A lysosome-targetable multifunctional fluorescent probe based on intramolecular NH…NH2 hydrogen bonding for detection of hypochlorite and cyanides

The creation of a singular fluorescent probe for the detection of various analytes is crucial for comprehending the interactions among analytes in living cells. This study presents a novel multifunctional fluorescent probe, designated Lyso-Nap-Py, which utilizes distinctive intramolecular NH^…NH₂ hydrogen bonding for the simultaneous detection of hypochlorite and cyanides within living cells. This probe demonstrates the ability to detect cyanides and hypochlorite, offering advantages including high selectivity, fluorescence turn-off at 638 nm, a low limit of detection, and rapid response times. The Lyso-Nap-Py-immobilized test papers demonstrated notable reversible colorimetric changes observable to the naked eye in response to fluctuations in environmental acidity and basicity, showcasing over four cycles of reversibility. The interactions of Lyso-Nap-Py with cyanides and HClO lead to alterations in emissions within the red channels, yielding specific signal responses to various analytes present in cellular lysosomes. Significantly, through the utilization of this singular probe, we accomplished the imaging of exogenous cyanides and hypochlorite, in addition to endogenous hypochlorite, within living cells and zebrafish. Furthermore, the advantageous features of probes that utilize intramolecular NH^…NH₂ hydrogen bonding demonstrate considerable promise for their use in cellular imaging within lysosomes.