Zinc(II)-based fluorescent dyes: Luminescence modulation by phosphate anion binding

This review deals on the interaction of inorganic phosphate anions with zinc(II)-based luminescent dyes, with particular attention to the effects on their emission spectra observed upon binding of these anions to zinc(II). Interaction with phosphates induces different effects, including electron and charge transfer processes as well as structural rearrangements of the complex structures, which can remarkably change the photophysical properties of zinc(II)-based dyes. These effects have been exploited to develop luminescent systems for the selective recognition of inorganic phosphates, which are discussed on the basis of their structural architecture and mechanism involved in the sensing process triggered by the anion binding at the metal centre(s).