Near infrared emitting electrochemiluminescent ruthenium polymer

摘要

A ruthenium polymer in which two complexes, [Ru(dp-phen)_2]~(2+) (RuN6) and [Ru(dp-phen)_2Cl]~+ (RuN5Cl), were bound to PVP polymer backbone was synthesized and characterized; dp-phen is 4,7 - diphenyl- 1,10-phenanthroline and PVP is poly(4-vinylpyri-dine). Polymer solution in acetonitrile has two photoluminescence emission peaks, one centered at 620 nm belonging to the RuN6 complex, and a second one at 720 nm corresponding to the RuN5Cl complex. In aqueous solutions and films only one peak centered at 720 nm is present, indicating efficient energy transfer from RuN6 to RuN5Cl centers. Electrochemiluminescence (ECL) is generated in two steps: first the RuN6 centers are oxidized and react with the analyte present, e.g. oxalate, to form an excited ruthenium species, and in the second step, the excited state energy is transferred to the lower energy RuN5Cl centers, which leads to the emission at 720 nm. We also investigated the possibility of ECL multiplex analysis of guanosine and 8-oxoguanosine.