A Study of the Effect of Polymer Matrix on the Ultrasonic Propagation in Silver Nanoparticles

In the present work, ultrasonic velocity measurements have been carried out in solutions of silver nanoparticles in the polymer matrix of poly(sodium, 4-styrene sulphonate) using Sing-Around technique, operated at 2 MHz.. The ultrasonic velocity of propagation shows an abnormal behaviour, indicating the existence of the phase separations in nano-colloidal solution. The effect of polymer is observed to be predominant in the phase separation at the lower concentrations of polymer in the mixture. At higher concentrations of the polymer in the mixture the phase separation seems to subside at higher temperature.

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Ultrasonic Characterization of Silver Nanoparticles

Journal of Metastable and Nanocrystalline Materials ◽

10.4028/www.scientific.net/jmnm.23.271 ◽

2005 ◽

Vol 23 ◽

pp. 271-274

Author(s):

S. Rajagopalan ◽

S.J. Sharma ◽

V.Y. Nanotkar

Keyword(s):

Silver Nanoparticles ◽

Ultrasonic Velocity ◽

Colloidal Solution ◽

Adiabatic Compressibility ◽

Ammonium Bromide ◽

Velocity Measurements ◽

Abnormal Behaviour ◽

Phase Separations ◽

Ultrasonic Characterization

Nanoparticles exhibit unusual properties in contrast with their bulk properties due to small particle size and quantum confinement. In the present work, ultrasonic velocity and density measurements have been carried out in solutions of silver nanoparticles in micellar dispersion of cetyl tri-metyl ammonium bromide, CTAB. Ultrasonic velocity measurements at different concentrations of surfactant and temperatures were carried out using Sing-Around technique, operated at 2MHz. It is observed that ultrasonic velocity and adiabatic compressibility show abnormal behaviour with increase in concentration of CTAB in the solution, indicating the existence of the phase separations in nano-colloidal solution.

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Antibacterial Activity of Biodegradable Particles based on Chitosan Containing Colloidal Silver

Biotekhnologiya ◽

10.21519/0234-2758-2020-36-4-87-93 ◽

2020 ◽

Vol 36 (4) ◽

pp. 87-93

Author(s):

V.Yu. Reshetova ◽

A.F. Krivoshchepov ◽

I.A. Butorova ◽

N.B. Feldman ◽

S.V. Lutsenko ◽

...

Keyword(s):

Silver Nanoparticles ◽

Antibacterial Activity ◽

Polymer Matrix ◽

Adipic Acid ◽

Antibacterial Effect ◽

Academic Excellence ◽

Colloidal Silver ◽

Scanning Electron Microscopy Data ◽

Covalent Bonds ◽

Agar Diffusion Test

Chitosan beads with colloidal silver nanoparticles inclued in the polymer matrix have been obtained by the introduction of chitosan into an acidified nanosilver sol. Dual interconnection of drops of the resulting solution was then carried out by ionotropic gelation at the first stage and covalent crosslinking of the polymer matrix with adipic acid at the second stage. The surface morphology of the obtained beads was studied by scanning electron microscopy. Data of Fourier transform IR spectroscopy confirmed the formation of covalent bonds between chitosan and adipic acid. The antibacterial activity of obtained beads against S. aureus and E. coli was evaluated using agar diffusion test. It was shown that the сhitosan beads modified with nanostructured silver exhibited an antibacterial effect against the tested strains, and they can be used as a basis for creating biodegradable wound healing dressings with a prolonged antibacterial effect. chitosan, silver nanoparticles, antibacterial activity, wound dressings This work was supported by the "Russian Academic Excellence Project 5-100". The study was carried out with the financial support of the Russian Foundation for Basic Research in the framework of the Scientific Project no. 18-29-18039.

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