Faculty Publications

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    Colorimetric anion sensors based on positional effect of nitro group for recognition of biologically relevant anions in organic and aqueous medium, insight real-life application and DFT studies
    (Elsevier B.V., 2018) Singh, A.; Sahoo, S.K.; Trivedi, D.R.
    A new six colorimetric receptors A1-A6 were designed and synthesized, characterized by typical common spectroscopic techniques like FT-IR, UV–Visible, 1H NMR, 13C NMR and ESI-MS. The receptor A1 and A2 exhibit a significant naked-eye response towards F? and AcO? ions in DMSO. Due to presences of the NO2 group at para and ortho position with extended ?-conjugation of naphthyl group carrying –OH as a binding site. Compared to receptor A2, A1 is extremely capable of detecting F? and AcO? ions present in the form of sodium salts in an aqueous medium. This is owed to the occurrence of –NO2 group at para position induced in increasing the acidity of –OH proton. Consequently, it easily gets deprotonated in aqueous media. The detection limit of receptor A1 was turned out to be 0.40 and 0.35 ppm for F? and AcO? ions which is beneath WHO permission level (1.0 ppm). Receptor A1 shows a solitary property of solvatochromism in different aprotic solvents in presence of AcO? ion. Receptor A1 depicts high selectivity towards AcO? ion in DMSO: HEPES buffer (9:1, v/v). Receptor A1 proved itself for real life application by detecting anion in solution and solid state. The binding mechanism of receptor A1 with AcO? and F? ions was monitored from 1HNMR titration and DFT study. © 2017 Elsevier B.V.
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    Hg 2+ induced hydrolysis of thiazole amine based Schiff base: Colorimetric and fluorogenic chemodosimeter for Hg 2+ ions in an aqueous medium
    (Elsevier B.V., 2019) Tekuri, V.; Sahoo, S.K.; Trivedi, D.
    Simple pyrene-based chemosensors 1 to 3, were synthesized from pyrene-1-carboxaldehyde and they were characterized using various spectroscopic techniques like UV–Vis, FT-IR, Mass, 1 H NMR and 13 C NMR. Among synthesized receptors, the receptor 1 shows high selectivity towards Hg 2+ ions. Further, the high selectivity of receptor 1 towards Hg 2+ ions in the presence of various other interfering metal ions like Ni 2+ , Zn 2+ , Mn 2+ , Co 2+ , Cu 2+ , Cr 3+ , Fe 3+ , Al 3+ , Ag + , Fe 2+ , Cd 2+ , Mg 2+ , Pb 2+ , Ca 2+ , Na + , K + was confirmed by UV–Vis and fluorescence methods. The detection limit for Hg 2+ ions was found to be 0.270 ?M. The chemodosimetric irreversible hydrolysis of the receptor 1 in the presence of Hg 2+ was studied by UV/Vis, fluorescence, FT-IR, LC-MS, 1 H NMR and theoretical DFT study. Further, the real life applications of receptor 1 for the determination of Hg 2+ ions were demonstrated by UV–Vis method. © 2019 Elsevier B.V.