Zirconium Carboxyaminophosphonate Nanosheets as Support for Ag Nanoparticles

A layered insoluble inorganic-organic solid, namely zirconium phosphate glycine-N,N-bismethylphosphonate, was used to prepare dispersions of nanosheets to support active metals such as metallic silver nanoparticles and zinc ions. Zr phosphate-phosphonate microcrystals were first exfoliated with methylamine to produce a stable colloidal dispersion and then the methylamine was removed by treatment with hydrochloric acid. The obtained colloidal dispersion of Zr phosphate-phosphonate nanosheets was used to immobilize silver or zinc cations, via ion exchange, with the acidic protons of the sheets. The layered matrix showed a great affinity for the metal cations up taking all the added cations. The treatment of the dispersions containing silver ions with ethanol yielded metal silver nanoparticles grafted on the surface of the layered host. The samples were characterized by X-ray powder diffraction, elemental analysis transmission electron microscopy, and selected samples were submitted to antimicrobial tests. The nanocomposites based on Ag nanoparticles showed good bactericidal properties against the bacterial reference strain Staphylococcus epidermidis (S. epidermidis).

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Biosynthesis of Silver Nanoparticles

MRS Proceedings ◽

10.1557/proc-774-o8.3 ◽

2003 ◽

Vol 774 ◽

Cited By ~ 1

Author(s):

Rajesh R. Naik ◽

Sarah J. Stringer ◽

Jay M. Johnson ◽

Morley O. Stone

Keyword(s):

Electron Microscopy ◽

Silver Nanoparticles ◽

Silver Ions ◽

Nucleation And Growth ◽

Inorganic Nanoparticles ◽

Inorganic Materials ◽

Synthetic Methods ◽

Metallic Silver ◽

Transmission Electron ◽

Binding Peptides

AbstractThe use of biomolecules in the creation of inorganic materials offers an alternative to conventional synthetic methods. Biomolecules are currently used to control nucleation and growth of inorganic nanoparticles. Here we demonstrate the formation of silver nanoparticles in the presence of silver-binding peptides. Examination of the silver nanoparticles by transmission electron microscopy revealed a variety of crystal morphologies such as hexagons, triangles and spheres. The peptides serve to reduce the silver ions in the aqueous solution to metallic silver as well as control crystal growth. The nucleation property of peptides can be used as tool for bottom-up fabrication.

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Effect of pH on the Green Synthesis of Silver Nanoparticles through Reduction with Pistiastratiotes L. Extract

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1131.223 ◽

2015 ◽

Vol 1131 ◽

pp. 223-226 ◽

Cited By ~ 1

Author(s):

Pranlekha Traiwatcharanon ◽

Kriengkri Timsorn ◽

Chatchawal Wongchoosuk

Keyword(s):

Silver Nanoparticles ◽

Green Synthesis ◽

Spherical Shape ◽

Silver Ions ◽

Basic Medium ◽

Metallic Silver ◽

Visible Spectroscopy ◽

Ag Nps ◽

Transmission Electron ◽

Effects Of Ph

In this work, we have presented the green synthesis of silver nanoparticles (Ag-NPs) using extracts of Pistiastratiotes L. as reducing agent. The silver nitrate (AgNO3) solutions were used as precursor. The experiments were performed under irradiation with a light that can help to increase the activation for reduction of silver ions (Ag+) to metallic silver (Ag0). The effects of pH on the nature of Ag-NPs have been systematically studied by using ultraviolet-visible spectroscopy (UV-Vis) and transmission electron microscopy (TEM). The results show that the synthesis of Ag-NPs in acidic medium gives smaller size than that in basic medium. A number of synthesized Ag-NPs increase with increasing the concentrations of acidic/basic medium. All synthesized Ag-NPs have spherical shape.

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Growth of Ag-Nanoparticles: Shape-Directing Role of Silver Ions and Stabilizer in Aqueous Solutions

JOURNAL OF ADVANCES IN CHEMISTRY ◽

10.24297/jac.v6i3.2642 ◽

2010 ◽

Vol 6 (3) ◽

pp. 1049-1058

Author(s):

Zoya Zaheer ◽

Rafiuddin Rafiuddin

Keyword(s):

Silver Nanoparticles ◽

Optical Properties ◽

Ag Nanoparticles ◽

Cetyltrimethylammonium Bromide ◽

Silver Ions ◽

Average Diameter ◽

Capping Agent ◽

Transmission Electron ◽

Uv Visible

Silver nanoparticles were synthesized using Tulsi leaves extract as reducing as well as a capping agent to reduce the steps and parameters involved in the synthesis. The morphology, stability and optical properties of Ag-nanoparticles depend on reactants and stabilizer, cetyltrimethylammonium bromide (CTAB) concentrations. The silver nanoparticles were characterized by UV-visible spectrophotometer, and transmission electron microscope (TEM). Spherical morphology of the silver nanoparticles with an average diameter of 25 nm. Morphology changed markedly from spherical aggregated to highly polydispersed in presence of CTAB.

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Silver Nanoparticles as a New Generation of Antimicrobial Prophylaxis

Journal of Siberian Federal University Biology ◽

10.17516/1997-1389-0301 ◽

2019 ◽

pp. 266-276 ◽

Cited By ~ 1

Author(s):

Ilnur T. Garipov ◽

Renat R. Khaydarov ◽

Olga U. Gapurova ◽

Rashid A. Khaydarov ◽

Firdaus M. Lutfi ◽

...

Keyword(s):

Silver Nanoparticles ◽

Cotton Fabric ◽

Ag Nanoparticles ◽

Antimicrobial Prophylaxis ◽

Silver Ions ◽

Antimicrobial Effect ◽

Water Soluble ◽

Metallic Silver ◽

Saprotrophic Fungi ◽

Biofilm Growth

Over the last 20 years, metallic silver in the form of Ag nanoparticles has made a remarkable comeback as an example of a nanomaterial for control of microorganisms. The purpose of our study was a) to quantitatively estimate the antimicrobial effect of silver nanoparticles compared with that of silver ions and b) to check the efficacy of nanosilver as an antimicrobial agent against a range of microbes on the surface of water-soluble paint, 100% cotton fabric, and fibrous chemisorbent. Minimum inhibitory concentration tests quantitatively showed that Ag nanoparticles were less efficient than Ag+ ions against representatives of gram-positive / gram-negative bacteria and cosmopolitan saprotrophic fungi. Antifungal/antibacterial effects against Aspergillus niger, Penicillium phoeniceum, and Staphylococcus aureus were confirmed for nanosilver concentrations of even 1 μg/cm2 on the surface of cotton fabric and 0.8 μg/cm2 in water-soluble paint. As the concentration of nanosilver in water-soluble paint/cotton fabric was increased to 7 μg/cm2, the growth of Bacillus subtilis and Escherichia coli was suppressed as well. Microbiological tests conducted over a period of 60 days showed that there was no biofilm growth on the surface of a silver nanoparticle-coated fiber sorbent during its everyday operation as a household water treatment filter. Thus, silver nanoparticles as an add-on to water-soluble paints, textile fabrics or fiber chemisorbents had a remarkable antibacterial/antifungal effect, although some of the Ag nanoparticles were agglomerated into larger colloidal clusters

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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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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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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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Optimization of biogenic synthesis of silver nanoparticles from flavonoid-rich Clinacanthus nutans leaf and stem aqueous extracts

Royal Society Open Science ◽

10.1098/rsos.200065 ◽

2020 ◽

Vol 7 (7) ◽

pp. 200065 ◽

Cited By ~ 1

Author(s):

Siti Nur Aishah Mat Yusuf ◽

Che Nurul Azieyan Che Mood ◽

Nor Hazwani Ahmad ◽

Doblin Sandai ◽

Chee Keong Lee ◽

...

Keyword(s):

Silver Nanoparticles ◽

Functional Groups ◽

Silver Ions ◽

Cost Effective ◽

Aqueous Extracts ◽

Tem Analysis ◽

Transmission Electron ◽

Vis Spectroscopy ◽

The Face ◽

Clinacanthus Nutans

Background : Silver nanoparticles (AgNPs) are widely used in food industries, biomedical, dentistry, catalysis, diagnostic biological probes and sensors. The use of plant extract for AgNPs synthesis eliminates the process of maintaining cell culture and the process could be scaled up under a non-aseptic environment. The purpose of this study is to determine the classes of phytochemicals, to biosynthesize and characterize the AgNPs using Clinacanthus nutans leaf and stem extracts. In this study, AgNPs were synthesized from the aqueous extracts of C. nutans leaves and stems through a non-toxic, cost-effective and eco-friendly method. Results : The formation of AgNPs was confirmed by UV-Vis spectroscopy, and the size of AgNP-L (leaf) and AgNP-S (stem) were 114.7 and 129.9 nm, respectively. Transmission electron microscopy (TEM) analysis showed spherical nanoparticles with AgNP-L and AgNP-S ranging from 10 to 300 nm and 10 to 180 nm, with average of 101.18 and 75.38 nm, respectively. The zeta potentials of AgNP-L and AgNP-S were recorded at −42.8 and −43.9 mV. X-ray diffraction analysis matched the face-centred cubic structure of silver and was capped with bioactive compounds. Fourier transform infrared spectrophotometer analysis revealed the presence of few functional groups of phenolic and flavonoid compounds. These functional groups act as reducing agents in AgNPs synthesis. Conclusion : These results showed that the biogenically synthesized nanoparticles reduced silver ions to silver nanoparticles in aqueous condition and the AgNPs formed were stable and less toxic.

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Synthesis and Characterization of Ag-PILC Through the Formation of Ag@Montmorillonite Nanocomposite

NANO ◽

10.1142/s1793292015500319 ◽

2015 ◽

Vol 10 (02) ◽

pp. 1550031 ◽

Cited By ~ 2

Author(s):

Feng Rao ◽

Shaoxian Song ◽

Alejandro Lopez-Valdivieso

Keyword(s):

Ag Nanoparticles ◽

Silver Ions ◽

Trisodium Citrate ◽

X Ray Diffraction ◽

Exchange Method ◽

Ph Values ◽

Transmission Electron ◽

Bet Method ◽

Novel Method

Ag pillared interlayered clays ( Ag -PILCs) were synthesized through a novel method, in which Ag nanoparticles were formed in montmorillonite interlayers. In this method, silver ions were first exchanged into montmorillonite interlayers, and then reduced into Ag nanoparticles by trisodium citrate at 100°C in aqueous solutions. The synthesized Ag @montmorillonite nanocomposite was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM), and its surface area was evaluated by using Brunauer–Emmet–Teller (BET) method. Compared to traditional PILCs synthesized through ion exchange method, the formed Ag -PILCs had better thermal stability and stronger structure because their pillars are nanoparticles. Furthermore, this method introduces a possibility to control the size of the pillars and thus the pore size of the PILCs, due to that the nanoparticle pillars can be modified on their forms and diameters in the synthesizing process. Also, it was found that the intercalating Ag nanoparticle pillars were formed at restricted pH values and silver ion concentrations.

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