Ratiometric/‘On–Off’ sensing of Pb2+ ion using pyrene-appended calix[4]arenes

Bis(spirolactam) 1,3-double-armed calix[4]arene compounds and their application as extractants for the determination of heavy metal ions

“…N, S, Se and P [31]. Calixarenes with azo and imine units have shown good binding towards metal ions such as Ca 2+ and Ni 2+ , respectively [32][33][34]. In more recent years a number of calixarene derivatives containing thioether, pyridyl, benzothiazoyl and other heteroatomic…”

Dual‐Mode Calixarene‐Based Chemosensor: Highly Selective Fluorogenic Detection of Hg2+ and Chromogenic Detection of Cu2+ with a Single Ionophore

“…Several instrument‐based techniques are available for the detection of these metal ions, but it requires a costly instrument, highly skilled operator and tedious sample preparation methods and sometimes some of these techniques are not suitable for low concentration of metal ion , . As an alternative, in recent years fluorescent and colourimetric sensors have attracted much attention because of the advantages of ease of detection, high sensitivity and instantaneous response , , , . For Hg 2+ ion, various fluorescent probes have been reported incorporating photoactive organic and inorganic molecules as a fluorogenic unit and macrocyclic moieties such as aza‐crown ethers, calix[4]arenes, and cyclams as ionophores .…”

A switch‐off fluorescence probe towards Pb(II) and cu(II) ions based on a calix[4]pyrrole bearing amino‐quinoline group

“…Fluorophores that sense Pb(II) and Cu(II) ions have been developed. Kumar et al reported the use of a fluorescence detector for Pb(II) ions using N ‐(pyrenyl‐1‐methylimine)‐derivatized calix[4]arene . Ozlemshahin et al also reported the use of a fluorescence sensor using calix[4]arene derivatives that possess a pyrene amine moiety towards Pb(II) and Cu(II) ions .…”

“…[48] Long-time exposure to lead causes abdominal pain, and the presence of heavy metal ions such as Pb(II) in the environment at elevated levels causes health-related problems such as anaemia, a disorder of the blood, kidney damage, muscle paralysis and mental retardation as it is toxic to the bodies of both adult and children. [49] Copper is also a highly sensed ion due to its wide application in the body and in industry. It is one of the most abundant metals and is ranked as the third metal required in body.…”