Novel Design, Preparation, Characterization and Antimicrobial Activity of Silver Nanoparticles during Oak Acorns Bark Retrograde

2018 ◽  
Vol 232 (2) ◽  
pp. 209-221 ◽  
Author(s):  
Iraj Mesgarzadeh ◽  
Ali Reza Akbarzadeh ◽  
Rahmatollah Rahimi ◽  
Ali Maleki

AbstractIn search for a probable local solution for Qarasu River problems and based on our prescience about metal ion chelating/reducing ability of tannins which are found in large amount in oak acorns bark, Quercus brantii (Persian oak) acorns bark extract was exploited as reducing/capping agent in silver nanoparticles synthesis. Synthesis was carried out as a single-step method at room temperature, and without consuming any external energy by using these renewable barks. The crystallinity, size and shape of the nanoparticles were characterized by X-ray diffraction and scanning electron microscopy (SEM) respectively. The involvement of phenolic compounds in metal ion reduction was supported by UV-Visible and infrared spectroscopies and by acidity and conductivity measurements. The SEM-based particle size distribution analysis and antimicrobial susceptibility test of oak acorns bark-extract-mediated silver nanoparticles against bacterial effluent were pointed out to the critical proportion of silver salt to the capping/reducing agent. It seems that the bactericidal action depends on the extent to which accumulation of silver nanoparticle (Ag-Np) in bacterial cell surface alters the silver nanoparticle colloidal stability in broth medium.

2015 ◽  
Vol 3 (4) ◽  
pp. 603-611 ◽  
Author(s):  
Zengqian Shi ◽  
Juntao Tang ◽  
Li Chen ◽  
Chuanren Yan ◽  
Shazia Tanvir ◽  
...  

Preparation of polydopamine functionalized CNCs and silver nanoparticle immobilized CNCs.


Antioxidants ◽  
2019 ◽  
Vol 8 (10) ◽  
pp. 459 ◽  
Author(s):  
Tanase ◽  
Berta ◽  
Coman ◽  
Roșca ◽  
Man ◽  
...  

Green synthesis is one of the rapid and best ways for silver nanoparticles (AgNP) synthesis. In the present study, synthesis and bioactivity of AgNPs has been demonstrated using water beech (Fagus sylvatica L.) bark extract. The physical and chemical factors such as time, metal ion solution, and pH, which play a vital role in the AgNPs synthesis, were assessed. The AgNPs were characterized by ultraviolet-visible (UV-Vis) spectrometry, Fourier transform infrared spectroscopy (FT-IR), and transmission electron microscopy (TEM). Antioxidant and antimicrobial activity of the obtained AgNPs was evaluated. AgNPs were characterized by color change pattern, and the broad peak obtained at 420–475 nm with UV-Vis confirmed the synthesis of AgNPs. FT-IR results confirmed that phenols and proteins of beech bark extract are mainly responsible for capping and stabilization of synthesized AgNPs. TEM micrographs showed spherical or rarely polygonal and triangular particles with an average size of 32 nm at pH = 9, and 62 nm at pH = 4. Furthermore, synthesized AgNPs were found to exhibit antioxidant activity and have antibacterial effect against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and Pseudomonas aeruginosa. These results indicate that bark extract of F. sylvatica L. is suitable for synthesizing stable AgNPs, which act as an excellent antimicrobial agent.


2014 ◽  
Vol 13 (03) ◽  
pp. 1450021 ◽  
Author(s):  
Nityananda Agasti ◽  
N. K. Kaushik

This paper presents a simple and convenient procedure for the preparation of octyl amine capped silver nanoparticles. AgNO 3 has been reduced by octyl amine with benzene or toluene as solvent at 100°C to produce silver nanoparticles. Octyl amine plays its role both as reducing and capping agent and thus provides the advantage of avoiding the use of extra stabilizing agent. Time dependent formation mechanism of silver nanoparticle has been investigated. Thermo gravimetric analysis (TGA) shows weight change due to loss of capping agent. The reaction can easily be monitored from variation of color with time. The method is easy and reproducible. Very low concentration (1 mM) of metal ion is used. The particles synthesized were characterized by UV-Visible, FTIR, TGA, TEM and X-ray diffraction studies.


Author(s):  
Pallavi Sharma ◽  
Valentina V Umrania

The research was carried out to investigate the synthesis of silver nano particles. The silver nano particles have wide tremendous application in the therapeutics, antimicrobials, diagnostics, catalysis, micro-electronics and high sensitivity biomolecular detection.  Silver nano particles grow in a single-step method, at room temperature, and with no addition of external energy. The silver nanoparticles were synthesized from silver nitrate aqueous solution through a simple, eco-friendly and cost effective course using the leaf broth of the Oscimum sanctum, Azadirachtaindica and LawsoniaInermis (kadvi mehndi), therefore calling it green synthesis. The Synthesized AgNP was confirmed by sampling the aqueous component at different time intervals and the absorption maxima was scanned by UV-Vis spectrometry and Particle Size Distribution (PSD). Based on PSD, the particles were further characterized by Scanning Electron Microscope. Synthesized AgNP was confirmed at 531,540and 543 nm. Among the total percentage of size distribution, D-50 value, which is 50% size distribution, was taken into consideration, where the size of the nanoparticle was established to 0.135µm. Further research is going on with reference to the synthesized nanoparticles.


Nanomaterials ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 1541 ◽  
Author(s):  
Corneliu Tanase ◽  
Lavinia Berta ◽  
Năstaca Alina Coman ◽  
Ioana Roșca ◽  
Adrian Man ◽  
...  

Biosynthesized silver nanoparticles (AgNPs) are widely used in Pharmacy and Medicine. In particular, AgNPs synthesized and mediated by plant extracts have shown topossess several biological activities. In the present study, AgNPs were synthesized using Picea abies L. stem bark extract as reducing agent. Factors, such as metal ion solution, pH, and time, which play a role in the AgNPs synthesis, were assessed. The synthesized AgNPs were characterized by Ultraviolet-Visible Spectrometry, Fourier transform infrared spectroscopy, and Transmission Electron Microscopy (TEM). Further, the study has been extended to evaluate the antimicrobial and antioxidant activity of AgNPs. The broad peak obtained at 411–475 nm (UV-Vis spectroscopy), and the color change pattern, confirmed the synthesis of AgNPs. TEM results showed spherical or rarely polygonal AgNPs with an average size of 44 nm at pH = 9. The AgNPs showed antioxidant activity and antibacterial effect against human pathogenic Gram-positive and Gram-negative bacteria. The results show that spruce bark extract is suitable for obtaining AgNPs, with antibacterial and antioxidant activity.


2021 ◽  
Author(s):  
Monikankana Saikia ◽  
Tonkeswar Das ◽  
Binoy K Saikia

Silver nanoparticles/nanocomposites are gaining popularity for their unique features and wide-range of applications including bactericidal behaviour, sensing, and photocatalysis. In this report, a novel, single-step, sustainable, and low-cost fabrication of...


1983 ◽  
Vol 49 (01) ◽  
pp. 024-027 ◽  
Author(s):  
David Vetterlein ◽  
Gary J Calton

SummaryThe preparation of a monoclonal antibody (MAB) against high molecular weight (HMW) urokinase light chain (20,000 Mr) is described. This MAB was immobilized and the resulting immunosorbent was used to isolate urokinase starting with an impure commercial preparation, fresh urine, spent tissue culture media, or E. coli broth without preliminary dialysis or concentration steps. Monospecific antibodies appear to provide a rapid single step method of purifying urokinase, in high yield, from a variety of biological fluids.


Author(s):  
С.И. Каба ◽  
А.А. Соколовская

Продемонстрировано обнаружение наночастиц серебра во внутриклеточном пространстве с помощью проточной цитофлуориметрии. В эндотелиальных клетках линии EA.hy926, инкубированных в растворе, содержащем 2 мкг/мл наносеребра, измеряли боковое светорассеяние. По сравнению с контрольными образцами этот параметр возрастал, в то время как прочие значимые характеристики не изменялись. Это подтверждает чувствительность метода к изменившемуся состоянию клеток и указывает на поглощение наночастиц серебра клетками при концентрации ниже токсической. The study demonstrated a possibility for detection of intracellular silver nanoparticles using flow cytometry. The parameter used in this work, side scattering, was measured in EA.hy926 endothelial cells incubated in a 2 mg/ml silver nanoparticle solution. This parameter was increased compared to control samples. Therefore, this technique was sensitive to changes in the cell status and suggested the cell uptake of the particles under the subtoxic conditions.


Sign in / Sign up

Export Citation Format

Share Document