title: Kinetic determination of carbimazole, methimazole and propylthiouracil in pharmaceuticals, animal feed and animal livers.
abstract: Kinetic methods are proposed for the determination of carbimazole(CBZ), methimazole(MMI) and propylthiouracil(PTU) based on their inhibitory effects on the palladium(II)-catalysed reaction between the pyronine G and hypophosphite ions. The reactions are monitored spectrophotometrically at 548 nm. The influence of reaction variables and the interfering effect of other substances were studied. Under the selected experimental conditions (CBZ: 3.6 x 10(-5) mol l-1 pyronine G; pH 3.0; 0.7 microgram ml-1 PdII and 0.2 mol l-1 H2PO2-; MMI: 6 x 10(-5) mol l-1 pyronine G, pH 3.0; 0.7 microgram ml-1 PdII, 0.4 mol l-1 H2PO2-; PTU: 3.6 x 10(-5) mol l-1 pyronine G; pH 3.0; 0.7 microgram ml-1 PdII and 0.3 mol l-1 H2PO2-), these three antithyroids were determined in the following ranges: CBZ, 0.04-0.70 microgram ml-1; MMI, 0.04-0.50 microgram ml-1; PTU 0.08-1.00 microgram ml-1. The methods were applied to the determination of CBZ, MMI and PTU, in pharmaceuticals, animal feed and animal livers.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University of Murcia, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Soledad García
authors.forename: M I
authors.initials: MI
authors.lastname: Albero
authors.forename: C
authors.initials: C
authors.lastname: Sánchez-Pedreño
authors.forename: L
authors.initials: L
authors.lastname: Tobal
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D016477:Artifacts; D002231:Carbimazole / Q000032:analysis*; D007700:Kinetics; D008099:Liver / Q000737:chemistry*; D008713:Methimazole / Q000032:analysis*; D004364:Pharmaceutical Preparations / Q000032:analysis*; D011441:Propylthiouracil / Q000032:analysis*; D013057:Spectrum Analysis
chemical_list: D004364:Pharmaceutical Preparations; D008713:Methimazole; D011441:Propylthiouracil; D002231:Carbimazole