title: Fluorescent sensing and selective Pb(II) extraction by a dansylamide ion-exchanger.
abstract: The (bis)dansylated sulfonamide 1,2-C6H4(NHSO2C10H6-5-N(CH3)2)2 (1) extracted Pb(II) selectively from water into 1,2-dichloroethane via an ion-exchange mechanism and showed fluorescence quenching upon Pb(II) extraction. The distribution ratios for metal extraction (determined by ICP-MS) for Pb(II) were 133-1410 times higher than those for other metal cations [Co(II), Ni(II), Cu(II), Zn(II), and Cd(II)] under identical conditions. Fluorescence quenching was observed upon Pb(II) extraction, which was dependent on Pb(II) concentration. The monodansylated control, C6H5NHSO2C10H6-5-N(CH3)2 (2), showed neither extraction nor quenching, indicating that the fluorescence effects are a direct result of Pb coordination to 1. The observed selectivity for Pb(II) is ascribed to the formation of a low-coordinate binary Pb(II)-Sulfonamido complex in the organic phase.
authors.affiliation: Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, FL 33199, USA.
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Kavallieratos
authors.forename: Jay M
authors.initials: JM
authors.lastname: Rosenberg
authors.forename: Wei-Zhong
authors.initials: WZ
authors.lastname: Chen
authors.forename: Tong
authors.initials: T
authors.lastname: Ren
mesh_terms: D002413:Cations, Divalent; D003619:Dansyl Compounds / Q000737:chemistry*; D005025:Ethylene Dichlorides / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry*; D007854:Lead / Q000737:chemistry / Q000302:isolation & purification*; D009566:Nitrates / Q000737:chemistry / Q000302:isolation & purification; D013050:Spectrometry, Fluorescence; D014867:Water / Q000737:chemistry
chemical_list: D002413:Cations, Divalent; D003619:Dansyl Compounds; D005025:Ethylene Dichlorides; D005456:Fluorescent Dyes; D009566:Nitrates; D014867:Water; C001026:5-dimethylaminonaphthalene-1-sulfonamide; D007854:Lead; C024565:ethylene dichloride; C017461:lead nitrate