Turn-on fluorescent chemosensor for Zn(ii) via ring opening of rhodamine spirolactam and their live cell imaging

A new rhodamine based selective and sensitive turn-on fluorescent Zn2+chemosensor has been developed. A prominent fluorescence enhancement was found in the presence of Zn2+, which was accompanied by changes in the absorption spectrum. The new sensor showed ‘naked-eye’ detection of Zn2+ ions: a color change of the solution from colorless to pink. Furthermore, by means of confocal laser scanning microscopy experiments, it has been demonstrated that it can be used as a fluorescent probe for monitoring Zn2+ in living cells.