Stable lodinated polypeptide hormones prepared by polyacrylamide gel electrophoresis

Iodination of several insulin and proinsulin preparations, human growth hormone and bovine pancreatic polypeptide was performed using H₂O₂ and lactoperoxidase or chloramine T. The iodination mixtures were fractionated by polyacrylamide gel electrophoresis at pH 9.15 in long gel rods followed by simple elution of the iodinated products from thin gel slices. With this method ¹²⁵I tracers with long shelf life and high specific activity suitable for radioimmunoassays could easily be obtained.