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 fluorescence spectroscopy. Strong fluorescent emission of the complex was observed at 593 and 616 nm upon the excitation of 300 nm. The fluorescent emission was quenched upon addition of trace amount of diethyl chlorophosphate (DCP). And the observed Ksv values for DCP were measured to be 0.568×103 and 0.89×103 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.