Photosensitizers for Two‐Photon Excited Photodynamic Therapy

Abstract

Abstract Photodynamic therapy (PDT) is a noninvasive protocol for the treatment of various cancers and nonmalignant diseases. Light, oxygen, and photosensitizer (PS) are the essential three elements in a typical PDT process. Currently, there are two major barriers limiting the further development of PDT. One issue is limited tissue penetration, and the other is the lack of high‐performance PSs. Therefore, the newly emerging two‐photon excited PDT (2PE‐PDT) has attracted considerable attention in recent years due to its advantages such as a higher spatial resolution and a greater penetration depth. In this review, focus is on (i) the principle of 2PE‐PDT, (ii) the progression of PSs for 2PE‐PDT, and (iii) the potential indications and future directions in this field.