A novel rhodamine-based fluorescent and colorimetric 'off—on' chemosensor and investigation of the recognizing behavior towards Fe~(3+)

摘要

A novel rhodamine based probe has been synthesized as an "off—on" chemosensor for Fe~(3+). Upon coordination with Fe~(3+), the probe displayed good brightness and fluorescent enhancement. A linear relationship was observed to exist between the relative fluorescence intensity of this probe and the concentration of Fe~(3+) in the range of 5 μM—20 μM with a detection limit of 5 μM. It offered highly sensitive toward Fe~(3+) over other ions. The recognizing behaviors toward Fe~(3+) have been investigated both experimentally and computationally. It can be expected that Fe~(3+) coordinated with the N atom of thiazole moiety in the probe accompanied by the transferring of electrons of the phenylthiazole resulted in the opening of the spiro-ring.