1,6-Elimination reaction induced detection of fluoride ions in vitro and in vivo based on a NIR fluorescent probe

Near-Infrared “turn on” type fluorescent probes are attractive and promising in the fields of chemical sensing and bioimaging. Here, a new dicyanomethylene-4H-pyran derivative (DCM-Si) NIR fluorescent probe was designed and synthesized for specific lighting up F − in living cells and bodies. Si O bond was used as F − trigger, and the release of fluorophore (DCM-NH 2 ) occurred after substituent reaction and subsequent 1,6-elimination. This NIR probe displayed high sensitivity and selectivity for the sensing of F − , and the detection limit was calculated to be as low as 157 nM. Moreover, the “off-on” fluorescent signal changes can be realized by adding F − in living cells and zebrafish embryos.