Eckelman W C, Kubota H, Siegel B A, Komai T, Rzeszotarski W J, Reba R C
J Nucl Med. 1976 May;17(5):385-8.
Cobalt-57-bleomycin is a clinically useful tumor-localizing agent, but attempts to label bleomycin (BLEO) with other radionuclides have been made because of the long physical half-life of 57Co. As an alternative labeling approach, we iodinated BLEO both directly on the imidazole ring and indirectly by reaction with N-succinimidyl 3-(4-hydroxy, 3-iodophenyl) propionate. Directly iodinated BLEO retained antibacterial activity, but in tumor-bearing rats it showed a lower tumor-to-blood ratio (2.3) at 2 hr than did 57Co-BLEO (11.8). The antibacterial activity of the indirectly labeled BLEO was markedly reduced and this material showed a tumor-to-blood ratio of 0.55 at 2 hr. The radioiodinated bleomycins are not suitable substitutes for 57Co-BLEO as tumor-imaging radiopharmaceuticals.
钴-57-博来霉素是一种临床有用的肿瘤定位剂，但由于钴-57的物理半衰期长，人们已尝试用其他放射性核素标记博来霉素（BLEO）。作为一种替代标记方法，我们既直接在咪唑环上对博来霉素进行碘化，也通过与N-琥珀酰亚胺基3-（4-羟基，3-碘苯基）丙酸反应进行间接碘化。直接碘化的博来霉素保留了抗菌活性，但在荷瘤大鼠中，其在2小时时的肿瘤与血液比值（2.3）低于钴-57-博来霉素（11.8）。间接标记的博来霉素的抗菌活性显著降低，该物质在2小时时的肿瘤与血液比值为0.
