Highly durable photocatalytic titanium suboxide–polymer nanocomposite films with visible light-triggered antibiofilm activity

Bacterial biofilms on medical devices may result in infections with significant societal burden. One drug-free strategy against biofilms is photocatalysis, in which a semiconducting coating is applied on the medical device and irradiated with light to generate reactive oxygen species providing an on-demand disinfection approach. However, most photocatalytic materials are active in the harmful UV range rendering them unsuitable for biomedical applications. Furthermore, the main manufacturing bottleneck today for antibiofilm coatings is their poor durability. To address these challenges, here we produced silver/titanium-suboxide nanoparticles that are photocatalytically active in the visible-light range. Moreover, we directly deposited the nanoparticles as porous coatings on substrates in situ during their aerosol synthesis. To enhance their durability, we infused the fabricated porous coatings with a polymer solution barely covering the photocatalytic particle film, resulting in the formation of polymer nanocomposite coatings. The optimized polymer nanocomposite films exhibit several cycles of triggered, on-demand biofilm eradication activity under short visible light illumination of 15–90 min with no significant intrinsic cytotoxicity to mammalian cells. The developed films can be considered as a suitable coating material for medical devices, such as catheters, ventilators, wound meshes, and others, that may require repeated disinfection during use.