Advance of Near‐Infrared Emissive Carbon Dots in Diagnosis and Therapy: Synthesis, Luminescence, and Application

Abstract

Carbon dots (CDs) with good optical properties, biocompatibility, easy functionalization, and small size have attracted more and more attention and laid a good foundation for their applications in the biomedicine field. CDs emitted in near‐infrared regions (NIR‐CDs) can achieve high penetration depth imaging and produce high cytotoxic substance for disease treatment. Therefore, NIR‐CDs are promising materials to realize high‐quality imaging‐guided diagnostic and therapeutic integration. This review first introduces the current mainstream synthesis methods of NIR‐CDs by “top–down” and “bottom–up”. Second, the luminescence modes of NIR‐CDs are introduced, and the luminescence mechanisms based on carbon core state, surface state, molecular state, and crosslinking enhanced emission are summarized. Third, the applications and principles of NIR‐CDs in imaging, drug delivery, and non‐invasive therapeutics are introduced from a view of diagnosis and therapy. Finally, their prospects and challenges in biomedical and biotechnological applications are outlined.