Robust Antibacterial Activity of Xanthan-Gum-Stabilized and Patterned CeO2-x-TiO2 Antifog Films

Increased occurrence of antimicrobial resistance leads to a huge burden on patients, the healthcare system, and society worldwide. Developing antimicrobial materials through doping rareearth elements is a new strategy to overcome this challenge. To this end, we design antibacterial films containing CeO2-x-TiO2, xanthan gum, poly(acrylic acid), and hyaluronic acid. CeO2-x-TiO2 inks are additionally integrated into a hexagonal grid for prominent transparency. Such design yields not only an antibacterial efficacy of similar to 100% toward Staphylococcus aureus and Escherichia coli but also excellent antifog performance for 72 h in a 100% humidity atmosphere. Moreover, FluidFM is employed to understand the interaction in-depth between bacteria and materials. We further reveal that reactive oxygen species (ROS) are crucial for the bactericidal activity of E. coli through fluorescent spectroscopic analysis and SEM imaging. We meanwhile confirm that Ce3+ ions are involved in the stripping phosphate groups, damaging the cell membrane of S. aureus. Therefore, the hexagonal mesh and xanthan-gum cross-linking chains act as a reservoir for ROS and Ce3+ ions, realizing a long-lasting antibacterial function. We hence develop an antibacterial and antifog dual functional material that has the potential for a broad application in display devices, medical devices, food packaging, and wearable electronics.

Automated summary

The increased occurrence of antimicrobial resistance poses a significant burden on patients, the healthcare system, and society. This study proposes a new strategy of developing antimicrobial materials by doping rare earth elements. An antibacterial film containing CeO2-x-TiO2, xanthan gum, poly(acrylic acid), and hyaluronic acid is designed, with CeO2-x-TiO2 integrated into a hexagonal grid for transparency. The antibacterial film demonstrates high efficacy against Staphylococcus aureus and Escherichia coli, as well as excellent antifog performance. The study also reveals the involvement of reactive oxygen species (ROS) and Ce3+ ions in the antibacterial activity.