Transforming the recognition site of 4-hydroxyaniline into 4-methoxyaniline grafted onto a BODIPY core switches the selective detection of peroxynitrite to hypochlorous acid.

Two novel probes were designed, sharing the same BODIPY core but differing only by a minimized variation in the recognition site from 4-hydroxyaniline into 4-methoxyaniline. Such a small change in the reaction site could switch the selective detection from peroxynitrite to HOCl. Undoubtedly, the new designed BODIPY core exhibits valuable properties.