Discriminating Chemosensor for Detection of Fe 3+ in Aqueous Media by Fluorescence Quenching Methodology

The Schiff base as chemosensor (B) namely 2‐((anthracen‐1‐ylimino) methyl) phenol was designed and synthesized. The spectral properties of chemosensor B were confirmed by using IR, 1 H NMR, 13 C NMR, and LC–MS techniques. The chemosensor B shows a significant fluorescence quenching with incremental addition of Fe 3+ . The present chemosensor B shows unaffected fluorescence response induced by Fe 3+ even in the presence of other competing ions in mixed solvent system. The binding mode and stoichiometry (2:1) between chemosensor B and Fe 3+ were analyzed by recording 1 H NMR and Job's plot respectively. The ground state complexation of chemosensor B and Fe 3+ was confirmed by absorption titration and fluorescence lifetime measurement in the absence and presence of various concentration of Fe 3+ ion to chemosensor B. The lower detection limit for Fe 3+ found to be 0.59 μM with correlation coefficient R 2  = 0.9815. The present chemosensor B successfully applied for quantitative determination of the Fe 3+ ion from ordinary water samples.