Burning windjammer: Multi-rotor engineered photothermal agent with 87% photothermal conversion for antimicrobial treatment.

The evolution of drug-resistant pathogens has significantly diminished the efficacy of antibiotics. Photothermal therapy has appeared as a promising approach for the curing of infectious diseases on account of its high therapeutic efficiency, high controllability, and broad-spectrum bactericidal effect. In this work, by subtly engineering the molecular rotors, a high-performance photothermal agent, 4TPE-TBZ, with a photothermal conversion efficiency up to 87 %, is elaborately designed and fabricated. Mechanism studies disclose that the strategic incorporation of multiple tetraphenylethylene units not only facilitates the molecular rotation but also expands intramolecular motional freedom, thereby effectively enhancing heat generation. In vitro studies demonstrate that 4TPE-TBZ nanoparticles can effectively eradicate the biofilms of both S. aureus and E. coli through the photothermal effect. Subsequent in vivo evaluations conducted on S. aureus-infected abscess and chronic joint inflammation models consistently reveal potent photothermal antibacterial activity alongside marked attenuation of inflammatory responses. This research provides valuable insights for the invention of high-performance photothermal agents that can be applied in effective antibacterial treatments.