Nitrogen-doped carbon dots with high selectivity for hydrosulfide sensing and their living cells imaging.

Hydrosulfuric acid is an aqueous solution of hydrogen sulfide (HS). At physiological pH, approximately 80% of the total amount of HS exists in the form of monoanionic HS. Because HS is both widely distributed and highly toxic to humans, it is necessary to design an efficient method to detect HS with high sensitivity and selectivity. So, the nitrogen-doped carbon dots (NCDs) with green fluorescence are synthesized using a one-step hydrothermal method. The as-prepared NCDs show it can be effectively used as an indicator for monitoring HS. And the NCD fluorescence intensity exhibits a linear relationship with HS concentration. In addition, NCDs as a probe can be applied for fluorescence imaging in living cells to detect the presence of trace exogenous HS.