Structure and antibacterial activity of PLA-based biodegradable nanocomposite coatings by electron beam deposition from active gas phase

Abstract

The synthesized poly(lactic acid)-based (PLA-based) biodegradable nanocomposite coatings with antibacterial properties were prepared from active gas phase generated by low-energy electron beam dispersion of the powder mixture of PLA and antibacterial components (Norfloxacin and silver nitrate, respectively) in vacuum. The molecular structure, morphology, optical property and chemical states of PLA-based coatings were investigated by ATR-FTIR, Uv–Vis, TEM and XPS. The analyses of ATR-FTIR spectra confirm the formation of polymer and the doped antibacterial components and show the interaction between them. XPS data show that the Ag nanoparticles are of metallic nature in the case of PLA-based nanocomposite coatings containing silver. The antibacterial activity of PLA-based coatings deposited on different substrates was tested against E. coli ATCC 25922 and S. aureus ATCC 12600 using the agar diffusion method on the solid LB agar medium. The influence of substrates on their antimicrobial behavior was stated.