Tunable Silver Leaching from Polyelectrolyte Multilayers Thin Films

2013 ◽  
Vol 701 ◽  
pp. 145-149 ◽  
Author(s):  
Sirorat Wacharanad ◽  
Stephan Thierry Dubas
Keyword(s):  
Silver Nanoparticles ◽  
Suture Material ◽  
Chemical Reduction ◽  
Layer By Layer ◽  
Capping Agent ◽  
Bacterial Reduction ◽  
Bacterial Colony ◽  
Surgical Suture ◽  
Layer Deposition ◽  
Vis Spectroscopy

Silver nanoparticles were deposited on glass slides and surgical suture as antibacterial agent. The silver nanoparticles were prepared by chemical reduction with sodium borohydride and using a synthetic polyelectrolyte as capping agent. Poly (4-styrenesulfonic acid-co-maleic acid) sodium salt PSSMA was used to stabilize the silver nanoparticles and provide an anionic surface charge which then allowed the layer-by-layer deposition method with poly (dially dimethyl ammonium chloride) PDADMAC. Various concentration of capping agent were used to prepare the silver nanoparticles which were then deposited on glass slide and surgical suture. The layer-by-layer deposition of the nanoparticles was studied using UV-Vis spectroscopy by monitoring the intensity of the characteristic Plasmon band of the nanoparticles at 400nm. The leaching of the silver nanoparticles in buffered solutions of pH 3,7 and 9 was monitored by recording the decrease in absorbance of silver nanoparticles film as a function of time for each pH solutions and each capping concentrations. Finally, suture material coated with silver nanoparticles were tested for their antibacterial activity against Staphylococcus aureus and results showed that all coated sutures had more than 99% bacterial reduction. So these suture material could be applied to use in medical products for promoted wound healing and decreased bacterial colony leading to relieve inflammation of patient.

Facile Synthesis of Silver Nanoparticles by Chemical Reduction Route

2013 ◽  
Vol 756 ◽  
pp. 99-105
Author(s):  
Rajasingam Ratnamalar ◽  
Mustapha Mariatti ◽  
Zulkifli Ahmad ◽  
Sharif Zein Sharif Hussein
Keyword(s):  
Silver Nanoparticles ◽  
Ag Nanoparticles ◽  
Chemical Reduction ◽  
Facile Synthesis ◽  
Cubic Lattice ◽  
Vis Spectroscopy ◽  
Simple Chemical ◽  
The Face ◽  
Fine Control ◽  
Xrd Patterns

This work reports a simple chemical reduction route for the preparation of uniformed Ag nanoparticles whereby a fine control over the sizes of the Ag nanoparticles was studied by varying the concentrations of the reducing agents used. In characterization, UV-Vis spectroscopy showed the changes in optical properties of the Ag nanoparticles with regards to their sizes, where as the XRD patterns of the synthesized Ag nanoparticles confirmed the distinct peaks approximately at 2θ = 38.1°, 44.3°, 64.4°, 77.4°, and 81.5 representing Bragg’s reflections from (111), (200), (220), (311), and (222) planes of the face centred cubic lattice phase. This route of synthesis is feasible to produce Ag nanoparticles with diameters in the range of 30-45 nm.

Synthesis of Uniform and High Density Silver Nanoparticles by using Peltophorum pterocarpum flower Extract

2014 ◽  
Vol 1584 ◽  
Author(s):  
Matheswaran BALAMURUGAN ◽  
Shanmugam SARAVANAN ◽  
Naoki OHTANI
Keyword(s):  
Silver Nanoparticles ◽  
Fourier Transform ◽  
Electron Microscope ◽  
Ultra Violet ◽  
Capping Agent ◽  
Nanosized Particles ◽  
Flower Extract ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Ft Ir

ABSTRACTSilver nanoparticle (AgNP) is one of the elegant material because its uses in various fields. In this study, AgNPs have been prepared by using Peltophorum pterocarpum (PP) flower extract as reducing and capping agent and aqueous silver nitrate (aq.AgNO3) as silver precursor. The synthesized nanoparticles were characterized using Ultra Violet - Visible (UV-Vis) spectroscopy, High Resolution Transmission Electron Microscope (HR-TEM) and Fourier Transform Infrared Spectroscopy (FT-IR), which reveals the formation of nanosized particles. The UV-Vis spectrum shows an absorption peak around 430nm. HR-TEM images of AgNPs with clear morphology and well dispersed prepared AgNPs.

scholarly journals Highly Sensitive and Selective Colorimetric Sensor of Mercury (II) Based on Layer–by–Layer Deposition of Gold/Silver Bimetallic Nanoparticles

Molecules ◽  
2020 ◽  
Vol 25 (19) ◽  
pp. 4443
Author(s):  
Arjnarong Mathaweesansurn ◽  
Naratip Vittayakorn ◽  
Ekarat Detsri
Keyword(s):  
Bimetallic Nanoparticles ◽  
Limit Of Detection ◽  
Chemical Reduction ◽  
Colorimetric Sensor ◽  
Layer By Layer ◽  
Linear Relationships ◽  
Layer Deposition ◽  
Gold Silver ◽  
Ft Ir ◽  
Uv Visible

A new colorimetric sensor based on gold/silver bimetallic nanoparticles (Au–Ag BNPs) for the sensitive and selective detection of mercury (II) was developed. Gold nanoparticles (AuNPs) were synthesized by Turkevich method. The surface modification of AuNPs was modified by the layer–by–layer technique using poly(diallyl dimethylammonium chloride) which provided positively charged of AuNPs. Negatively charged silver nanoparticles (AgNPs) were synthesized by chemical reduction using poly(4–styrenesulfonic acid–co–maleic acid) as the stabilizing agent. The layer–by–layer assembly deposition technique was used to prepare Au–Ag BNPs of positively and negatively charged of AuNPs and AgNPs, respectively. The synthesized Au–Ag BNPs were characterized by a UV-visible spectrophotometer, zeta potential analyzer, FT–IR, TEM, XRD, and EDX. The Au–Ag BNPs sensor was able to detect mercury (II) in aqueous solution, visibly changing from brownish–orange to purple. The linear relationships of the UV-visible spectrometry demonstrate that the Au–Ag BNPs-based colorimetric sensor can be used for the quantitative analysis of mercury (II) in the range of 0.5–80 mg L−1, with the correlation coefficient, r2 = 0.9818. The limit of detection (LOD) of mercury (II) was found to be 0.526 + 0.001 mg L−1. The BNPs is also verified to have a good practical applicability for mercury (II) detection in the real samples.

Effect of Surfactant on the Morphology of Silver Nanoparticles

2007 ◽  
Vol 124-126 ◽  
pp. 1205-1208 ◽  
Author(s):  
Keun Ju Park ◽  
Dong Seok Seo ◽  
Woo Yang Jang ◽  
Jong Kook Lee
Keyword(s):  
Silver Nanoparticles ◽  
Ascorbic Acid ◽  
Low Temperature ◽  
Reduction Method ◽  
Chemical Reduction ◽  
Sodium Dodecyl ◽  
Capping Agent ◽  
Silver Particles ◽  
Chemical Reduction Method ◽  
20 Nm

Nano-sized silver particles are considered to apply a silver paste for electrode because of its high conductivity on sintering at low temperature. In this study, silver nanoparticles as seeds were prepared by chemical reduction method with capping agent. Silver particles were prepared using SDS (Sodium dodecyl sulfate) as a surfactant and silver nanoparticles as seeds and reacted with ascorbic acid as a reduction agent. The silver seeds with 10-20 nm in size with uniform distribution were formed and the size and shape of silver particles were strongly dependent on the concentration of surfactant.

Preparation and characterization of silver nanoparticle-porphyrazine composites

2013 ◽  
Vol 17 (10) ◽  
pp. 928-933
Author(s):  
Altuğ Mert Sevim ◽  
Ayşe Selda Keskin ◽  
Ahmet Gül
Keyword(s):  
Silver Nanoparticles ◽  
Chemical Reduction ◽  
Reduction Process ◽  
Silver Ions ◽  
Organic Medium ◽  
Nano Particles ◽  
Effective Manner ◽  
Vis Spectroscopy ◽  
One Step

A one step chemical reduction process was used for the preparation of hydrophilic silver nanoparticles ( AgNP ) using silver nitrate, sodiumborohydride and polyvinylpyrolidone as stabilizer. In the case of hydrophobic silver nanoparticles reduced silver ions were stabilized with cetyl trimethylammonium bromide (CTAB). The resultant nano particles were characterized by absoption spectra and their interactions with cationic cobalt (QCoPz) and neutral magnesium (MgPz) porphyrazines in water and in organic medium were investigated by using UV-vis spectroscopy and zeta potential techniques. It is confirmed that both metalloporphyrazine molecules interact with silver nanoparticles in an effective manner. The possible arrangement of the porphyrazines on the surfaces of the hydrophilic and hydrophobic AgNPs has been also discussed according to obtained spectroscopic results. These well-characterized novel AgNP -metalloporphyrazine composites are expected to be useful in optical and catalytic applications.

Silver Nanoparticles for SERS Identification of Dyes

2012 ◽  
Vol 1374 ◽  
pp. 263-274 ◽  
Author(s):  
Edgar Casanova-González ◽  
Angélica García-Bucio ◽  
José Luis Ruvalcaba-Sil ◽  
Víctor Santos-Vasquez ◽  
Baldomero Esquivel ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Sodium Citrate ◽  
Chemical Reduction ◽  
Raman Signal ◽  
Carminic Acid ◽  
Sers Substrate ◽  
Gold And Silver Nanoparticles ◽  
Preparation Methods ◽  
Vis Spectroscopy ◽  
Coinage Metals

ABSTRACTCoinage metals nanoparticles have been widely used in last decade for enhancing the Raman signal of a variety of compounds. Several preparation methods have been proposed, including chemical reduction of gold or silver salts with sodium citrate, hydroxylamine or sodium borohydride, microwave-assisted reduction with glucose, Tollens mirror, electrodeposition, vacuum evaporation and pulsed-laser deposition.In this work, gold and silver nanoparticles were prepared by chemical reduction with sodium citrate and hydroxilmanine, characterized by UV-Vis spectroscopy and High Resolution Transmission Electronic Microscopy and tested as SERS substrate. Carminic acid, cochineal, axiote, muitle and zacatlaxcalli SERS spectra were recorded at different pH. Natural dyes samples were prepared by extraction from its natural sources, following traditional recipes. Although differs for each dye, best results were achieved by performing SERS experiments at pH neutral to basic.

scholarly journals Nanostructural Features of Silver Nanoparticles Powder Synthesized through Concurrent Formation of the Nanosized Particles of Both Starch and Silver

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
A. Hebeish ◽  
M. H. El-Rafie ◽  
M. A. El-Sheikh ◽  
Mehrez E. El-Naggar
Keyword(s):  
Particle Size ◽  
Silver Nanoparticles ◽  
Zeta Potential ◽  
High Speed ◽  
Chemical Reduction ◽  
Reduction Process ◽  
Nanosized Particles ◽  
High Concentration ◽  
Particle Size Analyzer ◽  
Vis Spectroscopy

Green innovative strategy was developed to accomplish silver nanoparticles formation of starch-silver nanoparticles (St-AgNPs) in the powder form. Thus, St-AgNPs were synthesized through concurrent formation of the nanosized particles of both starch and silver. The alkali dissolved starch acts as reducing agent for silver ions and as stabilizing agent for the formed AgNPs. The chemical reduction process occurred in water bath under high-speed homogenizer. After completion of the reaction, the colloidal solution of AgNPs coated with alkali dissolved starch was cooled and precipitated using ethanol. The powder precipitate was collected by centrifugation, then washed, and dried; St-AgNPs powder was characterized using state-of-the-art facilities including UV-vis spectroscopy, Transmission Electron Microscopy (TEM), particle size analyzer (PS), Polydispersity index (PdI), Zeta potential (ZP), XRD, FT-IR, EDX, and TGA. TEM and XRD indicate that the average size of pure AgNPs does not exceed 20 nm with spherical shape and high concentration of AgNPs (30000 ppm). The results obtained from TGA indicates that the higher thermal stability of starch coated AgNPS than that of starch nanoparticles alone. In addition to the data obtained from EDX which reveals the presence of AgNPs and the data obtained from particle size analyzer and zeta potential determination indicate that the good uniformity and the highly stability of St-AgNPs).

scholarly journals Photo-induced chemical reduction of silver bromide to silver nanoparticles

2011 ◽  
Vol 9 (6) ◽  
pp. 982-989 ◽  
Author(s):  
Agnieszka Król-Gracz ◽  
Ewa Michalak ◽  
Piotr Nowak ◽  
Agnieszka Dyonizy
Keyword(s):  
Silver Nanoparticles ◽  
Chemical Reduction ◽  
Silver Bromide ◽  
Molar Ratio ◽  
Efficient Production ◽  
Ag Nps ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Nanoparticle Suspensions ◽  
Actinic Radiation

AbstractThis paper discusses the experimental results of the production of nanocolloidal silver using photoreduction method. Ultrafine crystalline gelatine-stabilised aqueous suspensions of silver bromide were used as a substrate for the synthesis of silver nanoparticles (Ag NPs). The influences of the reductant to substrate molar ratio, the medium’s pH, the type of the source of actinic radiation and the time of exposure to the efficient production of the Ag NPs were studied. A typical reaction was suggested, which involves the photo-induced reduction of silver bromide nanocrystals in the presence of ascorbic acid under specified physicochemical conditions. The properties of resultant silver particles were examined using UV-Vis spectroscopy and Dynamic Light Scattering (DLS). In addition, Transmission Electron Microscopy (TEM) was used for imaging the silver nanoparticle suspensions.

Fabrication of Electrochemical Ceramic Membrane with Assistance of Metallization by the Electroless-plating Technique

2002 ◽  
Vol 752 ◽  
Author(s):  
Y-Y. Liu ◽  
L. Hong ◽  
Z-C. Shao ◽  
H-X. Jiang
Keyword(s):  
Structural Integrity ◽  
Ceramic Membrane ◽  
Chemical Reduction ◽  
Dip Coating ◽  
Alloy Film ◽  
Layer By Layer ◽  
Plating Bath ◽  
Layer Deposition ◽  
Pd Alloy ◽  
Membrane Processing

ABSTRACTThis work developed a metal-reinforced ceramic membrane processing approach [by using perovskite La0.2Sr0.8 CoO3-x (LSCO-80) as the model membrane] with the aim of overcoming the membrane-cracking problem. A thin layer of Ag/Pd alloy was incorporated into the LSCO-80 membrane made by dip coating and sintering. It is not viable to obtain a Pd/Ag alloy film using the co-plating method because Ag+ ion strongly inhibits chemical reduction of Pd2+ ion, and the alkaline plating bath causes severe etching of LSCO-80. This obstacle was circumvented through a layer-by-layer deposition procedure, in which Ag and Pd layers were deposited subsequently onto LSCO membrane. The Ag and Pd layers undergo alloying when the laminar structure was subjected to calcinations at 1000°C. It was found that the Pd/Ag alloy drifts beneath into pores in the LSCO layer. The resultant metal-ceramic composite membrane shows excellent structural integrity and free of micro-cracks.

Sign in / Sign up

Export Citation Format

Share Document