title: High sensitive competitive immunodetection of 2,4-dichlorophenoxyacetic acid using enzymatic amplification with electrochemical detection.
abstract: The amplification cycle consisting of NADH independent oligosaccharide dehydrogenase (ODH) and laccase has been recently reported to be highly sensitive to several catecholamines and p-aminophenol. A competitive immunoassay for 2,4-dichlorophenoxyacetic acid has been developed by combining this amplification cycle with beta-galactosidase as enzyme label resulting in p-aminophenol as product. The combination of enzymatic amplification cycles with a competitive immunoassay yields a highly sensitive measurement of 2,4-dichlorophenoxyacetic acid. Using a monoclonal antibody the linear range of the assay was between 0.02 and 100 ng/l and the c(50) was found at 0.2 ng/l; the detection limit was at 5 pg/l (25 fmol/l) corresponding to 5 amol.
authors.affiliation: Analytical Biochemistry, Institute for Biochemistry and Molecular Physiology, University of Potsdam, c/o MDC Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Strasse 10, D-13122, Berlin-Buch, Germany.
authors.forename: F F
authors.initials: FF
authors.lastname: Bier
authors.forename: E
authors.initials: E
authors.lastname: Ehrentreich-Förster
authors.forename: C G
authors.initials: CG
authors.lastname: Bauer
authors.forename: F W
authors.initials: FW
authors.lastname: Scheller