부산대학교 도서관

The present communication reports the efficacy of a salicylidene-isoniazide Schiff base based donor-π-acceptor (D-π-A) chemosensor (L1) for chromogenic and fluorogenic dual mode sensing of Al3+ and AsO2− in water rich semi-aqueous solution. L1 offers multiple benefits of simplicity, ease of synthesis, inexpensive, suitable binding sites for cations and anions, high sensitivity, noteworthy colourimetric response, naked-eye detection, selectivity, and good detection limits of 1.89 μM for Al3+ and 2.2 μM for AsO2−. It shows selective turn-on fluorescence response for both Al3+ and AsO2−, attributed to CHEF due to the combined effect of arrest of PET, inhibition of –CHN– geometrical isomerization, prevention of ESIPT process and increase in conformational rigidity. Owing to specific interaction between Mo(VI) and arsenite, L1-Mo(VI) ensemble system is successfully utilized for colourimetric detection of arsenite through displacement approach. The binding modes of the receptor L1 to these analytes are established through Job’s plot and 1H NMR spectroscopic analysis. The reversible off–on–off fluorescence switching behaviour of L1 upon binding to Al3+ and AsO2− are applied to construct combinational OR, AND, and NOT molecular logic gates. Fluorescence turn-on sensing, cell permeability and low toxicity of the chemosensor allows monitoring of these analytes in living cells.