Photodynamic Therapy of Tumors In article number 2205440, Zhiyang Liu, Quan Li, and co-workers exploit the hypoxic properties solid tumors to construct a hypoxia-responsive photosensitizer. When non-fluorescent photosensitizer enters tumors, it is reduced by overexpressed azoreductase generate fluorescent with aggregation-induced emission property, which can realize fluorescence-activatable ima...