Fluorescent Chemosensors Based on Polyamine Ligands: A Review

Polyamine ligands are water-soluble receptors that are able to coordinate, depending on their protonation degree, either metal ions, anionic, or neutral species. Furthermore, the presence of fluorescent signaling units allows an immediate visual response/signal. For these reasons, they can find applications in a wide variety of fields, mainly those where aqueous media is necessary, such as biological studies, wastewater analysis, soil contamination, etc. This review provides an overview of the recent developments in the research of chemosensors based on polyamine ligands functionalized with fluorescent signaling units. The discussion focuses on the design, synthesis, and physicochemical properties of this type of fluorescent chemosensors in order to analyze the applications associated to the sensing of metal ions, anions, and neutral molecules of environmental and/or biological interest. To facilitate a quick access and overview of all the chemosensors covered in this review, a summary table of the chemosensor structures and analytes, with all the corresponding references, is also presented.