Mitochondria-Targeted Red-Emission Fluorescent Probe for Ultrafast Detection of H₂S in Food and Its Bioimaging Application

Hydrogen sulfide (H2S) contributes to human health and prolongs the storage time of postharvest fruits and vegetables. At the same time, H2S can cause a negative impact on some foodstuffs and beverages, so an efficient probe to detect H2S is needed. Herein, a fluorescent turn-on responding probe SPy-DNs for H2S detection has been designed and synthesized. SPy-DNs exhibited a red emission (608 nm), large Stokes shift (111 nm), and a detection limit of a nanomolar level (356 nM) in a dimethylformamide/phosphate-buffered saline (DMF/PBS) (1:1, v/v, 10 mM, pH 7.4) solution. SPy-DNs can detect H2S with ultrafast response within 4 s, which is faster than the response of other reported probes. In addition, the applicability of SPy-DNs to detect H2S has been determined in the actual water samples, targeted mitochondria, and imaged H2S in living cells. Moreover, SPy-DNs was successfully used as a tool to judge H2S levels in beer, which indicates that SPy-DNs possesses the advantage of rapid detection of H2S in foodstuffs.