A novel BODIPY-derived colorimetric and ratiometric dual-mode fluorescent probe for highly sensitive and visual detection of sulfite in food and living organisms.

Sulfite, widely used as a food additive, performs indispensable functions in the field of food sterilization, bleaching, and antisepsis. However, the overuse of sulfite may destroy food nutrition and pose health risks to people. In this work, an innovative BODIPY-based fluorescent probe (BODIPY-DBC) was constructed for highly sensitive recognition of sulfite. The BODIPY-DBC probe possessed both colorimetric and ratiometric dual mode, a low detection limit (33.12 nM), high sensitivity, a wide pH usage range (5-12), a fast response time (2 min), and superior fluorescence imaging capability for detecting sulfite. The recognition mechanism was certificated by 1H NMR titration, HRMS analysis, and DFT calculation. The BODIPY-DBC probe was not only loaded on test strips for detecting sulfite conveniently with the naked eye, but also employed to detect sulfite content in real food samples to ensure food safety. Furthermore, it also achieved excellent performances for monitoring sulfite in dual-channel fluorescence imaging (HeLa cell and zebrafish).