Investigating Antibacterial Effects of Nano-Ag/titanium dioxide on Polylactic Acid Nanocomposites Produced Using Extrusion Method
نویسندگان
1 Department of Food Hygiene, Science and Research Branch, Islamic Azad University, Tehran, Iran.
2 Department of Food Science and Technology, Science and Research Branch, Islamic Azad University, Tehran, Iran.
3 Department of Food Hygiene, Science and Research Branch, Islamic Azad University, Tehran, Iran.
4 Department of Food Hygiene, Science and Research Branch, Islamic Azad University, Tehran, Iran.
doi
10.22037/afb.v11i1.45932چکیده
Background and Objective: Biodegradable polymers generally do not include antibacterial characteristics. This study investigated effects of various concentrations of nano-titanium dioxide containing silver on polylactic acid nanocomposites for their microscopic, chemical, roughness of the coatings and antibacterial characteristics against Staphylococcus aureus and Escherichia coli. Material and Methods: Nanometric structure of the coatings was assessed through multiple steps. First, films containing 0.5, 1 and 3% wt% concentrations were produced using extrusion method and then analyzed and compared using scanning electron microscope and energy dispersive spectroscopy. Then, Fourier transform infrared spectroscopy and atomic force microscope were used to investigate functional groups, types of bonds, peak intensity variations and roughness characteristics of the films. Moreover, antimicrobial effects of the coatings was assessed on Staphylococcus aureus and Escherichia coli. Results and Conclusion: Results of the scanning electron microscope indicated that the accumulation of nanoparticles in the films increased with increasing concentration of the nanoparticles. This increase affected energy dispersive spectroscopy, resulting in higher levels of titanium and silver nanoparticles. Fourier transform infrared spectroscopy revealed changes in intensity and position of the peaks due to the presence of nanoparticles. Bacterial growth assessments demonstrated that addition of nano-titanium dioxide containing silver to polylactic acid significantly decreased the growth of Staphylococcus aureus and Escherichia coli bacteria (p < 0.05). Based on the results, coatings containing 3 wt% of nano-titanium dioxide with silver showed the greatest decrease in bacterial growth. Conflict of interest: The authors declare no conflict of interest.
