Fabrication and In Vitro Evaluation of PVA/CeO2 Nanocomposite Films as Antibacterial Agents

Abstract

Bacterial infections continue to be a significant global health issue, worsened by the rise of antimicrobial resistance and the limited efficacy of conventional treatments. While cerium dioxide nanoparticles have the ability to exterminate bacteria, their performance is hindered by their lack of stability in colloidal form and tendency to aggregate quickly, hindering their control. Current manufacturing techniques are complex, necessitating a clean and environmentally friendly method to produce nanoparticles that are highly stable and evenly distributed, thereby improving their antibacterial properties. Thus, this research successfully created and analyzed Polyvinyl alcohol (PVA) and cerium dioxide (CeO2) nanocomposite films through casting, integrating CeO2 nanoparticles at varying concentrations (0.3 at%, 0.6 at%, and 0.9 at%). The average crystallite sizes of the resulting nanocomposites ranged from approximately 18.14 to 44.58 nm. Analysis using XRD and EDS demonstrated that all synthesized nanocomposites had a polycrystalline structure with excellent crystallinity. Enhanced absorbance in the UV range was noted due to the deposition of CeO2 on the PVA surface. The antibacterial findings indicated that the inclusion of CeO2, particularly at concentrations of 0.3 at% and 0.6 at%, which  exhibited good activity against S. aureus, while it decreased  at 0.9 at% CeO2 due to clumping and reduced surface area for interaction with bacterial cells. Furthermore, the activity was only observed at concentration of 0.6 at % against E. coli. FE-SEM revealed agglomerated nearly spherical nanoparticles with increasing CeO2 content up to 0.9%. This illustrated the successful integration of cerium dioxide nanoparticles into the polymer matrix, as confirmed by the presence of absorption bands corresponding to the monoclinic phase of Nano-CeO2 in the FTIR results.