Schiff Base Derived from 4,4′-methylenedianiline and p-anisaldehyde: Colorimetric Sensor for Cu2+, Paper Strip Sensor for Al3+ and Fluorescent Sensor for Pb2

• Published in: Journal of fluorescence 2019-11, Vol.29 (6), p.1467-1474
• Main Authors: Das, Diganta Kumar, Deka, Satyapriya, Guha, Ankur Kanti
• Format: Article
• Language: English
• Subjects: Aluminum; Analytical Chemistry; Binding; Biochemistry; Biological and Medical Physics; Biomedical and Life Sciences; Biomedicine; Biophysics; Biotechnology; Cobalt; Colorimetry; Condensates; Copper; Ethanol; Fluorescence; Imines; Lead; Manganese; Mathematical analysis; Mercury (metal); Metal ions; Methylene dianiline; Original Article; Sensors; Stoichiometry; Strip
• ISSN: 1053-0509; 1573-4994
• DOI: 10.1007/s10895-019-02443-8

The condensation product ( L ) of 4,4′-methylenedianiline and p-anisaldehyde acts as colorimetric sensor for Cu 2+ and Pb 2+ ions. On interaction with Cu 2+ , ethanolic solution of L changes its color to brown while it becomes light pink on interaction with Pb 2+ . Interaction of Al 3+ with L coated paper strip emits bright blue fluorescence. Metal ions like Mg 2+ , Cu 2+ , Li + , K + , Na + , Mn 2+ , Al 3+ , Hg 2+ , Co 2+ , Pb 2+ , Ni 2+ , Cd 2+ , Zn 2+ , Fe 3+ do not interfere the paper strip sensor. The fluorescent intensity of L in ethanol is quenched 25 times by Pb 2+ ion. The interaction between L and Pb 2+ is reversible and the detection limit of Pb 2+ is 10 −6  M. The binding constant and stoichiometry of binding between L and Pb 2+ was calculated to be 10 4.8 and 1:2. Theoretical calculations show that the binding of the metal ions to L are favorable and the fluorescence of L is due to π → π* transition.