Ag Nanoparticles Adsorption on Diatom-Montmorillonite Clays

2013 ◽  
Vol 755 ◽  
pp. 91-96
Author(s):  
A. Ruíz-Baltazar ◽  
R. Esparza ◽  
R. Pérez ◽  
G. Rosas
Keyword(s):  
Silver Nanoparticles ◽  
Porous Material ◽  
Ag Nanoparticles ◽  
Diatomaceous Earth ◽  
Chemical Reduction ◽  
Nitrate Solution ◽  
Silver Nitrate Solution ◽  
X Ray Diffraction ◽  
Montmorillonite Clays ◽  
Complementary Techniques

In this work, a spectroscopic and structural characterization of diatomaceous earth-montmorillonite clays after impregnated with silver nanoparticles were carried out. The silver nanoparticles were synthesized by chemical reduction with sodium borohydride starting from silver nitrate solution. The obtained nanoparticles were stabilized with polyvinyl-pyrrolidone as a surface agent. In order to perform the homogeneous nucleation process, Ag nanoparticles solutions at concentrations of 1, 2 and 4 parts per million were magnetically mixed in the porous material. Additionally, we assessed the porous material adsorption ability of silver by atomic absorption spectroscopy. The quantity of Ag nanoparticles adsorbed by the diatomaceous earth and the adsorption rate as function of the concentration of Ag nanoparticles were established. Other complementary techniques such as X-ray diffraction, infrared spectroscopy and transmission and scanning electron microscopy were used.

scholarly journals Antimicrobial Bacterial Cellulose-Silver Nanoparticles Composite Membranes

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Hernane S. Barud ◽  
Thaís Regiani ◽  
Rodrigo F. C. Marques ◽  
Wilton R. Lustri ◽  
Younes Messaddeq ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Silver Nanoparticles ◽  
Bacterial Cellulose ◽  
Nitrate Solution ◽  
Composite Membranes ◽  
Silver Nitrate Solution ◽  
Complexing Agent ◽  
X Ray Diffraction ◽  
Gram Positive Bacteria ◽  
Transmission Electron

Antimicrobial bacterial cellulose-silver nanoparticles composite membranes have been obtained by“in situ”preparation of Ag nanoparticles from hydrolytic decomposition of silver nitrate solution using triethanolamine as reducing and complexing agent. The formation of silver nanoparticles was evidenced by the X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and absorption in the UV-Visible (350 nm to 600 nm). Thermal and mechanical properties together with swelling behavior for water were considered. TEA concentration was observed to be important in order to obtain only Ag particles and not a mixture of silver oxides. It was also observed to control particle size and amount of silver contents in bacterial cellulose. The composite membranes exhibited strong antimicrobial activity against Gram-negative and Gram-positive bacteria.

A simple route for manufacturing highly dispersed silver nanoparticles

2007 ◽  
Vol 22 (9) ◽  
pp. 2488-2496 ◽  
Author(s):  
Daniel Andreescu ◽  
Christopher Eastman ◽  
Krishna Balantrapu ◽  
Dan V. Goia
Keyword(s):  
Silver Nanoparticles ◽  
Silver Nitrate ◽  
Ag Nanoparticles ◽  
Nitrate Solution ◽  
Reduction Rate ◽  
Silver Nitrate Solution ◽  
Metallic Phase ◽  
Simple Route ◽  
Dispersing Agent ◽  
Highly Dispersed

Highly dispersed uniform silver nanoparticles were prepared by reducing silver diamine ions [Ag(NH3)2]+ with D-glucose in the presence of a stabilizing agent. Along with the nature of the dispersing agent, the pH and the temperature of the reaction had the most pronounced effect on the reduction rate, the nucleation of the metallic phase, and ultimately the size and dispersion of the resulting particles. Through suitable manipulations of these parameters, it was possible to prepare uniform Ag nanoparticles ranging in size from 30 to 120 nm. A rapid and complete reduction of the silver species was possible only at elevated pH and temperatures above 50 °C. The reduction of silver diamine ions in these conditions caused the complete cleavage of the C–C bond, resulting in the release of 12 electrons per molecule of D-glucose. It was also found that the addition of ammonia to an already acidified silver nitrate solution leads to the formation of a much more stable and safe-to-handle diamine complex.

scholarly journals Sintesis dan karakterisai kitosan dari limbah cangkang udang sebagai stabilizer terhadap Ag nanopartikel

2019 ◽  
Vol 4 (2) ◽  
pp. 86
Author(s):  
Astuti Amin ◽  
Nur Khairi ◽  
Eko Allo
Keyword(s):  
Silver Nanoparticles ◽  
Chemical Reduction ◽  
Nitrate Solution ◽  
Average Particle Size ◽  
Silver Nitrate Solution ◽  
Raw Material ◽  
Average Particle ◽  
Synthesize Silver Nanoparticles ◽  
Shrimp Shell ◽  
Shell Powder

The research of manufacturing chitosan from shrimp shell waste , and their use as a stabilizer in the manufacture of silver nanoparticles has been done. The aim of the research was to synthesize silver nanoparticles using chitosan as a stabilizer by chemical reduction method and determine the effect of chitosan concentration on the stability of Ag nanoparticles. In this study, the raw material used is shrimp shell powder and then processed in several stages, eliminating proteins, demineralization, and deacetylation. Chitosan obtained is 16.4 % of shrimp shell powder, with a degree of deacetylation of 85 %. Chitosan is used to synthesize silver nanoparticles as a reducing agent of silver ions in silver nitrate solution and is expected to be stabilizer. Sample containing 45 mg of chitosan and 1000 ppm AgNO3 has 421,60 nm of maximum wavelength, and the average particle size is 154.07 nm.

scholarly journals Evaluation of the Cytotoxic Activity of Biosynthesized Silver Nanoparticles Using Berberis vulgaris Leaf Extract

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Akbar Safipour Afshar ◽  
Fatemeh Saeid Nematpour
Keyword(s):  
Silver Nanoparticles ◽  
Cytotoxic Activity ◽  
Leaf Extract ◽  
Nitrate Solution ◽  
Silver Nitrate Solution ◽  
X Ray Diffraction ◽  
Berberis Vulgaris ◽  
Transmission Electron ◽  
Cancerous Cells ◽  
Mcf 7

Background: Recently, due to the numerous applications of silver nanoparticles (AgNPs) in industry, various routes to synthesize them have been developed. Objectives: The current study was aimed at synthesizing silver nanoparticles by the leaf extract of Berberis vulgaris and evaluating the cytotoxic effects on human breast cancer MCF-7 cell line. Methods: The leaf extract of Berberis vulgaris and silver nitrate solution were used to synthesize silver nanoparticles. Ultraviolet (UV)-visible, Fourier-transform infrared, and X-ray diffraction analysis spectroscopy and transmission electron microscopy methods were used to characterize and confirm the nanoparticles’ synthesis. The cytotoxic activity of synthesized nanoparticles (0, 5,10, 20, 40 µg/mL) was also studied by MTT assay. Results: The results showed that Ag nanoparticles were polydisperse and spherical in shape and had a size of about 19.9 nm. Silver nanoparticles reduced the growth of cancerous cells based on time and concentration. The IC50 for MCF-7 cells at 48 hours was 20.27 µg/mL. Conclusions: The findings showed that synthesized nanoparticles have an appropriate cytotoxic effect on cancer cells. This impact may be due to the production of free radicals through the release of Ag ions.

scholarly journals Investigating the Possibility of Green Synthesis of Silver Nanoparticles Using Vaccinium arctostaphlyos Extract and Evaluating Its Antibacterial Properties

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Sedighe Khodadadi ◽  
Nafiseh Mahdinezhad ◽  
Bahman Fazeli-Nasab ◽  
Mohammad Javad Heidari ◽  
Baratali Fakheri ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Silver Nanoparticles ◽  
Ftir Spectroscopy ◽  
Aqueous Extract ◽  
Nitrate Solution ◽  
Antibacterial Properties ◽  
Silver Nitrate Solution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vis Spectroscopy

Objective. Vaccinium genus plants have medicinal value, of which Vaccinium arctostaphylos (Caucasian whortleberry or Qare-Qat in the local language) is the only available species in Iran. Public tendency to use herbal remedies and natural products such as synthesized nanoparticles is increasing due to the proof of the destructive side effects of chemical drugs. Nanosilver products have been effective against more than 650 microbe types. This study was aimed at assessing the possibility of green synthesis of silver nanoparticles using Vaccinium arctostaphylos aqueous extract and at evaluating its antibacterial properties, as well. Materials and Methods. In order to synthesize silver nanoparticles, different volumes of Vaccinium arctostaphylos aqueous extract (3, 5, 10, 15, and 30 ml) were assessed with different silver nitrate solution concentrations (0.5, 1, 3, 5, and 10 mM) and different reaction time durations (1, 3, 5, 10, and 20 minutes) at room temperature using a rotary shaker with a speed of 150 rpm. Ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction analysis (XRD), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) were carried out. The antibacterial activity of the aqueous extract and the synthesized nanoparticles was evaluated, as well. Results. Silver nanoparticle formation process was confirmed with XRD analysis, transmission electron microscopy (TEM), and FTIR spectroscopy. The UV-Vis spectroscopy of silver colloidal nanoparticles showed a surface plasmon resonance peak at 443 nm under optimal conditions (3 ml aqueous extract volume, 1 mM silver nitrate solution concentration, and 3 min reaction time under sunlight exposure). The reduction of silver ions to silver nanoparticles in solution was confirmed, as well. Based on X-ray diffraction analysis, the size of silver nanoparticles was in the range of 7-16 nm. TEM images showed an even distribution of silver nanoparticles, with a spherical shape. FTIR spectroscopy demonstrated the presence of different functional groups of oxygenated compounds such as carboxyl, hydroxyl, and nitrogenous groups. The antibacterial properties of the synthesized nanoparticles were confirmed. Conclusion. The synthesized nanoparticles showed more antibacterial properties against gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) than gram-negative ones (Escherichia coli and Salmonella enteritidis).

scholarly journals Comparative Antibacterial Study of Silver Nanoparticles Doped Activated Carbon Prepared by Different Methods

2020 ◽  
Vol 15 (1) ◽  
pp. 187-194
Author(s):  
Pragya Pandey ◽  
Bivek Karki ◽  
Binod Lekhak ◽  
Agni R. Koirala ◽  
R. K. Sharma ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Activated Carbon ◽  
Nitrate Solution ◽  
Analytical Techniques ◽  
Silver Nitrate Solution ◽  
Carbon Powder ◽  
X Ray Diffraction ◽  
Toxic Heavy Metals ◽  
Antibacterial Study ◽  
X Ray

 Activated carbon is greatly used to adsorb toxic heavy metals from water bodies. Simultaneous removal of such pollutants and pathogenic impurities is essential for safe drinking water. In this study, silver nanoparticles (NPs) doped activated carbon (AC) composite was fabricated via hydrothermal technique and green synthesis technique using commercial activated carbon powder and silver nitrate solution. Several analytical techniques, including scanning electron microscopy (SEM), energy dispersive x-ray (EDX), X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) confirmed the formation of silver nanoparticles on the surface and pores of AC. The prepared composite materials were accessed for their anti-bacterial property using Escherichia coli and Staphylococcus aureus and found that such materials have good antibacterial activity which shows that as fabricated composite can be used potentially for water treatment.

scholarly journals Protocol optimization for a fast, simple and economical chemical reduction synthesis of antimicrobial silver nanoparticles in non-specialized facilities

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Roberto Vazquez-Muñoz ◽  
M. Josefina Arellano-Jimenez ◽  
Fernando D. Lopez ◽  
Jose L. Lopez-Ribot
Keyword(s):  
Antimicrobial Activity ◽  
Silver Nanoparticles ◽  
Chemical Reduction ◽  
Nitrate Solution ◽  
Synthesis Method ◽  
Reduction Process ◽  
Cost Effective ◽  
Silver Nitrate Solution ◽  
Synthesis Time ◽  
Average Size

Abstract Objective Silver nanoparticles (AgNPs) can be difficult or expensive to obtain or synthesize for laboratories in resource-limited facilities. The purpose of this work was to optimize a synthesis method for a fast, facile, and cost-effective synthesis of AgNPs with antimicrobial activity, which can be readily implemented in non-specialized facilities and laboratories. Results The optimized method uses a rather simple and rapid chemical reduction process that involves the addition of a polyvinylpyrrolidone solution to a warmed silver nitrate solution under constant vigorous stirring, immediately followed by the addition of sodium borohydride. The total synthesis time is less than 15 min. The obtained AgNPs exhibit an aspect ratio close to 1, with an average size of 6.18 ± 5 nm. AgNPs displayed potent antimicrobial activity, with Minimal Inhibitory Concentration values of ≤ 4 µg mL−1 for Staphylococcus aureus and ≤ 2 µg mL−1 for Candida albicans. The resulting method is robust and highly reproducible, as demonstrated by the characterization of AgNPs from different rounds of syntheses and their antimicrobial activity.

scholarly journals A fast and simple protocol for synthesizing effective antimicrobial silver nanoparticles in non-specialized facilities

2019 ◽  
Author(s):  
Roberto Vazquez-Munoz ◽  
M. Josefina Arellano-Jimenez ◽  
Jose L. Lopez-Ribot
Keyword(s):  
Silver Nanoparticles ◽  
Metallic Nanoparticles ◽  
Chemical Reduction ◽  
Nitrate Solution ◽  
Synthesis Method ◽  
Antimicrobial Properties ◽  
Reduction Process ◽  
Cost Effective ◽  
Silver Nitrate Solution ◽  
Average Size

Abstract Objective Silver nanoparticles (AgNPs) can be difficult or expensive to obtain or synthesize for laboratories in resource-limited facilities. The purpose of this work was to create a fast, facile, and cost-effective method for synthesizing AgNPs with potent antimicrobial properties, that can be readily implemented in non-specialized laboratories.Results Our developed method uses a rather simple and rapid chemical reduction process that involves the addition of a polyvinylpyrrolidone solution to a warmed silver nitrate solution under constant vigorous stirring, immediately followed by the addition of sodium borohydride with constant stirring for an additional 15 minutes. AgNPs had an aspect ratio close to 1, with an average size of 6.18 ± 5 nm. AgNPs displayed potent antimicrobial activity, with Minimal Inhibitory Concentration values of 3 µg mL-1 and 1.5 µg mL-1 for Staphylococcus aureus and Candida albicans respectively.Keywords : Silver nanoparticles, nanoantibiotics, synthesis method, AgNPs, metallic nanoparticles

scholarly journals Synthesis of silver nanoparticles from electronic scrap by chemical reduction

2021 ◽  
Author(s):  
Abolhassan Najafi ◽  
Mahdi Khoeini ◽  
Gholamreza Khalaj ◽  
Amirhossein Sahebgharan
Keyword(s):  
Silver Nanoparticles ◽  
Silver Nitrate ◽  
Chemical Reduction ◽  
Electronic Waste ◽  
Nitrate Solution ◽  
Silver Nitrate Solution ◽  
Main Peak ◽  
Fcc Structure ◽  
Uniform Particle Size

Abstract In the present research, the use of electronic waste in the synthesis of silver nanoparticles was investigated. For this purpose, electronic scraps were used as a consumable part to synthesize silver nanoparticles. The results revealed that by optimizing the time and temperature of the dissolution process using nitric acid solution up to 90%, silver can be extracted from these parts. The temperature of 60°C and the duration of one hour were determined as the optimum conditions for this phase. Afterward, the synthesis of silver nanoparticles was checked using silver nitrate solution. The results indicated that the concentration of initial silver nitrate had a significant impact on the quality of the final product so that the best conditions for the synthesis of silver nanoparticles with suitable properties were provided at 1 molar concentration. Phase studies indicated that the main phase of the synthesized silver particles had an FCC structure and no unwanted phase was observed. Ultraviolet-visible analysis of the synthesized powder revealed that the main peak for the silver nanoparticles appeared in the wavelength range of 400 to 450 nm. DLS analysis revealed that precursor's particles inside the sol were below 15 nm. Based on AFM and TEM investigations, the particles synthesized under these conditions had nanometric spherical morphology with uniform particle size distribution.

scholarly journals Microwave-assisted green synthesis of silver nanoparticles using dried extracts of Chlorella vulgaris and antibacterial activity studies

2020 ◽  
Vol 9 (1) ◽  
pp. 283-293
Author(s):  
Milad Torabfam ◽  
Meral Yüce
Keyword(s):  
Silver Nanoparticles ◽  
Green Synthesis ◽  
Chlorella Vulgaris ◽  
Metallic Nanoparticles ◽  
Nitrate Solution ◽  
Spherical Shape ◽  
Silver Nitrate Solution ◽  
Spectroscopy Analysis ◽  
Bacterial Diseases ◽  
Serovar Typhimurium

AbstractGreen synthesis of metallic nanoparticles (NPs) is acquiring considerable attention due to its environmental and economic superiorities over other methods. This study describes the practical synthesis of silver nanoparticles (AgNPs) through the reduction of silver nitrate solution using an algal source, Chlorella vulgaris, as the reducing as well as the stabilizing agent. The energy required for this synthesis was supplied by microwave radiation. The ultraviolet-visible spectroscopy exhibited a single peak related to the surface plasmon absorbance of AgNPs at 431 nm. The AgNPs with high stability (a zeta potential of −17 mV), hydrodynamic size distribution of 1–50 nm, and mostly spherical shape were obtained through a 10 min process. Fourier transform infrared spectroscopy analysis revealed that several functional groups, including carbonyl groups of C. vulgaris, play a significant role in the formation of functional NPs. Antibacterial features of the produced AgNPs were verified against those of Salmonella enterica subsp. enterica serovar typhimurium and Staphylococcus aureus, demonstrating a considerable growth inhibition at increasing concentrations of the NPs. As a result, the formed AgNPs can be used as a promising agent against bacterial diseases.

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