LAUSR

Abstract A new quinoline-based chemosensor, 1,3-dioxoisoindolin-2-yl quinoline-2-carboxylate (DQC) was synthesized and characterized by ESI-MS, 1H NMR, 13C NMR and FT-IR. The binding ability of DQC towards different metal ions was investigated by UV–visible and fluorescence studies. The chemosensor displayed high selectivity and sensitive “on-off” fluorescence response towards Fe3+ in DMSO/H2O solution (8:2, v/v). The binding constant value of DQC with Fe3+ was calculated to be 0.71 × 102 M−1 and 0.77 × 102 M−1 using Benesi-Hildebrand plot by UV–vis and fluorescence spectroscopic methods. The sensor shows excellent linearity with a detection limit of 9.9 × 10−8 M and 16 × 10−8 M from UV–vis and fluorescence titration studies respectively. Job's plot analysis exhibits the 1:1 mode of binding between DQC and Fe3+. Moreover, the binding mechanism of Fe3+ with DQC was confirmed by DFT study.