A Near-Infrared Fluorescence Chemosensor Based on Isothiocyanate-Aza-BODIPY for Cyanide Detection at the Parts per Billion Level: Applications in Buffer Media and Living Cell Imaging.

A near-infrared chemodosimeter based on an aza-BODIPY dye was designed and synthesized. The sensor contains isothiocyanate groups for cyanide ion sensing. The sensing function was illustrated via the fluorescence changes in near-infrared frequencies as well as chromogenic changes which could be easily visualized with a detection limit of 19 ppb. The sensor provides high selectivity to CN- and discriminates other anions such as CH3 COO- , HPO4- , HSO4- , ClO3- , CO32- , SO42- , NO3- , Cl- , F- , Br- , I- , and phenylalanine (Phe) in 50 % PBS buffer/acetonitrile at physiological pH. The potential of the sensor for CN- detection in both aqueous buffer solutions and living cells imaging was demonstrated.