From Spark to Flame: ROS- and Light-Cascade Activatable NIR-II AIE Probe for Precise Tumor Imaging and...

Area of Science:

• Biomedical Engineering
• Materials Science
• Oncology

Background:

• Photoactivatable theranostic probes are crucial for precision tumor therapy.
• Existing probes have limitations in photoresponsivity, wavelength, and require light for activation, hindering deep tumor diagnosis and effective phototherapy.

Purpose of the Study:

• To develop a novel second near-infrared (NIR-II) aggregation-induced emission (AIE) theranostic probe for enhanced tumor imaging and therapy.
• To overcome limitations of existing probes by designing a dual-activatable cascade system.

Main Methods:

• Designed a dihydroindole-based NIR-II AIE theranostic probe with dual ROS and NIR light-cascade activation.
• Investigated the probe's transformation from TT-DHIn to TT-In upon ROS activation.
• Evaluated the probe's NIR-II fluorescence, ROS generation, and therapeutic efficacy (PDT/PTT) in vitro and in vivo.

Main Results:

• The probe exhibits ROS-triggered transformation to TT-In, enabling NIR-II fluorescence and theranostic capabilities.
• Pre-activated TT-In generates ROS under 660 nm laser irradiation, self-supplementing intratumoral ROS.
• Demonstrated enhanced phototherapeutic efficacy, potent in vitro cytotoxicity, and effective in vivo tumor eradication through cyclic conversion.

Conclusions:

• The dual-activatable cascade strategy effectively integrates ROS responsiveness and photoactivation for precision phototheranostics.
• The developed probe shows promise as a guiding radar for NIR-II imaging-guided therapy.
• This platform offers significant potential for clinical translation in precision oncology.