Small molecule sensors for the colorimetric detection of Copper(II): A review of the literature from 2010 to 2022

Small molecules can display certain electronic and structural features that enable their use for metal-sensing applications in different fields. Of the reported metal sensors, there has been increasing interest in copper sensing in the past decade, given the biological importance of copper as well as its presence as a potential contaminant in water and fuels. Molecules used for copper(II) sensing generally consist of a fluorophore/chro-mophore and a ligand for selective metal ion recognition. This review article focuses on literature contributions since the year 2010 concerning small molecule copper(II) sensors that provide a naked-eye color response in solution. We present molecular structural features and sensing mechanisms for the colorimetric and fluorometric detection of copper(II) ions in different environmental, agricultural, and biological samples. In addition, the sensing performance of these chemosensors is compared and discussed, which could aid in the future design of chemosensors for copper(II). Finally, we outline the challenges and future prospects of fluorophore/chromo-phore-ligand chemistry in applications of small molecules for fluorometric and colorimetric assays of copper(II).

Automated summary

Small molecules with specific electronic and structural features are being used for metal-sensing applications in various fields. Copper sensing has gained increasing interest in the past decade due to its biological importance and potential contamination in water and fuels. This review focuses on small molecule copper(II) sensors that exhibit color changes in solution. The article presents the molecular structures, sensing mechanisms, and performance of these sensors in different environmental, agricultural, and biological samples. The challenges and future prospects of using fluorophore/chromophore-ligand chemistry for fluorometric and colorimetric assays of copper(II) are also discussed.