采用Iodogen法对Annexin V进行了125I标记,并观察了其在正常小鼠体内的分布情况。标记结果显示,125I-Annexin V标记率达94.9%,纯化后放化纯度达99%;室温放置72 h后,放化纯度仍保持在92%以上,表明其体外稳定性较好。生物分布结果显示,125I-Annexin V在肾脏中放射活性最高,其次为血液、肝脏、心、肺、脾;脑不吸收125I-Annexin V;肌肉、骨骼组织摄取亦较少;各组织、器官放射性摄取在1 h内除血液下降稍慢外,其余均有明显下降。表明125I-Annexin V适合用作核医学诊断试剂。 Annexin V was labeled with 125I by Iodogen method and its distribution in normal mice was observed. The results of labeling showed that the labeling efficiency of 125I-Annexin V reached 94.9%, and the radiochemical purity reached 99% after purification. After 72 hours at room temperature, the radiochemical purity remained above 92%, indicating that its stability in vitro was good. The biodistribution results showed that 125I-Annexin V had the highest radioactivity in the kidney, followed by the blood, liver, heart, lung and spleen; 125I-Annexin V was not absorbed by the brain; the muscle and skeletal tissues were also less ingested; Ingestion within 1 h in addition to the slower decline in blood, the rest were significantly decreased. 125I-Annexin V is suitable for use as a nuclear medicine diagnostic reagent.