title: Radioimmunoassay of triiodothyronine (T3) and thyroxine (T4). An assay with both the bound and free fraction of the hormone present in the counting vessel.
abstract: A radioimmunoassay for triiodothyronine T3 and thyroxine T4 without any manual separation is described. By the use of an aqueous two-phase system the free hormone was separated from the immunologically bound fraction and lifted out of the counting area of the gamma counter. The coefficient of correlation between results obtained with this method and with a conventional RIA was 0.97 and 0.93 for T3 and T4, respectively.
mesh_terms: D006801:Humans; D007106:Immune Sera; D011863:Radioimmunoassay / Q000379:methods; D013974:Thyroxine / Q000097:blood* / Q000302:isolation & purification; D014284:Triiodothyronine / Q000097:blood* / Q000302:isolation & purification
chemical_list: D007106:Immune Sera; D014284:Triiodothyronine; D013974:Thyroxine