A new nitrile vinyl linked ultrafast receptor to track cyanide ions: Utilization on realistic samples and HeLa cell imaging

[Display omitted] •A facile receptor PBTA [2E,2′E)-3,3′-(10-octyl-10H-phenothiazine-3,7-diyl)bis(2-(benzo[d]thiazol-2-yl)acrylonitrile] was successfully designed which shows fast response towards CN− with an excellent absorbance and emission properties.•The receptor PBTA detects CN− based on nucleophilic addition mechanism with lowest LOD and LOQ.•The receptor PBTA monitors CN− with suitable physiological pH (4–11) and also shows specific selectivity even in presence of other competitive ions.•The receptor PBTA was utilized to detect CN− present in the water samples, cyanogenic food plants and in live HeLa cells. A simple D − A (donor − acceptor) type receptor ((2E, 2′E)-3, 3′-(10-octyl-10H-phenothiazine-3,7-diyl)bis(2-(benzo[d]thiazol-2-yl)acrylonitrile)) (PBTA) containing nitrile-vinyl linkage was designed and completely characterized. The receptor PBTA detects CN− ions based on “turn-off” effect with admirable spectral properties. It also owns some of the merits like “naked-eye” color change, ultrafast response (90 s), lowest detection limit (1.25 × 10-10 M) as well as quantitation limit (4.17 × 10-10 M) with the pH range 4–11 which is more suitable pH to make use of the receptor PBTA in physiological medium. The instant detecting ability of the receptor over CN− ions was proved using paper test strip and cotton balls. Further, the utilization of the receptor PBTA was also extended to track CN− ions in realistic samples (water and food samples) and in HeLa cells bioimaging.