Green Synthesis of Silver Nanoparticles Using Plectranthus Amboinicus Leaf Extract for Preparation of CMC/PVA Nanocomposite Film

Abstract

In the present study, the biogenic silver nanoparticles have been synthesized using aqueous leaf extract of Plectranthus amboinicus (PA), which acted as both reducing and stabilizing agents. The PA synthesized silver nanoparticles were blended with carboxymethyl cellulose/polyvinyl alcohol (CMC/PVA) biocomposite. The prepared AgNPs as well as the biogenic AgNPs incorporated CMC/PVA films were investigated using UV-visible spectrophotometry, Fourier-transform infrared spectroscopy (FT-IR), dynamic light scattering (DLS), scanning electron microscope (SEM), and X–ray diffraction (XRD). The DLS results showed that biogenic AgNPs had the average particle size of 65.70 nm with polydispersity index of 0.44. The surface plasmon resonance of AgNPs, which was determined by UV-vis spectrophotometry, showed the value of 410.00 nm. These results therefore confirmed the reduction Ag+ into Ag° and the formation of AgNPs in the medium. The SEM imaging showed that AgNPs was quasi-spherical and monodisperse. The XRD peaks at 33.07°, 44.19°, 64.58° and 77.47° confirmed the crystalline nature and presence of AgNPs. The CMC/PVA films that incorporated with AgNPs displayed best mechanical strength and morphological properties than the pure CMC/PVA film. The film of CMC/PVA-AgNPs exhibited significant antibacterial activities against Bacillus spizizenii, Staphylococcus aureus, Salmonella typhi and Escherichia Coli.