A highly sensitive benzimidazole-based chemosensor for the colorimetric detection of Fe(ii) and Fe(iii) and the fluorometric detection of Zn(ii) in aqueous media

Abstract

A new dual chemosensor 1 for the colorimetric detection of Fe 2+/3+ and the fluorometric detection of Zn 2+ has been developed and characterized. The sensor 1 has proven to be highly selective to Fe 2+/3+ with a color change from colorless to dark green in a near-perfect aqueous solution. 1 had low detection limits (1.21 mM for Fe 3+ and 1.18 mM for Fe 2+ ), which are lower than the World Health Organization guideline (5.36 mM) for drinking water. Moreover, 1 showed a selective detecting ability for Zn 2+ by 'OFF-ON' fluorescent response in aqueous solution. The detection limit (1.05 mM) of 1 for Zn 2+ was much lower than World Health Organization guideline (76 mM) for drinking water. Interestingly, it could be recycled simply through treatment with an appropriate reagent such as EDTA (ethylenediaminetetraacetic acid). The sensing mechanism of 1 for Zn 2+ was explained by the theoretical calculations. In particular, the sensor 1 could be used to quantify iron and zinc in water samples.

A Novel Thiophene-Based Fluorescent Chemosensor for the Detection of Zn2+ and CN−: Imaging Applications in Live Cells and Zebrafish

“…Thiophene derivatives have been extensively utilized as a fluorescence signaling promoter to anions, organic acids, and metal ions [40,41]. Moreover, 4-diethylaminosalicylaldehyde moiety is an outstanding fluorophore that has a water-soluble electron-donor property [42,43]. Thus, we combined the two functional groups to design a novel and practical fluorescent sensor, which is expected to sense a particular analyte through a unique fluorescent property with bioimaging ability in both living cells and zebrafish.…”

Hydrothermal synthesis of spindle-like $${\hbox {SrMoO}}_{4}{:}{\hbox {Ln}}^{3+}$$ (Ln = Eu and Tb) microarchitectures for selectively detecting $${\hbox {Fe}}^{3+}$$ ions

“…Furthermore, it reached a plateau when the concentration of the Fe 3+ ion was beyond 2.5 mM at the intensity of 543 nm (inset). Besides, the detection limit was calculated to be 1.12 × 10 −6 mol l −1 , and this facile method possesses equivalent sensitivity to some of the reported methods for Fe 3+ ion assay [36][37][38].…”

Novel benzimidazole-based conjugated polyelectrolytes: synthesis, solution photophysics and fluorescent sensing of metal ions

“…The sp 2 hybridized nitrogen atom on benzimidazole has a lone pair of electrons that can coordinate with metal ions, resulting in changes in optical properties to achieve the purpose of detection (21). Thus, there have been a number of reports about small molecule probes containing benzimidazole (22,23). Related studies on benzimidazolecontaining conjugated polymers reported in the past have mainly focused on light-emitting diodes (24) and photovoltaic devices (25).…”