Thiophene-based rhodamine as selectivef luorescence probe for Fe(III) and Al(III) in living cells

The thiophene-modified rhodamine 6G (GYJ) has been synthesized as a novel chemosensor. The sensor has sufficiently high selectivity and sensitivity for the detection of Fe³⁺ and Al³⁺ ions (M³⁺) by fluorescence and ultraviolet spectroscopy with a strong ability for anti-interference performance. The binding ratio of M³⁺-GYJ complex was determined to be 2:1 according to the Job's plot. The binding constants for Fe³⁺ and Al³⁺ were calculated to be 3.91 × 10⁸ and 5.26 × 10⁸ M^-2, respectively. All these unique features made it particularly favorable for cellular imaging applications. The obvious fluorescence microscopy experiments demonstrated that the probes could contribute to the detection of Fe³⁺ and Al³⁺ in related cells and biological organs with satisfying resolution. Graphical abstract GYJ has high selectivity and sensitivity for the detection of Fe(III) and Al(III) with the binding ratio of 2:1.