Fabrication, Characterization, and Antibacterial Performance of Polyvinyl Alcohol (PVA)-Zinc Oxide (ZnO) Thin Films...

Polyvinyl alcohol (PVA) is a well-known packaging material; however, its major drawback is the lack of inherent antibacterial properties, which are essential for preventing food spoilage. In the present work, we developed a method to enhance the antibacterial properties of PVA thin films by incorporating nanoparticles (NPs) into the films. Undoped and cobalt (Co)-doped zinc oxide (ZnO) nanoparticles were synthesized using PVA as a capping agent. The nanoparticles were prepared via chemical precipitation and microwave-assisted methods, and characterized using UV-Visible spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and X-Ray Diffraction (XRD). The crystallite sizes of the undoped and Co-doped ZnO were found to be 30.6 nm and 22.9 nm, respectively. SEM imaging revealed variations in surface morphology with different concentrations of PVA capping. PVA thin films containing 0.1%, 0.2%, and 0.3% of the synthesized nanoparticles were prepared and evaluated for their antimicrobial activity against Gram-negative bacteria Escherichia coli (MTCC 1559) and Gram-positive bacteria Enterococcus faecalis (MTCC 439). The results demonstrated that the incorporation of nanoparticles significantly enhanced the antibacterial activity of the PVA films.