A novel ratiometric fluorescent probe for selective detection of Hg2+, Cr3+ and Al3+ and its bioimaging application in living cells

A novel rhodamine-benzothiazole fluorescent probe L was designed and synthesized which can be selective detection of three kinds of metal ions (Hg2(+), Cr3(+) and Al3(+)), through the mechanism of fluorescence resonance energy transfer (FRET). This probe L shows good sensitivity towards Hg2(+), Cr3(+) and Al3(+) even at the sub-micromolar levels, which exhibited ratiometric fluorescence change from colorless to pink in aqueous media in a wide pH range of 510. Interestingly, the Jobs plot investigation suggested that L bounding to Hg2(+) or Al3(+) with a simple 1:1 mode and a 2:1 mode to Cr3(+) display different binding modes. Furthermore, the potential utility for biological applications was performed by fluorescence microscopic imaging in live cells. The results indicated that fluorescence probe L was a hopeful candidate for applications in the cell-imaging and safety inspection. (C) 2017 Elsevier B.V. All rights reserved.