A Facile Strategy of Boosting Photothermal Conversion Efficiency through States Transformation for Cancer Therapy

Improving photothermal conversion efficiency (PCE) is critical to facilitate therapeutic performance during photothermal therapy (PTT). However, current strategies of prompting PCE always involve complex synthesis or modification of photothermal agents, thereby significantly inhibiting the practical applications and fundamental understanding of photothermal conversion. We herein present a facile strategy of transforming photothermal agents from aggregated state to dispersed state for boosting PCE. Compared to aggregated state, photothermal agents could rotate freely in dispersed state, allowing for an efficient non-radiative dissipation by formation of highly twisted intramolecular charge transfer (TICT) state. As the molecular motions are completely liberated in this strategy, the PCE enhancement is more remarkable than common methods of supporting molecular motions in aggregates. Noteworthy, this state transformation could be achieved in virtue of a releasing process from nanoparticles in lysosome of cancer cells, demonstrating a distinct photothermal therapeutic performance for cancer ablation. We hope this strategy of transforming state to boost PCE would be a new platform for practical applications of PTT technique.