N-dots as a photoluminescent probe for the rapid and selective detection of Hg2+ and Ag+ in aqueous solution

Abstract

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 Hg²⁺ and Ag⁺ in aqueous solutions. Distinguishing between Hg²⁺ 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 Hg²⁺ and Ag⁺ with N-dots.