Photoactivable alizarin and eugenol-based materials for antibacterial applications

We report herein the design of a new visible-light epoxy-based alizarin photosensitizer (AE) iodonium salt (Iod) for cationic polymerization (CP) epoxidized eugenol monomers under irradiation. The combination AE and Iod demonstrates highly efficient photoinitiating properties air. As highlighted by fluorescence, laser flash photolysis (LFP) electron paramagnetic resonance spin-trapping (ESR ST) experiments, acts as an donating molecule, reacts with light exposure through its excited singlet triplet states via photoinduced transfer reaction, producing thus protonic acids, H+, able to initiate CP. Also, we demonstrate EPR ST that addition diepoxy monomer may lead formation reactive radical species which be oxidized form species. Thus, bio-based photoactivable materials were designed photopolymerization use alizarin-based derived monomers. By tuning weight proportion epoxy (mono- (EE) di-epoxidized (EdE) eugenol), can modulate thermal mechanical resulting materials. AE-based have demonstrated two interesting properties: first, presence EE in polymer network has considerably decreased number colony forming units (CFUs) at surface whatever bacterial strains used, these samples they produce, irradiation, oxygen, biocide agent against bacteria. Interestingly, irradiation AE/Iod/EE(50)/EdE(50) tremendous decrease E. coli S. aureus CFUs their surface. A reduction 100% adhesion is observed upon exposure.