Zinc ion detection using a benzothiazole-based highly selective fluorescence "turn-on" chemosensor and its real-time application.

A new photochromic fluorescence chemosensor was devised and effectively synthesized using benzothiazole and imidazopyridine derivatives. A "turn-on" fluorescence sensor BIPP for Zn(2+) detection was developed and has a quick response, excellent sensitivity, and remarkable selectivity over other metal ions. When Zn(2+) was added to the BIPP solution, a new strong fluorescence emission peak at 542 nm formed with a considerable increase in intensity. The fluorescence color of the BIPP solution changed from blue to bright green. The binding ratio 8 : 2 was found between BIPP and Zn(2+) by the results of Job's plot, HRMS and (1)H-NMR. The detection limit (LOD) of BIPP towards Zn(2+) was determined to be 2.36 × 10(-8), which is remarkably low. The ability to detect Zn(2+) in real water samples demonstrates that BIPP may also be used in environmental systems. Additionally, BIPP can be used to measure Zn(2+) levels in living cells.