186 / 2024-06-15 09:57:21

Construction of NIR-II AIEgens Based on Benzo[c]thiophene Units and Its Applications in Disease Theranostics

aggregation-induced emission; NIR-II fluorescence imaging

The near-infrared II (NIR-II, 1000−1700 nm) biological imaging window shows excellent performance in biological imaging due to its low degree of light scattering and small biological autofluorescence background interference.  However, traditonal fluorophores may encounter the drawbacks of aggregation-induced fluorescence quenching (ACQ).  

  Fortunately, Tang and coworkers coined the concept of aggregation-induced emission (AIE) in 2001. AIE molecules with twisted structures can well solve the problem of insufficient fluorescence brightness caused by π-π stacking in the aggregated state.  In addition, due to the existence of the multirotor unit, the molecules can still maintain local rotation/vibration in the aggregated state, thereby generating thermal energy for photothermal treatment.  As a sterically hindered, electron-rich electron donor/π-bridge, benzo[c]thiophene is beneficial to the construction of NIR-II AIE luminogens. Through systematic research, our team used benzo[c]thiophene to construct a series of NIR-II AIEs for the first time, showing excellent optical diagnostic and therapeutic properties, and successfully applied them in anti-tumor and antibacterial applications.