Silver nanoparticles: various methods of synthesis, size affecting factors and their potential applications–a review

Green synthesized Polyscias fulva silver nanoparticles ameliorate uterine fibroids in female Wistar Albino rats

Uterine fibroids affect a substantial proportion of women in their reproductive age. Despite their effectiveness, surgical options such as hysterectomy are invasive, costly, and associated with recurrences. Pharmacological treatments are non-curative, only alleviate symptoms, and associated with adverse effects. Polyscias fulva (Araliaceae) is traditionally used to manage uterine fibroids in East Africa. In this study we synthesized Polyscias fulva silver nanoparticles (PFAgNPs), evaluated their toxicity and activity against monosodium glutamate (MSG)-induced uterine fibroids in Wistar albino rats. The UV-visible spectroscopy showed maximal absorbance at 425 nm with adequate stability at varying temperatures, pH and storage conditions. Dynamic light scattering (DLS) analysis revealed an average hydrodynamic size of 107.4 d.nm, polydispersity index of 0.264, and zeta potential of -18.3 mV. X-ray diffraction (XRD) confirmed the crystalline nature of PFAgNPs with an average size of 25 nm while scanning electron microscopy (SEM) showed a spherical shape with an average size of 35 nm. The PFAgNPs caused lethargy, hyperventilation, and hyperactivity at a dose of 300 mg/kg BW, whereas 2000 mg/kg caused severe toxicity, resulting in death in acute toxicity testing. The no observed adverse effect level was 50 mg/kgBW, the lowest observed adverse effect level was 100 mg/kgBW, and median lethal dose (LD50) was 1000 mg/kg. The PFAgNPs significantly decreased (P < 0.05) serum proteins, cholesterol, estrogen and progesterone alongside preservation of the histoarchitecture of the uterus. Further research is needed to investigate the clinical safety of PFAgNPs in managing uterine fibroids.

Silver Nanoparticles as Antibacterials: Synthesis, Characterization, and Molecular Simulations Against β-Lactamase-Producing Enterobacter and Salmonella spp

Multidrug resistance poses a threat to public health all over the world. Evidences suggest that third-generation antibiotic resistance mediated by extended-spectrum beta-lactamases (ESBLs) in all Enterobacteriaceae species, especially in Enterobacter and Salmonella. In this study, silver nanoparticles (AgNPs) were synthesized and characterized using sol-gel synthesis and powder X-ray diffraction. It was shown that clinical isolates were sensitive to AgNPs. The MIC and MBC, time-dependent growth inhibition test as well as well diffusion agar techniques. ESBL generation was examined using these approaches. There was a low MIC value of 500 μg/ml for Enterobacter and Salmonella. 1000 μg/ml of AgNPs inhibited the development of microorganisms. The antibacterial effect of AgNPs was slow but dependent on concentration and duration. At a concentration of 100 μg/ml, the inhibition zone for Enterobacter was 22 mm, whereas that for Salmonella was 20 mm. Further, molecular docking employed to explore the binding affinity between AgNPs and the active site of beta-lactamase and compare it with reference. Results revealed a very strong score (- 26.79 kcal/mol). Next, MD simulation was performed. The MD simulation results showed a stable interaction between beta-lactamase-nanocluster. Experimental and computational results elucidate the molecular mechanism of anti-bacterial activity of AgNPs to fight against bacterial infections.

Silver Nanoparticles (AgNPs) as Potential Antiviral Agents: Synthesis, Biophysical Properties, Safety, Challenges and Future Directions─Update Review

AgNPs have gained significant attention due to their unique physicochemical properties, making them valuable across a range of fields including medicine, textiles, and household products. With their strong antimicrobial and antiviral properties, AgNPs have shown promise in treating infections, particularly in wound care management. This review explores the mechanisms underlying the antiviral activities of AgNPs, as well as the methods used for their synthesis, which include physical, chemical, and biological approaches. The review also addresses the potential limitations of AgNPs, including their cytotoxicity to humans and the environment. The interaction between AgNPs and microorganisms, particularly viruses, varies based on synthesis methods and particle morphology. As viral infections, including resistant strains, present major global health challenges, there is a growing need for alternative antiviral therapies. Metal nanoparticles like AgNPs offer potential advantages over conventional antiviral drugs due to their broad target range, which reduces the likelihood of resistance development. This review highlights AgNPs' effectiveness against a variety of viruses, such as HIV, hepatitis B, and respiratory syncytial virus, and discusses their potential for use in novel antiviral treatments. The review also examines AgNPs' toxicity, offering insights into their future therapeutic roles.

Green synthesis of silver nanoparticles using guava leaves: an effective strategy to control chilli fruit rot disease

BACKGROUND

Anthracnose, caused by Colletotrichum capsici, is a significant fungal disease affecting chilli crops, leading to yield losses of 10-25%. Traditional control methods, primarily chemical fungicides, not only pose risks to the environment and soil health but also threaten public safety. In contrast, nanotechnology presents a promising eco-friendly alternative, leveraging the unique properties of nanoparticles, such as their small size and high surface-to-volume ratio, to effectively manage fungal infections with minimal environmental impact.

RESULTS

This study investigates the synthesis, characterization, and antifungal activity of silver nanoparticles (Ag-NPs) synthesized from guava leaf extract against chilli fruit rot. UV-Vis spectroscopy confirmed the synthesis of Ag-NPs with a peak absorption at 431 nm. X-ray diffraction (XRD) analysis revealed a crystalline structure with an average particle size of 42.5 nm, while scanning electron microscopy (SEM) showed spherical nanoparticles with sizes ranging from 30.5 nm to 50.3 nm across different samples. Fourier transform infrared spectroscopy (FTIR) identified functional groups involved in silver ion reduction. Zeta size analysis confirmed particle sizes of 500.1 nm, 1.0 nm, 62.4 nm, 262.8 nm, and 178.8 nm for samples S1 through S5, respectively. In antifungal assays, S1 at 50 ppm exhibited the highest mycelial growth inhibition (47.9%), with significant protective (87%) and curative (93%) effects. Additionally, in in-vitro leaflet assays, S1 demonstrated 86% inhibition of C. capsici at 50 ppm, highlighting its potential as an effective agent for managing chilli fruit rot.

CONCLUSIONS

This study presents a rapid, eco-friendly method for synthesizing Ag-NPs using guava leaf extract, showing their potential in managing chilli fruit rot caused by C. capsici. The results highlight their effectiveness in both protective and curative applications, offering a sustainable alternative to chemical fungicides. Future research should focus on scaling up the synthesis process for industrial applications, exploring the long-term environmental impact, and assessing the broader applicability of Ag-NPs in managing other phytopathogenic diseases across various crops. Silver nanoparticles (Ag-NPs) synthesized from guava leaf extract effectively inhibit Colletotrichum capsici, with 86% antifungal activity at 50 ppm. This study highlights an eco-friendly, rapid synthesis method for Ag-NPs as a promising alternative to chemical fungicides in managing chilli fruit rot disease.

CLINICAL TRIAL NUMBER

Not applicable.

Salicylic Acid-Mediated Silver Nanoparticle Green Synthesis: Characterization, Enhanced Antimicrobial, and Antibiofilm Efficacy

Objectives: Silver nanoparticles (AgNPs) were synthesized via an easy and rapid biogenic synthesis approach, utilizing the dual capabilities of salicylic acid as both a reducing and capping agent. Methods: The characterization of Salicylic Acid-Mediated Silver Nanoparticle (SA-AgNPs) was conducted using a variety of techniques, including ultraviolet-visible spectroscopy, dynamic light scattering, scanning electron microscopy combined with energy dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, as well as thermogravimetric analysis paired with differential scanning calorimetry. Results: SA-AgNPs demonstrated significant antibacterial properties against both Gram-positive (methicillin-resistant Staphylococcus epidermidis, Staphylococcus aureus, Cutibacterium acnes, methicillin-resistant Staphylococcus aureus) and Gram-negative (Escherichia coli), with minimum inhibitory concentrations (MICs) of 8, 9, 8, 4, and 6 μg/mL, respectively. At a concentration of 32 μg/mL, SA-AgNPs exhibited 99.9% killing efficiency against Escherichia coli (E. coli), Cutibacterium acnes (C. acnes), and methicillin-resistant Staphylococcus aureus (MRSA), within 4, 16, and 12 h, respectively. At the same concentration, SA-AgNPs effectively inhibited 95.61% of MRSA biofilm formation. SA-AgNPs induced the leakage of intracellular macromolecular substances by increasing the membrane permeability, which ultimately caused bacterial apoptosis. Conclusions: Overall, this study presents a fast and environmentally friendly approach for synthesizing SA-AgNPs, with potential applications as nano antibiotics antibacterial coatings for implantable medical devices and wound dressings.

Design of engineered nanoparticles for biomedical applications by computational modeling

Engineered nanoparticles exhibit superior physicochemical, antibacterial, optical, and sensing properties compared to their bulk counterparts, rendering them attractive for biomedical applications. However, given that nanoparticle properties are sensitive to their nanostructural characteristics and their chemical stability is largely affected by physiological conditions, nanoparticle behavior can be unpredictable in vivo, requiring careful surface modification to ensure biocompatibility, prevent rapid aggregation, and maintain functionality under biological environments. Therefore, understanding the mechanisms of nanoparticle formation and macroscopic behavior in physiological media is essential for the development of structure-property relationships and, their rational design for biomedical applications. Computational simulations provide insight into nanoscale phenomena and nanoparticle dynamics, expediting material discovery and innovation. This review provides an overview of the process design and characterization of metallic and metal oxide nanoparticles with an emphasis on atomistic and mesoscale simulations for their application in bionanomedicine.

Metal Nanocomposites as Biosensors for Biological Fluids Analysis

Metal nanocomposites are rapidly emerging as a powerful platform for biosensing applications, particularly in the analysis of biological fluids. This review paper examines the recent advancements in the development and application of metal nanocomposites as biosensors for detecting various analytes in complex biological matrices such as blood, serum, urine, and saliva. We discuss the unique physicochemical properties of metal nanocomposites, including their high surface area, enhanced conductivity, and tunable optical and electrochemical characteristics, which contribute to their superior sensing capabilities. The review will cover various fabrication techniques, focusing on their impact on the sensitivity, selectivity, and stability of the resulting biosensors. Furthermore, we will analyze the diverse applications of these biosensors in the detection of disease biomarkers, environmental toxins, and therapeutic drugs within biological fluids. Finally, we will address the current challenges and future perspectives of this field, highlighting the potential for improved diagnostic tools and personalized medicine through the continued development of advanced metal nanocomposite-based biosensors.

Plasmon-Enhanced Photo-Luminescence Emission in Hybrid Metal-Perovskite Nanowires

Semiconductor photonic nanowires are critical components for nanoscale light manipulation in integrated photonic and electronic devices. Optimizing their optical performance requires enhanced photon conversion efficiency, for which a promising solution is to combine semiconductors with noble metals, using the surface plasmon resonance of noble metals to enhance the photon absorption efficiency. Here, we report plasmon-enhanced light emission in a hybrid nanowire device composed of perovskite semiconductor nanowires and silver nanoparticles formed using superfluid helium droplets. A cesium lead halide perovskite-based four-layer structure (CsPbBr3/PMMA/Ag/Si) effectively reduces the metal's plasmonic losses while ensuring efficient surface plasmon-photon coupling at moderate power. Microphotoluminescence and time-resolved spectroscopy techniques are used to investigate the optical properties and emission dynamics of carriers and excitons within the hybrid device. Our results demonstrate an intensity enhancement factor of 29 compared with pure semiconductor structures at 4 K, along with enhanced carrier recombination dynamics due to plasmonic interactions between silver nanoparticles and perovskite nanowires. This work advances existing approaches for exciting photonic nanowires at low photon densities, with potential applications in optimizing single-photon excitations and emissions for quantum information processing.

Role of Endophytic Fungi in the Biosynthesis of Metal Nanoparticles and Their Potential as Nanomedicines

Metal nanoparticles (MNPs) produced through biosynthesis approaches have shown favourable physical, chemical, and antimicrobial characteristics. The significance of biological agents in the synthesis of MNPs has been acknowledged as a promising alternative to conventional approaches such as physical and chemical methods, which are confronted with certain challenges. To meet these challenges, the use of endophytic fungi as nano-factories for the synthesis of MNPs has become increasingly popular worldwide in recent times. This review provides an overview of the synthesis of MNPs using endophytic fungi, the mechanisms involved, and their important biomedical applications. A special focus on different biomedical applications of MNPs mediated endophytic fungi involved their antibacterial, antifungal, antiviral, and anticancer applications and their potential as drug delivery agents. Furthermore, this review highlights the significance of the use of endophytic fungi for the green synthesis of MNPs and discusses the benefits, challenges, and prospects in this field.

A comprehensive review on the green synthesis of silver nanoparticles from marine sources

The primary purpose of this review is to explore the green synthesis of silver nanoparticle (AgNP) using natural biomolecules derived from marine sources. This review aims to evaluate the effectiveness of environmentally friendly approaches for synthesizing AgNPs and to examine their potential applications across various fields such as medicine, biotechnology, and environmental remediation. The key research question focuses on understanding how marine biomolecules, including polysaccharides, proteins, enzymes, amino acids, alkaloids, and vitamins, contribute to the formation of AgNPs and how these green-synthesized nanoparticles retain their functional properties. This review systematically examines current literature on the green synthesis of AgNPs, focusing on marine-derived biomolecules such as polysaccharides, proteins, and alkaloids. The methodology includes analyzing green synthesis techniques and comparing them with traditional chemical methods to highlight environmental benefits and overall efficiency. Various marine species, such as seagrass and seaweed, are explored as potent agents in the reduction of silver ions. The findings reveal that green synthesis of AgNPs using marine biomolecules is not only environmentally sustainable but also retains the desirable properties of the nanoparticles, such as antimicrobial, antioxidant, and anticancer activities. Additionally, the green-synthesized AgNPs show significant potential applications in mosquito control, wound healing, and anticancer therapies. Green synthesis of AgNPs using marine sources presents a viable and sustainable alternative to conventional chemical methods, significantly reducing the environmental impact of nanoparticle production while ensuring biocompatibility and functional integrity. This approach holds promise for diverse applications in biomedicine, environmental remediation, and beyond. Further research is recommended to address challenges in scaling up production and commercialization.

Green synthesis of silver and zinc oxide nanoparticles with Thespesia populnea extract and investigation of their antioxidant potential against mouse mastitis model

Introduction

Bovine mastitis in dairy cattle is often complicated by antibiotic-resistant bacteria such as Staphylococcus aureus. Metal-based nanoparticles, especially plant-mediated nanoparticles have emerged as promising therapeutic tools for treating S. aureus-associated mastitis through the intramammary route. In this study, we synthesized, characterized, and assessed the antioxidant activity of Thespesia populnea nano silver particles (TPNS) and Thespesia populnea nano zinc oxide particles (TPNZ) derived from Thespesia populnea leaf extract (TPE). Silver nitrate and zinc acetate were reduced using TPE to synthesize TPNS and TPNZ, which were characterized by Scanning Electron Microscopy (SEM), UV-Visible Spectroscopy, Dynamic Light Scattering (DLS), and Zeta Potential analysis. The antioxidant activity of green-synthesized nanoparticles was evaluated in mastitis-induced mice.

Methods

Forty-eight female Swiss albino mice, 10-15 days of lactation, were divided into six groups (number of mice in each group-8). Group I served as the control, while mastitis was induced in groups II, III, IV, V and VI. Group III received T. populnea methanolic leaf extract (TPE); groups IV and V were treated with TPNS and TPNZ respectively; and group VI received Ceftriaxone.

Results

UV-Visible Spectroscopy confirmed the successful reduction of the metal ions to nanoparticles. SEM and DLS analysis revealed agglomerated morphologies with minimal variations in particle size. TPNS had a higher zeta potential than TPNZ, indicating a greater stability in the suspension. Mastitis-induced group showed significantly increased thiobarbituric acid reacting substances (TBARS) levels (p < 0.01) and significantly decreased Superoxide dismutase (SOD), Glutathione- S- transferase (GST), catalase (CAT), reduced glutathione (GSH), and glutathione peroxidase (GPx) activities (p < 0.01) compared to group I. Improvements were observed in groups IV, VI, V, and III.

Conclusion

The TPNS-treated group (IV) showed the highest restoration of antioxidant activity, followed by the ceftriaxone (VI), TPNZ (V), and TPE-treated groups (III). These findings suggest that phytogenic nanoparticles exhibit higher antioxidant activity than TPE extract alone.

Sensitive and selective silver nanoparticle-based fluorescence sensor for corticosteroid determination in pharmaceutical formulations

Glucocorticoids play a crucial role in metabolic processes and have potent anti-inflammatory and immunosuppressive properties. Hence, developing a facile, sensitive, selective, and green approach to determine corticosteroids is essential. In this study, silver nanoparticles (Ag-NPs) were synthesized via the chemical reduction of silver nitrate using sodium borohydride in distilled water without using non-environmentally friendly organic stabilizers. The synthesized Ag-NPs exhibited high stability, as evidenced by a zeta potential measuring - 36.8 mV. Also, the average particle size was determined to be 8 ± 2 nm. These Ag-NPs were then employed as a nano fluorescence probe to establish a fluorometric assay for determining prednisolone sodium phosphate (PDN) and dexamethasone sodium phosphate (DXZ). Reduction in fluorescence intensity of Ag-NPs observed at 484 nm following excitation at 242 nm exhibited quantitative quenching upon the incremental addition of the investigated drugs, with limits of detection of 0.178 µg/mL and 0.145 µg/mL for PDN and DXZ, respectively. The quenching mechanisms were examined and explained using the Stern-Volmer and Inner Filter Effect methods. The method's selectivity was also assessed by testing other corticosteroids. The proposed method is suitable for drug testing in pharmaceutical products and quality control labs. It follows ICH guidelines and has been confirmed to be safe and eco-friendly.

A color-coordinated approach to the flow synthesis of silver nanoparticles with custom morphologies

In an effort to meet the high demand for silver nanostructures in both research and consumer applications, we devise a simple and readily scaleable photochemical method through which silver nanostructures of varying morphologies, sizes, and optical properties can be synthesized using batch and flow photochemical strategies. For the latter we build upon the application of a wrapped-lamp photochemical flow system recently developed by our group to enable sequential irradiation with several wavelengths of LEDs in series in an approach that we describe as "plasmon pushing". We find that this strategy can accelerate the conversion of silver nanoparticle seeds to decahedral and triangular nanostructures, and that with it we have control over the tuning of the size and optical properties of triangular nanostructures in the red and near-IR regions. Moreover, through sequential flow irradiation, we gain a better understanding of the formation pathways and relative stability of decahedral and triangular silver nanostructures.

Silver nanoparticle (AgNP), neurotoxicity, and putative adverse outcome pathway (AOP): A review

Various silver nanoparticles (AgNPs) exist with different sizes, coatings, and shapes. AgNPs have unique physical and chemical properties, such as high surface-to-volume ratio and antimicrobial properties, which allow them to be used in a wide array of applications in consumer products and medical applications, including clothing, cosmetics, food packaging, medical devices, and wound dressings. They are also one of the most studied engineered nanomaterials (ENMs). Though the liver and lung have been identified as the primary targets of AgNP exposures, an increasing number of studies have reported accumulations of AgNPs in the brains of AgNP-exposed animals. These findings have raised concerns because the brain plays a critical function in our body and may have difficulty clearing AgNPs, unlike the liver and lung. Studies have been conducted to investigate potential neurotoxicity effects of AgNP exposures, but they use various types of AgNPs and routes of administration, which makes it difficult to compare across studies. Therefore, the goal of this review was to (1) assess factors that may affect AgNP-induced neurotoxicity, (2) identify potential mechanisms of neurotoxicity exerted by AgNPs, (3) review existing in vitro dose-response and in vivo exposure-response AgNP-induced neurotoxicity studies, and (4) provide an example application of benchmark doses (BMDs) in comparing across different studies. A combination of aggregate exposure pathway (AEP) and adverse outcome pathway (AOP) framework was utilized to link AgNP exposure sources and routes to molecular initiating events (MIEs) and then to adverse neurotoxicity outcomes at the cellular, organ, organism, and population levels. This review is the first to propose an AEP/AOP specific to AgNP-induced neurotoxicity, which may contribute toward identifying plausible key event relationships between MIEs and adverse neurotoxicity outcomes and improving the current risk assessment of AgNPs.

Advancements in Green Synthesis of Silver-Based Nanoparticles: Antimicrobial and Antifungal Properties in Various Films

Nanotechnology is an evolving field that presents extensive opportunities in antimicrobial and eco-friendly food packaging applications. Silver nanoparticles (AgNPs) are particularly valuable in this context due to their outstanding physicochemical properties and demonstrated biological and antimicrobial efficacy, rendering them highly effective in food packaging applications. Historically, nanoparticle synthesis has largely relied on synthetic chemicals and physical methods; however, growing awareness of their potential toxic impacts on human health and the environment has led researchers to reassess these conventional approaches. In response, green synthesis using plants or their metabolites to produce nanoparticles (NPs) has emerged as a focal point in recent research. This approach provides significant advantages, notably in reducing toxicity associated with traditionally synthesized nanoparticles. Silver, recognized for its non-toxic, safe profile as an inorganic antibacterial and antifungal agent, has been employed for centuries and exhibits remarkable potential in various biological applications in its nanoparticle form. Environmentally friendly synthesis techniques are increasingly prioritized within chemical sciences to reduce the harmful byproducts of reactions. Green synthesis methods also offer economic benefits due to their lower costs and the abundant availability of natural raw materials. In the past five years, concerted efforts have been made to develop new, sustainable, and cost-effective methodologies for nanoparticle synthesis. This review explains the green synthesis of silver nanoparticles from different sources along with their quantification techniques and application in food packaging.

Silver Nanoparticles Help Plants Grow, Alleviate Stresses, and Fight Against Pathogens

The use of silver nanoparticles (AgNPs) has gained importance in agriculture in recent years thanks to their unique characteristics, including their antimicrobial capacity and their ability to promote plant growth. Due to these attributes, AgNPs are considered a promising solution for the future of agriculture, offering significant potential to address the challenges the sector confronts currently. However, it is important to adjust the application conditions, depending on the target and the crop used, to improve AgNP treatment efficiency. This review compiles recent advances in the use of AgNPs for crop production, both in and ex vitro. AgNPs promote growth and alleviate biotic and abiotic stresses through different ex vitro application methods. They are also efficiently used in vitro to improve plant culture and pathogen elimination. In addition, the safety and toxicity associated with their use are discussed. AgNPs are a novel tool with great potential for the agricultural sector, but it is still necessary to continue researching the mechanisms of AgNP action in order to optimize their application in each specific case.

Green Synthesis of Nanoparticles in Mitigating Postharvest Losses of Fruits and Vegetables

The green synthesis of silver nanoparticles (AgNPs) from biological waste is an emerging technology that has excellent antibacterial properties. The present study has been designed to prepare silver nanoparticles by adopting green synthesis, which is based on the drying of fruits and vegetable peel to form silver nanoparticles. Two types of fruits (apples and tomatoes) and three types of vegetables (carrots, capsicum, and cucumber) were divided into three groups: one group was kept without any treatment, the second group was subjected to nanoparticles without silver nitrate, and the third group was subjected to silver nanoparticles. All the groups were stored for 15 days at room temperature and assessed for the physiochemical analysis of fruits and vegetables at 0 and 15th day and weight loss at 0, 5, 10, and 15th day of storage. Specifically, the titratable acidity of apples increased from 1.45 to 1.47 g/L, whereas nanoparticles and silver nanoparticles-treated apples ranged from 1.40 to 1.43 g/L. For tomatoes, the titratable acidity decreased from 0.54 to 0.44 g/L in controls, compared to 0.39-0.44 g/L in treated samples. Carrots in the control group decreased from 0.38 to 0.32 g/L, whereas treated samples maintained 0.29-0.34 g/L. Capsicum's acidity fell from 0.37 to 0.27 g/L in controls, compared to 0.28-0.32 g/L in treated capsicum. Cucumber's acidity decreased from 0.23 to 0.17 g/L in controls, whereas treated cucumbers showed 0.40-0.46 g/L. Overall, the nanoparticle treatments were effective in preserving the produce's titratable acidity, indicating enhanced freshness and extended shelf life. It was examined that treatments treated with nanoparticles and silver nanoparticles have a great impact on the shelf life of fruits and vegetables. There is a great possibility of using nanoparticles and silver nanoparticles in combination with peel extract of fruits and vegetables to improve the shelf life of vegetables and fruits.

Green-synthesised silver and zinc oxide nanoparticles from stingless bee honey: Morphological characterisation, antimicrobial action, and cytotoxic assessment

This study investigated the green synthesis of silver nanoparticles (Ag-NPs) and zinc oxide nanoparticles (ZnO-NPs) using an aqueous extract of stingless bee honey (SBH) as a reducing and stabilising agent. The rich compositions of SBH containing flavonoids, phenolics, organic acids, sugars, and enzymes makes the SBH extract an ideal biocompatible precursor for the NPs synthesis. Physicochemical characterisation of the synthesised NPs was performed using UV-Vis spectroscopy, FESEM, TEM, XRD, and FTIR spectroscopy. The results revealed that the Ag-NPs and ZnO-NPs exhibited polydispersity, with size ranges between 25-50 nm and 15-30 nm, respectively. A majority of the NPs possessed a spherical morphology. Furthermore, the study evaluated the antimicrobial activity of the SBH-based NPs against gram-positive (Staphylococcus aureus, ATCC 43300) and gram-negative (Escherichia coli, ATCC 25922) bacteria. The findings demonstrated significantly higher antimicrobial efficacy of the Ag-NPs with a zone of inhibition (ZOI) of 16.91 mm against S. aureus, and 17.43 mm against E. coli compared to the ZnO-NPs which having a ZOI of 13.05 mm and 14.01 mm, respectively. Notably, cytotoxicity assays revealed no adverse effects of the synthesised NPs on normal mouse fibroblast (3T3) and human lung fibroblast (MRC5) cells up to 100 μg/ml of concentration. These findings suggest the potential of SBH-based Ag-NPs and ZnO-NPs as safe and effective antibacterial agents for various applications, including pharmaceuticals, cosmetics, ointments, and lotions.

A review on green synthesis of silver nanoparticles (SNPs) using plant extracts: a multifaceted approach in photocatalysis, environmental remediation, and biomedicine

A sustainable and viable alternative for conventional chemical and physical approaches is the green production of silver nanoparticles (SNPs) using plant extracts. This review centers on the diverse applications of plant-mediated SNPs in biomedicine, environmental remediation, and photocatalysis. Ocimum sanctum (tulsi), Curcuma longa (turmeric), and Azadirachta indica (neem) and many others are plant extracts that have been used as stabilizing and reducing agents because of their extensive phytochemical profiles. The resulting SNPs have outstanding qualities, such as better photocatalytic degradation of organic dyes like methylene blue, antibacterial efficacy towards multidrug-resistant pathogens, biocompatibility for possible therapeutic applications, and regulated magnitude (10-50 nm), enhanced rigidity, and tunable surface plasmon resonance. Significant effects of plant extract type, amount, and synthesis parameters on the physical and functional characteristics of SNPs are revealed by key findings. Along with highlighting important issues and potential paths forward, this review also underlines the necessity of scalable production, thorough toxicity evaluations, and investigating the incorporation of SNPs into commercial applications. This work highlights how plant-based SNPs can be used to address global environmental and biological concerns by straddling the division between sustainable chemistry and nanotechnology.

Silver CVD and ALD Precursors: Synthesis, Properties, and Application in Deposition Processes

This review summarized the developments in the field of volatile silver complexes, which can serve as precursors in gas-transport reactions for the production of thin films and metal nanoparticles via chemical vapor deposition (CVD) and atomic layer deposition (ALD). Silver-based films and nanoparticles are widely used in various high-tech fields, including medicine. For effective use in CVD and ALD processes, the properties of silver precursors must be balanced in terms of volatility, thermal stability, and reactivity. In this review, we focus on the synthesis and comprehensive analysis of structural and thermal characteristics for the most promising classes of volatile silver complexes, as well as organometallic compounds. Following the specifics of silver chemistry, some features of the use of precursors and their selection, as well as several key directions to improving the efficiency of silver material deposition processes, are also discussed.

Role of Silver Nanoparticles for the Control of Anthelmintic Resistance in Small and Large Ruminants

Helminths are considered a significant threat to the livestock industry, as they cause substantial economic losses in small and large ruminant farming. Their morbidity and mortality rates are also increasing day by day as they have zoonotic importance. Anthelmintic drugs have been used for controlling these parasites; unfortunately, due to the development of resistance of these drugs in helminths (parasites), especially in three major classes like benzimidazoles, nicotinic agonists, and macrocyclic lactones, their use is becoming very low. Although new anthelmintics are being developed, the process is time-consuming and costly. As a result, nanoparticles are being explored as an alternative to anthelmintics. Nanoparticles enhance drug effectiveness, drug delivery, and target specificity and have no resistance against parasites. Different types of nanoparticles are used, such as organic (chitosan) and inorganic (gold, silver, zinc oxide, iron oxide, and nickel oxide). One of them, silver nanoparticles (AgNPs), has unique properties in various fields, especially parasitology. AgNPs are synthesized from three primary methods: physical, chemical, and biological. Their primary mechanism of action is causing stress through the production of ROS that destroys cells, organs, proteins, and DNA parasites. The present review is about AgNPs, their mode of action, and their role in controlling anthelmintic resistance against small and large ruminants.

Design rules applied to silver nanoparticles synthesis: A practical example of machine learning application

The synthesis of silver nanoparticles with controlled physicochemical properties is essential for governing their intended functionalities and safety profiles. However, synthesis process involves multiple parameters that could influence the resulting properties. This challenge could be addressed with the development of predictive models that forecast endpoints based on key synthesis parameters. In this study, we manually extracted synthesis-related data from the literature and leveraged various machine learning algorithms. Data extraction included parameters such as reactant concentrations, experimental conditions, as well as physicochemical properties. The antibacterial efficiencies and toxicological profiles of the synthesized nanoparticles were also extracted. In a second step, based on data completeness, we employed regression algorithms to establish relationships between synthesis parameters and desired endpoints and to build predictive models. The models for core size and antibacterial efficiency were trained and validated using a cross-validation approach. Finally, the features' impact was evaluated via Shapley values to provide insights into the contribution of features to the predictions. Factors such as synthesis duration, scale of synthesis and the choice of capping agents emerged as the most significant predictors. This study demonstrated the potential of machine learning to aid in the rational design of synthesis process and paves the way for the safe-by-design principles development by providing insights into the optimization of the synthesis process to achieve the desired properties. Finally, this study provides a valuable dataset compiled from literature sources with significant time and effort from multiple researchers. Access to such datasets notably aids computational advances in the field of nanotechnology.

Silver nanoparticles enhance the mitigation of osmotic stress in Chenopodium quinoa microshoots grown under in vitro osmo-stressing conditions

Osmotic stress is one of the main destructive abiotic factors that hinder plant growth and development. In this research, the role of silver nanoparticles (Ag NPs) in mitigating the negative impact of osmotic stress on in vitro grown Chenopodium quinoa (Quinoa 6 Line; Q6) was investigated to determine whether Ag NPs were able to reduce the negative effects on the in vitro grown cultures of the Q6 line. The explants were subcultured onto a special osmostressing media containing sucrose, sorbitol, or mannitol at different levels (0.1, 0.2, 0.3, and 0.4 mol/L) to mimic the osmotic stressing environment for four weeks. Then, stress physiological responses of in vitro grown Q6 under the induced osmotic stress were investigated to determine the highest stress level that the microshoots could tolerate. Next, Ag NPs; 25, 50, and 75 mg/L were added to the medium that contained the highest stress level of the induced osmotic stress to determine if their addition improved the physiological performance of the Q6 microshoots under the most severe osmotic agent levels. The results revealed that 0.4 mol/L sucrose, 0.3 mol/L sorbitol, and 0.3 mol/L mannitol were the highest stress levels that the microshoots could tolerate. The addition of 75 mg/L Ag NPs to the previous highest stress levels resulted in a significant increase in the following: stem length (SL), leaves number (LN), fresh weight (FW), dry weight (DW), total chlorophyll, protein, calcium (Ca), and phosphorus (P) contents, while it caused a reduction in proline, sodium (Na) ions, and potassium (K) ions. These results indicate that the negative consequences of osmotic stress on Q6 quinoa microshoots could be mitigated by adding specific concentrations of Ag NPs to the culture medium.

Using Femtosecond Laser Light to Investigate the Concentration- and Size-Dependent Nonlinear Optical Properties of Laser-Ablated CuO Quantum Dots

In this work, the nonlinear optical (NLO) properties of CuO nanoparticles (CuO NPs) were studied experimentally using the pulsed laser ablation (PLA) technique. A nanosecond Nd: YAG laser was employed as the ablation excitation source to create CuO NPs in distilled water. Various CuO NPs samples were prepared at ablation periods of 20, 30, and 40 min. Utilizing HR-TEM, the structure of the synthesized CuO NPs samples was verified. In addition, a UV-VIS spectrophotometer was used to investigate the linear features of the samples. The Z-scan technique was utilized to explore the NLO properties of CuO NPs samples, including the nonlinear absorption coefficient (β) and nonlinear refractive index (n2). An experimental study on the NLO features was conducted at a variety of excitation wavelengths (750-850 nm), average excitation powers (0.8-1.2 W), and CuO NPs sample concentrations and sizes. The reverse saturable absorption (RSA) behavior of all CuO NPs samples differed with the excitation wavelength and average excitation power. In addition, the CuO NPs samples demonstrated excellent optical limiters at various excitation wavelengths, with limitations dependent on the size and concentration of CuO NPs.

Nanotechnology in action: silver nanoparticles for improved eco-friendly remediation

Nanotechnology is an exciting area with great potential for use in biotechnology due to the far-reaching effects of nanoscale materials and their size-dependent characteristics. Silver and other metal nanoparticles have attracted a lot of attention lately because of the exceptional optical, electrical, and antimicrobial characteristics they possess. Silver nanoparticles (AgNPs) stand out due to their cost-effectiveness and abundant presence in the earth's crust, making them a compelling subject for further exploration. The vital efficacy of silver nanoparticles in addressing environmental concerns is emphasized in this thorough overview that dives into their significance in environmental remediation. Leveraging the distinctive properties of AgNPs, such as their antibacterial and catalytic characteristics, innovative solutions for efficient treatment of pollutants are being developed. The review critically examines the transformative potential of silver nanoparticles, exploring their various applications and promising achievements in enhancing environmental remediation techniques. As environmental defenders, this study advocates for intensified investigation and application of silver nanoparticles. Furthermore, this review aims to assist future investigators in developing more cost-effective and efficient innovations involving AgNPs carrying nanoprobes. These nanoprobes have the potential to detect numerous groups of contaminants simultaneously, with a low limit of detection (LOD) and reliable reproducibility. The goal is to utilize these innovations for environmental remediation purposes.

Quercetin-Derived Platinum Nanomaterials Influence Particle Stability, Catalytic, and Antimicrobial Performance

Quercetin possesses high biological properties but low bioavailability, poor solubility, and rapid body clearance. Its structural modification is imperative for enhanced applications. Herein, we demonstrate the catalytic and antimicrobial characteristics of shape-dependent (cuboidal and peanuts) platinum nanoparticles. Modified quercetin, 4'-QP, was employed as the reducing and stabilizing agent for the aqueous synthesis of PtNPs without extraneous reagents. Monodispersed platinum nanocubes (C-PtNPs) and nanopeanuts (P-PtNPs) were produced by reacting 4'-QP and Pt ions in the ratios of 3:1 and 1:1, respectively. TEM characterization confirmed the formation of Pt nanocubes and Pt nanopeanuts, with their corresponding sizes of 39.1 ± 0.20 and 45.1 ± 0.24 nm. The shape-dependency of PtNPs on the nosocomial-causing bacteria, Citrobacter freundii ATCC 8090 (C. freundii) was determined by the Agar well-diffusion assay. Under the same particle size and dose treatments, C-PtNPs and P-PtNPs exhibited 16.28 ± 0.10 and 4.50 ± 0.15 mm zones of inhibition with minimum inhibitory concentrations of 25 and 45 μg/mL, respectively. SEM analysis of C-PtNPs treated C. freundii showed a damaged cell membrane and confirmed contact-killing as the antibacterial mechanism. The catalytic conversion of 4-nitrophenol (4-NP) to 4-amino phenol (4-AP) was tested using a shape-dependent PtNPs catalyst in the presence of sodium borohydride. The conversion rates (k) of C-PtNPs and P-PtNPs in wastewater samples from New Jersey were 0.0108 and 0.00607 s-1, respectively.

Application of nanoparticles in breast cancer treatment: a systematic review

It is estimated that cancer is the second leading cause of death worldwide. The primary or secondary cause of cancer-related mortality for women is breast cancer. The main treatment method for different types of cancer is chemotherapy with drugs. Because of less water solubility of chemotherapy drugs or their inability to pass through membranes, their body absorbs them inadequately, which lowers the treatment's effectiveness. Drug specificity and pharmacokinetics can be changed by nanotechnology using nanoparticles. Instead, targeted drug delivery allows medications to be delivered to the targeted sites. In this review, we focused on nanoparticles as carriers in targeted drug delivery, their characteristics, structure, and the previous studies related to breast cancer. It was shown that nanoparticles could reduce the negative effects of chemotherapy drugs while increasing their effectiveness. Lipid-based nanocarriers demonstrated notable results in this instance, and some products that are undergoing various stages of clinical trials are among the examples. Nanoparticles based on metal or polymers demonstrated a comparable level of efficacy. With the number of cancer cases rising globally, many researchers are now looking into novel treatment approaches, particularly the use of nanotechnology and nanoparticles in the treatment of cancer. In order to help clinicians, this article aimed to gather more information about various areas of nanoparticle application in breast cancer therapy, such as modifying their synthesis and physicochemical characterization. It also sought to gain a deeper understanding of the mechanisms underlying the interactions between nanoparticles and biologically normal or infected tissues.

Inflammatory response of nanoparticles: Mechanisms, consequences, and strategies for mitigation

Numerous nano-dimensioned materials have been generated as a result of several advancements in nanoscale science such as metallic nanoparticles (mNPs) which have aided in the advancement of related research. As a result, several significant nanoscale materials are being produced commercially. It is expected that in the future, products that are nanoscale, like mNPs, will be useful in daily life. Despite certain benefits, widespread use of metallic nanoparticles and nanotechnology has negative effects and puts human health at risk because of their continual accumulation in closed biological systems, along with their complex and diverse migratory and transformation pathways. Once within the human body, nanoparticles (NPs) disrupt the body's natural biological processes and trigger inflammatory responses. These NPs can also affect the immune system by activating separate pathways that either function independently or interact with one another. Cytotoxic effects, inflammatory response, genetic material damage, and mitochondrial dysfunction are among the consequences of mNPs. Oxidative stress and reactive oxygen species (ROS) generation caused by mNPs depend upon a multitude of factors that allow NPs to get inside cells and interact with biological macromolecules and cell organelles. This review focuses on how mNPs cause inflammation and oxidative stress, as well as disrupt cellular signaling pathways that support these effects. In addition, possibilities and problems to be reduced are addressed to improve future research on the creation of safer and more environmentally friendly metal-based nanoparticles for commercial acceptance and sustainable use in medicine and drug delivery.

Potential use of silver nanoparticles green synthesized using Astragalus spinosus extract for treating cystic echinococcosis

The present investigation aims to develop and evaluate silver nanoparticles (AgNP) synthesized through environmentally friendly methods and to assess their effectiveness against hydatid cysts through in vitro, ex vivo, and in vivo experiments. The green synthesis of ANP was accomplished using the precipitation technique with Astragalus spinosus extract. The in vitro protoscolicidal effects of ANP were evaluated on hydatid cyst protoscoleces (PTS) through eosin exclusion test. The study also investigated the effect of ANP on the gene expression levels of caspase-3 and 9, as well as the external morphology of PTS. The in vivo efficacy was assessed by analyzing the quantity, dimensions, and weight of hydatid cysts in infected mice. Real-time PCR was used to analyze the gene expression levels of antioxidant and inflammatory cytokines. ANP exhibited significant (p < 0.001) in vitro protoscolicidal activity in a dose- and time-dependent manner. Treatment with ANP resulted in creases and protrusions on the plasma membrane, indicating bleb formation and an increase in the expression of caspase-3 and caspase-9 genes. Notably, there was a significant (p < 0.001) reduction in the number, size, and weight of hydatid cysts following ANP treatment. Administration of ANP resulted in a significant increase in the expression of antioxidant genes (glutathione peroxidase and superoxide dismutase) and a notable decrease in oxidative stress markers, as well as in the expression levels of Interleukin-4 (IL-4) and IL-10. Due to its antioxidant and anti-inflammatory properties, ANP shows potential as a scolicidal agent and holds promise in managing hydatid cysts in a mouse model. Nevertheless, further clinical trials are imperative to validate the efficacy of ANP in treating hydatidosis.

Silver Nanoparticles: Synthesis, Structure, Properties and Applications

Silver nanoparticles (Ag NPs) have accumulated significant interest due to their exceptional physicochemical properties and remarkable applications in biomedicine, electronics, and catalysis sensing. This comprehensive review provides an in-depth study of synthetic approaches such as biological synthesis, chemical synthesis, and physical synthesis with a detailed overview of their sub-methodologies, highlighting advantages and disadvantages. Additionally, structural properties affected by synthesis methods are discussed in detail by examining the dimensions and surface morphology. The review explores the distinctive properties of Ag NPs, including optical, electrical, catalytic, and antimicrobial properties, which render them beneficial for a range of applications. Furthermore, this review describes the diverse applications in several fields, such as medicine, environmental science, electronics, and optoelectronics. However, with numerous applications, several kinds of issues still exist. Future attempts need to address difficulties regarding synthetic techniques, environmental friendliness, and affordability. In order to ensure the secure utilization of Ag NPs, it is necessary to establish sustainability in synthetic techniques and eco-friendly production methods. This review aims to give a comprehensive overview of the synthesis, structural analysis, properties, and multifaceted applications of Ag NPs.

Re-designing nano-silver technology exploiting one-pot hydroxyethyl cellulose-driven green synthesis

Re-designing existing nano-silver technologies to optimize efficacy and sustainability has a tangible impact on preventing infections and limiting the spread of pathogenic microorganisms. Advancements in manufacturing processes could lead to more cost-effective and scalable production methods, making nano-silver-based antimicrobial products more accessible in various applications, such as medical devices, textiles, and water purification systems. In this paper, we present a new, versatile, and eco-friendly one-pot process for preparing silver nanoparticles (AgNPs) at room temperature by using a quaternary ammonium salt of hydroxyethyl cellulose (HEC), a green ingredient, acting as a capping and reducing agent. The resulting nano-hybrid phase, AgHEC, consists of AgNPs embedded into a hydrogel matrix with a tunable viscosity depending on the conversion grade, from ions to nanoparticles, and on the pH. To investigate the synthesis kinetics, we monitored the reaction progress within the first 24 h by analyzing the obtained NPs in terms of particle size (dynamic light scattering (DLS), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM)), Z-potential (ELS), surface plasmon resonance (UV-VIS), crystallographic phase (XRD), viscosity, and reaction yield (inductively coupled plasma-optical emission spectrometry (ICP-OES)). To explore the design space associated with AgHEC synthesis, we prepared a set of sample variants by changing two independent key parameters that affect nucleation and growth steps, thereby impacting the physicochemical properties and the investigated antimicrobial activity. One of the identified design alternatives pointed out an improved antimicrobial activity in the suspension, which was confirmed after application as a coating on nonwoven cellulose fabrics. This enhancement was attributed to a lower particle size distribution and a positive synergistic effect with the HEC matrix.

Antimicrobial efficiency against fish pathogens on the green synthesized silver nanoparticles

Fish-borne pathogens such as A. hydrophila and F. aquidurense are the most resistant strains in pisciculture farming. Removing the aforementioned pathogens without antibiotics presents a formidable challenge. To overcome this problem, silver nanoparticles (AgNPs) are synthesized using silver nitrate, water medium, and as an AzadirachtaIndica leaf extract via the green synthesis route. X-ray diffraction (XRD) pattern results authenticate the synthesized material is the face-centered cubic structure of silver. The optical absorption edge of the synthesized product was found at the wavelength of 440 nm from the UV-visible spectra, which is confirmed to relate to the Surface Plasmon Resonance peaks of silver particles. In addition, the optical band gap value of the synthesized Ag sample is measured to be 2.81 eV from the obtained optical absorption spectra. EDX spectrum of the synthesized product also supports confirming the silver particle formation. The FT-IR spectra of the neem extract and silver nanoparticles showed their characteristic functional groups, respectively. The presence of bands between 1000 cm-1 to 500 cm-1 indicates to the formation of silver particles. Spherical particles appeared in the synthesized Ag using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The particle size of Ag NPs was measured as 40 nm and 62 ± 10 nm by TEM and Dynamic Light Scattering (DLS). The zeta potential was also measured as -12 mV showing the synthesized sample's stable nature. Using the DPPH assay, synthesized AgNPs were taken along with the various concentrations of ascorbic acid (20, 40, 60, 80, and 100 μg/mL) to examine the free radical scavenging activity (RSA). RSA value is higher (84 ± 2 %) for synthesized AgNPs at higher concentration (100 μg/mL) than 21 ± 2 % at low concentration (100 μg/mL). The antimicrobial efficacy of the AgNPs against A. hydrophila and F. aquidurense was performed through the agar diffusion method and its results showed the inhibitory zones of the F.aquidurense and A. hydrophila were measured as 25 ± 3 mm, and 28 ± 4 mm respectively. The synthesized Ag particles showed excellent antimicrobial and antioxidant properties confirmed by antimicrobial and DPPH experiments. It implies that the green synthesized silver nanoparticles could be a good alternative for antibiotics in aquaculture farms. The exposure of low concentrations of silver nanoparticles to zebrafish and brine shrimp does not affect the viability and morphology. The exposure of silver nanoparticles in the fisheries in optimized concentration and time could control the fish-borne pathogens without antibiotics.

Harvesting nucleating structures in nanoparticle crystallization: The example of gold, silver, and iron

The thermodynamics and kinetics of nanoparticle crystallization, as opposed to bulk phases, may be influenced by surface and size effects. We investigate the importance of such factors in the crystallization process of gold, silver, and iron nanodroplets using numerical simulations in the form of molecular dynamics combined with path sampling. This modeling strategy is targeted at obtaining representative ensembles of structures located at the transition state of the crystallization process. A structural analysis of the transition state ensembles reveals that both the average size and location of the critical nucleation cluster are influenced by surface and nanoscale size effects. Furthermore, we also show that transition state structures in smaller nanodroplets exhibit a more ordered liquid phase, and differentiating between a well-ordered critical cluster and its surrounding disordered liquid phase becomes less evident. All in all, these findings demonstrate that crystallization mechanisms in nanoparticles go beyond the assumptions of classical nucleation theory.

Comparative Study of Physicochemical Properties and Antibacterial Potential of Cyanobacteria Spirulina platensis-Derived and Chemically Synthesized Silver Nanoparticles

The "green synthesis" of nanoparticles (NPs) offers cost-effective and environmentally friendly advantages over chemical synthesis by utilizing biological sources such as bacteria, algae, fungi, or plants. In this context, cyanobacteria and their components are valuable sources to produce various NPs. The present study describes the comparative analysis of physicochemical and antibacterial properties of chemically synthesized (Chem-AgNPs) and cyanobacteria Spirulina platensis-derived silver NPs (Splat-AgNPs). The physicochemical characterization applying complementary dynamic light scattering and transmission electron microscopy revealed that Splat-AgNPs have an average hydrodynamic radius of ∼ 28.70 nm and spherical morphology, whereas Chem-AgNPs are irregular-shaped with an average radius size of ∼ 53.88 nm. The X-ray diffraction pattern of Splat-AgNPs confirms the formation of face-centered cubic crystalline AgNPs by "green synthesis". Energy-dispersive spectroscopy analysis demonstrated the purity of the Splat-AgNPs. Fourier transform infrared spectroscopy analysis of Splat-AgNPs demonstrated the involvement of some functional groups in the formation of NPs. Additionally, Splat-AgNPs demonstrated high colloidal stability with a zeta-potential value of (-50.0 ± 8.30) mV and a pronounced bactericidal activity against selected Gram-positive (Enterococcus hirae and Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa and Salmonella typhimurium) bacteria compared with Chem-AgNPs. Furthermore, our studies toward understanding the action mechanism of NPs showed that Splat-AgNPs alter the permeability of bacterial membranes and the energy-dependent H+-fluxes via FoF1-ATPase, thus playing a crucial role in bacterial energetics. The insights gained from this study show that Spirulina-derived synthesis is a low-cost, simple approach to producing stable AgNPs for their energy-metabolism-targeted antibacterial applications in biotechnology and biomedicine.

Size- and Shape-Dependent Interactions of Lipid-Coated Silver Nanoparticles: An Improved Mechanistic Understanding through Model Cell Membranes and In Vivo Toxicity

The widespread use of silver nanoparticles (AgNPs) in various applications and industries has brought to light the need for understanding the complex relationship between the physicochemical properties (shape, size, charge, and surface chemistry) of AgNPs that affect their ability to enter cells and cause toxicity. To evaluate their toxicological outcomes, this study systematically analyzed a series of homogeneous hybrid lipid-coated AgNPs spanning sizes from 5 to 100 nm with diverse shapes (spheres, triangles, and cubes). The hybrid lipid membrane comprises hydrogenated phosphatidylcholine (HPC), sodium oleate (SOA), and hexanethiol (HT), which shield the AgNP surface from surface oxidation and toxic Ag+ ion release to minimize its contribution to toxicity. To reduce any significant effects by surface chemistry, the HPC, SOA, and HT membrane composition ratio was kept constant, and the AgNPs were assessed using embryonic zebrafish (Danio rerio). While a direct comparison cannot be drawn due to the lack of complementary sizes below 40 nm for triangular plates and cubes due to synthetic challenges, significant mortality was observed for spherical AgNPs (AgNSs) of 5, 20, 40, and 60 nm at 120 h postfertilization at concentrations ≥6 mg Ag/L. In contrast, the 10, 80, and 100 nm AgNSs, 40, 70, and 100 nm triangular plate AgNPs (AgNPLs), and 55, 75, and 100 nm cubic AgNPs (AgNCs) showed no significant mortality at 5 days postfertilization following exposure to AgNPs at concentrations up to 12 mg Ag/L. With constant surface chemistry on the AgNPs, size is the dominant factor driving toxicological responses, with smaller nanoparticles (5 to 60 nm) being the most toxic. Larger AgNSs, AgNCs, and AgNPLs from 75 to 100 nm do not show any evidence of toxicity. However, when closely examining sizes between 40 and 60 nm for AgNSs, AgNCs, and AgNPLs, there is evidence that discriminates shape as a driver of toxicity since sublethal responses generally were observed to follow a pattern, suggesting toxicity is most significant for AgNSs followed by AgNPLs and then AgNCs, which is the least toxic. Sum frequency generation vibrational spectroscopy showed that irrespective of size or shape, all hybrid lipid-coated AgNPs interact with membrane surfaces and "snorkel" between phases into the lipid monolayer with minimal energetic cost. These findings decisively demonstrate that not only smaller AgNPs but also the shape of the AgNPs influences their biological compatibility.

Assessing the Potential of Aconitum Laeve Extract for Biogenic Silver and Gold Nanoparticle Synthesis and Their Biological and Catalytic Applications

The adoption of green chemistry protocols in nanoparticle (NP) synthesis has exhibited substantial potential and is presently a central focus in research for generating versatile NPs applicable across a broad spectrum of applications. In this scientific contribution, we, for the first time, examined the ability of Aconitum Laeve (A. Laeve) crude extract to synthesize silver and gold nanoparticles (AgNPs@AL; AuNP@AL) and explored their potential applications in biological activities and the catalytic degradation of environmental pollutants. The synthesized NPs exhibited a distinctive surface plasmon resonance pattern, a spherical morphology with approximate sizes of 5-10 nm (TEM imaging), a crystalline architecture (XRD analysis), and potential functional groups identified by FTIR spectroscopy. The antibacterial activity was demonstrated by inhibition zones that measured 16 and 14 mm for the AgNPs@AL and AuNP@AL at a concentration of 80 µg/mL against Staphylococcus aureus and 14 and 12 mm against Escherichia coli, respectively. The antioxidant potential of the synthesized NPs was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2-Phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-Oxide (PTIO), and 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. Our findings suggest that the AuNP@AL effectively countered the tested radicals considerably, displaying IC50 values of 115.9, 103.54, and 180.85 µg/mL against DPPH, PTIO, and ABTS, respectively. In contrast, the AgNPs@AL showed IC50 values of 144.9, 116.36, and 95.39 µg/mL against the respective radicals. In addition, both the NPs presented significant effectiveness in the photocatalytic degradation of methylene blue and rhodamine B. The overall observations indicate that A. Laeve possesses a robust capability to synthesize spherical nanoparticles, exhibiting excellent dispersion and showcasing potential applications in both biological activities and environmental remediation.

Combat phytopathogenic bacteria employing Argirium-SUNCs: limits and perspectives

Bacterial plant diseases are difficult to control as the durability of deployed control measures is thwarted by continuous and rapid changing of bacterial populations. Although application of copper compounds to plants is the most widespread and inexpensive control measure, it is often partially efficacious for the frequent appearance of copper-resistant bacterial strains and it is raising concerns for the harmful effects of copper on environment and human health. Consequently, European Community included copper compounds in the list of substances candidates for substitution. Nanotechnologies and the application of nanoparticles seem to respond to the need to find new very effective and durable measures. We believe that Argirium-SUNCs®, silver ultra nanoclusters with an average size of 1.79 nm and characterized by rare oxidative states (Ag2+/3+), represent a valid candidate as a nano-bactericide in the control of plant bacterial diseases. Respect to the many silver nanoparticles described in the literature, Argirium-SUNCs have many strengths due to the reproducibility of the synthesis method, the purity and the stability of the preparation, the very strong (less than 1 ppm) antimicrobial, and anti-biofilm activities. In this mini-review, we provide information on this nanomaterial and on the possible application in agriculture. KEY POINTS: • Argirium-SUNCs have strong antimicrobial activities against phytopathogenic bacteria. • Argirium-SUNCs are a possible plant protection product. • Argirium-SUNCs protect tomato plants against bacterial speck disease.

Synergistic Antibacterial Properties of Silver Nanoparticles and Its Reducing Agent from Cinnamon Bark Extract

Synthesis of silver nanoparticles with antibacterial properties using a one-pot green approach that harnesses the natural reducing and capping properties of cinnamon (Cinnamomum verum) bark extract is presented in this work. Silver nitrate was the sole chemical reagent employed in this process, acting as the precursor salt. Gas Chromatography-Mass Spectroscopy (GC-MS), High-Performance Liquid Chromatography (HPLC) analysis, and some phytochemical tests demonstrated that cinnamaldehyde is the main component in the cinnamon bark extract. The resulting bio-reduced silver nanoparticles underwent comprehensive characterization by Ultraviolet-Vis (UV-Vis) and Fourier Transform InfraRed spectrophotometry (FTIR), Dynamic Light Scattering (DLS), Transmission Electron Microscopy, and Scanning Electron Microscopy suggesting that cinnamaldehyde was chemically oxidated to produce silver nanoparticles. These cinnamon-extract-based silver nanoparticles (AgNPs-cinnamon) displayed diverse morphologies ranging from spherical to prismatic shapes, with sizes spanning between 2.94 and 65.1 nm. Subsequently, the antibacterial efficacy of these nanoparticles was investigated against Klebsiella, E. Coli, Pseudomonas, Staphylococcus aureus, and Acinetobacter strains. The results suggest the promising potential of silver nanoparticles obtained (AgNPs-cinnamon) as antimicrobial agents, offering a new avenue in the fight against bacterial infections.

Microwave-assisted synthesis of novel Ti/BTB-MOFs as porous anticancer and antibacterial agents

Nano compounds, especially metal-organic frameworks (MOFs), have significant properties. Among the most important properties of these compounds, which depend on their specific surface area and porosity, are biological properties, such as anticancer and antibacterial properties. In this study, a new titanium/BTB metal-organic framework (Ti/BTB-MOF) was synthesized by using titanium nitrate and 1,3,5-Tris(4-carboxyphenyl)benzene (BTB) under microwave radiation. The structure of the synthesized Ti/BTB-MOF was characterized and confirmed using X-ray diffraction (XRD) patterns, X-ray photoelectron spectroscopy (XPS) analysis, Fourier transform infrared (FT-IR) spectra, energy-dispersive X-ray (EDAX) analysis mapping, scanning electron microscope (SEM) images, thermogravimetric analysis (TGA) curves, and Brunauer-Emmett-Teller (BET) analysis. The in vitro anticancer properties of Ti/BTB-MOF were evaluated using the MTT method against MG-63/bone cancer cells and A-431/skin cancer cells. The in vitro antibacterial activity was tested using the Clinical and Laboratory Standards Institute (CLSI) guidelines. In the anticancer activity, IC50 (half-maximal inhibitory concentration) values of 152 μg/mL and 201 μg/mL for MG-63/bone cancer cells and A-431/skin cancer cells, respectively, were observed. In the antibacterial activity, minimum inhibitory concentrations (MICs) of 2-64 μg/mL were observed against studied pathogenic strains. The antimicrobial activity of Ti/BTB-MOF was higher than that of penicillin and gentamicin. Therefore, the synthesized Ti/BTB-MOF could be introduced as a suitable bioactive candidate.

Infection-Free and Enhanced Wound Healing Potential of Alginate Gels Incorporating Silver and Tannylated Calcium Peroxide Nanoparticles

The treatment of chronic wounds involves precise requirements and complex challenges, as the healing process cannot go beyond the inflammatory phase, therefore increasing the healing time and implying a higher risk of opportunistic infection. Following a better understanding of the healing process, oxygen supply has been validated as a therapeutic approach to improve and speed up wound healing. Moreover, the local implications of antimicrobial agents (such as silver-based nano-compounds) significantly support the normal healing process, by combating bacterial contamination and colonization. In this study, silver (S) and tannylated calcium peroxide (CaO2@TA) nanoparticles were obtained by adapted microfluidic and precipitation synthesis methods, respectively. After complementary physicochemical evaluation, both types of nanoparticles were loaded in (Alg) alginate-based gels that were further evaluated as possible dressings for wound healing. The obtained composites showed a porous structure and uniform distribution of nanoparticles through the polymeric matrix (evidenced by spectrophotometric analysis and electron microscopy studies), together with a good swelling capacity. The as-proposed gel dressings exhibited a constant and suitable concentration of released oxygen, as shown for up to eight hours (UV-Vis investigation). The biofilm modulation data indicated a synergistic antimicrobial effect between silver and tannylated calcium peroxide nanoparticles, with a prominent inhibitory action against the Gram-positive bacterial biofilm after 48 h. Beneficial effects in the human keratinocytes cultured in contact with the obtained materials were demonstrated by the performed tests, such as MTT, LDH, and NO.

Viridibacillus culture derived silver nanoparticles exert potent anticancer action in 2D and 3D models of lung cancer via mitochondrial depolarization-mediated apoptosis

Lung cancer is one of the most commonly occurring cancer types that accounts for almost 2 million cases per year. Its resistance to anticancer drugs, failure of new molecules in clinical trials, severe side-effects of current treatments, and its recurrence limit the success of anticancer therapies. Nanotherapeutic agents offer several advantages over conventional anticancer therapies, including improved retention in tumors, specificity, and anticancer effects at lower concentrations, hence reducing the side-effects. Here, we have explored the anticancer activity of silver nanoparticles synthesized in Viridibacillus sp. enriched culture medium for the first time. Such green nanoparticles, synthesized by biological systems, are superior to chemically synthesized ones in terms of their environmental footprint and production cost, and have one crucial advantage of excellent stability owing to their biological corona. To assess anticancer activity of these nanoparticles, we used conventional 2D cultured A549 cells as well as 3D spheroids of A549 cells. In both models of lung cancer, our silver nanoparticles diminished cell proliferation, arrested DNA synthesis, and showed a dose dependent cytotoxic effect. The nanoparticles damaged the DNA and mitochondrial structures in both A549 cells and A549 spheroids, leading to mitochondrial depolarization and increased cell permeability. Low lethal median doses (LD50) for 2D cultured A549 cells (1 μg/ml) and for A549 spheroids (13 μg/ml) suggest that our nanoparticles are potent anticancer agents. We also developed in vitro tumor progression model and in vitro tumor size model using 3D spheroids to test anticancer potential of our nanoparticles which otherwise would require longer experimental duration along with large number of animals and trained personnel. In these models, our nanoparticles showed strong dose dependent anticancer activity. In case of in vitro tumor progression model, the A549 cells failed to form tight spheroidal mass and showed increased dead cell fraction since day 1 as compared to control. On the other hand, in case of in vitro tumor size model, the 4 and 8 μg/ml nanoparticle treatment led to reduction in spheroid size from 615 ± 53 μm to 440 ± 45 μm and 612 ± 44 μm to 368 ± 62 μm respectively, within the time span of 3 days post treatment. We believe that use of such novel experimental models offers excellent and fast alternative to in vivo studies, and to the best of our knowledge, this is the first report that gives proof-of-concept for use of such novel in vitro cancer models to test anticancer agents such as Viridibacilli culture derived silver nanoparticles. Based on our results, we propose that these nanoparticles offer an interesting alternative for anticancer therapies, especially if they can be combined with classical anticancer drugs.

Biosynthesis and assessment of antibacterial and antioxidant activities of silver nanoparticles utilizing Cassia occidentalis L. seed

This research explores the eco-friendly synthesis of silver nanoparticles (AgNPs) using Cassia occidentalis L. seed extract. Various analytical techniques, including UV-visible spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive X-ray spectroscopy (EDX), were employed for comprehensive characterization. The UV-visible spectra revealed a distinct peak at 425 nm, while the seed extract exhibited peaks at 220 and 248 nm, indicating the presence of polyphenols and phytochemicals. High-resolution TEM unveiled spherical and oval-shaped AgNPs with diameters ranging from 6.44 to 28.50 nm. The SEM exhibiting a spherical shape and a polydisperse nature, thus providing insights into the morphology of the AgNPs. EDX analysis confirmed the presence of silver atoms at 10.01% in the sample. XRD results unequivocally confirm the crystalline nature of the AgNPs suspension, thereby providing valuable insights into their structural characteristics and purity. The antioxidant properties of AgNPs, C. occidentalis seed extract, and butylated hydroxytoluene (BHT) were assessed, revealing IC50 values of 345, 500, and 434 μg/mL, respectively. Antibacterial evaluation against Bacillus subtilis, Staphylococcus aureus, and Escherichia coli demonstrated heightened sensitivity of bacteria to AgNPs compared to AgNO3. Standard antibiotics, tetracycline, and ciprofloxacin, acting as positive controls, exhibited substantial antibacterial efficacy. The green-synthesized AgNPs displayed potent antibacterial activity, suggesting their potential as a viable alternative to conventional antibiotics for combating pathogenic bacterial infections. Furthermore, potential biomedical applications of AgNPs were thoroughly discussed.

Extremely Monodispersed Micrometer-Scale Spherical Particle Synthesis of Ag Inside a Microdroplet Vaporizing in Plasma

Spherical Ag particles have received considerable attention because of their unique properties as well as their applications in various fields. In the present study, the synthesis of micrometer-scale spherical Ag particles with an extremely narrow size distribution is demonstrated using a simple capacitively coupled atmospheric-pressure plasma reactor with an inkjet head. Droplets of a Ag nitrate aqueous solution are ejected from the inkjet head to synthesize Ag particles. The gaseous temperature in the reactor is adjusted such that Ag can be melted with a negligibly small vapor pressure. These particles exhibit a spherical shape with a smooth surface. The mean diameter of the particles is 0.91 ± 0.013 μm with a small coefficient of variation of 1.5%, the smallest value ever reported for Ag particles of less than 1 μm. The grain sizes of the particles are larger than 100 nm, as expected from the broadening of the X-ray diffraction peaks. The excellent monodispersity of the particles synthesized by this method may expand the applications with micrometer-scale spheres such as ball spacer, microsized ball bearing, and inks for printed electronics.

Cytotoxic activity of bimetallic Ag@Se green synthesized nanoparticles using Jerusalem Thorn (Parkinsonia aculeata)

Introduction: The process of green synthesis of metal nanoparticles is considered to be eco-friendly and cost-effective. Methods: In this study, bimetallic Ag@Se-P and Ag@Se-S nanoparticles were synthesized successfully using Parkinsonia aculeata aerial parts and seed extracts. The phytochemical contents in P. aculeata aerial parts and seed aqueous extract serve as reducing and stabilizing capping agents without the need for any chemical stabilization additive in the synthesis of bimetallic nanoparticles. Result and Discussion: The obtained results from UV-vis spectrophotometry, scanning electron microscopy (SEM), X-ray powder diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FT-IR) confirmed the successful synthesis of bimetallic nanoparticles with cluster irregular spherical morphology, crystalline nature, and average particle sizes of 17.65 and 24.36 nm for Ag@Se-S and Ag@Se-P, respectively. The cytotoxicity assessment of greenly synthesized nanomaterials using seed and plant extracts showed cell inhibition >50 μg/mL. Ag@Se-S and Ag@Se-P seed and plant extracts significantly reduced LPS-induced inflammation, which was assessed by NO and cytokines IL-1β, IL-6, and TNF-α. The mRNA and protein expression levels of phosphoinositide 3 kinase (PI3K) and nuclear factor kappa B (NFkB) were significantly overexpressed in LPS-induced RAW 264.7 cell lines. Ag@Se-S and Ag@Se-P downregulated the expression of PI3K and NFkB in LPS-induced cell models.

Bio-reductive synthesis of silver nanoparticles, its antibacterial efficiency, and possible toxicity in common carp fish (Cyprinus carpio)

The biological synthesis of nanoparticles is an emerging field of study that seeks to synthesize nanoparticles using non-chemical mechanisms such as microorganisms, plants, and animal blood serum. Among these, plants have gained particular attention due to their ease of handling, availability, and ability to synthesize a wide range of nanoparticles. Therefore, the current study aimed to fabricate the silver nanoparticles (AgNPs) using Chinese medicinal plants (CMP) for their possible toxicity in common carp fish (Cyprinus carpio). For this purpose, CMP was dried, ground, and used as a bio-reductive agent. The fabricated AgNPs were characterized and a well dispersed AgNPs were obtained. Moreover, the C. carpio was exposed to the AgNPs for bioaccumulation and histological alterations. The obtained findings revealed that the AgNPs were mostly accumulated in the intestines followed by the gills, muscles, liver, and brain. The accumulated AgNPs caused histological alterations in gills and intestines at the highest concentration (0.08 mg/L). However, very less alterations were caused by the lowest concentration, especially in the intestine. In conclusion, further in-depth research is needed to determine the risks associated with the usage of nanoparticles to reveal their harmful impacts on fish and the aquatic environment. HIGHLIGHTS: The biological fabrication of AgNPs is considered eco-friendly. Chinese medicinal plants play a significant role in AgNPs synthesis. AgNPs have excellent antibacterial activity. AgNPs are bioaccumulated in various organs of fish.