Solvent dependent colorimetric, ratiometric dual sensor for copper and fluoride ions: Real sample analysis, cytotoxicity and computational studies

Abstract A novel colorimetric chemosensor based on terephthalic acid and pyridine aldehyde moiety was designed to detect Cu 2+ /F − ions in aqueous and DMSO solutions at physiological pH conditions with the detection limit of 0.25 μM and 3 μM for Cu 2+ /F − ions respectively. The probe was found to be highly selective to sense F − ion rather than CH 3 COO − and H 2 PO 4 − ions. Interestingly, the probe behaved as a promising receptor by detecting F − ions even in ordinary tap water through distinct colour change. Moreover, the chemosensor showed lower cytotoxicity against AGS cancer cells and thus found to be biologically friendly. The reversibility of probe-F − binding was investigated using HCl in UV–vis experiment. The binding mechanism of chemosensor to Cu 2+ /F − ions was elucidated based on the UV–vis spectroscopy, NMR, ESI-Mass spectroscopy and cyclic voltammogram techniques. Furthermore, theoretical investigation was carried out using Gaussian 09 program.