Coumarin Based Fluorescent Probe for Colorimetric Detection of Fe3+ and Fluorescence Turn On-Off Response of Zn2+ and Cu2

• Published in: Journal of fluorescence 2017-07, Vol.27 (4), p.1307-1321
• Main Authors: Roy, Nayan, Dutta, Abhijit, Mondal, Paritosh, Paul, Pradip C., Sanjoy Singh, T.
• Format: Article
• Language: English
• Subjects: Absorption; Alkali metals; Analytical Chemistry; Biochemistry; Biological and Medical Physics; Biomedical and Life Sciences; Biomedicine; Biophysics; Biotechnology; Color; Colorimetry; Coordination compounds; Copper; Coumarin; Density functional theory; Detection; Emission spectroscopy; Energy gap; Ethylenediaminetetraacetic acids; Fluorescence; Gates; Ligands; Logic circuits; Metal ions; Methylene; Original Article; Spectra; Spectral density function; Titration
• ISSN: 1053-0509; 1573-4994
• DOI: 10.1007/s10895-017-2065-7

A new coumarin based Schiff-base chemosensor-(E)-7-(((8-hydroxyquinolin-2-yl)methylene) amino)-4-methyl-2H-chromen-2-one ( H 11 L ) was synthesized and evaluated as a colorimetric sensor for Fe 3+ and fluorescence “turn on-off” response of Zn 2+ and Cu 2+ using absorption and fluorescence spectroscopy. Upon treatment with Fe 3+ and Zn 2+ , the absorption intensity as well as the fluorescence emission intensity increases drastically compared to other common alkali, alkaline earth and transition metal ions, with a distinct color change which provide naked eye detection. Formation of 1:1 metal to ligand complex has been evaluated using Benesi-Hildebrand relation, Job’s plot analyses, 1 H NMR titration as well as ESI-Mass spectral analysis. The complex solution of H 11 L with Zn 2+ ion exhibited reversibility with EDTA and regenerate free ligand for further Zn 2+ sensing. H 11 L exhibits two INHIBIT logic gates with two different chemical inputs (i) Zn 2+ (IN1) and Cu 2+ (IN2) and (ii) Zn 2+ (IN1) and EDTA (IN2) and the emission as output. Again, an IMPLICATION logic gate is obtained with Cu 2+ and EDTA as chemical inputs and emission as output mode. Both free ligand as well as metal-complexes was optimized using density functional theory to interpret spectral properties. The corresponding energy difference between HOMO-LUMO energy gap for H 11 L , H 11 L-Zn 2+ and H 11 L-Cu 2+ are 2.193, 1.834 and 0.172 eV, respectively.