FIGURE 7.

Schematic illustration of the light-responsive SPNpd for synergistic cancer therapy. The nano-prodrug is assembled from an amphiphilic semiconducting brush polymer grafted with chemo drug side chains through a hypoxia-cleavable linker. It has three critical units: the light-responsive photodynamic SPN core, hypoxia-cleavable linker and the chemotherapeutic drug, a bromoisophosphoramide mustard intermediate (IPM-Br). Upon the photoirradiation at 808 nm, this organic photodynamic nano-prodrug (SPNpd) can specifically release the chemodrug under photoirradiation-promoted hypoxia tumor microenvironment to exert synergetic PDT and chemotherapy. Reprinted from Dong Cui, Jiaguo Huang, Xu Zhen, et al. Semiconducting Polymer Nano-prodrug for Hypoxia-activated Synergetic Photodynamic Cancer therapy. Angew Chem Int Ed Engl 2019;58(18):5920–24. With permission from reference (Cui et al., 2019). SPNpd, semiconducting polymer nanoprodrug; SPN, semiconducting polymer nanoparticle; PDT, photodynamic therapy.