Novel fluorene-based chemodosimeters for mercury and methylmercury species in aqueous media

Four novel compounds 1a-4a consisting of fluorene as signaling unit and thiourea as responding unit were developed as fluorescent chemodosimeters for mercury and methylmercury species. Upon treatment with Hg2+ and CH3Hg+, the fluorescence of 3a is effectively quenched, whereas 1a, 2a and 4a show evident fluorescent color variations under illumination with 365 nm light: yellow to pale blue, yellow to bright blue, light red to orange yellow, respectively. They all exhibit specific sensitivity and selectivity for Hg2+ and CH3Hg+ over other examined metal ions in CH3CN-H2O solution at room temperature. (C) 2012 Elsevier B.V. All rights reserved.