Polyacrylamide gel electrophoretic preparation of labeled and non-labeled peptides for radioimmunoassay.

Radioiodinated polypeptide hormones, such as insulin, glucagon, human growth hormone, and human C-peptide are employed for radioimmunoassays for investigations of hormonal alterations in states of disturbed carbohydrate metabolism. Iodination was performed using chloramine T. Iodination products of these polypeptide hormones and, for preparation of standard material, native human C-peptide from cadaver pancreases were fractionated by polyacrylamide gel electrophoresis at pH 8.9. Disc electrophoresis in 24 cm-long gel rods resulted in stable tracers with high specific activity as well as homogeneous standard material being highly suitable for radioimmunoassays.