A highly sensitive fluorescent chemosensor for simultaneous determination of Ag(I), Hg(II), and Cu(II) ions: Design, synthesis, characterization and application

Using calculations of the electronically excited states for investigation of fluorescent sensors: A review

“…[46,47] Calculations of the electronically excited states based on the optimized geometry of the ground state are also used to explain changes in fluorescence properties in cases where there is the charge or electron transfer between ligands and metal ions, such as the metal to ligand charge transfer (MLCT) or the ligand to metal electron transfer (LMET), and the ligand to metal charge transfer (LMCT) or the metal to ligand electron transfer (MLET). [13,22] For developing the fluorescent sensor 6 based on 4-N, N-dimethylaminocinnamaldehyde as a fluorophore for detection of Hg(II), Cu(II) and Ag(I) ions ( Figure 6), [13] based on the results obtained from calculations of the electronically excited states, Quang and co-workers have set up the frontier MOs energy diagrams of sensor 6 and its complexes with metal ions to explain the changes in fluorescence intensity of these compounds. [13] For Ag(I) complex ( figure 7), the complexation causes the ligand to metal electron transfer (LMET).…”

“…[13,22] For developing the fluorescent sensor 6 based on 4-N, N-dimethylaminocinnamaldehyde as a fluorophore for detection of Hg(II), Cu(II) and Ag(I) ions ( Figure 6), [13] based on the results obtained from calculations of the electronically excited states, Quang and co-workers have set up the frontier MOs energy diagrams of sensor 6 and its complexes with metal ions to explain the changes in fluorescence intensity of these compounds. [13] For Ag(I) complex ( figure 7), the complexation causes the ligand to metal electron transfer (LMET). As a result, the electron density of MOs from MO-131 to MO-140 (HOMO) is mainly distributed at the metal ion.…”

“…[10][11][12] However, if the fluorescent sensor participates irreversibly with a specific analyte, then it is called a chemodosimeter. [13][14][15] The first fluorescent sensor based on spirolactam ring-opening process of rhodamine B derivative for the detection of Cu(II) ions was reported by Czarnik in 1992. [16] The publications of new fluorescent sensors have been rapidly increased since 2005.…”

A selective sulphur‐containing colorimetric chemosensor for Cu2+

“…To meet the demand of colorimetric sensors that can detect easily and rapidly copper, we designed the chemosensor APTS (Scheme 1), which contains sulphur in its structure. Sulphur is well known to have a high affinity to Cu 2+ , Ag + and Hg 2+ , and a number of sulphur‐containing sensors have been reported to detect the three metals . In order to selectively detect only Cu 2+ among them, we endowed the sensor APTS with a hard character by using moieties with nitrogen and oxygen atoms .…”

“…Sulphur is well known to have a high affinity to Cu 2+ , Ag + and Hg 2+ , and a number of sulphur-containing sensors have been reported to detect the three metals. [29][30][31][32] In order to selectively detect only Cu 2+ among them, we endowed the sensor APTS with a hard character by using moieties with nitrogen and oxygen atoms. [33][34][35][36] As expected, the sensor APTS detected only Cu 2+ via the colour change from colourless to yellow.…”