Carbon dots derived from organic drug molecules with improved therapeutic effects and new functions

Carbon dots (CDs) are new types of fluorescent nanomaterials with particle diameters of 1∼10 nm and have excellent photoluminescence (PL) properties, good biocompatibility, simple preparation methods and numerous raw materials; consequently, they are promising in the biomedical field. In recent years, to overcome drug resistance and toxic side effects of traditional organic drugs, the synthesis of CDs from drug molecules has become an effective strategy, which produces CDs with the same therapeutic effects as the raw drugs and even possessing new properties. At present, many CDs derived from organic drugs have been developed, which can be classified according to their sources such as antibiotics, anti-inflammatory drugs, and guanidine drugs. This article focuses on the progress of the above-mentioned drug-derived CDs compared with their drug precursors in terms of therapeutic efficacy, enhanced performance and new additional functions, with special attention to the structure-activity relationship between the drug precursors and the CD-based therapeutic agents. It demonstrates the feasibility of designing new drug-derived CDs for clinical applications, summarizes the shortcomings and research gaps of the existing work, and provides a reference for related work in the future.