N-quaternization of heterocyclic compound extended the emission to NIR with large Stokes shift and its application in constructing fluorescent probe

N-quaternization of QOH could extend its emission from 555 nm to 720 nm and endow it mitochondrial targeting capabilities. The wavelength red-shift independent on the properties of substituent. QOH successfully be used to construct probe for detecting H2S (Q-SH) with “Turn-on” signal and H2O2 (QM-R) with ratio fluorescence in vitro and in vivo.