Facile synthesis of biocompatible N, S-doped carbon dots for cell imaging and ion detecting

A facile, simple, effective and green method has been developed to synthesize nitrogen and sulfur co-doped carbon dots (N, S-CDs) from heparin sodium. The as-prepared N, S-CDs possess naked-eye observable blue-green luminescence, good biocompatibility, low toxicity and strong fluorescence in live cell imaging, indicating their great potential to serve as high quality optical imaging probes. Besides, the N, S-CDs can also be used as a competitive fluorescent sensing platform for the detection of Fe3+.