title: A radioimmunoassay of plasma unconjugated and conjugated estetrol.
abstract: A radioimmunoassay for the measurement of both unconjugated and conjugaged estetrol in plasma has been developed. The antiserum obtained after 6 months of immunization with 6-oxoestetrol-6-(O-carboxy-methyl)oxim-BSA was used at a final dilution of 1:90,000 and showed almost no cross reaction with other steroids except for estriol at 1.24%. Esterol-glucosiduronate was synthesized by incubating with adrenalectomized rat liver homogenate and uridine diphosphoglucuronic acid. Then, plasma estetrol-glucosiduronate was measured in the same manner for unconjugated estetrol after hydrolysis with beta-glucuronidase. Sephadex LH-20 column chromatography (7X110 mm, benzene:methanol, 85:15) was employed for accurate assessment. The sensitivity was 10 pg and the smallest amount measurable was 40 pg/sample. The method bland was consistently negligible. The intra and inter assay precision was 11.8% and 14.2% for unconjugated estetrol and that for estetrol-glucosiduronate was 13.5% and 17.1%.
mesh_terms: D000918:Antibody Specificity; D000936:Antigen-Antibody Complex; D003429:Cross Reactions; D004953:Estetrol / Q000097:blood*; D004964:Estriol / Q000031:analogs & derivatives*; D004966:Estrogens, Conjugated (USP) / Q000097:blood; D005260:Female; D005965:Glucuronates / Q000097:blood; D005966:Glucuronidase; D006801:Humans; D011247:Pregnancy; D011863:Radioimmunoassay / Q000379:methods; D014535:Uridine Diphosphate Glucuronic Acid
chemical_list: D000936:Antigen-Antibody Complex; D004966:Estrogens, Conjugated (USP); D005965:Glucuronates; D014535:Uridine Diphosphate Glucuronic Acid; D005966:Glucuronidase; D004953:Estetrol; D004964:Estriol