Jørgensen K H, Larsen U D
Diabetologia. 1980;19(6):546-54. doi: 10.1007/BF00253183.
Mono-(125)I-(Tyr A19)-insulin (MonoA19) was prepared by iodinating MC porcine insulin with (125)I in acid medium using iodate (as oxidizing agent), followed by anion-exchange chromatography. Mono-(125)I-(Tyr A14)-insulin (MonoA14) was prepared by iodinating MC porcine insulin with (125)I, using H(2)O(2)/lactoperoxidase at neutral pH, followed by anion-exchange chromatography. The specific radioactivities were in the ranges of 120-200 and 220-300 mCi/mg for MonoA19 and MonoA14, respectively. Analyses of the intramolecular distributions of (125)I demonstrated that the preparations were 97-98% radiochemically pure. In both preparations, 98-99% of the radioactivity was capable of binding to insulin antibodies for up to 6 months of storage of the tracers. The IRI concentration decreased with the duration of storage. The greatest observed fall in IRI concentration was 70%. The ime course could be explained by the assumption that the disintegration of a (125)I-nucleus destroys the immunoreactivity of the insulin molecule in which the decay occurs.
单 -（125）I -（酪氨酸A19）-胰岛素（MonoA19）是通过在酸性介质中使用碘酸盐（作为氧化剂）用（125）I对MC猪胰岛素进行碘化，随后进行阴离子交换色谱法制备的。单 -（125）I -（酪氨酸A14）-胰岛素（MonoA14）是在中性pH下使用H₂O₂/乳过氧化物酶用（125）I对MC猪胰岛素进行碘化，随后进行阴离子交换色谱法制备的。MonoA19和MonoA14的比放射性分别在120 - 200和220 - 300 mCi/mg范围内。对（125）I的分子内分布分析表明，这些制剂的放射化学纯度为97 - 98%。在这两种制剂中，98 - 99%的放射性在示踪剂储存长达6个月的时间内能够与胰岛素抗体结合。IRI浓度随储存时间而降低。观察到的IRI浓度最大下降为70%。这种时间进程可以通过以下假设来解释，即（125）I核的衰变会破坏发生衰变的胰岛素分子的免疫反应性。
