A novel zinc(II) and hydrogen sulphate selective fluorescent "turn-on" chemosensor based on isonicotiamide: INHIBIT type's logic gate and application in cancer cell imaging.

We have developed a novel isonicotiamide-based fluorescent "turn-on" chemosensor 1 for the selective detection of Zn(2+) and HSO4(-). The sensor 1 can detect Zn(2+) and HSO4(-) with a detection limit down to the nanomolar level by forming a complex in 1 : 1 stoichiometry in the presence of other anions and 2 : 1 in presence of cations in aqueous solution. Density functional theory calculations on 1 and the 1-Zn(2+)/HSO4(-) complexes are consistent with the experimental results. We have successfully utilized the above cation and anion for the fabrication of INHIBIT molecular logic gates. Furthermore the receptor 1 successfully detected the Zn(2+) and HSO4(-) ions in HeLa cells cultured in Zn(2+) and HSO4(-) enriched medium.