A visible light excitable chromone appended hydrazide chemosensor for sequential sensing of Al+3 and F- in aqueous medium and in Vero cells

A probe, quinoline-2-carboxylic acid (4-oxo-4H-chromen-3-ylmethylene)-hydrazide, (HL), acts as selective and specific fluorogenic sensor to Al+3 in the visible light (435 nm) excitation in presence of biologically available large number of cations and emission appears at (lambda(em)) 520 nm. The limit of detection (LOD) for Al+3 is 7.6 nM in aqueous medium which is less than 10-3 times of WHO recommended data (7.41 mM). The Job's plot and mass spectral data support 1:1 composition of the complex [Al(HL)(OH)H2O](NO3)(2). The strongly emissive complex turns off upon addition of F-and is detected at the level of (LOD) 7.4 nM. Thus, F-, a harmful water pollutant, could be identified at much lower level of WHO recommended toxic limit (3.68 mu M). The absorption and emission spectral features of HL and its Al+3 -complex have been explained by DFT computation of optimized geometries and calculation of molecular functions. The devised receptor is non-toxic and has been used in detecting Al+3 in the intracellular region of African green monkey kidney cells (Vero cells) and exhibits an INHIBIT logic gate with Al+3 and F- as chemical inputs by monitoring the emission mode at 520 nm. (C) 2017 Elsevier B.V. All rights reserved.