Search Results (2,346)

This study presents a comprehensive investigation into the large-scale production of synthetic and hybrid (nanoparticle-loaded) nanofibers using needleless electrospinning. A diverse range of polymers, including polyamide 6 (PA6) and its other polymer combinations, recycled PA6, polyamide 11 (PA11), polyamide 12 (PA12), polyvinyl butyral (PVB), polycaprolactone (PCL), polyacrylonitrile (PAN), polyvinylidene fluoride (PVDF), polyurethane (PU), polyvinyl alcohol (PVA), and cellulose acetate (CA), were utilized to fabricate nanofibers with tailored properties such as polymer solution concentrations and various solvent systems. Furthermore, an extensive variety of nano- and micro-particles, including TiO₂, ZnO, MgO, CuO, Ag, graphene oxide, CeO₂, Er₂O₃, WO₃, MnO₂, and hyperbranched polymers, were incorporated into the polymeric systems to engineer multifunctional nanofibers with enhanced structural characteristics. The study examines the impact of polymer–nano/micro-particle interactions, fiber morphology, and the feasibility of large-scale production via needleless electrospinning. The resulting nanofibers exhibited diameters starting from 80 nm, depending on the polymer and processing conditions. The incorporation of TiO₂, CeO₂, WO₃, Ag, and ZnO nanoparticles into 15% PA6 solutions yielded well-dispersed hybrid nanofibers. By providing insights into polymer selection, nano- and micro-particle integration, and large-scale production techniques, this work establishes a versatile platform for scalable hybrid nanofiber fabrication, paving the way for innovative applications in nanotechnology and materials science. Full article

Bacterial leaf blight (BLB), a destructive disease of rice caused by Xanthomonas oryzae pv. oryzae (Xoo), continues to limit rice productivity worldwide. Although biologically synthesized zinc oxide nanoparticles (ZnO NPs) have been extensively investigated, knowledge regarding the antibacterial activity and biocompatibility of commercially available ZnO NPs is still limited. In this study, commercial ZnO NPs were systematically characterized and evaluated for their antibacterial mechanisms and biocompatibility in mammalian cells. FE-SEM and TEM analyses revealed irregular polyhedral, hexagonal, and short rod-like morphologies with an average particle size of ~33 nm, consistent with crystallite sizes estimated by XRD. The nanoparticles exhibited pronounced antibacterial activity against Xoo, with a minimum inhibitory concentration (MIC) of 16 µg/mL and a clear dose-dependent response. Mechanistic assays confirmed multifaceted bactericidal actions involving membrane disruption, ROS generation, Zn²⁺ release, and ultrastructural damage. Biocompatibility testing in human dermal fibroblasts showed enhanced proliferation at 8–32 µg/mL, no cytotoxicity up to 256 µg/mL, and reduced viability only at ≥512 µg/mL. These findings represent the first mechanistic evaluation of commercial ZnO NPs against Xoo, together with cytotoxicity assessment in mammalian cells, highlighting their structural distinctness and dual functionality that combine potent antibacterial activity with minimal mammalian cytotoxicity. Overall, the results underscore their potential as safe nanobiocontrol agents for sustainable rice disease management. Full article

Diabetic foot ulcers (DFUs) are complex to heal and can lead to amputations and high healthcare costs. To address this, a promising alternative is the creation of electrospun fiber scaffolds for wound dressings. This study fabricated these scaffolds using a blend of natural polymers—chitosan (CTS), polyvinyl alcohol (PVA), and hyaluronic acid (HA)—along with antibacterial silver (Ag) and zinc oxide (ZnO) nanoparticles. The researchers conducted comprehensive analyses, including physicochemical, morphological, and biological assessments. The Ag structures showed potential as microbicidal agent, while the ZnO nanoparticles demonstrated photoactivity and the ability to generate reactive oxygen species (ROS) for antibacterial action. The resulting PVA-CTS-HA-Ag-ZnO scaffolds were found to be both hemocompatible and non-hemolytic, meaning they are safe for use with blood. The cytotoxicity evaluation using the ISO 10993-5 standard showed that the incorporation of CTS and HA decreased cytotoxicity of pure PVA, obtaining non-cytotoxic scaffolds (viability > 70%). Electrospun scaffolds composed with Ag-ZnO NPs in 50-50 and 70-30 ratios also maintained this biocompatibility, while the 30-70 ratio (Ag-ZnO) showed a cytotoxic effect, suggesting a ZnO concentration-dependent effect. These findings confirm that these materials are suitable for supporting skin cell regeneration, having a high potential for use as interactive dressings for treating chronic wounds. Full article

This study addresses the environmental challenge of end-of-life tire accumulation, a major source of toxic metals such as lead and cadmium in marine ecosystems. As a sustainable solution, multicomponent metal-oxide nanoparticles (Fe₃O₄, ZnO, CaO, MgO, and minor CaCO₃) were green-synthesized from sugarcane bagasse and stabilized with blackberry (Rubus glaucus) extract. Structural characterization (XRD, SEM, TEM, and EDS) confirmed their crystalline inorganic composition. Pb²⁺ was almost completely removed (95–99%) within 15–30 min using 50–100 mg of nanoparticles, with ~80–90% efficiency at 75 mg. Cd²⁺ removal showed dose-dependent kinetics: ~90% removal occurred within 10 min at 75 mg, while 50 and 100 mg reached ~60–70% after 60 min. Equilibrium, kinetic, and thermodynamic analyses revealed that Pb²⁺ adsorption followed the Langmuir model (R² = 0.982) with monolayer chemisorption, whereas Cd²⁺ obeyed the Freundlich model (R² = 0.945), indicating heterogeneous multilayer adsorption. Pb²⁺ removal fitted a pseudo-second-order model (R² = 0.991), while Cd²⁺ followed a pseudo-first-order behavior (R² = 0.958). Thermodynamic parameters (ΔG° < 0, ΔH° > 0, ΔS° > 0) confirmed a spontaneous and endothermic process. Sugarcane-bagasse-derived Fe₃O₄–ZnO–CaO–MgO nanomaterials act as sustainable and effective adsorbents for marine heavy metal removal. Full article

In response to the urgent need for sustainable antibacterial solutions against antibiotic-resistant pathogens, this study presents a facile dendritic polymer-assisted approach for synthesizing highly active ZnO/mesoporous silica nanocomposites (SBA-15, SBA-16, KIT-6, MSU-X). Two hyperbranched polymers—polyethyleneimine (PEI) and carboxy-methylated polyethyleneimine (Trilon-P, TrP)—were employed as templating and metal-trapping agents. The influence of pore geometry, polymer functionality, and polymer-loading method (wet or dry impregnation) on ZnO nanoparticle (NP) formation was systematically examined. All nanocomposites exhibited high structural homogeneity, incorporating ultrasmall or amorphous ZnO NPs (1–10 nm) even at 8 wt.% Zn loading. Zn uptake was strongly dependent on polymer end groups, while the spatial distribution of ZnO NPs was dictated by the silica host structure. Antibacterial assays against Staphylococcus aureus revealed remarkable activity, particularly for ZnO/SBA-15_PEI, ZnO/SBA-16_PEI, and ZnO/MSU-X_TrP nanocomposites, with minimum inhibitory concentrations of 1–2.5 μg mL⁻¹ Zn and over 90% mammalian cell viability. Life Cycle Assessment identified energy use as the main environmental factor, with ZnO/SBA-15_PEI_WI displaying the lowest impact. Overall, the interplay between silica pore architecture, polymer type, and impregnation method governs ZnO accessibility and bioactivity, establishing a versatile strategy for designing next-generation ZnO/SiO₂ nanocomposites with tunable antibacterial efficacy and minimal cytotoxic and environmental footprint. Full article

Salt stress is a major form of abiotic stress that disrupts soybean germination and early seedling establishment. In this study, physiological, biochemical, and transcriptomic analyses—including germination index, antioxidant enzyme activity, and RNA-seq profiling—were conducted during soybean germination to elucidate early responses to salt stress and biostimulant treatment. A preliminary screening of six biostimulants (nanoparticle zinc oxide (NP-ZnO), nanoparticle silicon dioxide (NP-SiO₂), silicon dioxide (SiO₂), glucose, humic acid, and fulvic acid) revealed NP-SiO₂ as the most effective in promoting germination under salt stress. Under 150 mM NaCl, NP-SiO₂ increased the germination rate and length of the radicle compared with the control, also enhancing peroxidase and ascorbate peroxidase activities while reducing malondialdehyde accumulation, suggesting alleviation of oxidative stress. RNA sequencing revealed extensive transcriptional reprogramming under salt stress, identifying 4579 differentially expressed genes (DEGs) compared with non-stress conditions, while NP-SiO₂ treatment reduced this number to 2734, indicating that NP-SiO₂ mitigated the transcriptional disturbance caused by salt stress and stabilized gene expression networks. Cluster analysis showed that growth- and hormone-related genes suppressed by salt stress were restored under NP-SiO₂ treatment, whereas stress-responsive genes that were induced by salt were attenuated. Hormone-related DEG analysis revealed that NP-SiO₂ down-regulated the overactivation in the abscisic acid, jasmonic acid, and salicylic acid pathways while partially restoring gibberellin, auxin, cytokinin, and brassinosteroid signaling. Overall, NP-SiO₂ at 100 mg/L mitigated salt-induced oxidative stress and promoted early soybean growth by fine-tuning physiological and transcriptional responses, representing a promising nano-based biostimulant for enhancing salt tolerance in plants. Full article

The success of plant tissue cryopreservation strongly depends on maximizing explant survival during storage in liquid nitrogen and recovery, which requires species-specific protocol optimization and ongoing refinement. This study examined the effect of Plant Vitrification Solution 3 (PVS3) supplemented with nanoparticles (NPs) or melatonin (MEL) on the recovery of Lamprocapnos spectabilis (L.) Fukuhara explants after cryostorage. Treatments with ZnO + Ag NPs, as well as different MEL concentrations, were applied to evaluate their influence on explant survival, photosynthetic efficiency, and genetic stability. The highest recovery (40–44%) was obtained with PVS3 containing 50 mg L⁻¹ ZnO + 0.1% Ag NPs and PVS3 supplemented with 8 mg L⁻¹ MEL, which was 17.5–20% higher than in the control. These treatments, however, did not ensure the highest photosynthetic efficiency of recovered plants. PVS additives likely support recovery by slowing metabolism and reducing oxidative stress, with lower photosynthetic activity suggesting a lag phase in plastid regeneration. Using the Start Codon Targeted (SCoT) marker system, no significant genetic alterations were detected in recovered plants of any tested variant. These findings demonstrate the feasibility of optimizing cryopreservation protocols for L. spectabilis and encourage further research on combined NPs and MEL treatments or alternative nanocarriers. Full article

This study aimed to synthesize zinc oxide nanoparticles (ZnO-NPs) via a green sustainable approach using Raphanus sativus (L.) root extract and evaluate their gastroprotective effect against ethanol-induced gastric injury in rats. ZnO-NPs were characterized through UV–Vis spectroscopy, FT-IR, TEM, zeta potential analysis, and XRD. LC- MS-coupled metabolic profiling was employed to identify different phytochemical compounds in the plant. Oxidative stress biomarkers (GSSG, GPX, and CAT), gastric secretions (gastrin and histamine), inflammatory cytokines (TNF-α and NF-κB), and molecular markers (MMP-10 and pERK1/2) were evaluated. Treatment with ZnO-NPs and plant extract restored antioxidant enzyme activity in a dose-dependent manner and decreased oxidative and inflammatory markers. Histopathological and histochemical analyses confirmed the protection of the gastric mucosa. The ZnO-NPs at (200 mg/kg), showed superior efficacy over the extract and, in some cases, displayed equivalent or enhanced effects relative to the reference drug omeprazole. In silico findings support the gastroprotective potential of the plant by demonstrating strong binding associations for major phytochemicals. This paper highlights that green-synthesized ZnO-NPs exhibit a significant gastroprotective effect through the modulation of oxidative stress and inflammatory pathways, indicating their promise as a safe and effective alternative treatment for gastric ulcers. Full article

Titanium dioxide nanoparticles were synthesized via hydrothermal treatment of tetrabutyl titanate in sulfuric acid, with controlled reaction times (10 h and 24 h) and zinc sulfate as a modifier. XRD confirmed exclusive formation of the anatase phase, with longer reaction times promoting crystallite growth. SEM and BET analyses showed that introducing Zn during synthesis suppressed agglomeration, decreased the particle size, and modified porosity while maintaining the mesoporous nature of all samples. UV–Vis diffuse reflectance spectroscopy showed a band gap near 3.2 eV, which was unaffected by Zn content or morphology. Photoconductivity studies showed a several-orders-of-magnitude increase in conductivity under vacuum conditions, especially in samples heat-treated for 24 h, due to the generation of oxygen vacancies and ${\mathrm{Ti}}^{3+}$ states that prolong the carrier lifetime. In particular, the TS24Z8 sample exhibited a photoconductivity enhancement of five orders of magnitude relative to its dark conductivity and nearly 30 times higher than that of the commercial P25 benchmark. In contrast, in air, photoconductivity remained low because of strong surface recombination with adsorbed oxygen. These results emphasize the critical influence of hydrothermal duration and zinc incorporation on the defect structure and electronic response of ${\mathrm{TiO}}_2$, offering insights for improved photocatalytic and optoelectronic applications. Full article

Enhancing the oxidation resistance of copper nanoparticles (CuNPs) is a crucial objective in plasmonic photocatalytic reactions. In this study, a series of Cu/X catalysts was synthesized using semiconductor nanomaterials (X = TiO₂, ZnO, BN, TiN, SiC, and C₃N₄) as supports for CuNPs. These catalysts were systematically evaluated in visible-light-driven photocatalytic oxidative homocoupling of phenylacetylene (OHA). Comprehensive characterization revealed distinct metal-support interactions and nanostructure evolution during repeated catalytic cycles. The photocatalytic performance, copper leaching, and structural stability of the catalysts were compared. Cu/TiO₂ achieved the highest 1,3-diyne yield (up to 93%) in the first two cycles. In contrast, Cu/ZnO showed minimal copper leaching and excellent recyclability, retaining high activity over three consecutive cycles without the need for reduction pretreatment. Comparative studies revealed that the combination of localized surface plasmon resonance (LSPR) and efficient electron transfer within the Cu⁰-Cu₂O-CuO composite was a key factor in enhancing the photocatalytic activity and stability. These findings provide new insights into the rational design of durable CuNP-based photocatalysts for visible-light-driven organic transformations. Full article

Although fast-paced ongoing industrial growth, on the one hand, enhances the lifestyle of the population, on the other hand, it affects human health and the environment as a result of the discharge of pollutants. To address this, designing a novel and effective photocatalyst is necessary to mitigate increasing environmental pollutants. In the present work, we aim to synthesize a single-phase high-entropy zirconate pyrochlore oxide (Ce_0.2Pr_0.2Zn_0.2Nd_0.2Tb_0.2)₂Zr₂O₇ using a modified Pechini method. The physicochemical properties of the prepared nanoparticles were investigated using X-ray diffraction, UV-visible spectroscopy, field emission scanning electron microscopy, and X-ray photoelectron spectroscopy. The photocatalytic properties were examined using cationic dye (methylene blue), anionic dye (Congo red), and Cr(VI). Photocatalytic degradation experiments demonstrate exceptional efficiency in the removal of persistent organic pollutants. The photocatalytic results indicate that the prepared high-entropy (Ce_0.2Pr_0.2Zn_0.2Nd_0.2Tb_0.2)₂Zr₂O₇ zirconate pyrochlore oxide could effectively degrade dyes and reduce Cr(VI). Radical trapping experiments indicate that the degradation of dyes was driven by the hydroxyl radicals, superoxide radicals, and holes. Furthermore, the position of the valence band and conduction band promoted efficient photocatalytic reaction kinetics. The prepared photocatalyst remains structurally stable and can be reused three times without losing activity. Full article

The development of bioactive dental materials with antimicrobial and biocompatible properties is important for improving clinical outcomes and reducing complications associated with intraoral devices. This study presents a novel approach that combines a 3D-printed shape-memory resin (TC-85DAC) with green-synthesized zinc oxide nanoparticles (ZnO NPs) to enhance biological performance. ZnO NPs were synthesized using Dysphania ambrosioides extract, producing quasi-spherical particles with a crystalline hexagonal structure and sizes between 15 and 40 nm. Resin discs were coated with ZnO NPs at 10%, 20%, and 30%, then assessed for biocompatibility with human gingival fibroblasts and antibacterial activity against Porphyromonas gingivalis and Streptococcus mutans. Surface roughness was also considered with and without ZnO NPs. Biocompatibility assays revealed a concentration- and time-dependent increase in cell viability, with the highest values at 30% ZnO NPs after 72 h of exposure to the NPs. Antibacterial testing confirmed the inhibition of both species, with Porphyromonas gingivalis showing greater sensitivity. Surface roughness increased with higher ZnO NPs concentrations, significantly influencing biological interactions. The integration of green-synthesized ZnO NPs with shape-memory resin produced a multifunctional dental material with improved bioactivity. This sustainable strategy enables bioactive coatings on 3D-printed resins, with potential applications in the next generation of smart dental devices. Full article

Cell population and vascular vessel distribution analysis in membrane-based scaffolds for tissue engineering is crucial. Biomimetic nanostructured membranes of methyl methacrylate/hydroxyethyl methacrylate and methyl acrylate/hydroxyethyl acrylate (MMA)1-co-(HEMA)1/(MA)3-co-(HEA)2 loaded with 5% wt SiO2-nanoparticles (Si-M) were doped with zinc (Zn-M) or doxycycline (Dox-M). Critical bone defects were effectuated on six New Zealand-bred rabbit skulls and then they were covered with the membrane-based scaffolds. After six weeks, bone cell population in terms of osteoblasts, osteoclasts, osteocytes, fibroblasts, and M1 and M2 macrophages and vasculature was determined. The areas of interest were the space above (over) and below (under) the membrane, apart from the interior (inner) compartment. All membranes showed that vasculature and most cell types were more abundant under the membrane than in the inner or above regions. Quantitatively, osteoblast density increased by approximately 35% in Zn-M and 25% in Si-M compared with Dox-M. Osteoclast counts decreased by about 78% in Dox-M, indicating strong inhibition of bone resorption. Vascular structures were nearly twofold more frequent under the membranes, particularly in Si-M, while fibroblast presence remained moderate and evenly distributed. The M1/M2 macrophage ratio was higher in Zn-M, reflecting a transient pro-inflammatory state, whereas Dox-M favored an anti-inflammatory, pro-regenerative profile. These results indicate that the biomimetic electrospun membranes functioned as architectural templates that provided favorable microenvironments for cell colonization, angiogenesis, and early bone regeneration in a preclinical in vivo model. Zn-M membranes appear suitable for early osteogenic stimulation, while Dox-M membranes may be advantageous in clinical contexts requiring modulation of inflammation and osteoclastic activity. Full article

Metal–organic frameworks (MOFs) are promising materials for environmental remediation, particularly in photocatalysis. In this work, a novel ZMIP nanocomposite was fabricated by integrating MIP-202(Zr) bio-MOF with ZnO nanoparticles. For the first time, ZnO nanoparticles were green-synthesized using water lettuce extract and incorporated into MIP-202(Zr) via a mild hydrothermal route. The resulting hybrid was applied as a visible-light photocatalyst for carbamazepine (CBZ) degradation in real pharmaceutical wastewater. Structural analyses (XRD, FTIR, TEM, EDS) verified the successful incorporation of ZnO into the MIP-202(Zr) framework. The composite exhibited a narrowed bandgap of 2.74 ± 0.1 eV compared to 4.05 ± 0.06 eV for pristine MIP-202 and 3.77 ± 0.04 eV for ZnO, highlighting enhanced visible-light utilization in ZMIP. Operational parameters were optimized using response surface methodology, where CBZ removal reached 99.37% with 84.39% TOC mineralization under the optimal conditions (90 min, pH 6, 15 mg/L CBZ, 1.25 g/L catalyst). The catalyst maintained stable performance over five reuse cycles. Radical quenching and UHPLC-MS analyses identified the dominant reactive oxygen species and generated intermediates, elucidating the degradation mechanism and pathways. Beyond CBZ, the ZMIP photocatalyst effectively degraded other pharmaceuticals, including doxorubicin, tetracycline, paracetamol, and ibuprofen, achieving degradation efficiencies of 82.93%, 76.84%, 72.08%, and 67.71%, respectively. Application on real pharmaceutical wastewater achieved 78.37% TOC removal under the optimum conditions. Furthermore, the supplementation of the photocatalytic system by inorganic oxidants ameliorated the degradation performance, following the order KIO₄ > K₂S₂O₈ > KHSO₅ > H₂O₂. Overall, ZMIP demonstrates excellent activity, reusability, and versatility, underscoring its potential as a sustainable photocatalyst for real wastewater treatment. Full article

The increasing demand for sustainable construction materials has prompted the recycling of construction and demolition waste in concrete manufacturing. This study investigates the feasibility of utilizing porcelain and brick waste as partial substitutes for natural sand in concrete with the objective of improving sustainability and preserving mechanical and durability characteristics. The experimental program was conducted in three consecutive phases. During the initial phase, natural sand was partially substituted with porcelain waste powder (PWP) and brick waste powder (BWP) in proportions of 25%, 50%, and 75% of the weight of the fine aggregate. During the second phase, polypropylene fibers were mixed at a dosage of 0.5% by volume fraction to enhance tensile and flexural properties. During the third phase, zinc oxide nanoparticles (ZnO-NPs) were utilized as a partial substitute for cement at concentrations of 0.5% and 1% to improve microstructure and strength progression. Concrete samples were tested at curing durations of 7, 28, and 91 days. The assessed qualities encompassed workability, density, water absorption, porosity, compressive strength, flexural strength, and splitting tensile strength. Microstructural characterization was conducted utilizing X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The findings indicated that porcelain waste powder markedly surpassed brick waste powder in all mechanical and durability-related characteristics, particularly at 25% and 50% sand replacement ratios. The integration of polypropylene fibers enhanced fracture resistance and ductility. Moreover, the incorporation of zinc oxide nanoparticles improved hydration, optimized the pore structure, and resulted in significant enhancements in compressive and tensile strength throughout prolonged curing durations. The best results were obtained with a mix of 50% porcelain sand aggregate, 1% zinc oxide nanoparticles as cement replacement, and 0.5% polypropylene fibers, for which the improvements in compressive strength, flexural strength, and splitting tensile strength were 39.5%, 46.2%, and 60%, respectively, at 28 days. The results confirm the feasibility of using porcelain and brick waste as sand replacements in concrete, as well as polypropylene fiber-reinforced concrete and polypropylene fiber-reinforced concrete mixed with zinc oxide nanoparticles as a sustainable option for construction purposes. Full article