Novel Synthesis of Ultra-Small Silver Nanoparticles with High Antimicrobial Activity

2008 ◽  
Vol 47-50 ◽  
pp. 1080-1083 ◽  
Author(s):  
H.J. Lee ◽  
M.A. Do ◽  
E.J. Kim ◽  
J.H. Yeum ◽  
H.D. Ghim ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Antimicrobial Activity ◽  
Silver Nanoparticles ◽  
Particle Size Analysis ◽  
Wound Dressings ◽  
Size Analysis ◽  
High Antimicrobial Activity ◽  
Novel Synthesis ◽  
Transmission Electron

Ultra-small and well dispersed silver nanoparticles were prepared by mixing AgNO3 in PEI (polyethylenimine) solution. Particle size analysis and transmission electron microscopy confirmed that the average diameters of PEI/silver nanoparticles are 20-40 nm. The ultra-small silver nanoparticles had an antimicrobial activity in the aqueous solution at the concentration over 0.0105% by M.I.C test. Suggestively, the PEI/silver nanoparticles have potentials for development of wound dressings.

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

Molecules ◽  
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).

Preparation of Triangular Silver Nanoparticles Using Polyvinyl Pyrrolidone with Different Concentration

2013 ◽  
Vol 873 ◽  
pp. 206-210
Author(s):  
Kai Li ◽  
Rao Fu ◽  
Qing Ran Gao ◽  
Ai Wei Tang ◽  
Ying Feng Wang
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Silver Nanoparticles ◽  
Driving Force ◽  
Ostwald Ripening ◽  
Polyvinyl Pyrrolidone ◽  
Protective Agent ◽  
Ag Nps ◽  
Transmission Electron ◽  
Uv Visible

This paper continues our previous work on preparation of triangular silver nanoparticles. The method proceeds with reaction of silver nitrate with hydrazine hydrate in the presence of polyvinyl pyrrolidone in aqueous solution. Effects of the concentration of PVP on the morphologies of Ag NPs were systematically investigated. The obtained Ag NPs were characterized by transmission electron microscopy and UV-visible spectrophotometer. The results showed that, triangular Ag NPs with edge lengths in the range of 50-200 nm were obtained using PVP as protective agent with lower concentration. As the concentration of PVP increased, spherical Ag NPs with their sizes about 6.2 nm were prepared and triangular Ag NPs were not obtained. The formation mechanism of triangular Ag NPs has been studied. Ostwald ripening is the driving force on the conversion of spherical Ag NPs to triangular Ag NPs in the presence of PVP.

Preparation of Amorphous Nanosilica from Philippine Waste Rice Hull via Acid Precipitation Method

2016 ◽  
Vol 864 ◽  
pp. 112-116
Author(s):  
Rinlee Butch M. Cervera ◽  
Emie A. Salamangkit-Mirasol
Keyword(s):  
Electron Microscopy ◽  
Low Cost ◽  
Agricultural Waste ◽  
Acid Precipitation ◽  
Particle Size Analysis ◽  
Precipitation Method ◽  
Rice Hull ◽  
Size Analysis ◽  
Rice Hull Ash ◽  
Transmission Electron

Rice hull or rice husk (RH) is an agricultural waste obtained from milling rice grains. Since RH has no commercial value and is difficult to use in agriculture, its volume is often reduced through open field burning which is an environmental hazard. In this study, amorphous nanosilica from Philippine waste RH was prepared via acid precipitation method. The synthesized samples were fully characterized for its microstructural properties. X-ray diffraction pattern reveals that the structure of the prepared sample is amorphous in nature while Fourier transform infrared spectrum showed the different vibration bands of the synthesized sample. Scanning electron microscopy (SEM) and particle size analysis (PSA) confirmed the presence of agglomerated silica particles. On the other hand, transmission electron microscopy (TEM) revealed an amorphous sample with grain sizes of about 5 to 20 nanometer range and has about 95 % purity according to EDS analyses. The elemental mapping also suggests that leaching of rice hull ash effectively removed the metallic impurity such as potassium element in the material. Hence, amorphous nanosilica was successfully prepared via a low-cost acid precipitation method from Philippine waste rice hull.

scholarly journals Potential Decontamination of Drinking Water Pathogens through k-Carrageenan Integrated Green Bottle Fly Bio-Synthesized Silver Nanoparticles

Molecules ◽  
2020 ◽  
Vol 25 (8) ◽  
pp. 1936 ◽  
Author(s):  
M. A. Abu-Saied ◽  
Mohamed Elnouby ◽  
Tarek Taha ◽  
Muhammad El-shafeey ◽  
Ali G. Alshehri ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Antimicrobial Activity ◽  
Silver Nanoparticles ◽  
Drinking Water ◽  
Pathogenic Bacteria ◽  
Polymeric Nanoparticles ◽  
Wide Distribution ◽  
Spectrophotometric Analysis ◽  
Transmission Electron ◽  
Green Bottle

The wide distribution of infections-related pathogenic microbes is almost related to the contamination of food and/or drinking water. The current applied treatments face some limitations. In the current study, k-carrageenan polymer was used as supporting material for the proper/unreleased silver nanoparticles that showed strong antimicrobial activity against six pathogenic bacteria and yeast. The bio-extract of the pupa of green bottle fly was used as the main agent for the synthesis of silver nanoparticles. The qualitative investigation of biologically synthesized silver nanoparticles was determined using UV-Vis spectrophotometric analysis; however, the size of nanoparticles was in range of 30–100 nm, as confirmed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and particle size analyzer. The proper integration of silver nanoparticles into the polymeric substrate was also characterized through fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), SEM, and tensile strength. The antimicrobial activity of k-carrageenan/silver nanoparticles against Gram positive, Gram negative, and yeast pathogens was highly effective. These results indicate the probable exploitation of the polymeric/nanoparticles composite as an extra stage in water purification systems in homes or even at water treatment plants.

The Evaporative Decomposition of Solutions Method (Eds) for the Production of Ultrafine Y1Ba2Cu3O7 from Nitrate and Mixed Anion Precursor Solutions

1989 ◽  
Vol 169 ◽  
Author(s):  
Rollin E. Lakis ◽  
Sidney R. Butler
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Barium Carbonate ◽  
Hollow Spheres ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

AbstractY1Ba2Cu3O7 has been prepared by the evaporative decomposition of solutions method. Nitrate and mixed anion solutions were atomized and decomposed at temperatures ranging from 300°C to 950°C. The resulting materials have been characterized using x-ray powder diffraction, Thermal Gravimetric Analysis (TGA), particle size analysis, Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). The powder consists of 0.3 micron agglomerated hollow spheres with a primary particle size of 0.06 micron. TGA and x-ray diffraction indicate the presence of barium nitrate and barium carbonate due to incomplete decomposition and/or product contamination by the process environment.

Solvothermal synthesis of zirconia and yttria-stabilized zirconia nanocrystalline particles

2007 ◽  
Vol 22 (1) ◽  
pp. 46-55 ◽  
Author(s):  
Xin M. Wang ◽  
Ping Xiao
Keyword(s):  
Electron Microscopy ◽  
Nitrogen Adsorption ◽  
Particle Size Analysis ◽  
Zirconium Hydroxide ◽  
Yttria Stabilized Zirconia ◽  
Size Analysis ◽  
Stabilized Zirconia ◽  
Particle Properties ◽  
Transmission Electron ◽  
Nanocrystalline Particles

A solvothermal method was used to prepare zirconia and yttria-stabilized zirconia (YSZ) particles using zirconium hydroxide and yttrium hydroxide particles as precursors and ethanol or isopropanol as reaction media. The particle properties were characterized with x-ray diffractometry, scanning electron microscopy, transmission electron microscopy, thermal analysis, laser particle-size analysis, nitrogen adsorption (Brunauer–Emmett–Teller method) and Zeta potential analysis. Cubic/tetragonal ZrO2 and YSZ nanocrystals with crystallite size around 5 nm were obtained. The effect of different hydroxide precursors, attrition milling of hydroxide precursors, solvothermal processing conditions, and mineralizer was investigated and discussed by referring to the crystallization process of zirconium hydroxides.

scholarly journals Phytochemical Synthesis and Preliminary Characterization of Silver Nanoparticles Using Hesperidin

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Anish Stephen ◽  
Sankar Seethalakshmi
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Transmission Electron Microscopy ◽  
Silver Nanoparticles ◽  
Reaction Time ◽  
Silver Nanoparticle ◽  
Size Range ◽  
Transmission Electron ◽  
Vis Spectroscopy

This paper is the first of its kind for development of rapid and ecofriendly method for synthesis of silver nanoparticles from aqueous solution of silver nitrate using the flavonoid “hesperidin” and optimization of the methodology. There is formation of stable spherical silver nanoparticles in the size range of 20–40 nm. Optimization of methodology in terms of concentration of reactants and pH of the reaction mixture reduced the reaction time for silver nanoparticle formation to 2 mins. Silver nanoparticles (AgNPs) were characterized by UV-Vis spectroscopy and transmission electron microscopy (TEM). UV-vis spectroscopy derived spectrum demonstrated a peak of 430 nm which corresponds to the plasmon absorbance of silver nanoparticles. Transmission electron microscopy revealed spherical shaped silver nanoparticles in the size range of 20–40 nm.

Silver Nanoparticles Incorporated Electrospun Silk Fibers

2007 ◽  
Vol 7 (11) ◽  
pp. 3888-3891 ◽  
Author(s):  
Minsung Kang ◽  
Rira Jung ◽  
Hun-Sik Kim ◽  
Ji Ho Youk ◽  
Hyoung-Joon Jin
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Silver Nanoparticles ◽  
Silk Fibroin ◽  
Wound Dressings ◽  
Silk Fibers ◽  
Transmission Electron ◽  
Electrospun Membranes ◽  
Silk Fibroin Nanofibers ◽  
Fibroin Solution

We present a simple and mass-producible method of incorporating silver nanoparticles on the surface of electrospun silk non-woven membranes for the fabrication of antimicrobial wound dressings. Nanofibrous silk membranes with fiber diameters of 460±40 nm were electrospun from an aqueous Bombyx mori fibroin solution. The electrospun membranes incorporating silver nanoparticles were prepared by dipping the membranes in aqueous silver nitrate (AgNO3) solution (0.5 or 1.0 wt%) followed by photoreduction. Field emission scanning and transmission electron microscopy showed that silver nanoparticles were generated on the electrospun silk fibroin nanofibers as well as inside them. The interaction between the silver nanoparticles and amide groups in the silk fibroin molecules was characterized using X-rayphotoelectron spectroscopy.

scholarly journals Stachybotrys chartarum: A Novel Biological Agent for The Extracellular Synthesis of Silver Nanoparticles and Their Antimicrobial Activity

2015 ◽  
Vol 18 (2) ◽  
pp. 75 ◽  
Author(s):  
Abdel Ghany Tarek Mohamed
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Antimicrobial Activity ◽  
Silver Nanoparticles ◽  
Silver Nitrate ◽  
Stachybotrys Chartarum ◽  
Capping Agent ◽  
Extracellular Synthesis ◽  
Transmission Electron

Microbial assisted biosynthesis of nanoparticles is a rapidly progressing area of nanobiotechnology. Inthis paper Stachybotrys chartarum assisted extracellular synthesis of silver nanoparticles (AgNPs) is reportedwhen challenged with 1mM silver nitrate (AgNO3). The characterization of AgNPs was carried out visualobservation and UV-Vis spectrophotometry. Further analysis carried out by Fourier Transform InfraredSpectroscopy (FTIR), provides evidence for the presence of proteins as capping agent, which helps in increasingthe stability of the synthesized AgNPs. Transmission Electron Microscopy (TEM) investigations confi rmedthat AgNPs were formed. The synthesized silver nanoparticles were found in the range of 65-108 nm. Finally,the antimicrobial susceptibility of AgNPs synthesized was investigated which exhibited more potent activityagainst bacteria than fungi compared with using silver nitrate at concentration 1mM. Keywords: Antimicrobial activity, Stachybotrys chartarum, Silver nanoparticles

Acoustics and Transport Properties of PEG Blended with CuO Nanoparticles: A Novel Application to Heat Transfer

2018 ◽  
Vol 17 (06) ◽  
pp. 1850005 ◽  
Author(s):  
Susmita Kamila ◽  
V. R. Venu Gopal ◽  
B. M. Satish
Keyword(s):  
Heat Transfer ◽  
Electron Microscopy ◽  
Transport Properties ◽  
Colloidal Dispersion ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Heat Transfer Fluids ◽  
Transmission Electron ◽  
Particulate Size ◽  
Powder Samples

The present investigation reports the acoustics and transport properties of a series of colloidal dispersion of nanocopper oxide in polyethylene glycol (PEG-400). The data are presented for five different CuO nanofluids of varying concentration in PEG prepared by the ultrasonication technique. The synthesized powder samples were characterized for their sizes and arrangement by X-ray Diffraction analysis (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM), which shows the particulate size to be of nanoscale with elongated shape. Similarly, the size and stability of nanofluids were studied by zeta potential and particle size analysis. Besides, ultrasonic velocity, viscosity measurement show better dispersivity of nanoparticles and molecular environment of the nanofluids, whereas the enhanced thermal as well as electrical conductivities of nanofluids can make them suitable for use as heat transfer fluids.

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