Quinizarin-based photoactive porous polymers from emulsion templates: Monoliths versus membranes in photobactericidal applications

Abstract

The increasing challenge of antimicrobial resistance and the persistent threat of infectious diseases are strong incentives for development of novel materials that effectively and sustainably combat bacterial proliferation. Macroporous materials contribute to this endeavor, but the reported antibacterial porous polymers rely on the release of antibacterial agents, which carries the risk that their efficacy will diminish over time. This work reports a facile synthesis by emulsion templating polymerization of innovative photo-bactericidal macroporous polymers functionalized by a quinizarin photosensitizer that generates antibacterial reactive oxygen species under visible light. In brief, a monomethacrylated quinizarin (QMA) derivative, known for its ability to generate bactericidal singlet oxygen upon visible light irradiation, is copolymerized with a bio-based acrylated epoxidized soybean oil (AESO) under high internal phase emulsion (HIPE) conditions, resulting in 3D-interconnected quinizarin-functionalized macroporous monoliths. The QMA-functionalized polyHIPEs are also structured into membranes by photocuring thin layers of HIPEs to increase their external surface and promote interaction with light. Photobleaching tests show the ability of these materials to generate bactericidal singlet oxygen. Antibacterial tests also demonstrate the sustained antibacterial efficacy of the QMA-based porous membranes, providing a promising avenue for the development of next-generation antibacterial materials.