title: A selective, nontoxic, OFF-ON fluorescent molecular sensor based on 8-hydroxyquinoline for probing Cd(2+) in living cells.
abstract: In spite of the fact that cadmium(II) has been recognized as a highly toxic element and that excessive exposure to this metal ion has been reported to have many adverse effects on human health, very few selective and specific fluorescent probes are available for imaging Cd(2+) in living cells. Herein, we report the spectroscopic and photochemical characterization of 5-(5-chloro-8-hydroxyquinolinylmethyl)-2,8-dithia-5-aza-2,6-pyridinophane (L) as a fluorescent sensor for the selective imaging of Cd(2+) in living cells. In particular, the response of L to Cd(2+) was first assessed in aqueous solutions, sodium dodecyl sulfate micelles, and liposomes, and subsequently in living cells by fluorescence microscopy techniques. Cytofluorimetric analyses of leukemic HL-60 cells loaded with L also allowed evaluation of the toxicity of the probe and the selective analysis of its intracellular fluorescence in the presence of Cd(2+). Furthermore, the 1:1 complex species [Cd(L)H(2)O](2+) responsible for the OFF-ON chelation enhancement of fluorescence (CHEF) effect on L was structurally characterized; time-dependent DFT calculations allowed the prediction of theoretical excitations, which were comparable with the experimental ones.
authors: Dipartimento di Chimica Inorganica ed Analitica, S.S. 554 Bivio per Sestu, Università degli Studi di Cagliari, 09042 Monserrato, CA, Italy.
authors: Marta
authors: M
authors: Mameli
authors: M Carla
authors: MC
authors: Aragoni
authors: Massimiliano
authors: M
authors: Arca
authors: Claudia
authors: C
authors: Caltagirone
authors: Francesco
authors: F
authors: Demartin
authors: Giovanna
authors: G
authors: Farruggia
authors: Greta
authors: G
authors: De Filippo
authors: Francesco A
authors: FA
authors: Devillanova
authors: Alessandra
authors: A
authors: Garau
authors: Francesco
authors: F
authors: Isaia
authors: Vito
authors: V
authors: Lippolis
authors: Sergio
authors: S
authors: Murgia
authors: Luca
authors: L
authors: Prodi
authors: Anna
authors: A
authors: Pintus
authors: Nelsi
authors: N
authors: Zaccheroni
mesh_terms: D000818:Animals; D019556:COS Cells; D002104:Cadmium / Q000737:chemistry* / Q000633:toxicity; D002460:Cell Line; D002614:Chelating Agents / Q000737:chemistry; D002522:Chlorocebus aethiops; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry; D018360:Crystallography, X-Ray; D005434:Flow Cytometry; D005456:Fluorescent Dyes / Q000737:chemistry*; D018922:HL-60 Cells; D006801:Humans; D008081:Liposomes / Q000737:chemistry; D008823:Micelles; D008856:Microscopy, Fluorescence; D008968:Molecular Conformation; D015125:Oxyquinoline / Q000737:chemistry*; D017319:Photosensitizing Agents / Q000138:chemical synthesis / Q000737:chemistry; D013816:Thermodynamics
chemical_list: D002614:Chelating Agents; D056831:Coordination Complexes; D005456:Fluorescent Dyes; D008081:Liposomes; D008823:Micelles; D017319:Photosensitizing Agents; D002104:Cadmium; D015125:Oxyquinoline