Real-Time Imaging of Hepatic Inflammation Using Hydrogen Sulfide-Activatable Second Near-Infrared Luminescent Nanoprobes.

The sensing and visualized monitoring of hydrogen sulfide (H2S) in vivo is crucial to understand its physiological and pathological roles in human health and diseases. Common methods for H2S detection require the destruction of the biosamples and are not suitable to be applied in vivo. In this Communication, we report a "turn-on" second near-infrared (NIR-II) luminescent approach for sensitive, real-time, and in situ H2S detection, which is based on the absorption competition between the H2S-responsive chromophores (compound 1) and the NIR-II luminescent lanthanide nanoparticles. Specifically, the luminescence was suppressed by compound 1 due to the competitive absorption of the incident light. In the presence of H2S, the compound 1 was bleached to recover the luminescence. Thanks to the deep tissue penetration depth and the low absorbance/scattering on biological samples of the NIR-II nanoprobes, the monitoring of the endogenous H2S in lipopolysaccharide-induced liver inflammation was achieved, which is unattainable by the conventional histopathological and serological approaches.