In Vitro Antioxidant, Antitumor and Photocatalytic Activities of Silver Nanoparticles Synthesized Using Equisetum Species: A Green Approach

The ethanolic extracts of three Equisetum species (E. pratense Ehrh., E. sylvaticum L. and E. telmateia Ehrh.) were used to reduce silver ions to silver nanoparticles (AgNPs). The synthesized AgNPs were characterized using UV-Vis spectrophotometry, Fourier Transform Infrared Spectroscopy (FTIR), Energy Dispersive X-ray (EDX), Transmission Electron Microscopy (TEM) and Dynamic Light Scattering (DLS) measurements. FTIR data revealed the functional groups of biomolecules involved in AgNPs synthesis, such as O-H, C-H, C=O, C-O, and C-C. EDX spectroscopy was used to highlight the presence of silver, while DLS spectroscopy provided information on the mean diameter of AgNPs, that ranged from 74.4 to 314 nm. The negative Zeta potential values (−23.76 for Ep–AgNPs, −29.54 for Es–AgNPs and −20.72 for Et–AgNPs) indicate the stability of the obtained colloidal solution. The study also focused on establishing the photocatalytic activity of AgNPs, which is an important aspect in terms of removing organic dyes from the environment. The best photocatalytic activity was observed for AgNPs obtained from E. telmateia, which degraded malachite green in a proportion of 97.9%. The antioxidant action of the three AgNPs samples was highlighted comparatively through four tests, with the best overall antioxidant capacity being observed for AgNPs obtained using E. sylvaticum. Moreover, the biosynthesized AgNPs showed promising cytotoxic efficacy against cancerous cell line MG63, the AgNPs obtained from E. sylvaticum L. providing the best result, with a LD50 value around 1.5 mg/mL.

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A REVIEW: A GREEN APPROACH FOR THE SYNTHESIS OF SILVER NANOPARTICLES AND ITS ANTIBACTERIAL APPLICATIONS

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2018.v11i8.26767 ◽

2018 ◽

Vol 11 (8) ◽

pp. 74 ◽

Cited By ~ 1

Author(s):

Shyla Marjorie Haqq ◽

Amit Chattree

Keyword(s):

Silver Nanoparticles ◽

Antimicrobial Properties ◽

Nanoparticle Synthesis ◽

Silver Ions ◽

Multidrug Resistant ◽

X Ray Diffraction ◽

Green Approach ◽

Transmission Electron ◽

Uv Visible ◽

Silver Nanoparticle Synthesis

This review is based on the synthesis of silver nanoparticles (AgNPs) using a green approach which is biofabricated from various medicinal plants. AgNPs were prepared from the various parts of the plants such as the flowers, stems, leaves, and fruits. Various physiochemical characterizations were performed using the ultraviolet (UV)-visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy, transmission electron microscopy, and energy dispersive spectroscopy. AgNPs were also used to inhibit the growth of bacterial pathogens and were found to be effective against both the Gram-positive and Gram-negative bacteria. For the silver to have antimicrobial properties, it must be present in the ionized form. All the forms of silver-containing compounds with the observed antimicrobial properties are in one way or another source of silver ions. Although the antimicrobial properties of silver have been known, it is thought that the silver atoms bind to the thiol groups in enzymes and subsequently leads to the deactivation of enzymes. For the silver to have antimicrobial properties, it must be present in the ionized form. The study suggested that the action of the AgNPs on the microbial cells resulted into cell lysis and DNA damage. AgNPs have proved their candidature as a potential antibacterial against the multidrug-resistant microbes. The biological agents for synthesizing AgNPs cover compounds produced naturally in microbes and plants. Reaction parameters under which the AgNPs were being synthesized hold prominent impact on their size, shape, and application. Silver nanoparticle synthesis and their application are summarized and critically discussed in this review.

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An Inexpensive, Stable and Highly Efficient Photocatalyst for Degradation of Organic Dyes in Water: Core-Shell Montmorillonite-TiO2 Colloids

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.864-867.404 ◽

2013 ◽

Vol 864-867 ◽

pp. 404-407

Author(s):

Shi Zhao Kang ◽

Tan Wu ◽

Xiang Qing Li ◽

Yi Lun Zhou ◽

Jin Mu

Keyword(s):

Photocatalytic Activity ◽

Methyl Orange ◽

Organic Dyes ◽

Hydrothermal Process ◽

Core Shell ◽

X Ray Diffraction ◽

X Ray ◽

Highly Efficient ◽

Transmission Electron ◽

The Stability

Core-shell montmorillonite-TiO2 colloids were prepared in a hydrothermal process and characterized with transmission electron microscope, powder X-ray diffraction analysis, Brunauer-Emmett-Teller analysis and UV-vis spectra. Afterwards, their photocatalytic activity was investigated under UV irradiation using methyl orange as a model contaminant. In addition, the stability of the core-shell montmorillonite-TiO2 colloids was investigated by repeatedly performing methyl orange photocatalytic degradation experiments. The results indicate the as-prepared core-shell montmorillonite-TiO2 colloids are a highly efficient photocatalyst for the degradation of organic dyes in water. And this photocatalytic activity remains almost unchanged after eight successive cycles.

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Ecofriendly Synthesis of Silver Nanoparticles from Garden Rhubarb (Rheum rhabarbarum)

Journal of Nanotechnology ◽

10.1155/2016/4964752 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 14

Author(s):

Palem Ramasubba Reddy ◽

Shimoga D. Ganesh ◽

Nabanita Saha ◽

Oyunchimeg Zandraa ◽

Petr Sáha

Keyword(s):

Silver Nanoparticles ◽

Silver Ions ◽

X Ray Diffraction ◽

One Pot ◽

X Ray ◽

Plasmon Resonance Band ◽

Transmission Electron ◽

Resonance Band ◽

Crystalline Nature

Bioreduction of silver ions following one pot process is described to achieveRheum rhabarbarum(RR) based silver nanoparticles (SNPs) which is termed as “RR-SNPs.” The Ultraviolet–visible spectroscopy (UV–vis) confirms the characteristic surface plasmon resonance band for RR-SNPs in the range of 420–460 nm. The crystalline nature of SNPs was confirmed by X-ray diffraction (XRD) peaks at 38.2°, 45.6°, 64.2°, and 76.8°. Transmission electron microscopy (TEM) and scanning electronic microscopy (SEM) confirm the shape of synthesized SNPs. They are roughly spherical but uniformly distributed, and size varies from 60 to 80 nm. These biogenic SNPs show persistent zeta potential value of 34.8 mV even after 120 days and exhibit potent antibacterial activity in presence ofEscherichia coli(CCM 4517) andStaphylococcus aureus(CCM 4516). In addition, cytotoxicity of RR-SNPs againstin vitrohuman epithelial carcinoma (HeLa) cell line showed a dose-response activity. The lethal concentration (LC50) value was found to be 28.5 μg/mL for RR-SNPs in the presence of HeLa cells. These findings help us to evaluate their appropriate applications in the field of nanotechnology and nanomedicine.

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Biosynthesis of silver nanoparticles using Haloferax sp. NRS1: image analysis, characterization, in vitro thrombolysis and cytotoxicity

AMB Express ◽

10.1186/s13568-021-01235-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hend M. Tag ◽

Amna A. Saddiq ◽

Monagi Alkinani ◽

Nashwa Hagagy

Keyword(s):

Silver Nanoparticles ◽

Image Analysis ◽

Biological Activities ◽

Positive Control ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Vis Spectroscopy ◽

Negative Surface ◽

Biosynthesized Agnps

AbstractHaloferax sp strain NRS1 (MT967913) was isolated from a solar saltern on the southern coast of the Red Sea, Jeddah, Saudi Arabia. The present study was designed for estimate the potential capacity of the Haloferax sp strain NRS1 to synthesize (silver nanoparticles) AgNPs. Biological activities such as thrombolysis and cytotoxicity of biosynthesized AgNPs were evaluated. The characterization of silver nanoparticles biosynthesized by Haloferax sp (Hfx-AgNPs) was analyzed using UV–vis spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR). The dark brown color of the Hfx-AgNPs colloidal showed maximum absorbance at 458 nm. TEM image analysis revealed that the shape of the Hfx-AgNPs was spherical and a size range was 5.77- 73.14 nm. The XRD spectra showed a crystallographic plane of silver nanoparticles, with a crystalline size of 29.28 nm. The prominent FTIR peaks obtained at 3281, 1644 and 1250 cm− 1 identified the Functional groups involved in the reduction of silver ion reduction to AgNPs. Zeta potential results revealed a negative surface charge and stability of Hfx-AgNPs. Colloidal solution of Hfx-AgNPs with concentrations ranging from 3.125 to 100 μg/mL was used to determine its hemolytic activity. Less than 12.5 μg/mL of tested agent showed no hemolysis with high significant decrease compared with positive control, which confirms that Hfx-AgNPs are considered non-hemolytic (non-toxic) agents according to the ISO/TR 7405-1984(f) protocol. Thrombolysis activity of Hfx-AgNPs was observed in a concentration-dependent manner. Further, Hfx-AgNPs may be considered a promising lead compound for the pharmacological industry.

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Silver nanoparticles used to counter Monilinia fructicola fungicide-resistance and reduce fungicide environmental footprint

10.5194/egusphere-egu21-9285 ◽

2021 ◽

Author(s):

Constantinos Chrysikopoulos ◽

Anastasios A. Malandrakis ◽

Nektarios Kavroulakis ◽

Anthi Stefanarou

Keyword(s):

Silver Nanoparticles ◽

Control Plant ◽

Resistance Mutation ◽

Silver Ions ◽

Apple Fruit ◽

Ag Nps ◽

Gene Target ◽

Benzimidazole Fungicides

<div>The potential of silver nanoparticles (Ag-NPs) to control plant pathogen Moniliafructicola and to deter environmental contamination by reducing fungicide doses was evaluated in vitro and in vivo. &#160;Fungitoxicity screening of&#160;M. fructicola&#160;isolates resulted in the detection of 18 benzimidazole-resistant (BEN-R) isolates with reduced sensitivity to fungicides &#160;thiophanate methyl (TM)&#160; and carbendazim. All resistant isolates caried the E198A resistance mutation in their &#946;-tubulin gene, target site of the benzimidazole fungicides.&#160;Ag-NPs could effectively control both sensitive (BEN-S) and resistant isolates while the combination of Ag-NPs with TM significantly enhanced their fungitoxic effect both in vitro&#160;and in apple fruit tests. The positive correlation observed between Ag-NPs and TM+Ag-NPs treatments indicates a mixture-enhanced Ag-NPs activity/availability as a possible mechanism of synergy. No correlation between Ag-NPs&#160; and AgNO3&#160;could&#160; be found suggesting difference(s) in the fungitoxic mechanism of action between Nps and their bulk/ionic counterparts. Indications of the involvement of energy (ATP) metabolism in the mode of action of Ag-NPs were also evident by the synergy observed between Ag-NPs and the oxidative phosphorylation-uncoupler fluazinam (FM) against both BEN-R and BEN-S phenotypes. The role of silver ions release on the inhibitory action of Ag-NPs against the fungusis probably limited since the AgNPs/NaCl combination enhanced fungitoxicity, a fact that could not be justified by the expected binding of silver with chlorine ions. Concluding, Ag-NPs can be effectively used as a means of controlling both BEN-S and BEN-R M.&#160;fructicola&#160;isolates while&#160;their combination with conventional fungicides should aid anti-resistant strategies and reduce the environmental impact of synthetic fungicides by reducing effective doses to the control the pathogen.</div>

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Silver Nanoparticles Surface-Modified with Carbosilane Dendrons as Carriers of Anticancer siRNA

International Journal of Molecular Sciences ◽

10.3390/ijms21134647 ◽

2020 ◽

Vol 21 (13) ◽

pp. 4647 ◽

Cited By ~ 1

Author(s):

Elżbieta Pędziwiatr-Werbicka ◽

Michał Gorzkiewicz ◽

Katarzyna Horodecka ◽

Viktar Abashkin ◽

Barbara Klajnert-Maculewicz ◽

...

Keyword(s):

Gene Therapy ◽

Silver Nanoparticles ◽

Lymphocyte Proliferation ◽

Intracellular Transport ◽

Genetic Material ◽

Hydrodynamic Diameter ◽

Transmission Electron ◽

The Stability ◽

Surface Modified ◽

Sites Of Action

Gene therapy is a promising approach in cancer treatment; however, current methods have a number of limitations mainly due to the difficulty in delivering therapeutic nucleic acids to their sites of action. The application of non-viral carriers based on nanomaterials aims at protecting genetic material from degradation and enabling its effective intracellular transport. We proposed the use of silver nanoparticles (AgNPs) surface-modified with carbosilane dendrons as carriers of anticancer siRNA (siBcl-xl). Using gel electrophoresis, zeta potential and hydrodynamic diameter measurements, as well as transmission electron microscopy, we characterized AgNP:siRNA complexes and demonstrated the stability of nucleic acid in complexes in the presence of RNase. Hemolytic properties of free silver nanoparticles and complexes, their effect on lymphocyte proliferation and cytotoxic activity on HeLa cells were also examined. Confocal microscopy proved the effective cellular uptake of complexes, indicating the possible use of this type of silver nanoparticles as carriers of genetic material in gene therapy.

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SILVER NANOPARTICLES FROM MEDICINALLY IMPORTANT EUPHORBIA CYATHOPHORA EXTRACT: BIOSYNTHESIS, CHARACTERIZATION, AND ANTICANCER ACTIVITY.

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2018.v11i2.22216 ◽

2018 ◽

Vol 11 (2) ◽

pp. 154

Author(s):

Robert Lotha ◽

Aravind Sivasubramanian ◽

Meenakshi Sundaram Muthuraman

Keyword(s):

Electron Microscopy ◽

Silver Nanoparticles ◽

Cell Line ◽

Aqueous Extract ◽

Visible Spectroscopy ◽

X Ray ◽

Transmission Electron ◽

The Stability ◽

Ht 29 ◽

Scanning Electron

Objective: The present study was aimed at the biosynthesis of silver nanoparticles (AgNPs) using aqueous extract of Euphorbia cyathophora leavesand testing their anticancer potential using HT-29 cell line model.Methods: Green synthesis of silver nanoparticles was obtained with the aqueous extract of E. cyathophora. The synthesized nanoparticles wereconfirmed initially by ultraviolet-visible spectroscopy. Further, scanning electron microscopy, transmission electron microscopy, and X-Ray diffractionstudies also ensured the presence of silver nanoparticles. Zeta potential studies revealed the stability of the silver nanoparticles.Results: Antioxidant and anticancer studies of the nanoparticles against HT-29 cell line exhibited remarkable results.Conclusion: This ensures that the synthesized nanoparticles play an important role in medicinal biology.

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Bioinspired Synthesis of Acacia senegal Leaf Extract Functionalized Silver Nanoparticles and Its Antimicrobial Evaluation

Journal of Nanomaterials ◽

10.1155/2020/6474913 ◽

2020 ◽

Vol 2020 ◽

pp. 1-8

Author(s):

Edwina Olohirere Uzunuigbe ◽

Abidemi Paul Kappo ◽

Sixberth Mlowe ◽

Neerish Revaprasadu

Keyword(s):

Silver Nanoparticles ◽

Colour Change ◽

Silver Ions ◽

Antibacterial Activities ◽

Cubic Phase ◽

X Ray Diffraction ◽

Leaf Extracts ◽

Acacia Senegal ◽

Transmission Electron ◽

Antimicrobial Evaluation

Synthesizing nanoparticles with the less environmentally malignant approach using plant extract is of great interest; this is because most of the chemical approaches can be very costly, toxic, and time-consuming. Herein, we report the use of Acacia senegal leaf extracts to synthesize silver nanoparticles (AgNPs) using an environmentally greener approach. Silver ions were reduced using the bioactive components of the plant extracts with observable colour change from faint colourless to a brownish solution as indication of AgNP formation. The structural properties of the as-synthesized AgNPs were characterized using powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and UV-Vis absorption spectrum. Antimicrobial assessment of the as-synthesized AgNPs was explored on some strains of gram-positive and gram-negative bacteria. The obtained results indicate that the as-synthesized AgNPs are pure crystallite of cubic phase of AgNPs, fairly dispersed with a size range of 10–19 nm. The AgNPs were found to be small in size and exhibit significant antibacterial activities, suggesting that the as-synthesized AgNPs could be used in the pharmaceutical and food industries as bactericidal agents.

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Structural Stabilization of Human Transthyretin by Centella asiatica (L.) Urban Extract: Implications for TTR Amyloidosis

Biomolecules ◽

10.3390/biom9040128 ◽

2019 ◽

Vol 9 (4) ◽

pp. 128 ◽

Cited By ~ 5

Author(s):

Fredrick Nwude Eze ◽

Ladda Leelawatwattana ◽

Porntip Prapunpoj

Keyword(s):

Protein Misfolding ◽

Quaternary Structure ◽

Centella Asiatica ◽

Structural Stabilization ◽

Flight Mass Spectrometry ◽

Transmission Electron ◽

Small Molecule Ligands ◽

Therapeutic Development ◽

The Stability

Transthyretin is responsible for a series of highly progressive, degenerative, debilitating, and incurable protein misfolding disorders known as transthyretin (TTR) amyloidosis. Since dissociation of the homotetrameric protein to its monomers is crucial in its amyloidogenesis, stabilizing the native tetramer from dissociating using small-molecule ligands has proven a viable therapeutic strategy. The objective of this study was to determine the potential role of the medicinal herb Centella asiatica on human transthyretin (huTTR) amyloidogenesis. Thus, we investigated the stability of huTTR with or without a hydrophilic fraction of C. asiatica (CAB) against acid/urea-mediated denaturation. We also determined the influence of CAB on huTTR fibrillation using transmission electron microscopy. The potential binding interactions between CAB and huTTR was ascertained by nitroblue tetrazolium redox-cycling and 8-anilino-1-naphthalene sulfonic acid displacement assays. Additionally, the chemical profile of CAB was determined by liquid chromatography quadruple time-of-flight mass spectrometry (HPLC-QTOF-MS). Our results strongly suggest that CAB bound to and preserved the quaternary structure of huTTR in vitro. CAB also prevented transthyretin fibrillation, although aggregate formation was unmitigated. These effects could be attributable to the presence of phenolics and terpenoids in CAB. Our findings suggest that C. asiatica contains pharmaceutically relevant bioactive compounds which could be exploited for therapeutic development against TTR amyloidosis.

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Green Synthesis of Silver Nanoparticles using Salacca zalacca Extract as Reducing Agent and It’s Antibacterial Activity

Asian Journal of Chemistry ◽

10.14233/ajchem.2019.22238 ◽

2019 ◽

Vol 31 (12) ◽

pp. 2804-2810

Author(s):

Anti Kolonial Prodjosantoso ◽

Oktanio Sigit Prawoko ◽

Maximus Pranjoto Utomo ◽

Lis Permana Sari

Keyword(s):

Escherichia Coli ◽

Silver Nanoparticles ◽

Antibacterial Activity ◽

Staphylococcus Epidermidis ◽

Silver Ions ◽

Reduction Reaction ◽

Face Centered Cubic ◽

Gram Positive Bacteria ◽

Transmission Electron ◽

Face Centered

In this article, the synthesis of silver nanoparticles through a reduction reaction process using Salacca zalacca extract is reported. The AgNPs were characterized using X-ray diffraction, transmission electron microscopy, Fourier transform infrared and UV-visible spectrophotometry methods. The AgNPs antibacterial activity was determined against of Gram-positive bacteria (Staphylococcus epidermidis) and Gram-negative bacteria (Escherichia coli). The main functional groups contained in Salacca zalacca extract are carbonyl, hydroxyl and nitrile groups, which are believed to reduce the silver ions to metal. The surface plasmon resonance values of brownish red AgNPs are in the range of 410 nm to 460 nm. The structure of AgNPs is face centered cubic (FCC). The diameter of silver nanoparticles crystallite is 14.2 ± 2.6 nm. The AgNPs growth inhibition zones of Escherichia coli and Staphylococcus epidermidis are 9.6 mm and 9.2 mm, respectively.

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