Photoelectroanalytical chemistry: possible interferences in serum and the selective detection of tris(2,2'-bipyridine)ruthenium(II) in the presence of interferents.

Photoelectroanalytical chemistry, the application of photoelectrochemistry to analysis, as reported here, is based on the amperometric detection of tris(2,2'-bipyridine)ruthenium(III) after its production from the corresponding Ru(II) complex in an excited state and quenching by electron transfer. The Ru(II) complex is detectable in concentrations less than 10(-10) mol/L injected into a flow stream in 100 microL. The selectivity of the detection is based upon several competitive reactions and their rates. The complex can be detected accurately in the presence of at least 10(4) molar excess of the potent interferents uric acid and oxalic acid. We anticipate that this complex will be used in assays that involve the use of labels.