Highly selective on-off fluorescence recognition of Fe3+ based on a coumarin derivative and its application in live-cell imaging.

A novel coumarin chemosensor, 7-hydroxy-2-oxo-N-(pyridin-2-ylmethyl)chromene-3-carboxamide (Probe 1) , demonstrated significant selectivity towards Fe 3+ ions. Probe 1 exhibited high fluorescence emission profile at 447 nm, excellent selectivity towards Fe 3+ over other biologically important metal ions (Al 3+ , Ba 2+ , Co 2+ , Cu 2+ , Zn 2+ , Cd 2+ , Hg 2+ , Pb 2+ and Sn 2+ ). Interestingly, there was ~ 30-fold decrease in fluorescence intensity upon Fe 3+ binding. The limit of detection of Fe 3+ was found to be 0.76 μM (~ 40 ppb). Probe 1 also exhibited high potential as an intracellular chemosensor for Fe 3+ . [ABSTRACT FROM AUTHOR]