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Silver nanoparticles (AgNPs) possess distinct physicochemical characteristics and demonstrate high antibacterial potential that highlights them as promising alternatives against a wide range of pathogens. The immense antibacterial potential of AgNPs is primarily attributed to the release of silver ions that lead to the disruption of bacterial cell membrane, generation of reactive oxygen species (ROS), inhibition of protein synthesis and interference with DNA replication. Variations in AgNPs’ shape, size, and surface characteristics are also considered key factors determining their effectivity as well as specificity. AgNPs are considered potent antibacterial agents, including against antibiotic- and drug-resistant strains. However, inappropriate dosages or unoptimized application of may result in potential toxicity, consisting one of the main drawbacks of the AgNPs’ safer administration. This article reviews the recent literature on the antibacterial potential of AgNPs, focusing on their broad mechanisms of action, applicability, especially in agriculture, biomedical and environmental fields, toxicity and future perspectives. Full article

Ascaris lumbricoides is one of the most epidemiologically significant soil-transmitted helminths, and the environmental persistence of its eggs is largely attributed to their robust structural architecture. The search for ovicidal alternatives capable of overcoming this barrier has increasingly focused on metallic nanoparticles obtained through biological synthesis. Scanning electron microscopy (SEM) was employed to evaluate the ultrastructural effects of silver nanoparticles (AgNPs) biosynthesised by the nematophagous fungus Duddingtonia flagrans on A. lumbricoides eggs. Ultraviolet-visible spectroscopy and transmission electron microscopy confirmed the synthesis of AgNPs, revealing predominantly spherical, well-dispersed particles with an average diameter of 9.22 ± 4.9 nm. Cytotoxicity assays indicated an IC₅₀ of 7.7 µg/mL. SEM analyses showed that eggs in the control group maintained intact morphology, with no apparent deformities. In contrast, exposure to AgNPs induced pronounced structural alterations, including marked wrinkling, surface erosion and shell collapse, suggesting disruption of multiple layers. Albendazole alone produced deep linear fissures consistent with internal metabolic failure, though with minimal external erosion. The combined treatment with AgNPs and albendazole resulted in severe degradation. These findings demonstrate that AgNPs exhibit significant ovicidal activity and may serve as effective adjuvants to enhance the action of conventional anthelmintics against highly resistant helminth eggs. Full article

Cutaneous leishmaniasis is a zoonotic disease caused by Leishmania parasites and leads to chronic, non-healing skin lesions. Although current drugs can control the disease, their use is limited by systemic side effects, low efficacy, and inadequate lesion penetration. Therefore, innovative local delivery systems are required to enhance drug penetration and reduce systemic toxicity. To address these challenges, silver nanoparticles (AgNPs) were synthesized using propolis extract through a green synthesis approach, and a tri-layer wound dressing composed of polyvinyl alcohol and gelatin containing synthesized AgNPs and Glucantime was fabricated by electrospinning. Characterization (SEM-EDX, FTIR, TGA) confirmed uniform morphology, chemical structure, and thermal stability; the wound dressing exhibited hydrophilicity, antioxidant activity, and biphasic release. Biological evaluations against Leishmania tropica demonstrated significant antiparasitic activity. Promastigote viability decreased from 76.3% in neat fibers to 31.6% in nanofibers containing AgNPs and 7.9% in tri-layer nanofibers containing both AgNPs and Glucantime. Similarly, the amastigote infection index dropped from 410 in controls to 250 in neat nanofibers, 204 in AgNPs-containing nanofibers, and 22 in tri-layer nanofibers containing AgNPs and Glucantime. The tri-layer nanofibers demonstrated enhanced antileishmanial activity over AgNPs-containing fibers, confirming synergistic efficacy. All nanofibers were biocompatible, supporting their use as a safe platform for cutaneous leishmaniasis treatment. Full article

Silver nanoparticles (AgNPs) are increasingly applied in agriculture and related technologies due to their antimicrobial properties, yet their interactions with soil-associated organisms and microbial communities remain insufficiently characterized. This study examined the effects of AgNP exposure (10.85 mg/L) on trace element accumulation and gut bacterial communities of the earthworm Eisenia fetida under two substrate conditions (horticultural substrate and compost). High-throughput 16S rRNA gene sequencing revealed substrate-dependent shifts in microbial community structure following AgNP exposure. Several bacterial taxa, including Proteobacteria, Gammaproteobacteria, Bacilli, Streptococcus sp., and Staphylococcus sp., exhibited pronounced numerical declines, indicating sensitivity to AgNPs, whereas Actinobacteria and Bacteroidetes showed comparatively higher relative abundances, suggesting greater tolerance. Compost partially mitigated the inhibitory effects of AgNPs on gut microbiota. Concurrently, AgNP exposure altered trace element accumulation patterns in earthworm tissues, highlighting interactions between silver uptake and elemental homeostasis. Collectively, these findings demonstrate that AgNPs can induce taxon- and substrate-specific responses in earthworm-associated microbial communities and metal accumulation, providing insight into potential ecological consequences of nanoparticle use in agricultural systems. Full article

Saccharomyces cerevisiae was cultured under the influence of static magnetic fields (SMFs) to assess their impact on the biosynthesis of silver nanoparticles (AgNPs). Cell-free media derived from SMF-exposed cultures facilitated the formation of AgNPs, with a significant reduction in nanoparticle size observed at an optimal field strength of 7 mT. AgNPs synthesized under SMF conditions exhibited smaller crystalline structures than those produced in control media, as evidenced by dynamic light scattering (DLS) and transmission electron microscopy (TEM) measurements. Over a 75-day period, SMF-exposed AgNPs demonstrated enhanced stability, as determined by DLS and polydispersity index (PDI) assessments. Further analysis through sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared spectroscopy (FTIR) suggested the formation of a protein corona on the AgNPs in SMF-treated samples, which likely inhibits agglomeration and enhances long-term stability. These findings indicate that SMF-induced stress in S. cerevisiae triggers the secretion of specific proteins that contribute to the stabilization of AgNPs, providing a novel approach to controlling nanoparticle synthesis and stability through magnetic field exposure. Full article

This study focuses on the development of antibacterial polymer nanocomposites based on biologically synthesized silver nanoparticles (AgNPs) and polyvinyl alcohol (PVA) as the polymer matrix. Silver nanoparticles were produced using an aqueous extract from dried Lavandula angustifolia (lavender) leaves, which proved to be highly effective in reducing silver ions and stabilizing the resulting nanoparticles. The synthesized AgNPs were characterized by FTIR, UV-Vis, TEM, SEM, and DLS analyses. The nanoparticles were predominantly spherical, with more than 70% having diameters below 20 nm. Subsequently, AgNPs were incorporated into the PVA matrix via an ex situ approach to fabricate nanocomposite fibers and thin films. SEM analysis confirmed successful incorporation and uniform distribution of AgNPs within the polymer structures. The nanocomposites exhibited pronounced antibacterial activity against both Gram-positive (Staphylococcus aureus, Staphylococcus haemolyticus, Streptococcus uberis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria, with nanofibers demonstrating superior performance compared to thin films. These findings highlight the potential of lavender-extract-mediated AgNPs as sustainable functional fillers for the fabrication of eco-friendly antibacterial materials applicable in biomedical and food packaging fields. Full article

Based on the pressing need to develop efficient desulfurization technologies for fuel oils, this study presents a novel photoresponsive adsorbent for the removal of refractory thiophenic sulfides. Conventional hydrodesulfurization exhibits limited efficiency for such compounds, while adsorption–desorption processes often suffer from high energy consumption during regeneration. Inspired by natural stimuli-responsive systems, we designed a photothermal adsorbent by incorporating silver nanoparticles (Ag NPs) into a porous aromatic framework (PAF) via a green photoreduction method. The resulting materials, denoted as Ag(0)PBPAF-n (n = 1, 2, 3), were thoroughly characterized to confirm successful synthesis and structural integrity. The introduced Ag NPs serve as adsorption sites, enhancing uptake capacity through weak interactions with sulfur atoms in thiophenic molecules. More significantly, under light irradiation, the localized surface plasmon resonance (LSPR) of Ag NPs enables efficient photothermal conversion, triggering rapid desorption without conventional heating. Adsorption–desorption tests demonstrated that up to 48% of adsorbed thiophenic sulfur could be released upon illumination. Fixed-bed experiments further verified that light can effectively stimulate regeneration and improve energy efficiency. This work offers a promising strategy for designing recyclable adsorbents with low-energy regeneration driven by clean solar energy. Full article

The study investigates the use of silver nanoparticles (AgNPs) in agriculture, focusing on their potential to enhance the immune response of potato (Solanum tuberosum L.) plants against phytopathogenic attacks. The research highlights how AgNPs, stabilized by biologically active polymers polyhexamethylene biguanide and tallow amphopolycarboxyglycinate, can induce oxidative stress. Triple foliar application of 0.1–9.0 g/ha silver nanoparticles at the budding and later stages demonstrated significant efficacy in suppressing diseases caused by Phytophthora infestans and Alternaria solani (over 60%). This effect was linked to the increased activity of peroxidase—over 30–50%—and the decreased catalase activity, indicative of a well-coordinated oxidative stress response to the invasion of P. infestans and A. solani. The results suggest that AgNPs in low concentrations can prime the plant’s innate immune system, enhancing its resistance without detrimental effects on growth parameters, thus contributing to the improved crop yield. These findings underscore the potential of AgNPs not as traditional biocides, but as intelligent elicitors of plant-induced resistance, positioning them as next-generation tools for sustainable crop protection and yield optimization, which can be applied at extremely low doses (less than 10 g/ha of active substance). Full article

Metal nanoparticles (NP) are increasingly used in biomedical applications. Among them, silver NPs (AgNPs) are used as active components in antibacterial coatings for wound dressings, medical devices, implants, cosmetics, textiles, and food packaging. On the other hand, AgNPs can be toxic to humans, depending on the dose and route of exposure, as agents delivering silver to cells. The cysteine residues are the primary molecular targets in such exposures, due to the high affinity of Ag⁺ ions to thiol groups. The Endothelial monocyte-activating polypeptide II (EMAP II), a cleaved C-terminal peptide of the intracellular aminoacyl-tRNA synthetase multifunctional protein AIMP1, contains five cysteines exposed at its surface. This prompted the question of whether they can be targeted by Ag⁺ ions present at the AgNPs surface or released from AgNPs in the course of oxidative metabolism of the cell. We explored the interactions between recombinant EMAP II, tRNA, and AgNPs using UV-Vis and fluorescence spectroscopy, providing insight into the effects of AgNPs dissolution kinetics on interaction EMAP II with tRNA. In addition, the EMAP II fragments binding to intact AgNPs were established by heteronuclear ¹H-¹⁵N HSQC spectra utilizing a paramagnetic probe. Structural analysis of the EMAP II reveal that the 3D structure of protein was destabilized (partially denatured) by the binding of Ag⁺ ions released from AgNPs at the most exposed cysteines. Surprisingly, this effect enhanced tRNA affinity to EMAP II, lowering its $K_d$. The course of the EMAP II/tRNA/AgNP reaction was also modulated by other factors, such as the presence of Mg²⁺ ions and TCEP, a thiol-group protector used to mimic the reducing conditions of the cell. Full article

Valsartan (Val)—a lipophilic non-peptide angiotensin II type 1 receptor antagonist—is highly effective against hypertension and displaying limited solubility in water (3.08 μg/mL), thereby resulting in low oral bioavailability (23%). The limited water solubility of antihypertensive drugs can pose a challenge, particularly for rapid and precise administration. Herein, we synthesize and characterize valsartan-containing silver nanoparticles (Val-AgNPs) using Mangifera indica leaf extracts. The physicochemical, structural, thermal, and pharmacological properties of these nano-conjugates were established through various analytical and structural tools. The spectral shifts in both UV-visible and FTIR analyses indicate a successful interaction between the valsartan molecule and the silver nanoparticles. The resulting nano-conjugates are spherical and within the size range of 30–60 nm as revealed in scanning electron-EDS and atomic force micrographs. The log-normal distribution of valsartan-loaded nanoparticles, with a size range of 30 to 60 nm and a mode of 54 nm, indicates a narrow, monodisperse, and highly uniform particle size distribution. This is a favorable characteristic for drug delivery systems, as it leads to enhanced bioavailability and a consistent performance. Dynamic Light Scattering (DLS) analysis of the Val-AgNPs indicates a polydisperse sample with a tendency toward aggregation, resulting in larger effective sizes in the suspension compared to individual nanoparticles. The accompanying decrease in zeta potential (to −19.5 mV) and conductivity further supports the idea that the surface chemistry and stability of the nanoparticles changed after conjugation. Differential scanning calorimetry (DSC) demonstrated the melting onset of the valsartan component at 113.99 °C. The size-dependent densification of the silver nanoparticles at 286.24 °C correspond to a size range of 40–60 nm, showing a significant melting point depression compared to bulk silver due to nanoscale effects. The shift in Rf for pure valsartan to Val-AgNPs suggests that the interaction with the AgNPs alters the compound’s overall polarity and/or its interaction with the stationary phase, complimented in HPTLC and HPLC analysis. The stability and offloading behavior of Val-AgNPs was observed at pH 6–10 and in 40% and 80% MeOH. In addition, Val-AgNPs did not reveal hemolysis or significant alterations in blood cell indices, confirming the safety of the nano-conjugates for biological application. In conclusion, these findings provide a comprehensive characterization of Val-AgNPs, highlighting their potential for improved drug delivery applications. Full article

This study aimed to develop an environmentally friendly composite film with effective antibacterial and preservation properties. Silver nanoparticles (AgNPs) were green-synthesized using grape skin extract as a natural reducing agent and incorporated into a PVA/chitosan matrix. The composition of the extract and the structural characteristics of the AgNPs were characterized by UPLC-MS and TEM. The barrier, mechanical performance, antibacterial, and fruit preservation properties of the resulting films were systematically evaluated. The results showed that the incorporation of AgNPs significantly improved the water vapor and oxygen barrier properties of the film and imparted excellent broad-spectrum antibacterial activity. In grape storage experiments, films with higher AgNPs content effectively delayed skin aging and moisture loss, maintaining better visual quality of the fruit. This work provides a green and feasible approach for the preparation of nanoparticle-enhanced antibacterial packaging materials based on natural products, with promising application potential. Full article

Agomelatine (AG) is a novel antidepressant characterized by distinct mechanism of action and minimal side effects. However, extensive first-pass hepatic metabolism limits its clinical efficacy after oral administration, leading to low bioavailability (<5%). To get around these restrictions, the current study set out to create and assess a rectal thermosensitive in situ gel using biosynthesized AG-silver nanoparticles (AG-AgNPs). AG-AgNPs were successfully synthesized with gum acacia as a stabilizing agent, using silver nitrate as a precursor, and ascorbic acid as a reducing agent. The in situ gel formulation was optimized using a 3² factorial design, and then physicochemical, in vitro, and in vivo assessments were conducted. Nanoparticle formation was also evidenced by the appearance of a visible color change, UV-VIS, TEM, and XRD analysis techniques, which depicted spherical-shaped nanoparticles and a crystalline nature. The formulated optimized thermosensitive in situ gel showed good properties, which included drug content of 91.64%, gelation temperature of 26.63 °C, pH of 7.2, gel strength of 36.98 s, and sustained drug release of 80.24% in 6 h. The relative bioavailability in animal studies showed a remarkable increase in systemic availability with 277.5% relative bioavailability in comparison to an oral tablet formulation. In summary, results show that the AG-AgNP-loaded thermosensitive in situ gel could have potential use as a rectal delivery drug for bypassing first-pass effects and improving bioavailability for the drug Agomelatine. Full article

The urgent need for silver-based antibacterial agents in clinical settings has driven the diversification of their delivery systems, evolving from traditional silver salt preparations to new silver nanoparticles (AgNPs) and silver-based composite functional materials. Research and application of various carrier systems have established a solid foundation for the clinical translation of silver. However, it is important to recognize that the clinical use of silver-based materials still faces several key challenges: one is the potential risk of cytotoxicity, another is the growing trend of bacterial resistance to silver, and the third is the heterogeneity of antibacterial properties in different wound microenvironments. Additionally, this study thoroughly examines the significant gap between basic research and clinical application of silver-based materials, highlighting that the lack of standardized clinical endpoint indicators and high-quality clinical research evidence are the main barriers to its standardized use. Future research should focus on four key areas: developing precise targeted delivery systems, creating combined treatments with silver and other antibacterial agents, enhancing biosafety through material engineering, and establishing a unified framework for clinical efficacy evaluation. Through systematic innovation and evidence-based clinical implementation, silver-based technologies hold broad potential and significant clinical value for addressing complex wound infections and alleviating the global antibiotic resistance crisis. Full article

Chronic and complex wounds require biomaterials that are both cytocompatible and antimicrobial. Herein, electrospun polycaprolactone (PCL) nanofiber membranes were coated with Type I collagen and functionalized with silver nanoparticles (AgNPs). The main objective was to assess fibroblast adhesion, proliferation, and cytotoxicity. Membrane morphology and surface characteristics were analyzed in a previous work by SEM, AFM, and wettability measurements, confirming the transformation from hydrophobic PCL to fully wettable collagen-coated surfaces. In this study, Murine 3T3 fibroblasts were cultured on PCL, PCL–Collagen, PCL–Collagen–Citrate, and PCL–Collagen–AgNPs membranes. Cellular activity was quantified using Alamar Blue assays at 24, 48, and 72 h, while cytotoxicity was determined by LDH release. Cellular viability and adhesion were studied using confocal microscopy. All membrane types supported fibroblast growth, with collagen-coated samples exhibiting the highest metabolic activity. AgNPs-functionalized membranes sustained overall cell viability above 90%, with cytotoxicity values of approximately 10% at 24 h and 20% at 48 h. Antimicrobial evaluations demonstrated complete inhibition of Pseudomonas aeruginosa and vancomycin-resistant Enterococcus, and partial inhibition of Staphylococcus aureus. These results indicate that collagen-coated, AgNPs-functionalized electrospun PCL membranes exhibit both high cytocompatibility and significant antimicrobial activity, supporting their potential as advanced wound-dressing materials. Full article

Substance-based medical devices (SBMDs) are increasingly used in wound care due to their favorable safety profile, physicochemical mechanisms of action, and therapeutic effectiveness. These products often incorporate biopolymers such as hyaluronic acid or chitosan, alone or in combination with antimicrobial agents like silver nanoparticles (AgNPs) or silver sulfadiazine (SSD), offering hydration, tissue protection, and control of microbial burden in both acute and chronic wounds. Despite their widespread clinical use, the regulatory classification of SBMDs under Regulation (EU) 2017/745 (MDR) remains one of the most challenging and debated areas within the current European framework. This review analyzes the scientific and regulatory context of topical SBMDs, with particular emphasis on borderline products that share similarities with medicinal products in terms of formulation, composition, or claimed effects. The discussion focuses on the application of MDR Annex VIII, specifically Rule 21 for substance-based devices and Rule 14 for devices incorporating medicinal substances with ancillary action, together with interpretative guidance provided by MDCG 2022-5 Rev.1 and the Association of the European Self-Care Industry (AESGP) Position Paper. Particular attention is given to the identification of the critical role of the primary mode of action (MoA) as the determining criterion for regulatory qualification, especially for products containing antimicrobial substances. Through selected examples and case analyses, the review highlights inconsistencies in classification across Member States and underscores the need for a more harmonized, evidence-based, and proportionate regulatory approach. Overall, SBMDs challenge traditional regulatory boundaries and call for a framework capable of accommodating complex, multifunctional products while ensuring patient safety and regulatory coherence. Full article