Mechanistic Insights Into NIR‐II AIEgens Boosted Multimodal Phototheranostics

Abstract Exploiting single molecular species synchronously affording powerful second near‐infrared (NIR‐II) fluorescence, superior photoacoustic output, prominent reactive oxygen species generation, and satisfactory photothermal conversion is supremely appealing for phototheranostics, yet remains formidably challenging. In this work, electron donor/π‐bridge engineering is implemented on the basis of 6,7‐di(thiophen‐2‐yl)‐[1,2,5]thiadiazolo[3,4‐ g ]quinoxaline moiety. The optimal molecule, namely TPATO‐TTQ, is demonstrates to exhibit those notable features requested by exceptional phototheranostics, which are systematically elucidated through the depictions of excited‐state energy dissipation pathways and the influence of intramolecular motion on the photophysical properties, with assistances of quantum chemical calculation and molecular dynamic simulation. By utilizing TPATO‐TTQ nanoparticles, unprecedented performance on NIR‐II fluorescence‐photoacoustic‐photothermal trimodal imaging‐navigated type I photodynamic‐photothermal synergistic therapy to orthotopic breast cancer is authenticates by the precise tumor diagnosis and complete tumor ablation.