Fluorescence based metabisulfite sensing: New aspects of ion sensing by a styryl benzothiazolium dye and understanding nitrite interference.

Detection of specific ions using fluorescent probes has relevance in several areas of therapeutics development and environmental science. Here, we provide new perspectives to the sensing of a styryl benzothiazolium-based fluorescent compound 1 and report that sensing properties are for sulfite ions in general with highest preference for metabisulfite ions (SO) adding to its previously determined role as a bisulfite ion sensor. This probe exhibits its sensing action via an addition reaction in which the styryl double bond gets reduced.