scholarly journals Optical and Photoacoustic Properties of Colloidal Silver Nanoparticles Solutions

2018 ◽  
Vol 7 (4) ◽  
pp. 1 ◽  
Author(s):  
F. Aldosari ◽  
A. M. Azzeer ◽  
A. M. Hassib

The study has aimed to investigate optical and photoacoustic properties of some colloidal silver nanoparticles at different concentration over the time. The phase purity with crystal structure of silver nanoparticles were studied using X-ray diffraction (XRD) and was confirmed by Transmission Electron Microscopy (TEM). Optical property was changed during the variable concentration of nanoparticles and duration time of sample. The absorbance of silver colloidal solutions is increased, when concentration increases but decreased with respective to the longer period of sample. Absorption peaks and stability of particles in solutions is influenced by the duration time of solution and its concentration. The low concentration-based solutions fall in the absorbance over the times. The observed PA signal is subjected by the factor of parameters; such as, pump wavelengths, energy, repetition rate, concentrations, and temperature. Stability of fluorescence and absorption peaks are influenced by the concentration of particles and time period of colloidal solution. Effects on PA signal with fluorescent and absorption peaks upon the concentration was also significant.

2012 ◽  
Vol 488-489 ◽  
pp. 1409-1413
Author(s):  
Adeleh Granmayeh Rad ◽  
Hamed Abbasi

In this work we report the preparation of colloidal silver nanoparticles. In order to prepare the silver nanoparticles laser ablation method has been used.A silver coin as a target (purity 99.9 %) was ablated by a Q-Switched Nd:YAG laser with a fluence of about 91 mJ/cm2 at a repetition rate of 10 Hz at room temperature. In order to evaluate these particles transmission electron microscopy (TEM) and spectrophotometry (from UV to NIR) have been used. The average size of prepared nanoparticles is ~ 20 nm. The importance of morphology of nanoparticles has been investigated. Developed applications of silver nanoparticles have been studied,silver nanoparticles are considered as biocompatible and low in toxicity and have good potential for biological applications. Lately silver nanoparticles have found a novel approach in different fields of medicine, biology and industry.


Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2006 ◽  
Author(s):  
Alexey Lezov ◽  
Alexander Gubarev ◽  
Maria Mikhailova ◽  
Alexandra Lezova ◽  
Nina Mikusheva ◽  
...  

The interaction of silver nitrate with star-shaped poly(2-ethyl-2-oxazoline) and poly(2-isopropyl-2-oxazoline) containing central thiacalix[4]arene cores, which proceeds under visible light in aqueous solutions at ambient temperature, was studied. It was found that this process led to the formation of stable colloidal solutions of silver nanoparticles. The kinetics of the formation of the nanoparticles was investigated by the observation of a time-dependent increase in the intensity of the plasmon resonance peak that is related to the nanoparticles and appears in the range of 400 to 700 nm. According to the data of electron and X-ray spectroscopy, scanning and transmission electron microscopy, X-ray diffraction analysis, and dynamic light scattering, the radius of the obtained silver nanoparticles is equal to 30 nm. In addition, the flow birefringence experiments showed that solutions of nanoparticles have high optical shear coefficients.


2015 ◽  
Vol 1101 ◽  
pp. 138-143 ◽  
Author(s):  
Harjono ◽  
Yoki Yulizar

In this paper we report the effect of irradiation time on the morphological and dimensional properties of colloidal silver nanoparticles (AgNPs) using sodium citrate and silver nitrate as reductant and oxidant, respectively under microwave irradiation. The prepared NPs were characterized by UV–vis spectroscopy, Particle size analyzer (PSA), transmission electron microscopy (TEM) and selected areas electron diffraction (SAED). The formation of Ag NPs was confirmed by the appearance of a surface plasmon absorption between 411-425 nm. PSA showed that the colloidal nanoparticles had a diameters ranging from 25.5-41.2 nm. TEM images showed that the diameter of the silver nanoparticles in accordance with the results obtained using PSA. The rings patterns are in good agreement with the standard values of the facecentered-cubic form of silver nanocrystals.


Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2326
Author(s):  
Entesar Ali Ganash ◽  
Reem Mohammad Altuwirqi

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.


2013 ◽  
Vol 11 (1) ◽  
pp. 44-51 ◽  
Author(s):  
Ruixue Wang ◽  
Shasha Zuo ◽  
Weidong Zhu ◽  
Shan Wu ◽  
Weifeng Nian ◽  
...  

2010 ◽  
Vol 79 (12) ◽  
pp. 1203-1208 ◽  
Author(s):  
Kazem Naghavi ◽  
Elias Saion ◽  
Khadijeh Rezaee ◽  
Wan Mahmood Mat Yunus

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Hernane S. Barud ◽  
Thaís Regiani ◽  
Rodrigo F. C. Marques ◽  
Wilton R. Lustri ◽  
Younes Messaddeq ◽  
...  

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.


2021 ◽  
Vol 891 ◽  
pp. 111-115
Author(s):  
Maradhana Agung Marsudi ◽  
Farah Fitria Sari ◽  
Pandu Mauliddin Wicaksono ◽  
Adinda Asmoro ◽  
Arif Basuki ◽  
...  

In this work, silver nanoparticles have been successfully synthesized using simple and environmentally friendly ‘green synthesis’ method using Indonesian wild honey as mediator. Particle count and size can be optimized by varying the silver nitrate precursor and honey concentration, with the help of sodium hydroxide as pH regulator. Based on X-ray diffraction (XRD) result, crystalline structure of Ag has been confirmed in sample with impurities from AgCl. Based on dynamic light scattering (DLS) and transmission electron microscopy (TEM) results, it was found that the smallest average particles size of AgNPs (117.5 nm from DLS and 11.1 nm from TEM) was obtained at sample with 5% w/v of honey and 0.5 mM of AgNO3.


Author(s):  
Shyla Marjorie Haqq ◽  
Amit Chattree

  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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