Azo dyes featuring a pyrene unit: New selective chromogenic and fluorogenic chemodosimeters for Hg(II)

Three new chemodosimeters 1–3 were prepared, and their chromogenic and fluorogenic behaviors toward various metal cations were investigated. Receptors 1–3 show exclusive response toward Hg2+ ion and also distinguish Hg2+from other metal cations by different color changes in DMSO aqueous solution (DMSO/H2O = 9/1). Among them, receptor 1 also exhibits a pronounced Hg2+-induced fluorescence enhancement. Thus, the receptor 1 can be used as a colorimetric and fluorescent chemodosimeter for the determination of Hg2+ ion. The use of the test strip of the receptor 1 to detect Hg2+ was also reported.