Synthesis Of AgNPs Research Articles

Biosynthesized Silver Nanoparticles from Cyperus conglomeratus Root Extract Inhibit Osteogenic Differentiation of Immortalized Mesenchymal Stromal Cells.

Silver nanoparticles (AgNPs) are a focus of huge interest in biological research, including stem cell research. AgNPs synthesized using Cyperus conglomeratus root extract have been previously reported but their effects on mesenchymal stromal cells have yet to be investigated. The aim of this study is to investigate the effects of C. conglomeratus-derived AgNPs on adipogenesis and osteogenesis of mesenchymal stromal cells. AgNPs were synthesized using C. conglomeratus root extract, and the phytochemicals involved in AgNPs synthesis were analyzed using gas chromatography-mass spectrometry (GCMS). The cytotoxicity of the AgNPs was tested on telomerase-transformed immortalized human bone marrow-derived MSCs-hTERT (iMSC3) and human osteosarcoma cell line (MG-63) using MTT and apoptosis assays. The uptake of AgNPs by both cells was confirmed using inductively coupled plasma-optical emission spectrometry (ICP-OES). Furthermore, the effect of AgNPs on iMSC3 adipogenesis and osteogenesis was analyzed using stain quantification and reverse transcription- quantitative polymerase chain reaction (RT-qPCR). The phytochemicals predominately identified in both the AgNPs and C. conglomeratus root extract were carbohydrates. The AgNP concentrations tested using MTT and apoptosis assays (0.5-64 µg/ml and 1,4 and 32 µg/ml, respectively) showed no significant cytotoxicity on iMSC3 and MG-63. The AgNPs were internalized in a concentration-dependent manner in both cell types. Additionally, the AgNPs exhibited a significant negative effect on osteogenesis but not on adipogenesis. C. conglomeratus-derived AgNPs had an impact on the differentiation capacity of iMSC3. Our results indicated that C. conglomeratus AgNPs and the associated phytochemicals could exhibit potential medical applications.

Fabrication of electrospun PA66 nanofibers loaded with biosynthesized silver nanoparticles: investigation of dye degradation and antibacterial activity.

In the current study, silver nanoparticles (AgNPs) incorporated Polyamide 66 (PA66) nanofiber mat as a photocatalyst which was prepared using electrospinning technique for degradation of methyl orange (MO). Considering the lack of reported studies on the influence of the ultrasonication on the size and stability of AgNPs, the purpose of the study was to produce a small size of AgNPs and compare it with the continuous stirring method. It is reasonable to report that the advantage of ultrasonication is to generate relatively smaller AgNPs (u-AgNPs) compared to fabrication by continuous stirring method (s-AgNPs). Helichrysum arenarium (HA) extract was used as a reducing agent as well as a capping agent in green synthesis of AgNPs. AgNPs were characterized by UV-visible spectrophotometry, Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and transmission electron microscope (TEM). PA66/u-AgNs nanofibers were then successfully electrospun and characterized by using scanning electron microscope (SEM), FT-IR, thermal gravimetric analysis (TGA), and water contact angle measurement (WCA). Fabricated PA66-based nanofiber mat with smooth surface and uniform diameters (330-340nm) was used as a catalyst in MO degradation. PA66/u-AgNP nanofibers were also evaluated for antibacterial performance and showed significant inhibition against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa bacteria. According to these findings, it is expected that the fabricated novel PA66/u-AgNP nanofibers can be announced as a promising potent and applied to the wastewater applications.

From Ficus recemosa Leaf Galls to Therapeutic Silver Nanoparticles: Antibacterial and Anticancer Applications.

The synthesis of silver nanoparticles (AgNPs) using environmentally friendly methods has become increasingly important due to its sustainability and cost-effectiveness. This study investigates the green synthesis of AgNPs using gall extracts from the plant Ficus recemosa, known for its high phytochemical content. The formation of AgNPs was verified through multiple analytical techniques, including UV-Vis spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), zeta potential analysis, and dynamic light scattering (DLS). The UV-Vis spectroscopy results displayed a distinct surface plasmon resonance peak indicative of AgNP formation. FTIR analysis revealed specific interactions between silver ions and phytochemicals in the gall extract, while TEM images confirmed the nanoscale morphology and size of the synthesized particles. Zeta potential and DLS analyses provided insights into the stability and size distribution of the AgNPs, demonstrating good colloidal stability. Biological properties of the AgNPs were assessed through various assays. Antimicrobial activity was tested using the disc diffusion method against Escherichia coli and Staphylococcus aureus, showing significant inhibitory effects. The anticancer potential was evaluated using the trypan blue exclusion assay on Dalton's Lymphoma Ascites (DLA) cells, revealing considerable cytotoxicity. Additionally, antimitotic activity was studied in the dividing root cells of Allium cepa, where the AgNPs significantly inhibited cell division. This research highlights the effective use of F. recemosa gall extracts for the green synthesis of AgNPs, presenting an eco-friendly approach to producing nanoparticles with strong antimicrobial, anticancer, and antimitotic properties. The promising results suggest potential applications of these biogenic AgNPs in medical and agricultural sectors, paving the way for further exploration and utilization.

Biofouling control of thermophilic bacteria in membrane distillation

Previously, fouling of MD membranes was perceived to be minimal due to the operational conditions preventing bacterial growth. However, recent studies presented fouling of MD membranes, largely due to various halophilic and thermophilic bacterial. The current study presented potential of antibacterial cellulose nanocrystals (CNCs) capped silver nanoparticles (AgNPs) towards biofouling control in MD water desalination processes. Interestingly, the CNCs were used as capping and reducing agent in a microwave mediated synthesis of AgNPs. The green synthesis approach of AgNPs and its successful use in MD processes was reported for the first. The MD experiments were carried out using a series of modified PVDF membranes and feed solution spiked with a thermophilic G. stearothermophilus. Upon evaluation of fouled membranes, particularly PVDF, PVP-equipped PVDF, and f-CNTs-modified PVDF, the surface energy of interactions were −131 mJ/m2, −31.5 mJ/m2, −28.6 mJ/m2, suggesting favorable interaction between the membranes and bacterial foulant. The findings of this study were supported by fouling layer and bacterial growth as seen from scanning electron microscopy, atomic force microscopy and Fourier transform infrared results. Upon membrane surface modification using CNCs-capped AgNPs, bacterial growth on membrane surface was reduced. Specifically, the positive cohesion energy between the CNCs-capped AgNPs-modified PVDF membrane and thermophilic bacterial foulant was + 63.2 mJ/m2, distinctly proving reduced fouling. The findings were supported by 5.5 % flux decay of the modified membrane compared to 79.3 % flux decay of virgin PVDF membrane. This suggested a long-term membrane integrity in thermophilic bacterial contaminated feed solutions during the MD water desalination.

Development of AgNPs-PVP/TPU based flexible strain sensors for structural health monitoring of composite structures

Real-time in-stu structural health monitoring (SHM) of composite structure developed through highly sensitive and flexible smart sensors based on colloidal solution of Silver Nano Particles (AgNPs). Synthesis of AgNPs through chemical reduction method by citrate and then in Haxen phase transferred by using surfactant Cetyltrimethylammonium bromide (CTAB). Colloidal solution of AgNPs-Haxen and Polyvinylpyrrolidone (PVP) - Haxen has been followed by mixed, calcined and deposited that thick paste on flexible Thermoplastic Polyurethane (TPU) film. These sensors become more sensitive than metallic foil made sensors and farther this sensor pasted on polymer composite for monotonic loading like tensile loading. The data extracted from sensors was monitored effectively by data acquisitioning technique using Keithley KUSB-3100. This research based on chemical synthesis of metallic nanoparticles like silver, its functionalization, protection of these nanoparticles from environment by capping agents and by creating inert atmosphere respectively. Then these functionalized capped nanoparticles are embedded on the surface of thermoplastic Urethane (TPU) film to make piezo resistive semi conductive strips which serve as flexible strain gauge/smart sensor. One other technique is also being used to make sensor is that colloidal solution of metallic Nanoparticles sprays over TPU substrate using Connective Self Assembly (CSA) method. The sensor then properly attached to Glass fabric reinforced polymer (GFRP) composite and calibrated using data acquisitioning (DAQ) under different mode of testing.

Biosynthesis of Silver and Gold Nanoparticles Using Geum urbanum L. Rhizome Extracts and Their Biological Efficiency

AbstractThe present study evaluates the biosynthesis of AgNPs and AuNPs using aqueous and ethanolic Geum urbanum L. rhizome extracts. The biosynthesized metal nanoparticles (MNPs) were characterized using UV-Vis spectroscopy, FTIR, DLS, SEM, EDX, and TEM. The UV-Vis spectra confirmed the synthesis of AgNPs and AuNPs through peaks corresponding to the surface plasmon effect of metallic Ag (400–430 nm) and Au (530–570 nm). FTIR analysis indicated that alcohols, phenols, proteins, and carbohydrates from G. urbanum rhizome extracts composition are involved in MNPs synthesis. In DLS analysis, AgNPs (34.26–41.14 nm) showed smaller hydrodynamic diameters than AuNPs (46.26–70.29 nm). At the same time, all values for zeta potential were negative, between − 21 and − 13 mV, suggesting good stabilities for all the colloidal MNPs systems in dispersion. TEM analysis showed that the biosynthesized AgNPs had a spherical morphology, while AuNPs were quasi-spherical, polygonal, and triangular. According to TEM data, AgNPs synthesized using aqueous and ethanolic G. urbanum rhizome extracts were characterized by mean diameters of 9.82 ± 3.68 and 14.29 ± 3.46 nm, while AuNPs by 15.88 ± 6.28 and 24.89 ± 10.75 nm, respectively. EDX analysis confirmed the presence of metallic Ag and Au in the MNPs composition by detecting strong signals at 3 (AgNPs) and 2.2 keW (AuNPs). In disc diffusion assay, MNPs showed good antimicrobial activity against Gram-positive (S. aureus MSSA, S. aureus MRSA, S. epidermidis) and Gram-negative (E. coli, P. aeruginosa, K. pneumoniae) bacteria and yeasts (C. albicans). AgNPs and AuNPs were also characterized by a significant antioxidant potential, evaluated through in vitro assays (lipoxygenase inhibition, DPPH radical scavenging activity, metal ion chelating activity, and hydroxyl radical scavenging assays). An overall better activity was obtained for the ethanolic G. urbanum rhizome extract and its derived AgNPs (EC50 = 34.2 ± 1.86 mg/mL in lipoxygenase inhibition assay). Therefore, the G. urbanum rhizome extracts proved to be excellent sources for biologically active AgNPs and AuNPs.

Pomegranate’s silver bullet: Nature-powered nanoparticles deliver a one-two punch against cancer and antimicrobial resistance

Biogenic synthesis for producing silver nanoparticles (AgNPs) leverages natural extracts, offering an eco-friendly and biocompatible alternative to traditional chemical methods. Pomegranate (Punica granatum L. (PG)) extract, rich in phytochemicals, presents a valuable resource for this green synthesis approach. The primary objective is to harness the natural phytochemicals in PG extract to create stable, biocompatible AgNPs through a green synthesis method. Our study aims to explore the synthesis and characterization of AgNPs derived from PG using eco-friendly methods. In addition, this study investigates the antioxidant, antimicrobial, and anticancer properties of PG-AgNPs. The preparation of PG followed by the reduction of AgNO3 to PG-AgNPs, with subsequent characterization using UV–Vis spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). These techniques confirmed the successful synthesis of AgNPs with desirable size, shape, and stability. Further, antimicrobial properties, antioxidants, cytotoxicity assay, and ADME prediction were also assessed. The PG-AgNPs revealed no signs of aggregates, suggesting they could maintain their original shape. In addition, XRD analysis indicates that PG-AgNPs are highly pure. The zeta potentials of the biosynthesized PG-AgNPs were −17.8 ± 6.57 mV. AgNPs exhibited FTIR peaks associated with silanols, carboxylates, phosphonates, and siloxanes. The PG-AgNPs exhibited potent antibacterial activity against E. coli and Klebsiella pneumoniae, with higher efficacy than PG extract alone. Additionally, PG-AgNPs demonstrated significant antioxidant activity comparable to or exceeding that of ascorbic acid. The AgNPs effectively inhibited the growth of liver (HepG2), breast (MDA-MB-231), and cervical (HeLa) cancer cells in a dose-dependent manner while showing no toxicity to normal human cells (WI-38). The study concludes that biogenically synthesized PG-AgNPs possess potent anticancer and antimicrobial properties, highlighting their potential as therapeutic agents. The green synthesis method underscores the advantages of eco-friendly approaches in developing effective nanomaterials, paving the way for novel treatments in cancer therapy and combating antibiotic-resistant infections.

Biosynthesis of silver nanoparticle from flower extract of Dillenia indica and its efficacy as antibacterial and antioxidant

Dillenia indica is a medicinal tree of the Dilleniaceae and its flower extract was used for the synthesis of silver nanoparticle (AgNPs). The optimal conditions for AgNPs synthesis were as such: 2 mM AgNO3, pH 4.5 and 48-h reaction time. The characteristic band of AgNPs was observed at the wavelength of 435 nm by UV–visible spectroscopic study. Fourier-transform infrared (FTIR) analysis depicted the involvement of several functional groups of plant extracts in the synthesis of AgNPs. Nanoparticles were mostly spherical shaped and uniformly distributed, when observation was made by Transmission electron microscopy (TEM). Energy Dispersive X-Ray (EDX) showed absorption peak approximately at 3 keV thus confirmed the presence of silver metal in AgNP. X-ray diffraction (XRD) investigation and selected area electron diffraction (SAED) patterns showed the crystalline nature of the AgNPs. Dynamic light scattering (DLS) analysis exhibited average size of the nanoparticles as 50.17 nm with a polydispersity index (PDI) value of 0.298. The zeta potential of nanoparticles was observed as −24.9 mV. To assess antibacterial activity, both AgNPs alone or its combination with the antibiotic were tried against six pathogenic bacteria. The combination of AgNPs with antibiotic was maximum effective against Shigella boydii (16.07 ± 0.35) and Klebsiella pneumoniae (15.03 ± 0.20). AgNPs alone showed maximum inhibition for both Gram-positive bacteria: methicillin-resistant Staphylococcus aureus (19.97 ± 0.20 mm) and Enterococcus faecium (19.80 ± 0.15 mm). Maximum inhibition of Enterobactor cloacae and Pseudomonas aeruginosa was observed by antibiotic taken alone. Evaluation through 2,2-diphenyl-1-picrylhydrazyl (DPPH) and DNA nicking assays demonstrated the antioxidant capabilities of the nanoparticles.

Evaluation of antimicrobial and anticancer efficacy of silver nanoparticles phytofabricated by Nyctanthes arbor-tristis L. leaf extract

Nyctanthes arbor-tristis L. (Oleaceae), commonly known as harsingar, is a plant with potential medicinal properties. The plant was used in traditional folk medicine and as a pharmacological activity. The present study reports a rapid and eco-accommodating technique to synthesize silver nanoparticles AgNPs with low cost and with no need to heat, using aqueous extracts of N. arbor-tristis L. Phytochemical analysis was conducted to detect the existence of alkaloids, flavonoids, saturated sugar, saponins, glycosides, steroids, tannins, terpenoids, and proteins in the plant. A color change observed in the test confirmed the synthesis of AgNPs. SEM, XRD, EDX, FTIR, and UV – Visible spectrophotometer (DLS) were used to characterize the synthesized AgNPs. The antibacterial potential of AgNPs was further tested against different bacterial strains such as Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Staphylococcus aureus and Klebsiella pneumonia displayed by finding the maximum zone of inhibition observed against S. typhi of 24.6 mm, S. aureus 21.6±0.57 mm, P. aeruginosa 19 mm, K. pneumonia 17 mm and E. coli 15.3±0.57 mm. Furthermore, the synthesized AgNPs were also exhibited as anticancer properties against MDA-231 cell line Human Breast cancer cell line which was determined dose dependent manner and their concentration of 2.5 to 30 μg/mL respectively, and noted the inhibitory range at 30 μg/mL of its concentration, which was further tested in high inhibitory effect on their leaf extract high concentration in cytotoxic, bactericidal experiments.

Synthesis of Silver Nanoparticles Using Azadirachta indica and Syzygium aromaticum Extract and Its Antibacterial Action Against Enterococcus faecalis: An In Vitro Study.

Introduction Nanotechnology is the study of manipulating matter at the atomic scale involving particles smaller than 100 nm. Silver nanoparticles (AgNPs) are gaining popularity across diverse sectors including medical, food, healthcare, consumer goods, and industrial fields due to their distinctive physical and chemical characteristics. The eco-friendly synthesis of AgNPs offers a straightforward, cost-effective, and environmentally benign method devoid of hazardous chemicals. Methodology Eighty milliliters (mL) of silver nitrate mixed with 20 mL of Azadirachta indica and Syzygium aromaticum plant extract underwent two days of magnetic stirring for AgNP synthesis. Characterization was done via ultraviolet-visible (UV-vis)-spectroscopy (300-700 nm), and antimicrobial properties, which were checked with Enterococcus faecalis, were assessed using the agar-well diffusion method. Results The change in color and peak observed in the UV-vis spectrum confirmed the successful synthesis of AgNPs. Both neem and clove extract-mediated synthesis of AgNPs exhibited antibacterial activity against E. faecalis. However, neem extract synthesized AgNPs displayed a larger inhibitory zone diameter and lower minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values compared to those synthesized using clove extract. Conclusion Incorporating neem and clove extracts in AgNP synthesis offers a practical, eco-friendly, and cost-efficient method with notable efficacy. These AgNPs exhibit antibacterial activity against E. faecalis, suggesting their viability as potent antibacterial agents for addressing oral pathogens. Their sustainable synthesis underscores a promising avenue for developing effective antimicrobial solutions in oral healthcare.

Eco-friendly synthesis of N- cholyl mercapto histidine capped silver nanoparticles and its sensing of mercury (II) ions and photo catalytic degradation of methyl orange

In this report, we have developed highly water soluble and stable silver nanoparticles (Ag NPs) utilizing N-Cholyl Mercapto Histidine (NCMH) as a reducing and stabilizing agent with near the primary critical micellar concentration (CMC) under ambient sunlight irradiation. Moreover, The NCMH was firstly synthesized by demonstrating the reaction between cholic acid and 2- Mercapto Histidine through a simple acid amine coupling approach. The primary and secondary CMC of NCMH surfactant was measured by pyrene (1 × 10−6 M) as a fluorescent probe, and values were found to be 3.2 and 13.1 mM respectively. The synthesized Ag NPs showed at neutral pH and highly stable for more than one year without any noticeable aggregation. The TEM analysis displays the synthesized Ag NPs having a spherical shape and average size of 9.6 ± 0.5 nm. The synthesis of stabilized Ag NPs was used for ultra-sensitive and selective detection of Hg2+ ions in aqueous medium were monitored by Uv–visible spectrometer and naked eyes with a lowest limit of detection (LOD) 7 nM. The photo-catalytic degradation of methyl orange (MO) by utilizing Ag NPs as nano-catalyst exhibits a potential degradation within a study period of 180 min. Concluding that, facile and cost effective green synthesis of NCMH capped Ag NPs possess excellent reducing ability towards the selective detection of Hg2+ ions along with photo-catalytic degradation of MO dye. These true findings detached an innovative pathway of Ag NPs towards the reactivity against the catalytic activity of dye degradation and selective sensing of Hg2+ ions. Thus it paves the way for extensive range of novel potential applications of Ag NPs in various environment friendly approaches of sensitive and analytical protocol in the future.

Application of AgNPs in biomedicine: An overview and current trends

Abstract Silver nanoparticles (AgNPs) can provide excellent, reliable, and effective solutions for anti-microbial, drug-loading, and other purposes due to their extraordinary physical, chemical, and biological characteristics. Different methods have been used in the synthesis and characterization of AgNPs, and AgNPs have been applied in various fields of biomedicine, including dentistry, oncology, diabetology, neurodegenerative disorders, and so on. However, the cytotoxicity of AgNPs has not been solved during their application, making them controversial. The aim of this review is to summarize the capabilities, synthesis, and characterization methods, and the application of AgNPs in various biomedicine fields. In addition, the toxicity of AgNPs is explicated, and the methods of enhancing the benefit properties and reducing the toxicity of AgNPs are demonstrated. In the end, the perspective of AgNPs’ research and application are proposed for the great potential in biomedicine contributing to human health.

Green Formulation of Descurainia sophia Aqueous Extract Mediated Ag NPs and Determination of Its Anti-Hemangioma Effects

Hemangioma is a common cancer with severe clinical signs. Finding a new anti-hemangioma supplement or drug inside of the chemotherapeutic drug is valuable. We synthesized silver nanoparticles containing Descurainia sophia leaf for investigating the anti-hemangioma, cytotoxicity, and antioxidant effects. Characterization of AgNPs was performed by Field Emission Scanning Electron Microscopy (FE-SEM), UV–Visible Spectroscopy (UV-Vis), and X-Ray diffraction analysis (XRD). The plain peak in the wavelength 449 nm revealed the AgNPs synthesis. TEM and FE-SEM analyses showed that synthesized AgNPs were found to be 16.9 to 48.43 nm mean particle size. For investigating the antioxidant efficacy, the DPPH assay was conducted. AgNPs prevented 50% of DPPH in the dilation of 40 μg/mL. To measure the anti-hemangioma efficacy of AgNPs, MTT assay was applied on SK HEP-1 and HAEND cell lines. AgNPs had high anti-hemangioma efficacy on above tumor cells without any significant toxicity on HUVEC. The best finding of anti-hemangioma properties of AgNPs was seen in the case of the HAEND cell line. This study indicated significant anti-hemangioma and antioxidant potentials of AgNPs containing Descurainia sophia.

In Ukrainian

Due to the variety of their forms and properties, silver nanoparticles (AgNPs) are promising for obtaining nanomaterials with various functional applications. Today, regardless of the method of obtaining AgNPs, there is a problem of stabilizing their surface to prevent aggregation, which significantly reduces their activity and prevents uniform distribution during the preparation of nanomaterials. The aim of this work was the synthesis of silver nanoparticles using an oligomeric ionic liquid (OIL) and the study of their structure and antimicrobial properties. In this work, for the first time, an anionic OIL with a hyperbranched structure developed by us was used as a surface stabilizer in the synthesis of AgNPs. The synthesis of AgNPs was carried out by the reduction of Ag ions in the composition of AgNO3 with trisodium citrate in the presence of this OIL. Using the methods ofUV-vis and FTIR spectroscopy, X-ray analysis, electron microscopy and the disc-diffusion method, the peculiarities of the structural organization of AgNPs and their antimicrobial properties were studied. UV-visible spectroscopy data indicate the formation of silver nanoparticles and their spherical or quasi-spherical shape. It was found that there are adsorbed ionic and carbonyl groups on the surface of the formed AgNPs, and the formation of host-guest complexes between OIL and silver ions was revealed using FTIR. The formation of AgNPs and complexes between OIL and silver ions is also confirmed by X-ray diffraction. According to electron microscopy, the size of the synthesized nanoparticles varies from 5 to 16 nm, with an average value of 10.2 nm. This average value is very close to the value of 9.3 nm obtained from the results of X-ray analysis. The synthesized silver nanoparticles showed a very high antimicrobial activity against C. albicans fungi, while the width of the inhibition zone (d) was 34 mm. Also, the AgNPs powder shows very high activity against gram-positive bacteria S. aureus (d = 30 mm) and gram-negative bacteria E. coli (d = 12 mm). The approach developed by us to the synthesis of AgNPs in the presence of OIL as a surface stabilizer with certain functionalization of the latter opens up new opportunities in the synthesis of AgNPs and the preparation of highly dispersed related systems, including functionalized nanocomposite polymer materials with antimicrobial properties.

Green synthesis of Carica papaya mediated silver nanoparticles: Characterization, antibacterial activity, and bioelectricity generation for sustainable applications in nanotechnology

This study presents a sustainable method for synthesizing silver nanoparticles (Ag NPs) using green Carica papaya extract (CPE) as a reducing and stabilizing agent. The green synthesis minimizes environmental impact and utilizes bioactive compounds in Carica papaya (CP), offering an economical and sustainable alternative. The goal is to employ CPE for the eco-friendly synthesis of Ag NPs, followed by comprehensive characterization, antibacterial evaluation, cytotoxicity against brine shrimp, and examination of bioelectricity generation. Locally sourced CP was boiled in deionized water, then cooled and filtered twice. The bio-reduction of silver ions to Ag NPs was confirmed by a color change when 45 mL of 0.005 M AgNO3 was mixed with 5 mL of CPE. Characterization through UV–vis absorption spectrophotometry (UV), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray spectroscopy (EDX), Transmission electron microscopy (TEM), and Gas chromatography-mass spectrometry (GC–MS) analysis confirms the successful formation and consistent size distribution of Ag nanoparticles. CPE is a crucial reducing agent, as evidenced by a distinct UV-visible peak at 422 nm. X-ray crystal analysis verifies highly crystalline Ag NPs with a face-centered cubic lattice structure. The d-spacing values in SAED images are consistent with the results obtained from XRD. Antimicrobial effectiveness against Escherichia coli and Staphylococcus epidermidis is demonstrated. The study explores the bioelectricity generation potential of CPE-synthesized Ag NPs, indicating promising prospects for sustainable energy solutions. Preliminary experiments show the ability of the nanoparticles to catalyze bio-electrochemical reactions. This dual-benefit study underscores CPEs role in antibacterial properties and bioelectricity generation, laying the groundwork for further research in sustainable nanotechnology applicable to healthcare and energy sectors and contributing to the advancement of environmentally friendly technologies.

Green Synthesis of Antimicrobial Silver Nanoparticles using Green Tea Extract: The Role of Concentration and pH

ABSTRACTGreen synthesis for silver nanoparticles (AgNPs) is the process of reducing Ag+ ions to Ag0 by using plant bioactive compounds. Green synthesis is safer, environmentally friendly and cost-effective. Plant bioactive compounds from Camellia sinensis L. (green tea) extract containing polyphenols can be used as a reducer in the formation of silver nanoparticles. This study aims to determine the effect of pH (8, 9, and 10), at 1,5mM AgNO3 concentration and 0,75% green tea extract concentration on the physical characteristics and antibacterial activity of silver nanoparticles prepared by green synthesis method. The synthesized results were evaluated by UV-Vis Spectrophotometer, Dynamic Light Scattering (DLS), SEM, and FTIR. The optimal AgNP synthesis process resulted from the AgNO3 concentration of 1.5 mM with 0.75% green tea extract at pH 10 which showed an absorbance value of 4,420 at λ 435,3 nm, with a particle size of 47,1 nm and a PDI of 0,243. The formation of AgNPs was observed by a change in color to brownish yellow. Antibacterial activity of AgNPs using liquid diffusion method. The results obtained AgNPs for Staphylococcus aureus bacteria has had inhibition at a concentration of 0,187mM and Escherichia coli at a concentration of 0,375mM.Keywords: Silver nanoparticles; green synthesis; green tea extract; pH; antibacterial activity

Preparation of Green Silver Nanoparticles and Eco-Friendly Polymer-AgNPs Nanocomposites: A Study of Toxic Properties across Multiple Organisms.

This article focuses on the eco-friendly (green) synthesis of silver nanoparticles (AgNPs) and their incorporation into a polymer matrix. For AgNPs synthesis, Lavandula angustifolia (lavender) leaf extract was used as a reducing and stabilizing agent, and as a silver precursor, AgNO3 solution with different concentrations of silver (50, 100, 250, and 500 mg/L) was used. Prepared AgNPs colloids were characterized using UV-vis spectrophotometry, transmission electron microscopy (TEM), and X-ray diffraction (XRD). The spherical morphology of AgNPs with an average size of 20 nm was confirmed across all samples. Further, the antimicrobial properties of the AgNPs were evaluated using the disk diffusion method on algae (Chlorella kessleri) and the well diffusion method on bacteria (Staphylococcus chromogenes, Staphylococcus aureus, and Streptococcus uberis), along with root growth inhibition tests on white mustard (Sinapis alba). Polymer composite (PVA-AgNPs) was prepared by incorporation of AgNPs into the polymer matrix. Subsequently, non-woven textiles and thin foils were prepared. The distribution of AgNPs within the nanocomposites was observed by scanning electron microscopy (SEM). Antibacterial properties of PVA-AgNPs composites were analyzed on bacteria Streptococcus uberis. It was found that not only AgNPs showed good antimicrobial properties, but toxic properties were also transferred to the PVA-AgNPs nanocomposite.

Evaluation of the Effect of Different Extraction Temperatures on the Synthesis of Silver Nanoparticles from Ocimum basilicum (Basil) Plant

The eco-friendly green synthesis of silver nanoparticles (AgNPs) using Ocimum basilicum (basil) extract at varying extraction temperatures (40°C, 60°C, 80°C, 100°C) was investigated to determine the optimal conditions for nanoparticle formation. Analysis methods such UV-Vis spectrophotometry, Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and TransmissionElectron Microscopy (TEM) confirmed the crystalline, spherical nature of AgNPs and identified phytochemicals acting as capping and reducing agents. Notably, the extraction temperature was found to influence both the DPPH radical scavenging activity and the structural properties of AgNPs. According to TEM analysis results, it was observed that high extraction temperatures increased the nanoparticle formation efficiency but created a wide size distribution. The crystallite sizes, calculated using the Scherrer equation, for AgNPs synthesized at different extraction temperatures, were determined to be 12.45 nm, 18.77 nm, 17.76 nm, and 16.03 nm, respectively. The hydrodynamic sizes of the AgNPs were found to range between 158.1 and 333.7 nm. The study highlights the critical role of extraction temperature in the synthesis process, suggesting 40°C as the optimal temperature for achieving efficient and environmentally friendly synthesis of AgNPs with enhanced biological activities.

Anticancer, antioxidant, and antimicrobial activities of nanoemulsions based on water-in-olive oil and loaded on biogenic silver nanoparticles

Abstract Nanoemulsions (NEMs) are more stable and permeable than regular emulsions because of their increased surface area and smaller particle sizes, which are stabilized by emulsifiers and consist of nanometer-sized droplets. Utilization of an olive oil nanoemulsion (NEM-olive oil) loaded with silver nanoparticles (Ag-NPs) derived from marine alga Turbinaria turbinata may be effective against microorganisms and cancer cell lines. NEM-olive oil was made by mixing olive oil, surfactant (Span:Tween (28:72)), and D water (1:4:5). The marine alga Turbinaria turbinata was used for the synthesis of Ag-NPs (Tu-Ag-NPs), and combined with NEM-olive oil (1:1) to synthesize Ag-NPs loaded in olive oil–water nanoemulsion (Ag/NEM-olive oil). Transmission electron microscopy, energy-dispersive X-ray analysis, zeta potential, Fourier transform infrared, and X-ray powder diffraction spectroscopy were used to characterize the nanoparticles. Both NEM-olive oil and Ag/NEM-olive oil nanoparticles showed a negative surface charge and small diameter. The major components of NEM-olive oil are dodecanoic acid, 2-penten-1-yl ester, 9-octadecenoic acid, and oleic acid. All tested nanoparticles exhibited anticancer activity against the CACO-2 cell line and Hep G2, and antimicrobial activities against E. faecalis, S. aureus, E. coli, and C. albicans. The present research suggested that olive oil NEM loaded with marine algae Ag-NPs can be a safe and economical anticancer, antimicrobial, and drug delivery.

Enhanced biosynthesis of coated silver nanoparticles using isolated bacteria from heavy metal soils and their photothermal-based antibacterial activity: integrating Response Surface Methodology (RSM) Hybrid Artificial Neural Network (ANN)-Genetic Algorithm (GA) strategies.

This study explores the biosynthesis of silver nanoparticles (AgNPs) using the Streptomyces tuirus S16 strain, presenting an eco-friendly alternative to mitigate the environmental and health risks of chemical synthesis methods. It focuses on optimizing medium culture conditions, understanding their physicochemical properties, and investigating their potential photothermal-based antibacterial application. The S16 strain was selected from soils contaminated with heavy metals to exploit its ability to produce diverse bioactive compounds. By employing the combination of Response Surface Methodology (RSM) and Artificial Neural Network (ANN)-Genetic Algorithm (GA) strategies, we optimized AgNPs synthesis, achieving an improvement of nearly 2.45 times the initial yield under specific conditions (Bennet's medium supplemented with glycerol [5g/L] and casamino-acid [3g/L] at 30°C for 72h). A detailed physicochemical characterization was conducted. Notably, the AgNPs were well dispersed, and a carbonaceous coating layer on their surface was confirmed using energy-dispersive X-ray spectroscopy. Furthermore, functional groups were identified using Fourier-transform infrared spectroscopy, which helped enhance the AgNPs' stability and biocompatibility. AgNPs also demonstrated efficient photothermal conversion under light irradiation (0.2 W/cm2), with temperatures increasing to 41.7°C, after 30min. In addition, treatment with light irradiation of E. coli K-12 model effectively reduced the concentration of AgNPs from 105 to 52.5µg/mL, thereby enhancing the efficacy of silver nanoparticles in contact with the E. coli K-12.