Development of dansyl based copper(II) complex to detect hydrogen sulfide in hypoxia

Hydrogen sulfide (H₂S) has been reported as a gaseous signaling molecule in cells. H₂S modulation is dependent on the partial pressure of oxygen in cells, which means hypoxia can induce H₂S production under various pathophysiological conditions. Hypoxia is a common condition in solid tumors and can lead to malignant tumors that may become aggressive and result in worse prognosis. We designed and synthesized probe Cu-CD for H₂S detection under hypoxia conditions. It is selective and sensitive toward various biological thiols, reactive nitrogen species (RNS), and reactive oxygen species (ROS). The fluorescence intensity of Cu-CD in the cytoplasms of HeLa and EMT6 cells was enhanced in proportion to the concentration of exogenous/endogenous H₂S. Moreover, Cu-CD can be able to detect endogenous H₂S production accompanied by expression of HIF-1α. Therefore, Cu-CD can be a key tool to explore how H₂S contributes to neovascularization and growth of solid tumor tissues in pathophysiological or hypoxic conditions.