Lee J, Garmestani K, Wu C, Brechbiel M W, Chang H K, Choi C W, Gansow O A, Carrasquillo J A, Paik C H
Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-1180, USA.
Nucl Med Biol. 1997 Apr;24(3):225-30. doi: 10.1016/s0969-8051(97)00056-5.
2-(p-isothiocyanatobenzyl)-1,4,7-triazacyclononane-1,4,7-triacetic acid (C-NOTA) or 2-(p-isothiocyanatobenzyl)-6-methyl-diethylenetriamine pentaacetic acid (1B4M) was conjugated to monoclonal antibody T101 (IgG2a), radiolabeled with 111In or 67Ga and then purified through size-exclusion HPLC. 111In 1B4M-T101 and 67Ga C-NOTA-T101 were stable in in vitro serum at 37 degrees C. In contrast, 111In C-NOTA-T101 and 67Ga 1B4M-T101 were unstable. The biodistribution in normal mice reflected the instability of the metal complex; the less-stable 111In C-NOTA conjugate left less tracer in blood, but more in liver and kidney whereas the less-stable 67Ga 1B4M conjugate left less tracer in blood, but more in bone. The biodistribution data suggest that the difference shown between the 111In and 67Ga conjugates might be mediated by differences in the in vivo chemistry of the metallic ions.
将2-(对异硫氰酸苄基)-1,4,7-三氮杂环壬烷-1,4,7-三乙酸（C-NOTA）或2-(对异硫氰酸苄基)-6-甲基二乙烯三胺五乙酸（1B4M）与单克隆抗体T101（IgG2a）偶联，用111铟或67镓进行放射性标记，然后通过尺寸排阻高效液相色谱法进行纯化。111铟标记的1B4M-T101和67镓标记的C-NOTA-T101在37℃的体外血清中稳定。相比之下，111铟标记的C-NOTA-T101和67镓标记的1B4M-T101不稳定。正常小鼠体内的生物分布反映了金属络合物的不稳定性；稳定性较差的111铟C-NOTA偶联物在血液中留下的示踪剂较少，但在肝脏和肾脏中较多，而稳定性较差的67镓1B4M偶联物在血液中留下的示踪剂较少，但在骨骼中较多。生物分布数据表明，111铟和67镓偶联物之间显示的差异可能是由金属离子体内化学性质的差异介导的。
