A 3,5-dinitropyridin-2yl Substituted Flavonol-based Fluorescent Probe for Rapid Detection of H2S in Water, Foodstuff Samples and Living Cells

Abstract

A novel flavonol-based fluorescent probe, Fla-DNT, has been synthesized for the rapid and specific detection of H₂S. Fla-DNT exhibits excellent selectivity and anti-interference properties, a short response time (4 min), large Stokes shift (138 nm), and low detection limit (1.357 µM). Upon exposure to H₂S, Fla-DNT displays a remarkable increase in fluorescence intensity at 542 nm. Meanwhile, the recognizing site of H₂S was predicted through Electrostatic potential and ADCH charges calculations, while the sensing mechanism of H₂S was determined via HRMS analysis and DFT calculation. More importantly, the probe owes multiple applications, such as a recovery rate ranging from 92.00 to 102.10% for detecting H₂S in water samples, and it can be fabricated into fluorescent strips to track H₂S production during food spoilage by tracking color changes, thereby enabling real-time monitoring of food freshness. The bioimaging experiments demonstrate the capability of Fla-DNT to detect both endogenous and exogenous H₂S in living cells. These results provide a reliable method and idea for H₂S detection in complex environments.

Keywords: Bioimaging; Foodstuff; Hydrogen sulfide; Ultrasensitive; Water samples.