RADIOLABELING OF HUMAN HEMOGLOBIN USING THE I-125 BOLTON-HUNTER REAGENT IS SUPERIOR TO OXIDATIVE IODINATION FOR CONSERVATION OF THE NATIVE STRUCTURE OF THE LABELED PROTEIN

Both disruption of the native protein structure and oxidation of iron in the haem/iron(II)-proto-porphyrin-IX residues were observed using t he Iodo-gen (1,3,4,6-tetrachloro-3 alpha,6 alpha-diphenylglycouril) me thod in I-125-labelling of haemoglobin. The reactions taking place aff ect the native structure of haemoglobin and result in a more acidic mo lecule. The detrimental effects were unaffected by the presence of iod ine. Electrophoretic studies demonstrate that I-125-labelling of haemo globin using the Bolton-Hunter reagent is the method of choice in orde r to preserve the native protein.