title: Radioiodinated derivatives for steroid radioimmunoassay. Application to the radioimmunoassay of cortisol.
abstract: Gamma-emitting steroid tracers for use in the radioimmunoassay of steroids have a number of advantages over the more common tritiated tracers. The steroid derivatives aldosterone3-(p-hydroxybenzoyl) hydrazone, aldosterone-3-(p-hydroxyphenylpropionyl)hydrazone, deoxycorticosterone-3-(p-hydroxyphenylpropionyl)hydrazone, and cortisol-3-(p-hydroxyphenylpropionyl)hydrazone were synthesized by a one-step procedure and iodinated ([125I]). To illustrate the usefulness of these derivatives, we describe the details of a cortisol radioimmunoassay. The use of the radioiodinated tracer appeared to increase the specificity of the antigen-antibody reaction when compared with [3H]cortisol. The methodology involved in the preparation of the steroid derivatives described above can be extended to other 3-oxo-4-ene-containing steroids, with the advantages of economy, simplicity, and versatility.
mesh_terms: D000450:Aldosterone / Q000031:analogs & derivatives* / Q000276:immunology; D003429:Cross Reactions; D003900:Desoxycorticosterone / Q000031:analogs & derivatives* / Q000276:immunology; D006854:Hydrocortisone / Q000031:analogs & derivatives / Q000032:analysis* / Q000276:immunology; D007457:Iodine Radioisotopes; D011849:Radioactive Tracers; D011863:Radioimmunoassay
chemical_list: D007457:Iodine Radioisotopes; D011849:Radioactive Tracers; D003900:Desoxycorticosterone; D000450:Aldosterone; D006854:Hydrocortisone