Turn-on Fluorescence Chemosensor for Zn2+ Ion Using Salicylate Based Azo Derivatives and their Application in Cell-Bioimaging.

The synthesis and optical studies of salicylate based azo derivatives (DPSAD and IPSAD) are reported. The receptors act as a versatile fluorogenic chemosensor for Zn2+ causing a selective enhancement of fluorescence over other competing cations. The complex formed between receptors and Zn2+ are identified on the basis of absorption and fluorescence titration and further confirmed by ESI-MS. DFT/TD-DFT calculations support the observed optical changes happens only upon complexation with Zn2+ ion. Moreover, receptors are further applied to intracellular sensing and imaging studies. Graphical Abstract Salicylate based azo derivatives (DPSAD and IPSAD) as fluorogenic chemosensor for the detection of Zn2+ ion.