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A dual-mode highly selective and sensitive Schiff base chemosensor for fluorescent colorimetric detection of Ni2+ and
Amit Kumar Manna1, Kalyani Rout, Shubhamoy Chowdhury
1Department of Chemistry, Guru Ghasidas Vishwavidyalaya, Bilaspur, C.G, India. patra29in@yahoo.co.in.
Abstract:
In this paper, a novel flexible Schiff base chemosensor N'-(2-hydroxy-3-methoxybenzylidene)-2-(benzamido)benzohydrazide (L) has been designed, synthesised and characterised by 1H-NMR, IR spectroscopy, ESI-MS spectrometry and single crystal XRD analysis. A significant fluorescence enhancement of L was observed only in the presence of Ni2+ ions with a detection limit of 3.64 μM whereas Cu2+ induced fluorescence quenching, although both the metals showed colorimetric responses in methanol-Tris-HCl buffer (10 mM, pH 7.2) solution (1 : 1, v/v). The single crystal structure of L-Cu2+ has also been determined. No major interference by the other effective background cations (Fe3+, Fe2+, Co2+, Zn2+, Cd2+, Hg2+, Pb2+, Cr3+, Ag+, Al3+ and Mn2+) was observed even at a higher concentration of analytes. The experimental results were further supported by DFT studies. The chemosensor L can be applied to the formation of binary logical devices, recovery of contaminated water samples and living intracellular media.
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