Bis-Schiff base as a donor–acceptor fluorescent probe: Recognition of Al3+ ions in near 100% aqueous solution

• A novel bis-Schiff base fluorescent probe for Al3+ has been designed and synthesized.
• The probe for Al3+ shows significant fluorescence enhancement accompany with about 40 nm blue shift on the basis of the mechanism of ICT.
• The detection limit for Al3+ reached at 10−7 M level in 100% aqueous solution.

In this paper, a novel bis-Schiff base fluorescent probe (HL) for Al3+ has been designed and synthesized on the basis of the mechanism of internal charge transfer (ICT). Compared with the free receptor, the fluorescence intensity of HL shows significant fluorescence enhancement accompany with about 40 nm blue shift in the presence of Al3+. More importantly, the lowest detection limit for Al3+ can reach at 10−7 M level in near 100% aqueous solution.

Upon addition of Al3+, compared with the free receptor, the fluorescence intensity of HL shows significant fluorescence enhancement accompany with about 40 nm blue shift in the presence of Al3+, the reasons for this phenomenon are attributed to forms 1:1 complex which inhibit internal charge transfer process.Figure optionsDownload as PowerPoint slide