title: A new ditopic ratiometric receptor for detecting zinc and fluoride ions in living cells.
abstract: The synthesis, characterization and ion binding properties of a new ditopic ratiometric receptor (1), based on 2-(4,5-dihydro-1H-imidazol-2-yl)phenol and crown ether moieties, have been described. The ditopic ratiometric receptor has been studied in sensing both F(-) and Zn(2+) ions, exhibiting different fluorescent colour changes from cyan green to blue/black observable by the naked eye under UV-light. The addition of Zn(2+) to the solution of 1 induced the formation of a 2 : 2 ligand-metal complex 1-Zn(2+), which displays a remarkable blue shift of the emission maxima of 1 from 455 nm to 400 nm due to the inhibition of excited-state intramolecular proton transfer (ESIPT) mechanism. The sensing processes were monitored by fluorescence/absorption titrations, and further confirmed by Job's plot and (1)H NMR titrations. The crystal structure of 1-Zn(2+) reveals that 1 binds Zn(2+) in four-coordinated modes. Furthermore, 1 is cell permeable and may be applied to detect trace Zn(2+) and F(-) during the development of a living organism.
authors.affiliation: Department of Chemistry, TKL of Metal and Molecule-based Material Chemistry, Synergetic Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China.
authors.forename: Ya-Ping
authors.initials: YP
authors.lastname: Li
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhao
authors.forename: Hua-Rong
authors.initials: HR
authors.lastname: Yang
authors.forename: Sui-Jun
authors.initials: SJ
authors.lastname: Liu
authors.forename: Xiu-Ming
authors.initials: XM
authors.lastname: Liu
authors.forename: Ying-Hui
authors.initials: YH
authors.lastname: Zhang
authors.forename: Tong-Liang
authors.initials: TL
authors.lastname: Hu
authors.forename: Jia-Tong
authors.initials: JT
authors.lastname: Chen
authors.forename: Ze
authors.initials: Z
authors.lastname: Chang
authors.forename: Xian-He
authors.initials: XH
authors.lastname: Bu
mesh_terms: D002470:Cell Survival; D043844:Crown Ethers / Q000737:chemistry; D018360:Crystallography, X-Ray; D005459:Fluorides / Q000032:analysis* / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D006860:Hydrogen Bonding; D006863:Hydrogen-Ion Concentration; D007093:Imidazoles / Q000138:chemical synthesis / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D013050:Spectrometry, Fluorescence / Q000379:methods*; D015032:Zinc / Q000032:analysis* / Q000737:chemistry*
chemical_list: D043844:Crown Ethers; D007093:Imidazoles; D015032:Zinc; D005459:Fluorides