A Review on Fluorescent Chemosensors for Mercury (II) Ion: Mechanism and Applications

Abstract

Mercury (Hg) is reactive to different chemical species at different conditions and recycles within the organic phenomenon as well as bio-accumulated in animals including humans. This review generalizes the developments in fluorescent chemosensors for Hg2+. Fluorescent chemosensors are classified as; ratiometric, 'Off-On', and 'On-Off', considering fluorescent signal change and again these are further subdivided by considering structure and recognition means. Furthermore, Hg2+ promoted hydrolysis reaction-based chemosensor is also discussed. As compared to 'On-Off' and 'Off-On' types ratiometric fluorescent sensors are less affected by interference. Almost all chemosensors detect Hg2+ down to the maximum allowed limit set by EPA, but only some of them could be used to remove/separate Hg2+ from the solution. In addition, more of these chemosensors are not; environmentally friend, low cost, reversible, and biocompatible. Finally, detection means and applications of fluorescent chemosensors and upcoming opinions are overviewed clearly.