Labelling of bleomycin with cobalt-57, indium-111, technetium-99m, mercury-197, lead-203, and copper-67.
The radiochemical purity of the cobalt-57 complex of bleomycin could be enhanced by adjusting the pH of the final product to a value between 5 and 6. This radiopharmaceutical appeared to have better tumor visualizing properties compared to the not neutralized preparation. The clinical use of the cobalt-57 bleomycin complex is however limited by the long physical half-life of the label, causing a risk of radioactive contamination. It appeared to be possible to label bleomycin with radioactive cations (111In3+, 99mTc4+, 197Hg2+ and 67Cu2+) having suitable gamma ray energies and short half-lifes. These bleomycin complexes showed a high radio-chemical purity judged by their behaviour on thin layer chromatography, paper chromatography, and electrophoresis, but their application as tumor visualizing radiopharmaceutical turned out to be disappointing compared with cobalt-57 bleomycin.
D001761:Bleomycin; D003037:Cobalt Radioisotopes; D003300:Copper; D004355:Drug Stability; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007204:Indium; D007553:Isotope Labeling / Q000592:standards; D007854:Lead; D008631:Mercury Radioisotopes; D009369:Neoplasms / Q000175:diagnosis; D011868:Radioisotopes; D011877:Radionuclide Imaging; D013667:Technetium
D003037:Cobalt Radioisotopes; D008631:Mercury Radioisotopes; D011868:Radioisotopes; D007204:Indium; D001761:Bleomycin; D007854:Lead; D013667:Technetium; D003300:Copper