title: Thiophene aldehyde-diamino uracil Schiff base: A novel fluorescent probe for detection and quantification of cupric, silver and ferric ions.
abstract: A new Schiff base from the condensation of 5,6-diamino-1,3-dimethyluracil with 5-methylthiophene-2-carboxaldehyde was synthesized. The compound was characterized by spectral data (UV-Vis, IR, (1)H NMR, fluorescence, MS). Ethanolic solutions of the Schiff base exhibit a strong fluorescence emission at 385 nm (λex=341 nm), and have been employed as a "turn-off" fluorescent probe for selective detection of Ag(+), Cu(2+) and Fe(3+) ions in presence of other cations such as Na(+), K(+), Ca(2+) and Mg(2+) ions abundant in natural water. The interaction between the tested compound and copper, silver or iron ions is associated with a significant fluorescence decrease, showing detection limits of 2.1-14.2 ppb. Under optimal conditions, the developed sensor was successfully employed to determine Ag(+), Cu(2+) and Fe(3+) ions in real samples and proved to be selective and sensitive.
authors.affiliation: Department of Chemistry, Faculty of Science, King Faisal University, Al-Ahsa 31982, Saudi Arabia; Department of Chemistry, Faculty of Science, Beirut Arab University, Debbieh, Lebanon. Electronic address: hhammoud@kfu.edu.sa.
authors.forename: Hassan H
authors.initials: HH
authors.lastname: Hammud
authors.affiliation: Department of Chemistry, Faculty of Science, Beirut Arab University, Debbieh, Lebanon.
authors.forename: Shawky
authors.initials: S
authors.lastname: El Shazly
authors.affiliation: Department of Chemistry, Faculty of Science, Beirut Arab University, Debbieh, Lebanon.
authors.forename: Ghassan
authors.initials: G
authors.lastname: Sonji
authors.affiliation: Department of Chemistry, Faculty of Science, Beirut Arab University, Debbieh, Lebanon.
authors.forename: Nada
authors.initials: N
authors.lastname: Sonji
authors.affiliation: Department of Chemistry, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon. Electronic address: kb05@aub.edu.lb.
authors.forename: Kamal H
authors.initials: KH
authors.lastname: Bouhadir
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D002412:Cations / Q000032:analysis; D003300:Copper / Q000032:analysis*; D003959:Diamines / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry*; D007501:Iron / Q000032:analysis; D057230:Limit of Detection; D008958:Models, Molecular; D012545:Schiff Bases / Q000737:chemistry*; D012834:Silver / Q000032:analysis*; D013050:Spectrometry, Fluorescence / Q000379:methods; D013876:Thiophenes / Q000737:chemistry*; D014867:Water / Q000032:analysis; D014877:Water Pollution, Chemical / Q000032:analysis*
chemical_list: D000447:Aldehydes; D002412:Cations; D003959:Diamines; D005456:Fluorescent Dyes; D012545:Schiff Bases; D013876:Thiophenes; D014867:Water; D012834:Silver; D003300:Copper; D007501:Iron
keywords: 5,6-Diamino-1,3-dimethyluracil; Ag(+)/Cu(2+)/Fe(3+) ions; Fluorescence probe; Methyl-2-thiophenecarboxaldehyde; Schiff base; Water pollution