title: A micromethod for quantitative determination of iodoamino acids in thyroglobulin.
abstract: We describe a new method for quantification of iodoamino acids after enzymatic hydrolysis of thyroglobulin. The procedure involves separation of monoiodotyrosine (MIT), di-iodotyrosine, tri-iodothyronine and thyroxine by reverse phase HPLC with a Vydac C18 stationary phase and a mobile phase of water-acetonitrile-acetic acid. The separation is monitored by sensitive spectrophotometric detection through a 96-well microplate system based on the catalytic Sandell-Kolthoff reaction of iodide on the oxidation of arsenic(III) by cerium(IV). This new microassay is particularly convenient because of its high sensitivity and its rapidity (less than 2 h). It can detect 1 pmol MIT and 0.5 pmol of the other three iodoamino acids with a recovery higher than 96%. Moreover, the 96-well microplate system allows many samples to be tested simultaneously and avoids the use of radiolabeled iodine.
authors.affiliation: Unité 38 INSERM, Faculté de Médicine, Marseille, France.
authors.forename: N
authors.initials: N
authors.lastname: Baudry
authors.forename: B
authors.initials: B
authors.lastname: Mallet
authors.forename: P J
authors.initials: PJ
authors.lastname: Lejeune
authors.forename: L
authors.initials: L
authors.lastname: Vinet
authors.forename: J L
authors.initials: JL
authors.lastname: Franc
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004105:Diiodotyrosine / Q000032:analysis; D007470:Monoiodotyrosine / Q000032:analysis; D013552:Swine; D013954:Thyroglobulin / Q000737:chemistry*; D013963:Thyroid Hormones / Q000032:analysis*; D013974:Thyroxine / Q000032:analysis; D014284:Triiodothyronine / Q000032:analysis
chemical_list: D013963:Thyroid Hormones; D014284:Triiodothyronine; D004105:Diiodotyrosine; D013954:Thyroglobulin; D007470:Monoiodotyrosine; D013974:Thyroxine