scholarly journals Development and Characterization of Semi-IPN Silver Nanocomposite Hydrogels for Antibacterial Applications

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
A. Chandra Babu ◽  
M. N. Prabhakar ◽  
A. Suresh Babu ◽  
B. Mallikarjuna ◽  
M. C. S. Subha ◽  
...  

Sodium carboxymethyl cellulose/poly(acrylamide-co-2-acrylamido-2-methylpropane sulfonic acid) semi-interpenetrating polymer network (semi-IPN) hydrogels were prepared by using free radical polymerization technique. Silver nanoparticles were formed by reduction of silver nitrate in semi-IPN hydrogels with sodium borohydrate at room temperature. UV-visible spectroscopy, thermogravimetrical analysis, X-ray diffractometry, scanning electron microscopy, and transmission electron microscopy techniques were used to characterize the formation of silver nanoparticles in hydrogels. SEM images indicated clearly the formation of group of silver nanoparticles with size range of 10–20 nm. The sizes of silver nanoparticles were also supported by transmission electron microscopy results. The semi-IPN silver nanocomposite hydrogels reported here might be a potentially smart material in the range of applications of antibacterial activity.

Separations ◽  
2021 ◽  
Vol 8 (1) ◽  
pp. 8
Author(s):  
Kollur Shiva Prasad ◽  
Shashanka K Prasad ◽  
Ravindra Veerapur ◽  
Ghada Lamraoui ◽  
Ashwini Prasad ◽  
...  

Herein we report the synthesis of zinc oxide nanoparticles (ZnONPs) using Withania somnifera root extract (WSE) as an effective chelating agent. The microscopic techniques viz., X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and selected area electron diffraction (SAED) were employed to analyze the as-obtained ZnONPs. The crystalline planes observed from the XRD pattern agrees with the hexagonal wurtzite structure of the as-prepared ZnONPs. The aggregations and agglomerations observed in the SEM images indicated that the size of the as-prepared ZnONPs was between 30 and 43 nm. The interplanar distance between the lattice fringes observed in the HRTEM image was found to be 0.253 nm, which is in good agreement with the (100) plane obtained in the XRD pattern. Furthermore, the anti-breast cancer cytotoxic evaluation was carried out using the MCF-7 cell line, and the results showed significant cytotoxic effects in a dose-dependent manner.


Author(s):  
Nabraj Bhattarai ◽  
Subarna Khanal ◽  
Pushpa Raj Pudasaini ◽  
Shanna Pahl ◽  
Dulce Romero-Urbina

Citrate stabilized silver (Ag) colloidal solution were synthesized and characterized for crystallographic and surface properties by using transmission electron microscopy (TEM) and zeta potential measurement techniques. TEM investigation depicted the size of Ago ranges from 5 to 50 nm with smaller particles having single crystal structure while larger particles with structural defects (such as multiply twinned, high coalescence and Moire patterns). ?-potential measurement confirms the presence of Ag+ in nAg stock solution. The shift in ?-potential measurement by +25.1 mV in the filtered solution suggests the presence of Ag+ in Ago nanoparticles.


2019 ◽  
Vol 19 (11) ◽  
pp. 7487-7492 ◽  
Author(s):  
Supriya ◽  
Jayanta Kumar Basu ◽  
Sonali Sengupta

Synthesis of silver nanoparticles embedded on calcium alginate film and the catalytic property of this film in the reduction of nitrobenzene with sodium borohydride are demonstrated in this work. Natural polymer alginate acts as effective reducing and stabilizing agent in synthesis of silver nanoparticles. Effect of different parameters on the preparation of silver nanoparticles, such as, temperature, concentration of silver precursor and heating time was investigated. As-prepared silver nanoparticles were characterized by transmission electron microscopy, scanning electron microscopy, UV-Vis spectrometry, and atomic absorption spectrometry. Transmission electron microscopy analysis con-firms the formation of silver nanoparticles with particles size range of 3–19 nm and average particle size was found to be 10±4 nm. Effect of concentration of nitrobenzene and sodium borohydride, catalyst loading and temperature on the catalytic reduction of nitrobenzene was studied. Reusability of catalyst was examined in this reduction reaction and the catalyst shows good activity up to 10th run.


2003 ◽  
Vol 779 ◽  
Author(s):  
Hyung Seok Kim ◽  
Sang Ho Oh ◽  
Ju Hyung Suh ◽  
Chan Gyung Park

AbstractMechanisms of misfit strain relaxation in epitaxially grown Bi4-xLaxTi3O12 (BLT) thin films deposited on SrTiO3 (STO) and LaAlO3 (LAO) substrates have been investigated by means of transmission electron microscopy (TEM). The misfit strain of 20 nm thick BLT films grown on STO substrate was relaxed by forming misfit dislocations at the interface. However, cracks were observed in 100 nm thick BLT films grown on the same STO. It was confirmed that cracks were formed because of high misfit strain accumulated with increasing the thickness of BLT, that was not sufficiently relaxed by misfit dislocations. In the case of the BLT film grown on LAO substrate, the magnitude of lattice misfit between BLT and LAO was very small (~1/10) in comparison with the case of the BLT grown on STO. The relatively small misfit strain formed in layered structure of the BLT films on LAO, therefore, was easily relaxed by distorting the film, rather than forming misfit dislocations or cracks, resulting in misorientation regions in the BLT film.


Biomolecules ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 982 ◽  
Author(s):  
Kollur Shiva Prasad ◽  
Shashanka K. Prasad ◽  
Mohammad Azam Ansari ◽  
Mohammad A. Alzohairy ◽  
Mohammad N. Alomary ◽  
...  

In this work, we aimed to synthesize zinc oxide nanoparticles (ZnONPs) using an aqueous extract of Cassia auriculata leaves (CAE) at room temperature without the provision of additional surfactants or capping agents. The formation of as-obtained ZnONPs was analyzed by UV–visible (ultraviolet) absorption and emission spectroscopy, X-ray photoemission spectroscopy (XPS), X-ray diffraction analysis (XRD), energy dispersive X-ray diffraction (EDX), thermogravimetric analysis/differential thermal analysis (TGA-DTA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and selected area electron diffraction (SAED). The XRD results reflect the wurtzite structure of as-prepared ZnONPs, which produced diffraction patterns showing hexagonal phases. The SEM images indicate that the morphology of as-prepared ZnONPs is composed of hexagonal nanostructures with an average diameter of 20 nm. The HR-TEM result shows that the inter-planar distance between two lattice fringes is 0.260 nm, which coincides with the distance between the adjacent (d-spacing) of the (002) lattice plane of ZnO. The fluorescence emission spectrum of ZnONPs dispersed in ethanol shows an emission maximum at 569 nm, revealing the semiconductor nature of ZnO. As-obtained ZnONPs enhanced the tumoricidal property of CAE in MCF-7 breast cancer cells without significant inhibition of normal human breast cells, MCF-12A. Furthermore, we have studied the antibacterial effects of ZnONPs, which showed direct cell surface contact, resulting in the disturbance of bacterial cell integrity.


2013 ◽  
Vol 872 ◽  
pp. 74-78 ◽  
Author(s):  
S.P. Zhuravkov ◽  
Evgeny Plotnikov ◽  
Dmitry Martemiyanov ◽  
Nikolay A. Yavorovsky ◽  
Ulrich Hasse ◽  
...  

The morphological and structural characteristics of nanoscale silver particles obtained by the method of electric spark dispersion of metal granules in the liquid aprotic medium were obtained using atomic force microscopy, transmission electron microscopy, and dynamic light scattering spectroscopy. The specific surface, morphology, structure and the distribution by size of the particles are presented.


2017 ◽  
Vol 263 ◽  
pp. 165-169
Author(s):  
Silvia Chowdhury ◽  
Faridah Yusof ◽  
Nadzril Sulaiman ◽  
Mohammad Omer Faruck

In this article, we have studied the process of silver nanoparticles (AgNPs) aggregation and to stop aggregation 0.3% Polyvinylpyrrolidone (PVP) was used. Aggregation study carried out via UV-vis spectroscopy and it is reported that the absorption spectrum of spherical silver nanoparticles were found a maximum peak at 420 nm wavelength. Furthermore, Transmission Electron Microscopy (TEM) were used to characterized the size and shape of AgNPs, where the average particle size is around 10 to 25 nm in diameter and the AgNPs shape is spherical. Next, Dynamic Light Scattering (DLS) were used, owing to observed size distribution and self-correlation of AgNPs.


2006 ◽  
Vol 6 (1) ◽  
pp. 130-134 ◽  
Author(s):  
Olivier Balmes ◽  
Jan-Olov Bovin ◽  
Jan-Olle Malm

Gold nanoparticles (5 nm and 20 nm) have been synthesized and stabilized with mercaptoundecanol. These particles, although insoluble in water or common organic solvents, spread as a thin film at the liquid–liquid interface between a water phase and an organic phase. Films of these gold nanoparticles have been observed both by conventional transmission electron microscopy of deposited samples and by cryo-transmission electron microscopy of plunge-frozen samples. The film can be monolayered and extend over centimeter-sized areas. The particle films spontaneously re-assemble and self-organize at the interface when disrupted. This self-healing capacity of the film should make it possible to build a device for continuous production and deposition of the film.


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