A novel naphthalimide-based probe for highly sensitive and selective recognition of fluoride ion.

Considering the excessive ingestion of fluoride ion (F − ) may result in many diseases, herein, by introducing 2-hydroxy-1-naphthaldehyde azine framework to 1,8-naphthalimide derivatives, we have developed a unique colorimetric/fluorometric probe (NYL) for detection of fluoride. The response of NYL toward F − is an integration of ESIPT and PET processes with a large stokes’ shift (173 nm). The striking color change from yellow to light-purple and fluorescent quenching of probe NYL can be observed only in the presence of fluoride ions. Furthermore, 1 H NMR titration indicates the probe undergoes the deprotonation of hydroxyl through the Hydrogen-bond interaction between phenolic O H and F − ions. [ABSTRACT FROM AUTHOR]