title: The development of a radioimmunoassay system for testosterone (T) and dihydrotestosterone (DHT). Part 3. The preparation of radioiodinated testosterone.
abstract: A two step-method was applied for the preparation of a tracer adequate for a radioimmunoassay (RIA) system for testosterone. Histamine was radioiodinated by the Chloramine-T method and then coupled to testosterone-3-carboxymethyl-oxime (T-3-CMO) derivative. After purification by TLC, the steroid tracer was stable in ethanol for at least four months. Using an anti-T-3-CMO-BSA serum, a (bridge) homologous RIA system for testosterone was developed. The reagents (antiserum, tracer and standard) were incubated 2 hrs at 37 degrees C and then the free radioactivity was removed by a dextran-charcoal suspension. The testosterone RIA system, with the sensitivity of 30 pg/tube, is suitable for the measurement of the steroid hormone in biological fluids and tissues.
authors.affiliation: C. I. Parhon Institute of Endocrinology, Bucharest, Romania.
authors.forename: E
authors.initials: E
authors.lastname: Neacşu
authors.forename: L
authors.initials: L
authors.lastname: Simionescu
authors.forename: A
authors.initials: A
authors.lastname: Zimel
authors.forename: A
authors.initials: A
authors.lastname: Caragheorgheopol
mesh_terms: D000818:Animals; D002855:Chromatography, Thin Layer; D013196:Dihydrotestosterone / Q000097:blood* / Q000276:immunology; D007457:Iodine Radioisotopes; D007553:Isotope Labeling / Q000379:methods; D008297:Male; D011817:Rabbits; D011863:Radioimmunoassay / Q000295:instrumentation / Q000379:methods*; D013739:Testosterone / Q000097:blood* / Q000276:immunology / Q000302:isolation & purification
chemical_list: D007457:Iodine Radioisotopes; D013196:Dihydrotestosterone; D013739:Testosterone