Coating of Polyetheretherketone Films with Silver Nanoparticles by a Simple Chemical Reduction Method and Their Antibacterial Activity

The coating of polymeric substrate polyetheretherketone (PEEK) with silver nanoparticles (AgNPs) was carried out by a wet chemical route at room temperature. The coating process was developed from the Tollens reagent and D-glucose as reducing agent. The resulting composite exhibited antimicrobial activity. The PEEK films were coated with a single layer and two layers of silver nanoparticles in various concentrations. The crystallographic properties of the polymer and the silver nanoparticles were analyzed by X-ray diffraction (XRD). Fourier transform infrared spectra (FTIR) show the interaction between the silver nanoparticles with the polymeric substrate. Transmission electron microscope (TEM) images confirmed the obtaining of metallic nanoparticles with average sizes of 25 nm. It was possible to estimate the amount of silver deposited on PEEK with the help of thermogravimetric analysis. The morphology and shape of the AgNPs uniformly deposited on the PEEK films was ascertained by the techniques of scanning electron microscopy (SEM) and atomic force microscopy (AFM), evidencing the increase in the amount of silver by increasing the concentration of the metal precursor. Finally, the antibacterial activity of the films coated with Ag in Escherichia coli, Serratia marcescens and Bacillus licheniformis was evaluated, evidencing that the concentration of silver is crucial in the cellular replication of the bacteria.

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The Antimicrobial and Anti-Inflammatory Effects of Silver Nanoparticles Synthesised from Cotyledon orbiculata Aqueous Extract

Nanomaterials ◽

10.3390/nano11051343 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1343

Author(s):

Caroline Tyavambiza ◽

Abdulrahman Mohammed Elbagory ◽

Abram Madimabe Madiehe ◽

Mervin Meyer ◽

Samantha Meyer

Keyword(s):

Staphylococcus Aureus ◽

Silver Nanoparticles ◽

Metallic Nanoparticles ◽

Methicillin Resistance ◽

Antimicrobial Activities ◽

Transmission Electron ◽

Anti Inflammatory ◽

Anti Inflammation ◽

Important Medicinal Plant ◽

Pro Inflammatory Cytokines

Cotyledon orbiculata, commonly known as pig’s ear, is an important medicinal plant of South Africa. It is used in traditional medicine to treat many ailments, including skin eruptions, abscesses, inflammation, boils and acne. Many plants have been used to synthesize metallic nanoparticles, particularly silver nanoparticles (AgNPs). However, the synthesis of AgNPs from C. orbiculata has never been reported before. The aim of this study was to synthesize AgNPs using C. orbiculata and evaluate their antimicrobial and immunomodulatory properties. AgNPs were synthesized and characterized using Ultraviolet-Visible Spectroscopy (UV-Vis), Dynamic Light Scattering (DLS) and High-Resolution Transmission Electron Microscopy (HR-TEM). The antimicrobial activities of the nanoparticles against skin pathogens (Staphylococcus aureus, Staphylococcus epidermidis, Methicillin Resistance Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans) as well as their effects on cytokine production in macrophages (differentiated from THP-1 cells) were evaluated. The AgNPs from C. orbiculata exhibited antimicrobial activity, with the highest activity observed against P. aeruginosa (5 µg/mL). The AgNPs also showed anti-inflammatory activity by inhibiting the secretion of pro-inflammatory cytokines (TNF-alpha, IL-6 and IL-1 beta) in lipopolysaccharide-treated macrophages. This concludes that the AgNPs produced from C. orbiculata possess antimicrobial and anti-inflammation properties.

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Green Synthesized Silver Nanoparticles Immobilized on Activated Carbon Nanoparticles: Antibacterial Activity Enhancement Study and Its Application on Textiles Fabrics

Molecules ◽

10.3390/molecules26133790 ◽

2021 ◽

Vol 26 (13) ◽

pp. 3790

Author(s):

Pratama Jujur Wibawa ◽

Muhammad Nur ◽

Mukhammad Asy’ari ◽

Wijanarka Wijanarka ◽

Heru Susanto ◽

...

Keyword(s):

Silver Nanoparticles ◽

Antibacterial Activity ◽

Activated Carbon ◽

Aloe Vera ◽

Particle Size Analysis ◽

Size Analysis ◽

E Coli ◽

Transmission Electron ◽

Average Size ◽

Green Synthesized Silver Nanoparticles

This research aimed to enhance the antibacterial activity of silver nanoparticles (AgNPs) synthesized from silver nitrate (AgNO3) using aloe vera extract. It was performed by means of incorporating AgNPs on an activated carbon nanoparticle (ACNPs) under ultrasonic agitation (40 kHz, 2 × 50 watt) for 30 min in an aqueous colloidal medium. The successful AgNPs synthesis was clarified with both Ultraviolet-Visible (UV-Vis) and Fourier Transform Infrared (FTIR) spectrophotometers. The successful AgNPs–ACNPs incorporation and its particle size analysis was performed using Transmission Electron Microscope (TEM). The brown color suspension generation and UV-Vis’s spectra maximum wavelength at around 480 nm confirmed the existence of AgNPs. The particle sizes of the produced AgNPs were about 5 to 10 nm in the majority number, which collectively surrounded the aloe vera extract secondary metabolites formed core-shell like nanostructure of 8.20 ± 2.05 nm in average size, while ACNPs themselves were about 20.10 ± 1.52 nm in average size formed particles cluster, and 48.00 ± 8.37 nm in average size as stacking of other particles. The antibacterial activity of the synthesized AgNPs and AgNPs-immobilized ACNPs was 57.58% and 63.64%, respectively (for E. coli); 61.25%, and 93.49%, respectively (for S. aureus). In addition, when the AgNPs-immobilized ACNPs material was coated on the cotton and polyester fabrics, the antibacterial activity of the materials changed, becoming 19.23% (cotton; E. coli), 31.73% (polyester; E. coli), 13.36% (cotton; S. aureus), 21.15% (polyester; S. aureus).

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Size Control of Synthesized Silver Nanoparticles by Simultaneous Chemical Reduction and Laser Fragmentation in Origanum majorana Extract: Antibacterial Application

Materials ◽

10.3390/ma14092326 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2326

Author(s):

Entesar Ali Ganash ◽

Reem Mohammad Altuwirqi

Keyword(s):

Silver Nanoparticles ◽

Irradiation Time ◽

Chemical Reduction ◽

Size Control ◽

Reduction Process ◽

Laser Wavelength ◽

X Ray Diffraction ◽

Ag Nps ◽

Transmission Electron ◽

Origanum Majorana

In this work, silver nanoparticles (Ag NPs) were synthesized using a chemical reduction approach and a pulsed laser fragmentation in liquid (PLFL) technique, simultaneously. A laser wavelength of 532 nm was focused on the as produced Ag NPs, suspended in an Origanum majorana extract solution, with the aim of controlling their size. The effect of liquid medium concentration and irradiation time on the properties of the fabricated NPs was studied. While the X-ray diffraction (XRD) pattern confirmed the existence of Ag NPs, the UV–Vis spectrophotometry showed a significant absorption peak at about 420 nm, which is attributed to the characteristic surface plasmon resonance (SPR) peak of the obtained Ag NPs. By increasing the irradiation time and the Origanum majora extract concentration, the SPR peak shifted toward a shorter wavelength. This shift indicates a reduction in the NPs’ size. The effect of PLFL on size reduction was clearly revealed from the transmission electron microscopy images. The PLFL technique, depending on experimental parameters, reduced the size of the obtained Ag NPs to less than 10 nm. The mean zeta potential of the fabricated Ag NPs was found to be greater than −30 mV, signifying their stability. The Ag NPs were also found to effectively inhibit bacterial activity. The PLFL technique has proved to be a powerful method for controlling the size of NPs when it is simultaneously associated with a chemical reduction process.

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Antibacterial Activity of Silver Nanoparticles Synthesized by Bark Extract of Syzygium cumini

Journal of Nanoparticles ◽

10.1155/2013/431218 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 68

Author(s):

Ram Prasad ◽

Vyshnava Satyanarayana Swamy

Keyword(s):

Silver Nanoparticles ◽

Antibacterial Activity ◽

Cost Effective ◽

Diffusion Method ◽

Bark Extract ◽

Force Microscopy ◽

Atomic Force ◽

Cost Effective Method ◽

Uv Visible ◽

Major Attention

The unique property of the silver nanoparticles having the antimicrobial activity drags the major attention towards the present nanotechnology. The environmentally nontoxic, ecofriendly, and cost-effective method that has been developed for the synthesis of silver nanoparticles using plant extracts creates the major research interest in the field of nanobiotechnology. The synthesized silver nanoparticles have been characterized by the UV-visible spectroscopy, atomic force microscopy (AFM), and scanning electron microscopy (SEM). Further, the antibacterial activity of silver nanoparticles was evaluated by well diffusion method, and it was found that the biogenic silver nanoparticles have antibacterial activity against Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 29213), Pseudomonas aeruginosa (ATCC 27853), Azotobacter chroococcum WR 9, and Bacillus licheniformis (MTCC 9555).

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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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Bactericidal Silver Nanoparticles by Atmospheric Pressure Solution Plasma Processing

Nanomaterials ◽

10.3390/nano10050874 ◽

2020 ◽

Vol 10 (5) ◽

pp. 874 ◽

Cited By ~ 3

Author(s):

Janith Weerasinghe ◽

Wenshao Li ◽

Rusen Zhou ◽

Renwu Zhou ◽

Alexander Gissibl ◽

...

Keyword(s):

Silver Nanoparticles ◽

Atmospheric Pressure ◽

Chemical Reduction ◽

Cost Effective ◽

Pressure Solution ◽

Gram Negative Bacteria ◽

Promising Alternative ◽

Gram Negative ◽

Transmission Electron ◽

Solution Plasma Processing

Silver nanoparticles have applications in plasmonics, medicine, catalysis and electronics. We report a simple, cost-effective, facile and reproducible technique to synthesise silver nanoparticles via plasma-induced non-equilibrium liquid chemistry with the absence of a chemical reducing agent. Silver nanoparticles with tuneable sizes from 5.4 to 17.8 nm are synthesised and characterised using Transmission Electron Microscopy (TEM) and other analytic techniques. A mechanism for silver nanoparticle formation is also proposed. The antibacterial activity of the silver nanoparticles was investigated with gram-positive and gram-negative bacteria. The inhibition of both bacteria types was observed. This is a promising alternative method for the instant synthesis of silver nanoparticles, instead of the conventional chemical reduction route, for numerous applications.

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Properties of Silver Nanoparticles Prepared by the Electric Spark Dispersion Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.872.74 ◽

2013 ◽

Vol 872 ◽

pp. 74-78 ◽

Cited By ~ 3

Author(s):

S.P. Zhuravkov ◽

Evgeny Plotnikov ◽

Dmitry Martemiyanov ◽

Nikolay A. Yavorovsky ◽

Ulrich Hasse ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Silver Nanoparticles ◽

Structural Characteristics ◽

Silver Particles ◽

Dispersion Method ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Light Scattering Spectroscopy

The morphological and structural characteristics of nanoscale silver particles obtained by the method of electric spark dispersion of metal granules in the liquid aprotic medium were obtained using atomic force microscopy, transmission electron microscopy, and dynamic light scattering spectroscopy. The specific surface, morphology, structure and the distribution by size of the particles are presented.

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TWO-DIMENSIONAL PATTERNED NANOCRYSTALLINE Si ARRAY PREPARED BY LASER INTERFERENCE CRYSTALLIZATION OF ULTRA-THIN AMORPHOUS Si:H SINGLE-LAYER

International Journal of Nanoscience ◽

10.1142/s0219581x02000747 ◽

2002 ◽

Vol 01 (05n06) ◽

pp. 603-609

Author(s):

XINFAN HUANG ◽

XIAOWEI WANG ◽

FENG QIAO ◽

LEYI ZHU ◽

WEI LI ◽

...

Keyword(s):

Electron Microscopy ◽

Crystalline Silicon ◽

Single Layer ◽

Two Dimensional ◽

Laser Interference ◽

Raman Scattering Spectroscopy ◽

Force Microscopy ◽

Transmission Electron ◽

Device Applications ◽

Si Films

We employ the method of phase-modulated KrF excimer pulsed laser interference crystallization to fabricate nanometer-sized crystalline silicon with two-dimensional patterned distribution within the ultra-thin amouphous Si:H single-layer. The local phase transition occurs in ultra-thin a-Si:H film after laser interference crystallization under proper energy density. The results of atomic force microscopy, Raman scattering spectroscopy, cross-section transmission electron microscopy and scanning electron microscopy demonstrate that Si nanocrystallites are formed within the initial a-Si:H single-layer, selectively located in the discal regions with the diameter of 250 nm and patterned with the same 2D periodicity of 2.0 μm as the phase-shifting grating. The results demonstrate that the present method can be used to fabricate patterned nc-Si films for device applications.

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Silver Nanoparticles - Graphene Oxide Nanocomposite for Antibacterial Purpose

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.364.439 ◽

2011 ◽

Vol 364 ◽

pp. 439-443 ◽

Cited By ~ 5

Author(s):

Soon Wei Chook ◽

Chin Hua Chia ◽

Zakaria Sarani ◽

Mohd Khan Ayob ◽

Kah Leong Chee ◽

...

Keyword(s):

Silver Nanoparticles ◽

Graphene Oxide ◽

Metallic Nanoparticles ◽

Biomedical Applications ◽

Food Packaging ◽

Single Layer ◽

In Situ Synthesis ◽

Graphene Oxide Sheets

Graphene oxide (GO) sheets, a single layer of carbon atoms which can be served as substrates for fabricating metallic nanoparticles-GO nanocomposites. In this study, the nanocomposite of silver nanoparticles and graphene oxide were produced via in-situ synthesis and with the addition of chitosan to investigate the formation of silver nanoparticles on the graphene oxide sheets. XRD and UV-Vis studies confirmed the formation of silver nanoparticles on GO sheets, while TEM and FESEM images presented the loading of silver nanoparticles on the GO sheets. The degree of loading and distribution of the silver nanoparticles on the graphene oxide were depend on the method during the formation of silver nanoparticles. The nanocomposites can be potentially used in food packaging and biomedical applications.

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Green Synthesis Concept of Nanoparticles From Environmental Bacteria and Their Effects on Pathogenic Bacteria

Iraqi Journal of Science ◽

10.24996/ijs.2020.61.6.6 ◽

2020 ◽

pp. 1289-1297

Author(s):

Ghada Mohammed Saleh

Keyword(s):

Silver Nanoparticles ◽

Antibacterial Activity ◽

Soil Bacteria ◽

Pathogenic Bacteria ◽

Pseudomonas Sp ◽

Good Source ◽

Force Microscopy ◽

Atomic Force ◽

Environmental Bacteria ◽

Inhibition Zones

Soil bacteria play an interesting role in the reduction of Ag+ ions and the formation of silver nanoparticles (AgNPs), which may be a good source for nanoparticles and play a major role in nanotechnology applications. The concept of this project was to study the effects of these environmentally produced nanoparticles on the growth of some pathogenic bacteria. The environmental bacteria were isolated from soil, purified on broth cultures, and centrifuged, while the supernatant was extracted to detect its ability to convert silver nitrate to nanoparticles. The AgNPs was detected by Atomic Force Microscopy (AFM), while Granularity Cumulating Distribution (GCD) was employed to estimate the AgNPs sizes. The results showed the synthesis of AgNPs with sizes of 63.50nm and 45.81nm from the extracts of environmental Pseudomonas sp. and Enterobacter, respectively. The synthesized AgNPs from the extracts of all environmental bacteria showed antibacterial activity against some pathogenic bacteria (Gram positive and Negative) with variable inhibition zones. In conclusion, environmental bacteria can be a cheap source of nanoparticles.

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