A simple chromone-derived fluorescent "Turn-on" probe for accurate detection of Al Ions: Applications in food Analysis, test strips and bioimaging.

To address the toxicity concerns of aluminum ions (Al) due to their widespread environmental presence, a novel chromone-derived fluorescent probe, (E)-N'-((4-oxo-4H-chromen-3-yl)methylene)benzohydrazide (NMA), was developed for dual-mode detection combining colorimetric and fluorometric channels. Upon chelation with Al in a 1:1 stoichiometric ratio, NMA exhibited a significant fluorescence enhancement at 510 nm, accompanied by a rapid and visible color change due to the chelation-enhanced fluorescence (CHEF) effect, achieving an exceptional detection limit of 9 nM-well below the World Health Organization's recommended threshold. The reversible binding of NMA, demonstrated through sequential addition of Al and EDTA, enabled the construction of an INHIBIT molecular logic gate, broadening its potential for smart sensing applications. Structural interactions and selectivity were confirmed through H NMR, FT-IR spectroscopy, and density functional theory (DFT) calculations. NMA proved highly effective in diverse applications, including detecting Al in food samples, bioimaging in living cells, and environmental monitoring via smartphone-assisted platforms and test strips, making it a powerful tool for addressing aluminum toxicity in practical and real-time settings.