A reversible and efficient probe for dual mode recognition of Al3+ and Cu2+ with logic gate behaviour: Crystal structure, theoretical and in-vivo bio-imaging investigations

This work presents the synthesis, characterization, crystal structure and spectroscopic investigations of isophthalohydrazide based probe. Among various tested metal ions, the probe selectively detects Al3+ and Cu2+ in aqueous ethanol via fluorometric and colorimetric methods, respectively. It displays a fluorescence turn-on response with Al3+ and visual colour change from colourless to yellow with Cu2+. Sensing mechanism is explored with UV-Vis, fluorescence spectroscopy and H-1 NMR titration, and confirmed with computational results. Suppression of C=N isomerization and photo-induced electron transfer (PET) along with chelation enhanced fluorescence emission (CHEF) result in turn-on fluorescence with Al3+ while ligand to metal charge transfer (LMCT) accounts for visual colour change with Cu2+. Job's plot and HRMS confirm 1:2 (L:M) stoichiometry. The probe also exhibits efficient reversibility and reproducibility with EDTA which are successfully mimicked with combinatorial logic gate and truth table. Additionally, solid state applications and bio-imaging investigation on gut tissue of Drosophila 3rd instar larvae are performed. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

This work presents the synthesis, characterization, crystal structure and spectroscopic investigations of isophthalohydrazide based probe. The probe selectively detects Al3+ and Cu2+ in aqueous ethanol via fluorometric and colorimetric methods. Sensing mechanism is explored with UV-Vis, fluorescence spectroscopy and H-1 NMR titration, and confirmed with computational results.