The Application of Green-Synthesis-Derived Carbon Quantum Dots to Bioimaging and the Analysis of Mercury(II)

摘要： Ginkgo leaves were used as precursors for the hydrothermal synthesis of carbon quantum dots (CQDs), which were subsequently characterized by transmission electron microscopy as well as Fourier-transform infrared, X-ray powder di?raction, and X-ray photoelectron spectroscopy. The prepared CQDs exhibited a ?uorescence quantum yield of 11% and superior water solubility and ?uorescence stability, as well as low cytotoxicities and excellent biocompatibilities with A549 and HeLa cells; these CQDs were also used to bioimage HeLa cells. Moreover, owing to the experimental observation that Hg2+ quenches the ?uorescence of the CQDs in a speci?c and sensitive manner, we developed a method for the detection of Hg2+ using this ?uorescence sensor. The sensor exhibited a linear range for Hg2+ of 0.50–20 μM, with an excellent coe?cient of determination (R2 ? 0.9966) and limit of detection (12.4 nM). In practice, the proposed method was shown to be highly selective and sensitive for the monitoring of Hg2+ in lake water and serum samples.