Dual Molecular Design toward a Lysosome-Tagged AIEgen and Heavy-Atom-Free Photosensitizers for Hypoxic Cancer Photodynamic Therapy.

To date, a large number of photosensitizers (PS) have introduced heavy atoms to improve the ISC process and 1 O 2 generation. However, they often show low efficiency in hypoxic conditions, aggregate states, and turn-off PDT in the dark. Besides that, the toxicity of heavy metals is also concerned. Therefore, we developed lysosome-targeted heavy-metal-free PS ( 3S and 4S ) based on thionated naphthalimide for hypoxic cancer photodynamic therapy (PDT), not only under white light but also in the dark via thermal-induced 1 O 2 generation. AIEgen ( 3O and 4O ) were prepared for studying the PDT action of PSs ( 3S and 4S ) in lysosome and aggregate state. We also examined the photophysical properties of AIEgen ( 3O and 4O ) and PS ( 3S and 4S ) by UV-vis absorption, fluorescent emission spectra, and theoretical calculations.