title: Spectrophotometric determination of H(2)O(2) with 1-anilinonaphthalene-8-sulfonic acid and 4-aminoantipyrine with hematin as catalyst.
abstract: A spectrophotometric flow injection method for the determination of H(2)O(2) in aqueous solution is presented. The technique is based on the oxidative condensation reaction between 1-anilinonaphthalene-8-sulfonic acid (ANSA) and 4-aminoantipyrine (AAP) in the presence of H(2)O(2). Hematin is a good peroxidatic catalyst for this reaction; its effectiveness is significantly enhanced in an ammoniacal medium. If the yellow product formed in the alkaline medium is acidified, a blue chromophore (lambda(max) 592 nm) is formed; a surfactant is necessary to keep the blue compound in solution. Chemical and instrumental parameters for FIA were evaluated and optimized. A detection limit of 0.3muM was achieved with a linear dynamic range extending to 50muM. The typical relative standard deviation is 1.5% or better. The structure of the reaction product has been identified.
authors.affiliation: Department of Chemistry, Texas Technical University, Lubbock, TX 79409-1061, U.S.A.
authors.forename: H K
authors.initials: HK
authors.lastname: Chung
authors.forename: P K
authors.initials: PK
authors.lastname: Dasgupta
authors.forename: J N
authors.initials: JN
authors.lastname: Marx