Chalcogen-based fluorescent probes for metal ion detection: Principles, applications, and design strategies

Metal ion detection is notably significant in fields such as the biological sciences, clinical medicine, environmental chemistry, and food safety. In this regard, fluorescent probes have represented an important technique for the rapid detection of metal ions in various areas. As Lewis bases, chalcogen elements with high electrondonating ability provide versatile detection targets for metal ion fluorescent probes. Such probes with chalcogens serving as recognition sites can be classified into coordination- and reaction-type devices. Notably, thiols; sulfides; thiocarbonyls; S-containing crown ethers, aromatic hydrocarbons, and peptides; and Se/Te-containing ligands can all serve as detection sites for these probes. O/N-containing ligands for coordination, fluorophores, and linkers all affect the electron-donating ability and selectivity of the coordination system. In this review, we discuss ongoing research efforts in this area and propose some design strategies for introducing chalcogen elements into metal ion fluorescent probes by integrating Lewis acid-base theory and comparative studies.