Advances in cancer photodynamic therapy

Photodynamic therapy(PDT)is a minimal invasive therapy that have been clinically approved for the cancer treatment with selective cell toxicity. When activated by appropriate wavelength of light, photosensitizers transfer the absorbed photon energy to the surrounding molecular oxygen to generate reactive oxygen species, which result in cell death, vessel damage and immune activation of tumor site. This paper summarize the main challenges and recent solutions for PDT application, such as the low tissue penetration of light, toxicity induced by nonspecific accumulation of skin and poor PDT effect of hypoxia tumor.