N-dots as a photoluminescent probe for the rapid and selective detection of Hg and Ag in aqueous solution.

Green fluorescent nitrogen-rich quantum dots (N-dots) have been synthesized under mild conditions (50 °C in methanol) and applied as a turn-off chemosensor for the rapid and selective detection of Hg and Ag in aqueous solutions. Distinguishing between Hg and Ag was also successfully achieved simply through the addition of ethylene diamine tetraacetic acid (EDTA). These N-dots-Hg and N-dots-Ag could also be used as turn-on chemosensors for biothiols through their binding competition for Hg and Ag with N-dots.