A simple and effective dansyl acid based "turn-on" fluorescent probe for detecting labile ferrous iron in physiological saline and live cells.

Labile ferrous iron (Fe) plays important biochemical functions in many physiologically essential processes. It is very important to find an effective method to detect Fe. Herein, a simple and effective Fe fluorescent probe (FeP1) has been constructed via a unique strategy of Fe-induced reducing reaction. As expected, FeP1 exhibited a 'turn-on' fluorescence response toward Fe over various small analytes, with high selectivity and excellent sensitivity (DL = 18 nM) for the detection of Fe in Tris-DMSO (4:1, pH = 7.4, v/v) solution. Moreover, the probe can act in different real samples, such as physiological saline and living cells.