Investigation of physical, mechanical and antibacterial properties of nanobiocomposite films based on starch containing metallic nanoparticles such as silver, zinc oxide and cooper oxide

In this research the starch-based nanobiocomposite films using zinc oxide, copper oxide and silver nanoparticles prepared by solution casting method and then UV-Vis spectra, scanning electron microscopy, physical and mechanical properties of these films were analyzed. Water vapor permeability (WVP) test and the water solubility of the nanobiocomposite films made from different percentage presents of nanomaterials showed the nanobiocomposite films with 3 percent by weight nano zinc oxide has the greatest reduction in vapor permeability and the highest water solubility due to well dispersion of these nanoparticles compare to copper oxide and silver nanoparticles in polymer matrix. UV-Vis data showed the films with zinc oxide nanoparticles absorbed the greatest amount of UV wavelength compare to other two nanoparticles. With respect to the antimicrobial analyzes on the samples, it observed the nanobiocomposite films consist of silver nanoparticles and the copper nanoparticles showed the highest sensitivity for Escherichia coli and Staphylococcus aureus bacteria, respectively. The antimicrobial property of the films with 2 percent by weight silver nanoparticles were 94 percent for Escherichia coli bacteria and 83 percent for Staphylococcus aureus. Also, the result from mechanical strength analysis showed the starch-zinc oxide nanobiocomposite films have better tensile strength compare to the starch-silver and copper oxide nanoparticles.