Abstract

• In this research work, silver nanoparticles were synthesized by using chemical synthesis. In chemical synthesis, trisodium citrate was used as reducing agent. Silver nanoparticles (SNP) were prepared by mixing different volume ratios of 1 % trisodium citrate solution and 1 mM AgNO3 solution (1:10, 2:10 and 3:10 v/v). The existence of SNP in colloidal solutions was confirmed by Tyndall effect and UV-visible spectroscopy. The UV-visible spectrum was revealed the formation of silver nanoparticles by exhibiting the typical surface plasmon absorption maxima at 415 nm. The silver nanoparticles were characterized by modern techniques such as XRD, FT IR, SEM and EDXRF analyses. In XRD analysis, it was found that average crystallite size of SNP powders are in the range of 36.5 nm to 41.7 nm and all the SNP-TSC had the crystalline nature. According to the XRD spectra of all prepared SNP-TSC, there was impurity peaks in the SNP-TSC 2 and SNPTSC 3 but no impurity peaks in the SNP-TSC 1. From the FT IR spectra of all prepared SNP-TSC, it was observed that a strong symmetrical stretch was observed in the range of 1400 cm-1 to 1200 cm-1 where major peaks at 1390-1380 cm-1 which showed the C-H stretching. SEM micrographs of all prepared SNP-TSC showed agglomeration and therefore larger particle size distribution. From EDXRF analyses, the main constituent element in the SNP-TSC1 is Ag (87.177 %). The different types of polyvinyl alcohol (PVA) film were prepared by using different concentrations (1 - 5 % w/v) of PVA to distilled water. The obtained PVA films were designated as PVA-1, PVA-2, PVA-3, PVA-4 and PVA-5. According to the mechanical properties, PVA-3 film was chosen as selected film. The selected PVA-3 film was characterized by SEM, FT IR and TG-DTA analyses. The PVA-SNP composite films were prepared by varying the volume ratios of 3 % (w/v) PVA solution and colloidal SNP-TSC 1 solution. According to the mechanical properties, PVA-SNP-3 was selected and characterized by SEM, FT IR, TG-DTA and EDXRF analyses. The antimicrobial activity of prepared PVA-SNP composite films were investigated using agar well diffusion method.