Simultaneous determination of Hg(II) and Zn(II) using a GFP inspired chromophore

► A dual-function chemosensor for Hg2+ and Zn2+ was designed and synthesized. ► It is based on the green fluorescent protein (GFP) chromophore. ► It could specifically recognize Zn2+ through an “OFF-ON” fluorescence mechanism.► It also produced a selective visible color change from yellow to pink with Hg2+.