Fluorescence Turn-on Sensory Compounds and Polymers for the Detection of Lead Ion in Water.

摘要

The goal of this thesis work is to synthesize a new type of fluorescence turn off-on sensory compounds and polymers for the detection of Pb2+ in aqueous medium. A sensory molecule was designed to have fluorene as a fluorophore and also as the building block for making a polymer. A new type of fluorescence turn-on sensory compound was successfully synthesized and characterized by IR, 1H-NMR, 13C-NMR and mass spectrometry. The sensory polymer was synthesized by the Yamamoto coupling reaction and characterized.;The sensory polymer is soluble in water when it exits in the salt form and shows a high sensitivity towards Pb2+. In its acid form the polymer is soluble in DMF and displays a relatively low sensitivity towards Pb2+. With further modification of polymer structures, such as by copolymerization with other fluorescent or non-fluorescent monomers, the resulting sensory polymers could be used in fibre-optic sensor for detection of lead ion in water.;The water-soluble sensory compound shows a high sensitivity and selectivity towards Pb2+ in aqueous medium. The fluorescence turns on when the Pb2+ ion binds with the sensory compound. The bromo-containing sensory compound shows the quenching effect of the bromine on fluorescence.