A 3-hydroxythalidomide-based fluorescent probe for detection of fluoride in water sample and bioimaging in living cells

Thalidomide and its derivatives were drawing attentions as an old drug since the cereblon (CRBN) as a thalidomide-binding protein was identified. Herein, we reported its novel application in ion detection for the first time. And a turn-on fluorescent fluoride probe, (4-((tert-butyldimethylsilyl)oxy)-2-(2,6-dioxopiperidin-3-yl) isoindoline-1,3-dione was prepared using a protection-deprotection design strategy taking 3-hyroxythalidomide as parent compound. High selectivity and sensitivity for fluoride ion were observed with significant green fluorescent responses and a remarkable Stokes shift (about 178 nm). The fluorescent change was based on the exited state intramolecular proton transfer mechanism, which had been established by in-situ Fourier transform infrared spectroscopy and H-1 NMR techniques. In addition, the probe was successfully applied to detect the fluoride ion in lake water. More importantly, the probe was almost nontoxic to the cultured cells and was applied in bioimaging in living cells.