The biodistribution of radiocopper-labeled compounds.
Porphyrins form extremely stable chelates with Cu2+. Two copper radionuclides, 67Cu and 64Cu, have attractive nuclear decay properties for use in nuclear medicine applications. We have investigated the use of radiocopper-labeled porphyrins for localization in inflamed tissue and for attachment to antibodies for tumor imaging and therapy. We have examined the biodistribution of a 67Cu labeled porphyrin, [5, 10, 15, 20-tetrakis(4-carboxyphenyl) porphinato [67Cu] copper (II)], 67 CuTCPP. The 67CuTCPP was intravenously injected into the tail vein of Fischer F344 male rats. The kidneys, liver, and spleen localize the greatest amounts of 67CuTCPP. The elimination of 67CuTCPP from the body is described by a normal exponential decay curve with a biological half-life of 108 hours and an effective half-life of 32 hours. We have also examined the biodistribution of 5-(4-carboxyphenyl)-10, 15,20-tris(4-sulfophenyl) porphinato [67Cu] copper (II) anti-Thy 1.2 antibody conjugates in normal and tumor-bearing male AKR/J mice. The liver, kidney, and tumor have the highest uptake of the 67Cu labeled antibody conjugate. In all 67Cu labeled compounds studied, the blood clearance was rapid and the bone concentration of the radiolabeled species was low.
Mercer-Smith
J A
JA
Medical Radioisotopes Research Program, Los Alamos National Laboratory, NM 87545.
Cole
D A
DA
Roberts
J C
JC
Lewis
D
D
Behr
M J
MJ
Lavallee
D K
DK
D000818:Animals; D003300:Copper / Q000097:blood / Q000493:pharmacokinetics*; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D051379:Mice; D009928:Organ Specificity; D011166:Porphyrins / Q000097:blood / Q000493:pharmacokinetics*; D051381:Rats; D014407:Tumor Cells, Cultured
D011166:Porphyrins; D003300:Copper