Self-assembly strategies of organic small-molecule photosensitizers for photodynamic therapy

In recent years, the use of organic small-molecule photosensitizers, which make up the majority of photosensitizers, has significantly enhanced the therapeutic outcomes of various diseases including cancer and antibacterial treatment because of their benefits of biocompatibility, minimal invasiveness, minimal toxicity, non-drug-resistance, and facile molecular tailoring. However, many organic small-molecule photosensitizers suffer from poor photostability, targeting, and controllability, which limit the bench-to-bedside transformation. Self-assembly strategies could effectively handle these problems and difficulties. This review provides an overview of the self-assembly strategies of organic small-molecule photosensitizers for photodynamic therapy in recent years, including molecular design and modification, stimuli-responsive, photosensitizer-drug conjugate, metal coordination, and others. The article also discussed the prospects and challenges of organic small-molecule photosensitizers in clinical applications.