An Activatable Near-Infrared Fluorescence Hydrogen Sulfide (HS) Donor for Imaging HS Release and Inhibiting Inflammation in Cells.

Hydrogen sulfide (HS) is a vital endogenous signal molecule that exerts critical physiological functions such as biological regulation and cytoprotection. Despite significant progress in developing HS donors, site-specific delivery and controllable release of HS in biological systems remain a key challenge. Herein, we develop new Cys-triggered fluorescent HS donor that is composed of a dicyanoisophorone-based near-infrared (NIR) fluorescent dye and a thiocarbamate moiety. The HS donor releases HS under the attack of Cys, accompanied by the release of a fluorescent reporter, which enables the real-time capturing of HS by fluorescence spectroscopy or microscopy. exhibits strong NIR fluorescence enhancement (70-fold), excellent controllable HS release (30 min), high HS release efficiency (62%), and well live-cell compatibility, allowing for visualization of HS release in cells and zebrafish. Moreover, presents a good effect of anti-inflammation in RAW 264.7 cells. This work provides a new idea for the design of HS donors, which may be beneficial to the comprehension of the potential mechanism of inflammation and optimization of treatment strategies.