Selective Fluorescence Quenching by Group 8 Metal Ions of a Water-Soluble Poly(p-phenylene vinylene) Derivative Bearing Oligo(oxyethylene) Pendants

A new fluorescing, water-soluble derivative of poly(p-phenylene vinylene), poly[2,5-bis-(oligooxyethylene)-1,4-phenylene vinylene], P(OE-PV), is synthesized via a multistep route. The UV-vis absorption and photoluminescence properties of the polymer are studied in aqueous solutions in the presence of 25 different metal ions. Among the ions studied, Fe(III), Os(III) and Ru(III) are found to effectively quench the fluorescence of P(OE-PV). The Ru(III) is the most efficient in the fluorescence quenching. This observation implies that the polymer is a sensitive and selective chemosensor for these ions. It is suggested that the photoinduced electron transfer from the excited state of P(OE-PV) to the metal ions may be the quenching mechanism application to the present systems.