title: Electrochemiluminescence of Tris(2,2'-bipyridine)ruthenium in Water at Carbon Microelectrodes.
abstract: Electrochemiluminescence (ECL) of Ru(bpy)(3)(2+) in water only, without any added electrolyte or reducing agents, has been obtained at carbon interdigitated microelectrode arrays (C-IDAs) of 2 μm width and spacing. In a generation/collection biasing mode, ECL can be clearly seen with the naked eye in normal room lighting at concentrations greater than 1 mM. Using a conventional photomultiplier tube (PMT), a detection limit of 10(-)(7) M Ru(bpy)(3)(2+) has been achieved for an electrode area of 0.25 mm(2). In comparison, the ECL intensity produced at Pt-IDA of the same geometry, under identical experimental conditions, was more than 300 times less. The ECL obtained at C-IDAs is attributed to the annihilation reaction of the reduced and oxidized forms of the Ru(bpy)(3)(2+) made possible due to the small electrode spacing.
authors.affiliation: Institute of Microtechnology, University of Neuchatel, 2007 Neuchatel, Switzerland, and Department of Electrical and Computer Engineering, University of California, Davis, California 95616.
authors.forename: G C
authors.initials: GC
authors.lastname: Fiaccabrino
authors.forename: M
authors.initials: M
authors.lastname: Koudelka-Hep
authors.forename: Y T
authors.initials: YT
authors.lastname: Hsueh
authors.forename: S D
authors.initials: SD
authors.lastname: Collins
authors.forename: R L
authors.initials: RL
authors.lastname: Smith