title: A highly selective chromo- and fluorogenic dual responding fluoride sensor: naked-eye detection of F- ion in natural water via a test paper.
abstract: A highly selective and sensitive chromogenic and fluorogenic dual signal responding fluoride-sensor 1, comprising a Ru-bipy fluorophore (bipy = 2,2'-bipyridine) and a 2,4-dinitrophenylhydrazone chromophore was prepared and spectroscopically characterized. Uv-vis titrations with F- revealed the appearance of a new intense absorption band centered at about 580 nm which was accompanied by a dramatic change in color from yellow to magenta, with the association constant logK being 6.71 +/- 0.04. Fluorescence spectra showed that upon addition of F-, the emission intensities enhanced significantly without any change in the excited and emission wavelengths, suggesting a potential photoinduced electronic transfer (PET) signaling transduction mechanism. An easy-to-prepare test paper which was obtained by putting a filter paper into an acetonitrile solution of 1, can detect F- in aqueous media, indicating the potential application for detecting F- in natural aqueous environments without any spectroscopic instrumentation. Spectroscopic titrations of the free ligand were also studied for comparison.
authors.affiliation: Coordination Chemistry Institute, State Key Laboratory of Coordination Chemistry, Nanjing 210093, P. R. China.
authors.forename: Zhi-hua
authors.initials: ZH
authors.lastname: Lin
authors.forename: Yong-gang
authors.initials: YG
authors.lastname: Zhao
authors.forename: Chun-ying
authors.initials: CY
authors.lastname: Duan
authors.forename: Bing-guang
authors.initials: BG
authors.lastname: Zhang
authors.forename: Zhi-ping
authors.initials: ZP
authors.lastname: Bai