Molecular engineering of a colorimetric two-photon fluorescent probe for visualizing H2S level in lysosome and tumor.

As a multifunctional signaling molecule, hydrogen sulfide (H2S) plays an essential role in diverse physiological and pathological processes. The two-photon fluorescence probes detecting H2S selectively in vivo could be useful tools to better study the mechanism of diseases. Then, an efficient two-photon lysosome-specific probe 1 has been developed to detect endogenous H2S in living cells and mice. Probe 1 displays excellent properties with 28-fold fluorescence enhancement, marked color changes in naked-eye and fluorescence, high selectivity and sensitivity, and low detection limit (0.22 μM) to H2S. These remarkable properties of probe 1 enable its practical applications in detecting H2S in environment (wastewater) and food (beer). Moreover, as a two-photon probe under near infrared excitation at 790 nm, probe 1 can monitor the level changes of endogenous H2S of lysosome and tumor in living system with good membrane permeability and high imaging resolution. Specially, the probe detecting H2S distribution in lysosome could provide more evidences to explain the association of target-organelle and H2S.