A novel turn-on fluorescence probe L has been designed that exhibits high selectivity and sensitivity with a detection limit of 9.53 × 10−8 mol/L for the quantification of Zn2+. 1H-NMR spectroscopy and single crystal X-ray diffraction analysis revealed the unsymmetrical nature of the structure of the Schiff base probe L. An emission titration experiment in the presence of different molar fractions of Zn2+ was used to perform a Job’s plot analysis. The results showed that the stoichiometric ratio of the complex formed by L and Zn2+ was 1:1. Moreover, the molecular structure of the mononuclear Cu complex reveals one ligand L coordinates with one Cu atom in the asymmetric unit. On adding CuCl2 to the ZnCl2/L system, a Cu-Zn complex was formed and a strong quenching behavior was observed, which inferred that the Cu2+ displaced Zn2+ to coordinate with the imine nitrogen atoms and hydroxyl oxygen atoms of probe L.
<p>We report
efficient synthesis and photophysical properties of a novel fluorescent
pyridothiazole based construct by a facile methodology and its application as a
sensor for rapid, selective as well as sensitive detection of amyloid fibres.
The novel compound has exceptionally high quantum yield and sensitivity. The
fluorescence of pyridothiazole construct is completely quenched (Turn-OFF) upon
addition of cupric ions and the fluorescence is recovered on addition of
amyloidogenic peptides like A<i>β</i><sub>42
</sub>(Turn-ON). The control experiment with native and heat treated BSA
suggest that the new probe binds to beeta/<i>β</i> sheets
present in amyloid. The new probe offers direct visualization of
fluorescence ‘Turn-OFF’ ‘Turn-ON’ under long UV without the use of
sophisticated instrumentation. Hence,
a very simple, facile and cost-effective methodology for the rapid detection of
amyloid is presented and it may in all possibility pave the way for the design
of a better probe for sensing amyloids than conventional ThT.</p>
We developed a small organic molecule, the 1,3,6,8-Tetrakis(pbenzoic acid)pyrene (TBAPy) as a facile turn-on fluorescence probe for selectively detecting the basic protein protamine in water with a low detection limit...
A novel, highly sensitive and fast responsive turn-on fluorescence probe ADMPA for Cd2+ was successfully developed based on 2,9-dimethyl-1,10-phenanthroline and o-aminophenol.