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.

Curcumin as a colorimetric and fluorescent chemosensor for selective recognition of fluoride ion

“…[10][11][12]. Presently, a number of compounds that were able to bind fluoride ion with high affinity and selectivity have been reported [13][14][15]; however, the challenges of selecting these receptors that would allow the naked-eye-detection of fluoride ion without resorting to any spectroscopic instrument still remain [16,17].…”

Two new indole derivatives as anion receptors for detecting fluoride ion

“…In particular, great effort has been devoted to the recognition of the fluoride ion, because it is highly relevant to environmental and health issues [5][6][7][8][9][10][11][12][13][14]. Several successful examples have been reported [15][16][17][18][19][20], e.g., the receptors based on the chemical affinity between fluoride and silicon can exhibit high selectivity for F À [21][22][23], but the rational design of F À receptors with remarkable fluorescent or colorimetric response is still a great challenge. One of the design strategies of fluoride receptors is based on the formation of a hydrogen bond between the fluoride ion and the active N-H group of an organic chromophore, which will result in a detectable change of spectral characteristicsof the chromophore upon the recognition of fluoride ion.…”

A New Luminescent Ruthenium(II) Polypyridine‐derived Dipicolylamine Complex as a Sensor for Cu2+ Ions

“…[4][5][6][7] However, few of them are based on heavy-metal complexes such as ruthenium complexes. 8 Compared with organic dyes, ruthenium complexes with low-lying excited states and long-wavelength emission behave as a promising class of luminescent sensors for analytes, including protons, 9 ions [10][11][12][13][14] and biomolecules, 15 because these advantages allow their luminescence easily separated from fluorescent backgrounds. It is well known that di(2-picolyl)amine (DPA) moiety in particular has been widely employed because of its specificity for Zn 2 ＋ over other metal ions.…”