KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Search Results

Now showing 1 - 2 of 2
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Bodipy-pyridylhydrazone probe for fluorescence turn-on detection of fe3+ and its bioimaging application
    (2021-07-01)
    Nootem, Jukkrit
    ;
    Sattayanon, Chanchai
    ;
    Daengngern, Rathawat
    ;
    Kamkaew, Anyanee
    ;
    Wattanathana, Worawat
    A novel pyridylhydrazone-tethered BODIPY (BODIPY-PH) was synthesized, fully characterized via nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopic (FTIR), and single-crystal X-ray diffraction (SC-XRD) techniques, and developed for the selective detection of Fe<sup>3+</sup> through fluorescent enhancement process. This derivative showed 1:1 binding with Fe<sup>3+</sup> in an acetonitrile-water mixture (1:9 v/v) with the binding constant (K) of 5.4 × 10<sup>4</sup> M<sup>−1</sup> and the limit of detection of 0.58 µM. The Fe<sup>3+</sup> complexation reaction has been proved to be a reversible process and could be effectively repeated up to three cycles. The electronic properties of BODIPY-PH and its Fe<sup>3+</sup> complex modeled by the density functional theory (DFT) method suggested the presence of chelation-enhanced fluorescence (CHEF) effect in the Fe<sup>3+</sup> binding reaction. The X-ray absorption spectroscopy (XAS) probed at Fe K-edge confirmed the complex formation between BODIPY-PH and the Fe<sup>3+</sup> in an octahedral geometry. Finally, bioimaging against human embryonic kidney (Hek293) cell, through confocal fluorescence microscopic technique indicated that the BODIPY-PH displayed good permeability and low toxicity toward the tested cell lines and showed enhanced fluorescent signal in the cells incubated with Fe<sup>3+</sup> proving its capability for Fe<sup>3+</sup> analysis in cellular matrix.
  • Some of the metrics are blocked by your 
    Item type:Publication,
    The synergy of CHEF and ICT toward fluorescence ‘turn-on’ probes based on push-pull benzothiazoles for selective detection of Cu2+ in acetonitrile/water mixture
    (2021-06-15)
    Nootem, Jukkrit
    ;
    Daengngern, Rathawat
    ;
    Sattayanon, Chanchai
    ;
    Wattanathana, Worawat
    ;
    Wannapaiboon, Suttipong
    New push-pull schiff base ligands based on benzothiazole (BZ) unit were developed for the selective detection of Cu<sup>2+</sup> through fluorescence ‘turn-on’ mechanism. These derivatives with electron withdrawing trifluoromethyl (-CF<inf>3</inf>) and cyano (-CN) substituents (BZ2 and BZ3) demonstrated a prominent fluorescence enhancement upon copper ion binding which could be the results from the synergistic effect between the chelation-enhanced fluorescence (CHEF) and the intramolecular charge transfer (ICT) processes. In addition, these compounds displayed 1:1 binding with Cu<sup>2+</sup> with low limits of detection of 0.77 μM and 0.64 μM for BZ2 and BZ3, respectively, in acetonitrile-water (3:1 v/v) media. The electronic and photophysical properties of these BZ ligands and the copper ion complexes were modelled by the density functional theory (DFT) and the time-dependent density functional theory (TD-DFT) calculations, respectively. Analysis of X-ray absorption spectra probed at Cu K-edge of Cu<sup>2+</sup>-BZ mixtures revealed the complex formation of BZ ligands with the targeted Cu<sup>2+</sup> and confirmed the non-centrosymetric structures of the complexes as predicted by the DFT calculation. The electron density distributions of the HOMO-LUMOs in the computational results as well as large stokes shifts of the ligand-metal complexes in the experimental data confirmed the strong ICT effect after Cu<sup>2+</sup> binding which is a key process promoting fluorescence ‘turn-on’ mechanism.