A biosensing application based on quenching the enhanced electrochemiluminescence of poly[tris(N-bipyridylethyl)pyrrole] ruthenium(II) film by Au nanoparticles

A new stable solid-state electrochemiluminescence (ECL) sensor was fabricated by electropolymerizing tris ((4-(2-pyrrol-1-ylethyl)-4′-methyl-2,2′-bipyridine) ruthenium(II) complex (denoted as Ru(L)3) upon glassy carbon electrode (GCE). Meanwhile, 3.5-fold enhanced ECL intensity of polyRu(L)3/GCE was obtained in H2O/CH3CN solvent instead of H2O. Interestingly, an obvious ECL quenching was observed by introducing gold nanoparticles onto the polymer film. Atomic force microscope (AFM) was used to characterize the obtained polyRu(L)3 film and nanogold seeds/polyRu(L)3 film morphologies. The electrochemical and ECL behaviors were investigated by cyclic voltammetry. Based on the efficient quenching, a new glucose ECL biosensor as a model was accomplished by in situ growing-up gold seeds in AuCl4- solution induced by biologically generated H2O2. The linear range to detect glucose is from 5.0 × 10−5 M to 2.0 × 10−3 M with the limit of detection of 2.5 × 10−5 M.

► Enhanced solid-state electrochemiluminescence of electropolymeric film, polyRu(L)3 was obtained in H2O/CH3CN.
► An obvious ECL quenching was observed by introducing gold nanoparticles onto the polymer film.
► A glucose ECL biosensor was accomplished by in situ growing-up gold seeds induced by biologically generated H2O2.