In this thesis, ZnO and their hybrid with Ag (ZnO@Ag) were used for preparation of blend nanocomposites (NCs) based on chitosan (CS) and Tragacanth gum (TG). These NCs were characterized with various techniques such as Field Emission Scanning Electron Microscopy (FE-SEM), X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FT-IR) and Energy Dispersive X-ray diffraction (EDX). The FE-SEM images shows a spherical morphology for ZnO , Ag and ZnO@Ag hybrid. According to TEM images and their histogram, the average particle size for Ag was 19 nm and for ZnO@Ag hybrid (1:0.500) was 14 nm. This decreasment is caused by better dispersion of in hybrid. The NC films based on ZnO (CS-TG/ZnO) were made by different percentage of ZnO (2, 5 and 8) wt% of polymer blend. For fabrication of CS-TG/ZnO@Ag NC films, different percentage of ZnO@Ag hybrid with ratio of ZnO: Ag (1:0.125, 1:0.250 and 1:0.500) 8 wt% of total polymer blend were added to the CS-TG. The obtained NCs were studied with FE-SEM, TEM, XRD and FT-IR. According to FE-SEM data, with addition of into the CS-TG matrix the surface morphology of these NCs were changed to a rough form with good dispersion. TEM images showed a uniform dispersion of ZnO into the CS-TG/ZnO NC. The average particle size of ZnO into the CS-TG/ZnO 8 wt% NC was 27 nm according to its histogram. These NC samples were immersed in simulated body fluid (SBF) for 27 days for surveying their Bioactivity and mineralization of hydroxyapatite (HA). The CS-TG, CS-TG/ZnO 2 wt% and CS-TG/ZnO@Ag (1:0.500) 8 wt% showed a most significant of hydroxyapatite on their surface according to EDX analysis. The FE-SEM images show a tiny island of HA on the surface of NCs, which confirmed the bioactive ability of NCs. The antibacterial survey shows that, the NCs contain ZnO@Ag hybrid showed more antibacterial activity than NCs contain ZnO against Staphylococus aureus and Escherchia coli bacteria.
