Bioimaging of a fluorescence rhodamine-based probe for reversible detection of Hg (II) and its application in real water environment

Abstract Mercury is a typical serious pollutant certified by relevant authorities, it is harmful not only to biological health but also to the ecological environment and its superior detection approach remains challenging. About this research, a novel reversible fluorescent probe(RBST) based on 2-Thiopheneacetyl chloride and Rhodamine B was designed，synthesized and established to develop as a chemosensor. Its sensing behavior, especially for various common metal ions, was detected by UV–vis spectrum and fluorescence spectrum. RBST displayed a satisfactory sensitivity and selectivity fluorescent response towards Hg2+ in a solution of EtOH/H2O (2,1, v/v), giving a higher combining constant of 3.03 × 104 M−1 and a lower detection limit of 0.11 μM respectively. Fluorescence quenched presented a reversible behavior with a certain amount of S2− was added under the condition of containing Hg2+. Besides, the practicality of the probe in sensing Hg2+ in real water samples was further proved. Results of this study suggested that the fluorescent reversible probe excels in biological applications and can be applied in MCF-7 cells, zebrafish and soybean rhizome tissues to detect Hg2+.