^(125)I-RC-160的标记方法研究及其正常小鼠体内的分布特征  

Study on labelling methods of^(125)I-RC-160 and its biodistribution in animals

作　　者：汪静[1] 王喜青[2] 王连刚[2] 李富军[1] 邓敬兰[1] 

机构地区：[1]第四军医大学西京医院核医学科,西安710032 [2]第四军医大学西京医院实验外科,西安710032

出　　处：《核技术》2002年第11期897-900,共4页Nuclear Techniques

基　　金：国家自然科学基金资助项目 (395 0 0 0 35 ;39870 2 18);全军医药卫生科研基金资助课题 (0 1MB12 0 )

摘　　要：研究了一种高效碘标多肽RC - 16 0的方法 ,在其中以溴代琥珀酰亚胺 (NBS)为氧化剂 ,常规氯胺T法作为对照。对12 5I -RC - 16 0的标记率、比活度进行了评价 ,并观察12 5I -RC - 16 0在正常小鼠体内的生物分布特征。结果显示 :在丙酮:生理盐水 =1:1体系中 ,测得12 5I -RC - 16 0的标记率NBS法为 92 %,比活度为 1.95× 10 12 Bq/mmoL ,标记率随NBS用量增加而增高 ,最佳用量比为RC - 16 0 (μg):12 5I(MBq):NBS(μg) =3:7.4:1,且产物无需纯化 ;Ch -T法标记率为5 6 %,比活度为 0 .6 5× 10 12 Bq/mmoL ,经SepPaK -C18反向色谱柱纯化 ,12 5I -RC - 16 0的标记率可达 92 %。标记物在血中清除较快 ,注射后不到 1h血中的放射性就下降了 87.2 %;12 5I -RC -16 0在甲状腺及肾的浓集度很低 ,主要经过消化系统排出体外。A method for the iodination of peptide RC-160 with high efficiency was developed. RC-160 was iodinated with N-bromosuccinimide (NBS) as oxidant, the conventional chloramine T (Ch-T) method was used as control. The labelling condition of NBS method was optimized and radiolabelled conjugate 125I-RC-160 was assessed as follows: no further purification was needed, the measured labelling yield of 125I-RC-160 was 92% and the specific activity was 1.95×10 12Bq/mmoL. The yield increased as the amount of NBS increased. The optimal ratio of RC-160(μg): 125I(MBq):NBS(μg)was 3:7.4:1. For Ch-T method, the labelling yield is 56% and specific activity was 0.65×10 12Bq/mmoL, but after purification by SepPaK-C 18, the labelling yield may reach as high as 92%. 1h after injection, radioactivity in blood decreased by 87.2%. No obvious concentration of 125I-RC-160 in thyroid or kidney was observed.

关 键 词：分布特征 生长抑素类似物 放射性同位素 同位素标记 碘125 代谢 RC-160 

分 类 号：R817[医药卫生—影像医学与核医学]