LAUSR

Living drug delivery system has been proposed as new concept materials because it is able to communicate with biological system, sense subtle changes in body microenvironment caused by disease, and then make rapid response to cure in the early stage of disease. Herein, taking full advantage of the tumor hypoxia physiology and successive effects of photodynamic therapy (PDT), we designed a new living delivery system via combining the PDT and hypoxia-responsive chemotherapy, abbreviated as Ce6-PEG-Azo-PCL. Then, according to the fact that oxygen can be converted into reactive oxygen species during irradiation of the photosensitizer, tumor cells could be killed after the poly(ethylene glycol) (PEG) conjugated photosensitizer chlorine e6 was irradiated at the tumor site. What is more, the continuous consumption of oxygen could further amplify the hypoxia condition of tumor and trigger the disassembly of hypoxia-responsive azobenzene bridges at the tumor site to release loaded chemotherapeutics drugs doxorubicin. The ongoing collaboration with PDT and hypoxia-responsive chemotherapy provided an integrated therapeutic effect in vitro and in vivo to suppress tumor growth.