Aminoquinoline-based fluorescent probe for detection of Cu2 + and hydrogen sulfide

•The probe DOQED selectively binds the Cu2+ to quench the intrinsic fluorescence.•The X-ray crystallography of DOQED-Cu2+ complex confirms the binding mode.•The S2– replaces the Cu2+ from DOQED-Cu2+ and recovers the quenched fluorescence.•DOQED has potential applications in detecting Cu2+ and S2– in biological samples.

Diethyl 2,2′-(2-oxo-2-(quinolin-8-ylamino)ethylazanediyl) diacetate (DOQED), an aminoquinoline-based fluorescent probe, was synthesized, and successfully applied in detection of Cu2 + and S2 − in an aqueous buffered solution. The emission signal of DOQED was selectively quenched by Cu2 +, and was exclusively recovered by subsequent addition of S2 −. The formation of a [Cu(DOQED)]2 + complex was confirmed by X-ray crystallography.

Graphical abstractThe aminoquinoline-based probe DOQED displays good selectivity and sensitivity in detection of Cu2+ and S2– in an aqueous solution. The emission signal of DOQED was selectively quenched by Cu2+, and exclusively recovered by the addition of S2–. The formation of a Cu-DOQED complex was confirmed by X-ray crystallography.Figure optionsDownload full-size imageDownload as PowerPoint slide