhanced surface and interface contributions and quantum confinement effects, which strongly modulate electronic structures. Boron, with atomic number 5, can form multicenter bonds and enables the construction of structurally diverse nanomaterials across different dimensionalities. In this review, boron-based low-dimensional materials are systematically organized from 0D clusters to 1D nanostructures and 2D sheets, and their optical and electrical properties are discussed in relation to structural factors such as dimensionality. This review provides an integrated perspective on how dimensional expansion and structural design govern the optical and electrical properties of boron-based nanomaterials. Full article

Effective wound management remains a critical challenge in modern medicine, requiring a delicate balance among infection control, hemostasis, and tissue regeneration. Biopolymer-based hydrogels have emerged as leading candidates for medical use due to their biocompatibility, moisture-retention capabilities, and structural similarity to the natural ECM. This review provides a comprehensive overview of the transition from passive dressings to intelligent, multifunctional hydrogel scaffolds. We first examine the biological mechanisms of wound healing and the fundamental roles of hydrogels in maintaining an optimal microenvironment. Central to this discussion is the integration of conductive materials (including conductive polymers, carbon-based nanomaterials, and metal nanoparticles), which empower hydrogels with bio-sensing and electromechanical stimulation capabilities. Furthermore, we explore how 3D printing technologies enable the fabrication of personalized, high-precision scaffolds. The review also discusses the emerging role of integrated monitoring systems and machine learning algorithms in enhancing diagnostic accuracy. By synthesizing current research, this review identifies critical engineering hurdles and outlines the future trajectory toward automated, closed-loop wound-care systems in clinical practice. Ultimately, while these advanced electronic scaffolds offer revolutionary therapeutic paradigms, this review underscores that balancing electroconductivity with chronic cytocompatibility, refining multi-modal biosensor calibration, and navigating complex regulatory evaluation pathways remain critical prerequisites. Overcoming these fundamental translational bottlenecks is essential to realizing the next generation of automated clinical wound care. Full article

The field of infrared (IR) photodetection is undergoing rapid development through the emergence of solution-processable nanoparticle (NP)-based materials and fabrication strategies. This review critically examines recent advances in fabrication approaches for NP-based IR detectors, emphasizing the relationship between synthesis, surface engineering, deposition processes, and device architecture in determining detector performance. Representative material platforms are discussed, including colloidal quantum dots (CQDs) such as PbS and HgTe, which enable tunable operation from the near-infrared (NIR) and short-wave infrared (SWIR) to selected mid-wave (MWIR), long-wave (LWIR), and emerging very-long-wave infrared (VLWIR) regimes depending on material composition and operating conditions. Further platforms including plasmonic metal NPs, black phosphorus, and topological nanomaterials are evaluated for their unique mechanisms of optical enhancement and broadband response. Fabrication approaches including continuous-flow synthesis, ligand exchange, blade coating, inkjet printing, electrophoretic deposition, and other scalable solution-processing methods are analyzed with respect to their influence on film quality, charge transport, interface engineering, and integration compatibility. The review further compares major device architectures, including photoconductors, photodiodes, plasmonic absorbers, and phototransistors, using key performance metrics such as specific detectivity (D*), responsivity (R), response speed, and operating temperature, while emphasizing the importance of measurement conditions in cross-platform comparisons. Critical challenges including dark-current generation, 1/f noise, transport limitations associated with ligand chemistry, environmental instability of narrow-bandgap materials, manufacturability constraints, and toxicity considerations are also discussed. Emerging directions such as neuromorphic sensing, CMOS-compatible integration, and sustainable lead-free nanomaterials are highlighted. By linking nanoscale material design and fabrication processes to device-level performance, this review provides a framework for advancing NP-based IR technologies toward scalable and application-relevant sensing systems. Full article

The use of hydrolytic enzymes is one of the most promising methods for combating bacterial biofilms. However, the use of native enzymes is limited by the rapid loss of activity under unfavorable conditions. Immobilization of enzymes on carbon nanoparticles enhances their stability, allows for biocatalyst reuse, and creates a synergistic effect due to the intrinsic antimicrobial properties of the nanomaterials. The aim of this investigation was to create and comparatively analyze conjugates of acid and alkaline proteases with carboxylated multiwalled carbon nanotubes (MWCNTs-COOH) and to assess their effect on the formation and destruction of E. coli VKM B-3858D biofilms. The immobilization efficiency and kinetics of enzyme adsorption on the support were quantified by determining the protein concentration using the Bradford assay. The morphology and dispersion of the resulting conjugates were analyzed using atomic force microscopy (AFM). Protease activity was determined by a modified Anson method using the Folin–Ciocalteu reagent. Biofilm biomass was determined using crystal violet staining. The binding efficiency of the acid protease to MWCNTs-COOH was shown to reach 93%, which is significantly higher than that of the alkaline protease. The highest degree of immobilization was observed at a protein concentration of 117–338 μg/mL (10–20 mg/mL of the enzyme preparations). The interaction of the acid protease with the carbon nanoparticles increased dispersion, reducing the size of aggregates from ~1 μm to ~68 nm. As a result, acid protease conjugates with MWCNTs-COOH significantly reduced the biofilm biomass compared to both the enzyme-free control and the native enzyme. Alkaline protease, unlike the acid protease, destroys mature biofilms, and immobilization on MWCNTs-COOH enhances this ability. Native alkaline protease and acid protease conjugates with MWCNTs-COOH are effective in combating the biofilm formation of Gram-negative bacteria, while alkaline protease conjugates are suitable for disrupting mature biofilms. Full article

Silver (Ag) and gold (Au) nanoparticles (NPs) are widely used in biomedicine, electronics, and catalysis, but their potential toxicity raises occupational health concerns. This study assessed the cytotoxicity and cellular interactions of Ag and Au NPs in human bronchial epithelial cells (BEAS-2B) using a standardized OECD three-tiered approach, alongside characterization of lung-deposited surface area (LDSA) concentrations during NP synthesis, which remained within ranges typically reported in occupational environments. Transmission electron microscopy revealed that AgNPs formed irregular clusters (~8.7 nm primary size, >30 nm aggregates), whereas AuNPs remained spherical (~13.4 nm). Real-time cytotoxicity analysis (xCELLigence) showed acute toxicity of AgNPs at 5 μg/cm², while AuNPs exhibited no cytotoxic effects. Dark-field and 3D hyperspectral imaging demonstrated that some AgNPs were internalized by BEAS-2B cells, whereas AuNPs remained mostly on the cell surface, indicating that uptake alone does not determine cytotoxicity. The greater dissolution potential of AgNPs and possible release of Ag⁺ ions may contribute to the enhanced cytotoxic effects observed in comparison to AuNPs, as suggested in previous studies. Although oxidative stress, mitochondrial dysfunction, and related cellular mechanisms were not directly assessed in the present study, the findings demonstrate differential cellular responses following nanoparticle exposure under realistic occupational exposure conditions. These results contribute to understanding nanoparticle–cell interactions and support the need for further mechanistic investigations to inform safer nanomaterial use. Full article

Antimicrobial resistance (AMR) is a growing global health concern driven by bacterial biofilm formation, which increases tolerance to treatments. Developing surface-based strategies to limit biofilm formation is therefore critical. Layered Double Hydroxides (LDHs) are 2D brucite-like nanomaterials with tuneable physicochemical properties that may reduce bacterial colonisation. Their ease of synthesis, with scalability potential for industrial production, alongside their characteristic and tunable physicochemical properties, makes them a promising nanostructured coating for antimicrobial applications. This study evaluates LDH thin-film coatings as intrinsic antimicrobial surfaces, focusing on the combined effects of chemical composition, nanotopography, and wettability on biofilm formation in Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. Four aluminium-based LDHs (ZnAl-NO₃, ZnAl-Cl₂, MgAl-NO₃, MgAl-Cl₂) were synthesised via coprecipitation or in situ growth on aluminium substrates. Materials were characterised by XRD, SEM, EDS, and contact angle measurements. Antimicrobial performance was assessed by quantifying colony-forming units (CFU mL⁻¹) after bacterial exposure. ZnAl-LDH surfaces showed significant antimicrobial activity against E. coli and S. aureus, while MgAl-LDHs showed no effect and occasionally increased bacterial growth. None of the LDH surfaces tested exhibited significant antimicrobial activity against P. aeruginosa strain. The antimicrobial performance of ZnAl-LDH can be attributed to the concurrent effect of the surface chemistry, wettability, and sharp platelet-like nanotopography. The results obtained demonstrate that ZnAl-LDH-based coatings are promising antimicrobial materials with potential relevance for translational research in clinical antimicrobial surface development. Full article

The rising incidence of viral infections demands the creation of innovative, biocompatible antiviral drugs with broad-spectrum effectiveness. This study combines the green synthesis, optimization, and characterization of silver nanoparticles (AgNPs) utilizing Dacryodes edulis (D. edulis) extract, assessing their antiviral, and antimicrobial characteristics. AgNPs were synthesized through the bio-reduction of silver nitrate with D. edulis water extract as a reducing, capping and stabilizing agent. The synthesis was refined through a Design of Experiments methodology. The characterization techniques, UV-Vis, Fourier-transform infrared, transmission electron microscopy, and dynamic light scattering, validated the successful synthesis of AgNPs with an average size of 101.56 ± 28.22 nm (TEM) and 156 ± 0.81 nm (DLS), a polydispersity index of 0.34, and a zeta potential of −22 mV. High-resolution liquid chromatography–tandem mass spectrometry analysis identified some bioactive compounds which enhance the antimicrobial and antiviral properties of the samples. Enzyme kinetics experiments revealed substantial inhibitory efficacy against the SARS-CoV-2 papain-like protease (PL-pro), with AgNPs exhibiting a lower IC₅₀ (0.271 ± 0.051 mg/mL) than the D. edulis extract (0.337 ± 0.043 mg/mL). The AgNPs exhibited MIC of 0.063 mg/mL for E. coli, 0.125 mg/mL for S. aureus and 0.08 mg/mL for S. pyrogens. The corresponding MBC values were 0.125 mg/mL, 0.25 mg/mL and 0.31 mg/mL, respectively. The fungal strains C. glabrata and C. albicans displayed MIC of 0.63 mg/mL and 0.31 mg/mL, respectively, and MBC values of 0.63 mg/mL and 0.31 mg/mL, respectively. This study underscores the potential of D. edulis-derived AgNPs as a cost-efficient, environmentally sustainable, and highly bioactive antibacterial and antiviral nanomaterial, facilitating the advancement of nanotechnology-based therapies for viral infections. Full article

We study the planar dynamics of a charged particle subjected to a radially repulsive inverted harmonic potential and a perpendicular uniform magnetic field, a configuration that is relevant to nanoscale-charged transport and confinement in low-dimensional systems. The competition between the destabilizing central repulsion and magnetic field-induced rotational motion gives rise to rich trajectory behavior, including spiraling, unbounded escape, and parameter-dependent quasi-confined motion. The governing coupled differential equations of motion are solved analytically. The resulting trajectories are classified as functions of system parameters. The proposed framework provides insight into charge carrier dynamics in nanostructured environments such as quantum wells, 2D materials, and plasma-like nanosystems, where effective repulsive potentials may arise from external gating or collective interactions. In addition, the model offers a classical analogue for interpreting features associated with magnetic confinement in non-equilibrium or unstable regimes. These results contribute to the theoretical foundation for designing and controlling charged particle motion in emerging nanomaterials and devices. Full article

Latent fingerprint development on rough non-porous substrates using fingerprint powders remains challenging because surface microstructures reduce particle-adhesion selectivity and weaken the contrast between ridges and the background. In this study, Cs₂NaBi_0.6Er_0.4Cl₆ double-perovskite nanoparticles were prepared by a solvothermal method and investigated as fingerprint-development particles for latent fingerprints on frosted plastic substrates. Structural characterization by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) indicated that Er³⁺ was incorporated into the host matrix and that the product consisted of spherical nanoparticles with smooth surfaces, relatively uniform particle-size distribution, and good dispersibility. Comparative experiments involving 40 categories of latent fingerprint samples showed that the Cs₂NaBi_0.6Er_0.4Cl₆ nanoparticles outperformed conventional powders in developing fingerprints on frosted plastic substrates. Quantitative grayscale analysis using Image J 1.53K and Origin 2024 further showed that the development contrast, expressed as the D value, reached 51.21 for sebum-rich fingerprints and 35.87 for oil-contaminated model fingerprints, both of which were higher than those obtained with the other three powders. Because the fluorescence of Cs₂NaBi_0.6Er_0.4Cl₆ under UV excitation was weaker than that of the commercial red fluorescent powder, we attribute the improved development performance mainly to selective adhesion of the particles to fingerprint residues rather than to fluorescence intensity alone. In addition, the material maintained good performance for aged fingerprints within 10 days and for developed fingerprints stored for up to 8 days. These results suggest that selective residue-affinitive adhesion, possibly assisted by the hydrophilic or moisture-affinitive nature of the ionic double-perovskite particles, plays an important role in improving fingerprint development on rough non-porous substrates. This study provides a physical perspective for latent fingerprint development on rough non-porous substrates and broadens the forensic-science application of lead-free double-perovskite nanomaterials. Full article

Dendroctonus valens LeConte represents a major invasive pest species in China. Both larvae and adults primarily feed on the phloem of the tree trunk base and roots, disrupting nutrient transport and leading to host tree mortality, which poses a severe threat to forest ecosystems and the forestry economy. Juvenile hormone acid methyltransferase (JHAMT) is a key enzyme in insect juvenile hormone (JH) biosynthesis. In this study, we identified a JHAMT-encoding gene, DvJHAMT, in D. valens via bioinformatic analysis. RT-qPCR analysis revealed that DvJHAMT is predominantly expressed during the egg and larval stages. In the fourth-instar larvae, the highest expression levels were observed in the head and epidermis, suggesting a central regulatory role during this critical developmental period. To investigate its function via RNA interference (RNAi), a nanomaterial, star polycation (SPc), was employed for the transdermal delivery of dsRNA into the fourth-instar larvae. The results demonstrated that DvJHAMT knockdown significantly downregulated mRNA levels, resulting in marked decreases in larval survival, pupation, and eclosion rates. Notably, treatment with 0.7 µg dsDvJHAMT-SPc resulted in a 96.67% mortality rate and a reduced pupation rate of 41.67% at 34 days post-treatment. Furthermore, RNAi led to developmental deformities and significant weight loss in larvae. ELISA assays confirmed that DvJHAMT silencing led to reduced JHAMT enzyme activity and JH III titers in a dose-dependent manner. In conclusion, our findings demonstrate that DvJHAMT plays a vital role in JH biosynthesis and that its suppression exhibits potent lethal effects, suggesting that DvJHAMT is a promising candidate for RNAi-based management of D. valens. Full article

In sensing technologies, a hydrogel sensor with a specific response to stimuli allows for real-time monitoring of mechanical, thermal, and biochemical signals in wearable and implantable devices. This review discusses the latest advances in hydrogel-based sensors published between 2023 and spring 2026 and the design strategies prevalent in these articles, including the use of polymers, nanomaterial reinforcement, incorporation of ionic solvents, and physical or chemical crosslinking. The influence of supramolecular hydrogels on the quality of sensor parameters, including the impact on mechanical resistance, ionic conductivity, adaptation, and self-healing, is examined. In biomedical engineering, hydrogels, thanks to their biomimetic and programmable properties, enable control of wound repair and soft tissue interfaces. The review concludes by outlining the challenges, opportunities, and advances in the chemistry and mechanics of hydrogels, which may ultimately facilitate the development of multifunctional monitoring systems in healthcare. The abundance of information requires systematic, frequent reviews to accelerate the application of innovative solutions in practice. Carbon nanostructures are a key component that ensures the sensor’s electrical conductivity. 3D printing technology has enabled the creation of individually customizable health monitoring devices. The work also highlights the use of nanodots in sensor production. Full article

3D bioprinting technology has made great strides in the field of bone tissue engineering. It has been able to create personalized biological structures on a macroscopic scale. In terms of microstructure bionics, 3D printing technology has also made some progress in recent years. The use of nanotechnology and drug delivery technology has provided a microenvironment that is more compatible with cell growth. Finally, it is possible to bridge the gap between engineered organizational structures and natural tissues. In this work, we summarize the widely used 3D bioprinting methods and the preparation of bioinks. Next, the classification of bone tissue engineering scaffold materials and nanomaterials for loading is briefly introduced. Then the technical shortcomings of current nanotechnology-based 3D bioprinting are described, along with the corresponding improvements. Finally, we summarize the prospects of nano-based 3D bioprinting technology in bone tissue engineering. Full article