Highly Sensitive and Selective Fluorescent Probe for Detection of Fe Based on Rhodamine Fluorophore.

A simple rhodamine-based fluorescent probe L1, which exhibits good response to Fe in CHCN/Tris-HCl buffer (v:v = 9:1, pH 7.00) solution. With the experimental conditions optimized, the probe L1 could be used as a fluorescent and colorimetric probe for Fe with the detection limit as low as 0.29 μM. The binding constant (K) of Fe binding to the probe L1 were calculated to be 1.4 × 10 M, respectively from a Benesi-Hildebrand plot. With the addition of Fe, the CHCN/Tris-HCl buffer (v:v = 9:1, pH 7.00) solution of the probe L1 exhibited a obviously color change from transparent to pink with distinctive changes. More importantly, the recognition process of the probe L1 for Fe was chemically reversible on the addition AcO. Graphical Abstract.