Two-Input Fluorescent Probe for Thiols and Hydrogen Sulfide Chemosensing and Live Cell Imaging

Development of multi-input fluorescent probes would facilitate the monitoring of multiple biomolecular events leading to a common disease pathology. Here, we reported a two-input fluorescent probe (QME-N 3 ) based on quinoline scaffold with two distinct reactive sites, the α,β-unsaturated carbonyl at 2-site and 6-azido group, which were specific acceptors of RSH and H 2 S respectively. The turn-on fluorescent probe could react with the two molecules via the Michael addition at the double bond for RSH and the reduction of the azide by H 2 S without mutual interference, to generate the intensively fluorescent product, which could act as a two-input AND logic gate. Furthermore, QME-N 3 has very low cytotoxicity and excellent stability, and the resulting sensing product has a high two-photon absorption cross section. Consequently, detection of intracellular thiols and H 2 S can be achieved by cell fluorescence imaging under both one- and two-photon excitations.