An easily available lysosomal-targeted ratiometric fluorescent probe with aggregation induced emission characteristics for hydrogen polysulfide visualization in acute ulcerative colitis

Hydrogen polysulfide (H2Sn, n >1), as a direct oxidizing form of hydrogen sulfide, is closely associated with intestinal diseases such as ulcerative colitis (UC). A probe that can selectively detect H2Sn in the pathological environment of UC is in urgent demand. Ratiometric probes are powerful in the quantitative detection of H2Sn in living organisms. Herein, we developed a ratiometric fluorescent probe TCFPB–H2Sn for selective detection of H2Sn in vitro and in vivo. Significantly, TCFPB–H2Sn demonstrated a fast, sensitive and specific detection performance for H2Sn, and has excellent lysosomal targeting ability and aggregation-induced emission (AIE) characteristics. More importantly, TCFPB–H2Sn was the first probe to achieve endogenous H2Sn imaging in acute ulcerative colitis successfully.