Ag Thin Films from Pelargonium Zonale Leaves via Green Chemistry

Ag thin films were successfully produced via a green chemistry method from silver nanoparticles (AgNPs) obtained from reacting an extract of Pelargonium Zonale leaves with silver nitrate. The ions of silver nitrate were reduced to silver atoms by reducing stabilizer-capping compounds contained in the extract of Pelargonium Zonale leaves. The obtained atoms nucleate in small clusters that grew into nanoparticles and finally, they formed a homogeneous silver thin film on a glass substrate. The nanostructured thin films obtained were characterized by profilometry, X Ray Diffraction, Atomic Force Electronic Microscopy, UV-Vis, and Transmission Electron Microscopy.

Antibacterial Efficacy of Silver or Arsenic Doped Polymer Composites Against Several Kinds of Bacteria

Structure and several properties of AgNO3 and As2O3 doped polymer composites have been investigated, including their antibacterial activity against E. coli, S. aureus, C. albicans and S. epidermidis. New silver or arsenic doped polymer composites have been characterized by an X-ray diffraction (XRD), a scanning electron microscopy combined with an energy dispersive X-ray spectroscopy (SEM/EDS) and ion release studies. The antibacterial evaluation of each of the composite samples was conducted using S. aureus in the liquid broth culture, with 10, 20 and 30 % of liquid extract added to the bacterial culture. Control S. aureus stocks were used for comparison at each time period and were recorded at 100 % at each time period. For samples with the PLA plasticizer the bacterial viability was significantly reduced for each composition containing Ag/As and was similar for each dosage concentration.

Synthesis of Antibacterially ActiveSilver Nanoparticles by Galvanic Replacement on Magnesium in Solutions of Sodium Polyacrylate in an Ultrasound

“Green” synthesis of silver nanoparticles (AgNPs) by a galvanic replacement (GR) on magnesium in solutions of sodium polyacrylate (NaPA) under ultrasound (42 kHz) is reported. The mechanism of combined action of GR and ultrasound on the formation of nanoparticles is proposed. Synthesized solutions of AgNPs are characterized by an absorption maximum at 410 nm, the value of which does not depend on the concentrations of precursors (AgNO3 and NaPA) and the duration of the process. The dimensions of nanoparticles that have a spherical shape do not exceed 30 nm. With increasing concentration of surfactant, there is a tendency to decrease in size. The rate of synthesis of AgNPs increases almost in proportion to the concentration of AgNO3 in the solution, while the effect of NaPA concentration is negligible. The synthesized nanoparticles efficiently demonstrated a bactericide effect on Escherichia coli and Staphylococcus aureus.