Light-Driven ESIPT-Based Anthraquinone Analogues for Synergistic Fluorescent Self-Reporting and Photodynamic Therapy of Malignant Tumors

The intelligent integration of intervention and self-reporting
signals from photosensitizers (PSs) in living organisms remains a
challenge. Herein, we developed two anthraquinone-based PSs (1H-D1
and 1H8H-D1) through polymerization and end-group modification approaches,
which exhibited weak fluorescence due to disruption of the excited-state
intramolecular proton transfer (ESIPT) process. These dimer PSs exhibited
mitochondrial targeting and released monomer natural productsanthraquinone
derivatives (1H and 1H8H) under light irradiation. The released monomers
restored ESIPT fluorescence and effectively generated O2•– via the type-I reaction under continuous
light irradiation, thereby suppressing the growth of tumor cells.
Notably, in vivo experiments showed that 1H-D1 significantly inhibited
tumor growth (Vlight/Vcontrol ≈ 0.24). At the same time, the fluorescence
intensity of 1H-D1 was greatly enhanced, providing excellent guidance
on the treatment outcome. It can be seen that this dual-effect synergy
strategy offers a promising approach for designing natural product-based
self-reporting PSs with enhanced therapeutic and diagnostic capabilities.