Oxygen self-sufficient photodynamic therapy

Photodynamic therapy (PDT) is a non-invasive treatment for various cancers and non-malignant diseases. Despite its clinical promise, one of the major drawbacks of some PDT agents is their oxygen-dependent nature. This limits their efficiency in hypoxic solid tumors. Recent advances in nanotechnology and nanomedicine have led to the development of oxygen self-sufficient materials as PDT agents to overcome this problem. The key factors in this area are discussed in this review. This includes why tumors tend to be hypoxic, the relationship between PDT and oxygen, and the challenges and opportunities of PDT in hypoxia. In particular, recent advances in the design of oxygen self-sufficient nanomaterials to overcome hypoxia and achieve effective PDT in solid tumors are highlighted.