 Carbon-based quantum dots, CQDs, GQDs, CNDs, and CPDs, have been identified as promising agents for photodynamic therapy, PDT. When exposed to light, these nanoparticles can generate highly toxic reactive oxygen species which can be used to kill cancerous or infected cells. Additionally, these particles can also be used to target specific types of cells, making them more effective than traditional PDT agents. This article was authored by Svetlana Yovanovich, Sauron Markovich, Milika Butimer, and others.