Hydrothermal synthesis of highly fluorescent nitrogen-doped carbon quantum dots with good biocompatibility and the application for sensing ellagic acid.

Blue emissive nitrogen-doped carbon quantum dots (N-CQDs) with a high quantum yield as high as 84.79% were successfully synthesized via the hydrothermal treatment of citric acid and diethylenetriamine in one pot. The as-prepared N-CQDs displayed excellent stability in high-salt conditions, good photostability, promising the N-CQDs as potential probes for selectively detecting ellagic acid with a linear range of 0.01-50 μM on the basis of inner filter effect. And the hydroponics experiment of gardenia with N-CQDs suggested the good biocompatibility of the N-CQDs, indicating the potential applications in biomedical fields.