title: Effect of pH on the reaction of tris(2,2'-bipyridyl)ruthenium(III) with amino-acids: Implications for their detection.
abstract: A new technique for the detection of amino-acids is described, which is based on their chemiluminescence reaction with tris(2,2'-bipyridyl)ruthenium(III). The pH-dependence of this reaction has been investigated and found to be the key experimental parameter in application of this reaction as a detection technique. The chemiluminescence emission obtained is maximal at pH values higher than the N-terminal amino group pK(a) of the amino-acid. The background reaction between the ruthenium reagent and hydroxide ion does not occur with the same efficiency as the amino-acid reaction and the optimum signal to noise ratio is obtained at pH 10. A limit of detection of 30 picomole was found for valine and the response was shown to be linear over two orders of magnitude.
authors.affiliation: Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, U.S.A.
authors.forename: S N
authors.initials: SN
authors.lastname: Brune
authors.forename: D R
authors.initials: DR
authors.lastname: Bobbitt