A Dual‐Functional Fluorescent Probe With Long‐Wavelength Emission for Detecting H ₂ S in Living Cells and CN ⁻ in Food Samples

In this study, a novel difunctional fluorescent probe DDI , featuring long‐wavelength emission capabilities, was meticulously designed and synthesized to enable the concurrent detection of hydrogen sulfide (H 2 S) and cyanide ions (CN − ). Probe DDI recognizes H 2 S with fluorescence “Off‐On” responding in DMF/HEPES (2/8, v/v, pH = 7.4) solution and can image H 2 S in living cells. In addition, DDI detects CN − by the naked eye in DMF/PBS (1/1, v/v, pH = 7.4) solution, and the color of DDI changes from purple to colorless. Moreover, Probe DDI can be prepared into a filter paper strip for rapid qualitative detection CN − , and can be used to detect CN − in germinated potatoes.