A new coumarin based dual functional chemosensor for colorimetric detection of Fe3+ and fluorescence turn-on response of Zn2+

• DOI: 10.1016/j.snb.2016.06.061
• Publication Date: 2016-06-14T12:09:32Z
• Authors: Nayan Roy; Abhijit Dutta; Paritosh Mondal; Pradip C. Paul; T. Sanjoy Singh
• Keywords: Stoichiometry; Methylene

Abstract A new coumarin based Schiff-base dual chemosensor-( E )-2-(((8-hydroxyquinolin-2-yl)methylene)amino)-6H-benzo[c]chromen-one (H 10 L) was synthesized and characterized. This chemosensor was evaluated as a colorimetric sensor for Fe 3+ and fluorescence turn-on response for Zn 2+ among the various survey metal ions. The stoichiometric ratio and association constant were evaluated using Benesi-Hildebrand relation giving 1:1 stoichiometry. This further corroborated 1:1 complex formation based on Job’s plot analyses. The complex solution of H 10 L with Zn 2+ ion exhibited reversibility with EDTA and regenerate free ligand for further Zn 2+ sensing. H 10 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 an 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 optimised using density functional theory. The calculated vibrational frequency confirms that both are at local minima on the potential energy surfaces. The corresponding energy difference between HOMO and LUMO of H 10 L, Zn-complex and Cu-complex are found to be 3.67, 1.63 and 2.01 eV, respectively. The Cu-complex is found to be more stable than Zn-complex as Cu-complex has higher hardness value compare to Zn-complex.