EXPERIENCES USING CHLORAMINE-T AND 1,3,4,6-TETRACHLORO-3-ALPHA,6-ALPHA-DIPHENYLGLYCOLURIL (IODOGEN) FOR RADIOIODINATION OF MATERIALS FOR RADIOIMMUNOASSAY

  • 1 January 1981
    • journal article
    • research article
    • Vol. 19  (10) , 1051-1056
Abstract
Labeling compounds with chloramine-T and with 1,3,4,6-tetrachloro-3.alpha.,6.alpha.-diphenylglycoluril (Iodogen) were compared. For human transferrin, human calcitonin, 1-84 bovine parathyrin, fibrinopeptide-A, human thyrotropin and F-CB3, a CNBr cleavage peptide of human fibrinogen, the quality of tracer produced by the Iodogen method was better. For rat lutropin, human growth hormone and human prolactin, labeling with Iodogen produced a tracer of unsatisfactory quality. For a further 13 peptides, the results from both methods were comparable. Optimal reaction times using Iodogen were 2-3 times longer than when using chloramine-T. Reduction of the volume of radioactive waste by up to 90% could be achieved when the Iodogen method was coupled with a short cation-exchange column to separate unreacted iodide from the labeled compound. Data are presented on the quality of tracer, expressed in terms of elution profiles and radioimmunoassay standard curves. A novel combi-method of labeling proteins without tyrosine or histidine moieties is presented where N-succinimidyl-3-(4-hydroxyphenyl)-propionate is labeled at pH 7.5 using Iodogen to give Bolton-Hunter reagent, which is then transferred to a vessel containing the peptide to be labeled at pH 8.6.