Taking advantage of the aromatic and cross-linking tendency of lignin macromolecules extracted from plants, we present a novel method for their assembly into supracolloidal structures. Specifically, spherical particles with controllable size (∼90 nm to 1 μm) were obtained from water-in-oil (W/O) microemulsions formulated with a mixture of nonionic surfactants and a colloidal dispersion of a low...

Nanometer-sized silver particles were synthesized by using didecylamine dithiocarbamates as the protecting ligands. With control of the initial ligand-metal feed ratios, the core diameter of the resulting particles was found to vary from about 5 to 2.5 nm, as determined by transmission electron microscopic measurements. The core size dispersity was also found to decrease with increasing feed ra...

The mass-transport to a spherical particle in solution is considered in the context of the mechanism of oxygen reduction on silver nanoparticles. For small particles (≤1 μm) the reduction follows a twoproton, two-electron pathway due to the rapid diffusion of the intermediate hydrogen peroxide away from the interface. Above this size threshold the hydrogen peroxide is further reduced to water. ...

The aim of this work was the synthesis of silver nanoparticles using two types of tannins, hydrolysable and condensed, and comparing the properties of incurred colloids. Both tannins are powerful antioxidants (reductants) which differ in their chemical structure as well as certain properties, which influences the formation of silver particles as well as the composition and properties of the res...

Silver particles less than 20 nm in diameter were synthesized by pyrolysis of an ultrasonically atomized spray of highly dilute aqueous silver nitrate solution at temperatures above 650◦C and below the melting point of silver. Feed solution concentration and ultrasound power applied to the atomizer were found to have a significant impact on the particle size of the silver nanoparticles. Average...

Disease-causing microbes that have become resistant to drug therapy are an increasing public health problem. Therefore there is an urgent need to develop new bactericides. Silver nanoparticles are the metal of choice as they hold the promise to kill microbes effectively. Silver nanoparticles take advantages of the oligodynamic effect that silver has on microbes. In this work we have synthesized...

The colloid silver sols with defined average particle size were prepared by means of chemical reduction of silver compound [Ag(SO3)2] 3– by several organic redox systems used as development agents in photography. The average size of the particles varied from 700 to 150 nm in dependence on sulphite concentration in reaction system and reduction compound type.

Silver nanoparticles in the form of silver based chemicals trace back their origin to time immemorial since the dilute forms of silver nitrate were used in place of antibiotics before they dominated the field of medicine. But, it has now become necessary to explore the anti-microbial properties of silver based chemicals again due to the microbes gaining resistance against the wide range of pres...

The influence of silver nanoparticle morphology on the dissolution kinetics in ultrapure water as well as the biological effect on eukaryotic and prokaryotic cells was examined. Silver nanoparticles with different shapes but comparable size and identical surface functionalisation were prepared, i.e. spheres (diameter 40–80 and 120–180 nm; two different samples), platelets (20–60 nm), cubes (140...

Nowadays, green chemistry and its advantages are generating interest of researchers toward ecofriendly biosynthesis of the metallic nanoparticles. In this research, a rapid, simple and green method was developed for the synthesis of silver nanoparticles using aqueous extract of Prangos ferulaceae leaves. The synthesized silver nanoparticles were characterized by UV-Vis spectroscopy, sc...