 A platinum nanosyme, point NP, loaded reactive oxygen species, ROS, responsive prodrugged nanoparticle, CPTTKHPPH slash point NP, is created to overcome the limitations of chemotherapy and photodynamic synergistic therapy in cancer treatment. The ROS-responsive prodrugged consists of a thio-ketal bond linked with camptothacin, CPT, and photosensitizer 2, 1-hexaloxiephyl, 2-devinyl pyrophio 4-by-day, HPPH. The point NP in CPTTKHPPH slash point NP can efficiently catalyze the decomposition of hydrogen peroxide, H2O2, into oxygen to relieve hypoxia. The production of oxygen can satisfy the consumption of HPPH under 660 nm laser irradiation, to attain the on-demand release of CPT and ensure enhanced photodynamic therapy. As a tumor diagnosis agent, the results of photoacoustic imaging and fluorescence imaging for CPTTKHPPH slash point NP exhibit, desirable long circulation and enhanced in vivo targeting. CPTTKHPPH slash point NP effectively inhibit tumor proliferation and growth in vitro and in vivo, making it a new cancer theranostic agent that can further promote the research of chemo-photodynamic synergistic cancer therapy. This article was authored by Nghao, Yuwen Chen, Xinlong He, and others. We are article.tv, links in the description below.