Search Results (343)

Background/Objectives: Chitosan-based films incorporating green-synthesized silver nanoparticles AgNPs) or copper oxide nanoparticles (CuONPs) were developed to compare their selective antimicrobial action for topical applications. While AgNPs are known for broad-spectrum activity, this study hypothesized that CuONPs would exhibit superior, targeted efficacy against the acne-associated bacterium Cutibacterium acnes. Methods: Nanoparticles were synthesized using Camellia sinensis extract and characterized. Antimicrobial activity was evaluated using Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) assays. Chitosan films containing AgNPs or CuONPs were further tested for selective antimicrobial activity and fibroblast cytocompatibility. Results: AgNPs showed strong activity against Escherichia coli and Staphylococcus aureus (MIC = 15 µg/mL) but were less effective against C. acnes (MIC = 125 µg/mL). In contrast, CuONPs demonstrated selective efficacy against C. acnes (MIC = 62 µg/mL; MBC = 125 µg/mL). When incorporated into chitosan films, AgNPs@CHI inhibited E. coli (35 mm halo) and S. aureus (30 mm), whereas CuONPs@CHI were selectively effective against C. acnes (45 mm). All films preserved fibroblast viability above the 70% ISO 10993-5 threshold. Conclusions: CuONPs@CHI films validated selective anti-C. acnes performance, highlighting their promise for targeted anti-acne therapies, while AgNPs@CHI films served as effective broad-spectrum antimicrobial barriers.revealed that AgNPs were potent against Escherichia coli and Staphylococcus aureus (MIC = 15 µg/mL) but less effective against C. acnes (MIC = 125 µg/mL). Conversely, CuONPs demonstrated a marked selective advantage against C. acnes (MIC = 62 µg/mL; MBC = 125 µg/mL). When incorporated into chitosan films, AgNPs@CHI films inhibited E. coli (35 mm halo) and S. aureus (30 mm), whereas CuONPs@CHI films were selectively effective only against C. acnes (45 mm), confirming the targeted performance. All films maintained fibroblast viability above the 70% ISO 10993-5 cytotoxicity threshold. These findings validate the selective action of CuONPs@CHI films, positioning them as a promising biomaterial for targeted anti-acne therapies, while AgNPs@CHI films serve as effective broad-spectrum antimicrobial barriers. Full article

Esophageal squamous cell carcinoma (ESCC) accounts for the majority of esophageal cancers worldwide, with a poor prognosis and increasing resistance to conventional treatments. Faced with these limitations, nanoparticles (NPs) are attracting growing interest as innovative therapeutic agents capable of improving specificity and efficacy and reducing systemic toxicity. This study critically examines the pharmacological effects, mechanisms of action, and toxicity profiles of different metallic or organic nanoparticles tested on ESCC cell lines. Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 guidelines were followed by a meticulous literature search of Google Scholar, Web of Science, PubMed/Medline, and Scopus databases to achieve this goal. The results show that the anti-tumor properties vary according to the type of nanoparticle (copper(II) oxide (CuO), silver (Ag), gold (Au), nickel(II) oxide (NiO), nano-curcumin, etc.), the synthesis method (chemical vs. green), and the biological activity assessment method (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), Bromodeoxyuridine (BrdU), Cell Counting Kit-8 (CCK8) assays, etc.). NPs derived from green synthesis, such as those based on Moringa oleifera, Photinia glabra, or pomegranate bark, exhibit moderate cytotoxic activity (50% inhibitory concentration (IC₅₀) between 92 and 500 µg/mL) but show good tolerance on normal cells. In contrast, chemically synthesized NPs, such as Cu(II) complexes with 1,3,5-benzenetricarboxylic acid (H₃btc) or 1,2,4-triazole (Htrz), show lower IC₅₀ (34–86 µM), indicating more marked cytotoxicity towards cancer cells, although data on their toxicity are sometimes lacking. In addition, multifunctional nanoparticles, such as gold-based nano-conjugates targeting Cluster of Differentiation 271 (CD271) or systems combined with doxorubicin, show remarkable activity with IC₅₀ below 3 µM and enhanced tumor selectivity, positioning them among the most promising candidates for future clinical application against ESCC. The most frequently observed mechanisms of action include induction of apoptosis (↑caspases, ↑p53, ↓Bcl-2), oxidative stress, and inhibition of proliferation. In conclusion, this work identifies several promising nanoparticles (silver nanoparticles derived from Photinia glabra (PG), gold-based nano-immunoconjugates targeting CD271, and silver–doxorubicin complexes) for future pharmaceutical exploitation against ESCC. However, major limitations remain, such as the lack of methodological standardization, insufficient in vivo and clinical studies, and poor industrial transposability. Future prospects include the development of multifunctional nanocomposites, the integration of biomarkers for personalized targeting, and long-term toxicological assessment. Full article

Background: The bacterial wilt of tomatoes, caused by Ralstonia solanacearum, is a soil-borne plant disease that causes substantial agricultural economic losses. Various nanoparticles have been utilized as antibacterial agents to mitigate pathogenic destructiveness and improve crop yields. However, there is a lack of in-depth research on how nanoparticles affect tomato metabolite levels to regulate the bacterial wilt of tomatoes. Methods: In this study, healthy and bacterial wilt-infected tomatoes were treated with Cu-Ag nanoparticles, and a metabolomics analysis was carried out. Results: The results showed that Cu-Ag nanoparticles had a significant prevention and control effect on the bacterial wilt of tomatoes. Metabolomic analysis revealed that the nanoparticles could significantly up-regulate the expression levels of terpenol lipids, organic acids, and organic oxygen compounds in diseased tomatoes, and enhance key metabolic pathways such as amino acid metabolism, carbohydrate metabolism, secondary metabolite metabolism, and lipid metabolism. These identified metabolites and pathways could regulate plant growth and defense against pathogens. Correlation analysis between the tomato microbiome and metabolites showed that most endophytic microorganisms and rhizospheric bacteria were positively correlated with fatty acyls groups and organic oxygen compounds. Conclusions: This study reveals that Cu-Ag nanoparticles can actively regulate the bacterial wilt of tomatoes by up-regulating the levels of lipid metabolism and organic oxygen compounds, providing an important theoretical basis for the application of nanoparticles in agriculture. Full article

Chitosan is a natural biopolymer with intrinsic antimicrobial properties and strong metal ion chelating properties, making it an ideal matrix for the development of bioactive composites. In this study, silver and copper nanoparticles were synthesized using laser ablation in liquid (LAL) by the ablation of metallic targets into commercial chitosan (Cs) and chitosan produced from Hermetia illucens pupal exuviae (CsE) solutions, avoiding the use of chemical precursors or stabilizing agents. The nanocomposites obtained were characterized by UV–vis spectroscopy, TEM microscopy and FTIR spectroscopy in order to evaluate the size of the nanoparticles and the interactions between the polymer and metal nanoparticles. Antibacterial tests demonstrated the efficacy of Ag-based composites with a minimum inhibitory concentration (MIC) of 0.006 g/L, and Cu-based composites with a MIC of 0.003 g/L against both Escherichia coli and Micrococcus flavus. While the silver composites show antibacterial activity in both colloidal and film forms, the copper composites present antibacterial activity only in colloidal form. Swelling tests indicated that all films maintained a high water absorption capacity, with a swelling index over 200%, unaffected by nanoparticle integration. The results highlight the potential of LAL-synthesized metal–chitosan composites, particularly those based on insect chitosan, as sustainable and effective antimicrobial materials for biomedical and environmental applications. Full article

The increasing integration of physical and nanotechnological treatments in agriculture has unlocked new possibilities for enhancing seed performance and the functional properties of seedlings. This study aimed to determine the effect of the coupled use of pulsed electric field (PEF) and the soaking (coating) of sunflower seeds in metal nanoparticles (AgNP and CuNP) on their germination capacity and on the stem and root length, content of pigments (chlorophyll a, chlorophyll b, carotenoids), color profile, and antioxidative properties (FRAP, polyphenols, TPC, ABTS, and DPPH) of sunflower seedlings. The study results enable the drawing of explicit conclusions that the higher PEF energy applied (5.5 kJ kg⁻¹) and seed treatment with nanoparticle solutions, in most cases, diminished the germination capacity of sunflower seeds (from 3.50 to 44.11%) compared to the control samples. A decreased seedling stem length was determined at both PEF energy levels tested, i.e., 1 kJ kg⁻¹ and 5.5 kJ kg⁻¹, with the values obtained being 11.86% to 46.14% lower compared to the respective control samples. The root length of the seedlings decreased as well, i.e., by 7.34 to 41%. The content of chlorophyll a (chl a) increased in the seedlings from all experimental variants compared to the control, whereas that of chlorophyll b (chl b) decreased by 3.24 to 7.86% in the control variant with PEF and CuNP. The FRAP value, total content of polyphenols, and TPC ranged from 10.20 to 12.95 (mg TE g⁻¹ DM), from 42.23 to 49.19 (mg GAE g⁻¹ DM), and from 20.20 to 23.90 (mg GAE g⁻¹ DM), respectively, and showed an upward trend compared to the control samples. The results of this study indicate that further research is needed to understand how the analyzed treatments affect seedling growth and demonstrate reduced germination capacity and enhanced antioxidant activity due to the synergistic effect of a high PEF and nanoparticle solutions. Full article

The growing prevalence of bacteria resistant to antibiotics and conventional disinfectants is a cause for concern and underscores the necessity of developing new strategies to prevent the transmission of microorganisms. To this end, nanocrystalline Cu, Au, and Ag nanoparticles were employed to fabricate various coatings using the sputtering technique. Then, the antibacterial activity of the coatings against Gram-negative Escherichia coli and Gram-positive Staphylocococcus epidermidis was investigated. The coating obtained by co-sputtering of Au, Ag, and Cu exhibited the most pronounced antibacterial properties. This coating was applied to disposable BIC ballpoint pens, which were subsequently used by clients in two public institutions. After three months of regular use, the antibacterial properties of the coatings were re-evaluated. It was confirmed that this coating led to a significant reduction (log5 CFU/mL) in the bacterial presence on the treated surface within 0.5 h. These results support further investigation into the underlying mechanism, which is likely based on the synergistic interaction of the employed noble metal nanoparticles. Full article

Mesenchymal stem cells (MSCs), i.e., adult stem cells with immunomodulatory and secretory properties, contribute to tissue growth and regeneration, including healing processes. Some metal nanoparticles (NPs) are known to exhibit antimicrobial activity and may further potentiate tissue healing. We studied the effect of Ag, CuO, and ZnO NPs after in vitro exposure of mouse MSCs at the transcriptional level in order to reveal the potential toxicity as well as modulation of other processes that may modify the activity of MSCs. mRNA–miRNA interactions were further investigated to explore the epigenetic regulation of gene expression. All the tested NPs mediated immunomodulatory effects on MSCs, generation of extracellular vesicles, inhibition of osteogenesis, and enhancement of adipogenesis. Ag NPs exhibited the most pronounced response; they impacted the expression of the highest number of mRNAs, including those encoding interferon-γ-stimulated genes and genes involved in drug metabolism/cytochrome P450 activity, suggesting a response to the potential toxicity of Ag NPs (oxidative stress). Highly interacting MiR-126 was upregulated by all NPs, while downregulation of MiR-92a was observed after the ZnO NP treatment only, and both effects might be associated with the improvement of MSCs’ healing potency. Overall, our results demonstrate positive effects of NPs on MSCs, although increased oxidative stress caused by Ag NPs may limit the therapeutical potential of the combined MSC+NP treatment. Full article

Environmental sustainability and responsible resource utilization are critical global challenges. In this work, we present a sustainable and circular-economy-based approach for synthesizing CuFe₂O₄ nanoparticles by directly utilizing copper oxide minerals sourced from Chilean mining operations. Copper sulfate (CuSO₄) was extracted from these minerals through acid leaching and used as a precursor for nanoparticle synthesis via both chemical co-precipitation and microwave-assisted methods. The influence of different precipitating agents—NaOH, Na₂CO₃, and NaF—was systematically evaluated. XRD and FESEM analyses revealed that NaOH produced the most phase-pure and well-dispersed nanoparticles, while NaF resulted in secondary phase formation. The microwave-assisted method further improved particle uniformity and reduced agglomeration due to rapid and homogeneous heating. Electrochemical characterization was conducted to assess the suitability of the synthesized CuFe₂O₄ for supercapacitor applications. Cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) measurements confirmed pseudocapacitive behavior, with a specific capacitance of up to 1000 F/g at 2 A/g. These findings highlight the potential of CuFe₂O₄ as a low-cost, high-performance electrode material for energy storage. This study underscores the feasibility of converting primary mined minerals into functional nanomaterials while promoting sustainable mineral valorization. The approach can be extended to other critical metals and mineral residues, including tailings, supporting the broader goals of a circular economy and environmental remediation. Full article

Tomatoes are a fundamental part of the daily diet, rich in carbohydrates, vitamins, minerals, carotenoids, and polyphenols. Nonetheless, optimal fruit yield and quality typically depend on the application of synthetic agrochemicals. However, the irrational use of these agrochemicals has caused various environmental problems. Therefore, it is necessary to develop alternatives to conventional agrochemical products. Applying nanomaterials as fertilizers in tomato production is emerging as a promising approach, with documented improvements in germination, vegetative development, and fruit yield. Therefore, we present a comprehensive review of recent developments (2015–2024) in the application of nanomaterials in tomato crops, with a particular emphasis on the significance of nanomaterial characteristics in their role as fertilizers. Several types of nanomaterials, such as ZnO, Ag, TiO₂, Si, hydroxyapatite, P, Zn, Se, CuO, Cu, Fe, Fe₂O₃, CaO, CaCO₃, and S, have been evaluated as fertilizers for tomato crops, with ZnO nanoparticles being the most extensively studied. However, it is pertinent to conduct further research on the less-explored nanomaterials to gain a deeper understanding of their effects on seed germination, plant growth, and fruit quality and quantity. Full article

The regulation of the active sites of a catalyst is important for its application. Herein, a series of Ag₁Cu_x/SBA-15 catalysts with different molar ratios of Ag to Cu were synthesized via the impregnation method, and the active sites of Ag₁Cu_x were regulated via various pretreatment conditions. These as-prepared Ag₁Cu_x/SBA-15 catalysts were characterized by many technologies, and their catalytic performance was estimated through CO catalytic oxidation. Among these catalysts, Ag₁Cu_0.025/SBA-15, with a Ag/Cu molar ratio of 1:0.025 and pretreated under the condition of 500 °C O₂/Ar for 2 h, followed by 300 °C H₂ for another 2 h, presented optimal CO degradation performance, which could realize the oxidation of 98% CO at 34 °C (T₉₈ = 34 °C). Meanwhile, Ag₁Cu_0.025/SBA-15 also displayed great reusability. Characterization results, such as X-ray diffraction (XRD), ultraviolet–visible diffuse reflectance spectra (UV-vis DRS), temperature-programmed H₂ reduction (H₂-TPR), and physical adsorption, suggested that the optimal catalytic performance of Ag₁Cu_0.025/SBA-15 was ascribed to its high interspersion of Ag nanoparticles, better low-temperature reduction ability, the interaction between Ag and Cu, and its high surface area and large pore volume. This study provides guidance for the regulation of active sites for low-temperature catalytic degradation. Full article

The growing prevalence of bacterial infections and the alarming rise of antimicrobial resistance (AMR) have driven the need for innovative antimicrobial coatings for medical implants and biomaterials. However, implant surface properties, such as roughness, chemistry, and reactivity, critically influence biological interactions and must be engineered to ensure biocompatibility, corrosion resistance, and sustained antibacterial activity. This review evaluates three principal categories of antimicrobial agents utilized in surface functionalization: metal/metaloxide nanoparticles, antibiotics, and phytochemical compounds. Metal/metaloxide-based coatings, especially those incorporating silver (Ag), zinc oxide (ZnO), and copper oxide (CuO), offer broad-spectrum antimicrobial efficacy through mechanisms such as reactive oxygen species (ROS) generation and bacterial membrane disruption, with a reduced risk of resistance development. Antibiotic-based coatings enable localized drug delivery but often face limitations related to burst release, cytotoxicity, and diminishing effectiveness against multidrug-resistant (MDR) strains. In contrast, phytochemical-derived coatings—using bioactive plant compounds such as curcumin, eugenol, and quercetin—present a promising, biocompatible, and sustainable alternative. These agents not only exhibit antimicrobial properties but also provide anti-inflammatory, antioxidant, and osteogenic benefits, making them multifunctional tools for implant surface modification. The integration of these antimicrobial strategies aims to reduce bacterial adhesion, inhibit biofilm formation, and enhance tissue regeneration. By leveraging the synergistic effects of metal/metaloxide nanoparticles, antibiotics, and phytochemicals, next-generation implant coatings hold the potential to significantly improve infection control and clinical outcomes in implant-based therapies. Full article

Vegetable crops such as tomato are highly susceptible to various pathogens. Nanoparticles (NPs) are emerging as effective nano-bactericides for managing plant pathogens. Communities of rhizosphere bacteria are essential for plant physiological health and also serve as a critical factor in evaluating the environmental compatibility of NPs. We evaluated the effects of a nano-bactericide (Cu-Ag nanoparticles) and a commercial bactericide (thiodiazole–copper) on the rhizosphere microbiome of tomato. The results show that low and high doses of the two bactericides induced alterations in the bacterial community structure to differing extents. Cu-Ag nanoparticles increased the relative abundance of potentially beneficial bacteria, including Bacteroidota, Gemmatimonadota, Acidobacteriota, and Actinobacteriota. Functional prediction revealed that Cu-Ag nanoparticles may affect the metabolic pathways of tomato root rhizosphere microorganisms and regulate the lacI/galR family, which controls virulence factors and bacterial metabolism. This study provides insight into the influence of metal nanoparticles on plant rhizosphere microbiomes and may lay a foundation for the application of nano-bactericides for the environmentally friendly control of plant diseases. Full article

Bacterial leaf blight (BLB) is a destructive disease caused by Xanthomonas oryzae pv. oryzae (Xoo). It has been proven that BLB adversely influences the growth and production of rice, resulting in substantial losses in yield. Nanoparticle–antimicrobial compounds possess excellent physicochemical properties, which have generated groundbreaking applications in protecting rice against BLB attacks. However, there is less research focused on the interaction between nanoparticles and the microbiome of BLB rice leaves, particularly the structure and function of endophytic bacteria, which are essential to plant health and pathogenesis. Therefore, the study explored how Cu-Ag nanoparticles influenced the endophytic bacteria’s composition and functions in healthy and BLB rice leaves. The data demonstrated that the relative abundance of beneficial bacteria, Burkholderiales, Micrococcales, and Rhizobiales, increased after the introduction of Cu-Ag nanoparticles on the leaves of BLB rice. The examination of PAL activity demonstrated that nanoparticles limited the spread of Xoo in rice leaves. Furthermore, endophytic community functional prediction demonstrated that nanoparticles may regulate the physiological process associated with potential stress resistance and growth-promoting function in the endophytic communities. This investigation may enhance the understanding of interactions between nanoparticles and the composition of rice endophytic microbiome, which can contribute to the exploration and application of nanomaterials in crop pathogen management. Full article

Non-radiative decay of surface plasmon (SP) offers a novel paradigm for efficient conversion of photons into carriers. However, the narrow bandwidth of SP has been a significant obstacle to the widespread applications. Previously, research and applications mainly focused on noble metals such as Au, Ag, and Cu. In this article, we report an Ag-Al alloy material, μ-Ag₃Al, in which the surface plasmon operating bandwidth is 1.7 times that of Ag and hot carrier transport properties are comparable with those of AuAl. The results show that μ-Ag₃Al allows efficient direct interband electronic transitions from ultraviolet (UV) to near infrared range. Spherical nanoparticles of μ-Ag₃Al exhibit the localized surface plasmon resonance (LSPR) effect in the ultraviolet region. Its surface plasmon polariton (SPP) shows strong non-radiative decay at 3.36 eV, which is favorable for the generation of high-energy hot carriers. In addition, the penetration depth of SPP in μ-Ag₃Al remains high across the UV to the near-infrared range. Moreover, the transport properties of hot carriers in μ-Ag₃Al are comparable with those in Al, borophene and Au-Al intermetallic compounds. These properties can provide guidance for the design of plasmon-based photodetectors, solar cells, and photocatalytic reactors. Full article

Bacterial infections are the primary cause of mastitis in dairy cattle. Fungal mastitis occurs in 1–12% of cases. Antibiotic therapy, the standard treatment for mastitis, has led to antibiotic-resistant bacteria, reducing treatment efficacy and increasing fungal mastitis occurrence. Antibiotics lack biocidal effects on fungi, which often exhibit resistance to antifungal agents. This study evaluated the antifungal properties of nanoparticles (NPs) against Candida albicans, Candida glabrata, Candida parapsilosis, Diutina rugosa var. rugosa, Diutina catenulata, and Diutina rugosa. Tested NPs included gold (AuNPs), silver (AgNPs), copper (CuNPs), iron with hydrophilic carbon coating (FeCNPs) (1.56–25 mg/L), and platinum (PtNPs) (0.625–10 mg/L), along with their complexes. Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) at 0.75–25 mg/L for AuNPs, AgNPs, CuNPs, and FeCNPs and 0.313–10 mg/L for PtNPs, as well as fungal sensitivity to standard antifungals, were determined. Each strain showed different sensitivities depending on the NPs used and their concentrations. C. glabrata was the most resistant to nanoparticles, while D. catenulata was the most susceptible. PtNPs and FeCNPs showed no or weak biocidal properties. Some mycotic-resistant strains were sensitive to nanoparticles. This study indicates a high in vitro antifungal potential for the application of nanoparticles, especially AgCuNPs, as a new effective non-antibiotic agent for the prevention and control of mycotic mastitis in dairy cattle. Full article