"Turn-on" far-red fluorescence sensor for Y3+ based on Schiff-based tetraphenylethylene.

Far-red and "turn-on" fluorescence sensors were paid much attention due to their outstanding merits, but this kind of fluorescence probe for Y3+ was not presented up to date. In this work, a Schiff-base bridged m -aminobenzoic acid-decorating tetraphenylethylene was designed and synthesized in yield of 89%. It exhibited the far-red fluorescence at 550–670 nm in aqueous media based on AIE effect. It showed high selective sensing ability for Y3+ among all kinds of metal ions with the obvious "turn-on" fluorescence, which was observed for the first time for fluorescence sensor of Y3+. The detection limit for Y3+ was as low as 2.23 × 10−7 M. The sensor mechanism of 1:1 stoichiometric ratio was clarified by fluorescence titration, FT-IR spectra, 1H NMR and MS spectra. The selective sensing of Y3+ was further successfully applied on detecting Y3+ for tested paper, simulated water sample and bio-imaging of live cells, suggesting the good practical application potential of this fluorescence sensor on detecting Y3+ in complicated water media and living body environment. • First "turn-on" fluorescence sensor for Y3+ in water media was presented. • The high selective sensing ability for Y3+ among various metal ions was observed. • The detection limit for Y3+ was as low as 2.23 × 10−7 M. • The Y3+ sensor was applied for tested paper, simulated water sample and bio-imaging. • The sensor mechanism of 1:1 stoichiometric ratio was clarified. [ABSTRACT FROM AUTHOR]