Nowhere to run: oligo (p-phenylene vinylene) kills oral intracellular bacteria photodynamically

Bacterial infections pose a severe threat to human health due to the exacerbation of antibiotic resistance and intracellular bacterial infections. Research suggests that oligo(p-phenylene vinylene) (OPV), commonly employed in the manufacture of organic solar batteries, can help address this issue. This study demonstrates the ability of OPV to target and sterilize intracellular Porphyromonas gingivalis and methicillin-resistant Staphylococcus aureus (MRSA) photodynamically. Most notably, OPV specifically targets bacteria without affecting healthy cells under dark conditions. Its chemical composition includes a conjugated backbone and ionic imidazole side chains, which allow OPV to bind to cell membranes. Furthermore, dental blue light curing lamps may excite OPV. Compared with antibiotics and traditional photosensitizers, OPV proves to be a potentially superior solution to eradicate intracellular microbial infections, both in fundamental research and clinical applications. This paper introduces OPV, an organic semiconductor material, as a novel photosensitizer to kill intracellular bacteria that are infectious and antibiotic-resistant. It explains how OPV binds to bacterial membranes and produces reactive oxygen species by blue light, guiding photodynamic therapy design. It proves the excellent antibacterial effect of OPV against Porphyromonas gingivalis and MRSA in vitro and in vivo, without damaging normal cells or tissues, indicating good biocompatibility and safety. It also shows that OPV can be excited by dental blue light curing lamps, facilitating clinical applications.