Near-infrared fluorescent probe for visualizing hydrogen sulfide fluctuations during arthritis and its treatment

•A novel near-infrared H2S fluorescent probe, NIR-Ar-H2S, has been rationally constructed.•The probe NIR-Ar-H2S exhibited excellent selectivity, good optical stability, large Stokes shifts and low detection limits (0.18 μM).•The probe NIR-Ar-H2S enables the detection of exogenous and endogenous H2S in cells, zebrafish and mice.•The probe NIR-Ar-H2S enables the detection of H2S fluctuations in arthritis and its treatment.