Highly fluorescent N doped C-dots as sensor for selective detection of Hg in beverages.

In this work, nitrogen doped carbon dots (NCDs) were synthesized through one step hydrothermal reaction using citric acid and ethylenediamine as precursors. The prepared NCDs exhibit high quantum yield of 67.4%, good stability, excellent selectivity and sensitivity. It was found that the NCDs have potential as a fluorescence sensor for the detection of Hg. Under optimal conditions, good linearity between the change in NCDs fluorescence intensity and Hg concentration was obtained in the range of 0.3 to 2.0 μM with a detection limit at 0.24 μM. The possible detection mechanism was static quenching of NCDs by Hg. The established method was successfully applied to the determination of Hg in beverage samples. The results indicated that the NCDs-based sensor has potential for detection of Hg in real beverage sample.