LAUSR

Abstract This article was allocated to synthesize stable silver nanoparticles, Ag-NPs samples. In addition, to study the microstructural characteristics of these samples and their relationship with the antibacterial activities. Ag-NPs samples have been incorporated utilizing the chemical reduction approach without using a capping or stabilizing agents by the diminishment of silver nitrate in nearness of tannic acid, at different concentrations from the metal precursors. The selected concentrations were varied from 0.02 M to 1.0 M, where the ratio of the chemical metal precursors, (Silver nitrate) has been taken to be 1:1 for all samples. Microstructural properties of the prepared silver nanoparticles have been described and affirmed by utilizing X-Ray diffraction, XRD, transmission electron Microscope, selected area electron diffraction and particle size analysis examination by the dynamic light diffusing. The analysis of XRD has exhibited that all obtained Ag-NPs samples have face center cubic structures with the preferred orientation in 〈111〉 direction. The mean particle sizes of the synthesized samples of Ag-NPs were ranged between 33.3 nm and 69.8 nm, when the concentricity of the precursors increased from 0.02 M to 1.00 M, respectively. Antimicrobial activity of silver nanoparticles of concentrations 30 mg/L, 60 mg/L, 100 mg/L against bacterial strains (Escherichia coli, bacillus subtilis) and fungal strains (Candida albicans) were investigated and discussed. Ag-NPs showed more inhibition activity for bacterial strains than the fungal strains. While, bacillus subtilis and Candida albicans showed high sensitivity against Ag-NPs.