A ratiometric fluorescent probe for sensitive and selective detection of hydrogen sulfide and its application for bioimaging

• A ratiometric fluorescence probe based on 1,8-naphthalimide for H2S is designed and synthesized.
• The probe can detect H2S in ratiometric manner with high selectivity and sensitivity.
• The probe mechanism is based on H2S-mediated nucleophilic addition followed by an intramolecular cyclization.
• The probe is applied to bioimagine of H2S.

A new 4-hydroxy-1,8-naphthalimide-based ratiometric fluorescent probe for hydrogen sulfide (H2S) detection was designed and synthesized. The probes showed fast response, high sensitivity and selectivity for hydrogen sulfide over other reactive sulfur species. The mechanism is based on H2S-mediated nucleophilic addition followed by an intramolecular cyclization to give the product, 4-hydroxy-1,8-naphthalimide, which showed outstanding intramolecular charge transfer (ICT). Therefore, ratiometric signal was observed and with a H2S detection of 1–10 μM. Furthermore, the probe successfully applied to bioimaging, demonstrating its potential applications in biological systems.