Selective recognition of acetate ion based on fluorescence enhancement chemosensor

Fluorescence study of the complexation between uranyl salophen (L) and some common anions in acetonitrile-water (90:10, v/v) solution showed a tendency of L toward acetate ion (AcO-). The fluorescence enhancement of L is attributed to a 1:1 complex formation between L and acetate ion which was utilized as the basis for the selective detection of AcO-. The association constant of the 1:1 complex formation of L-AcO- was calculated as 6.60 × 10(6) . The linear response range of the fluorescent chemosensor covers a AcO- concentration range of 1.6 × 10(-7) to 2.5 × 10(-5)  mol/L, with a detection limit of 2.5 × 10(-8)  mol/L. L showed a selective and sensitive fluorescence enhancement response toward acetate ion over I3- , NO3-, CN-, CO3 (2-), Br-, Cl-, F-, H2 PO4- and SO4 (2-) , which was attributed to the higher stability of inorganic complex between acetate and L.