A naphthalene derivative as 'turn-on' fluorescent chemosensor for the highly selective and sensitive detection of Al³

A Schiff base compound derived from naphthalene has been synthesized and characterized as an Al³⁺ -selective fluorescent probe. The chemosensor (L) exhibits high selectively for Al³⁺ in aqueous solution, even in the presence of biologically relevant cations such as Na⁺ , K⁺ , Ca²⁺ , Mg²⁺ , Pb²⁺ and several transition metal ions. There was no observed interference from anions like Br^- , Cl^- , HSO₃^- , SO₃^2- , S₂ O₃^2- , NO₂^- , CO₃^2- and AC^- . The lowest detection limit for the chemosensor L was found to be 1.89 × 10^-8  M with a linear response towards Al³⁺ over a concentration range of 5 × 10^-6 to 4 × 10^-5  M. Furthermore, the proposed chemosensor has been used for imaging of Al³⁺ in two different types of cells with satisfying results, which further demonstrates its value for practical application in biological systems.