Synthesis and fluorescent properties of a novel europium（III） complex with terpyridine-capped poly（ethylene glycol）

Terpyridine-capped poly（ethylene glycol） （PEG） was synthesized as a novel polymeric ligand and rare earth complex was prepared from Eu（NO3）3 and the telechelic macromolecules. The structure of the complex was characterized by 1H NMR, FT-IR, UV-vis and fluores-cence spectroscopy. Strong fluorescent emission of the complex was observed at 593 and 616 nm upon the excitation of 300 nm. The fluo-rescent emission was quenched upon addition of trace amount of diethyl chlorophosphate （DCP）. And the observed Ksv values for DCP were measured to be 0.568×10^3 and 0.89×10^3 L/mol for quenching at 593 and 616 nm, which indicated the detection limit for DCP was about 0.014 mmol/L. These results showed that the terpyridine-lanthanide complex could be an effective chemosensor with a potential application in the detection of organophosphates.