FAU的碘化标记及其在小鼠体内的生物学分布

Radiolabeling FAU with ^(125)I and its biodistribution in mice

目的研究^(125)I-氟-碘阿糖呋喃基尿嘧啶(FIAU)的性质及在小鼠体内的生物学分布。方法利用 Iodogen 碘化标记法对氟脱氧呋喃糖尿嘧啶(FAU)进行标记,用 Sep-Pak C18反相色谱柱进行纯化;观察^(125)I-FIAU 的标记率、放化纯、体外稳定性及其在小鼠体内的生物学分布。结果以Iodogen 固相氧化法标记 FAU,得到^(125)I-FIAU,标记率为(63.12±5.01)%;产物经 Sep-Pak C18反相色谱柱纯化后放化纯为(98.60±0.52)%;^(125)I-FIAU 在 PBS 及人血清中37℃条件下稳定,24 h 后放化纯>95.04%。生物学分布实验表明:标记物从小鼠血液中清除迅速,用每克组织百分注射剂量率(%ID/g)表示,0.5 h 为(4.33±1.00)%ID/g,2 h 下降为(0.77±0.06)%ID/g,至24 h 时基本清除完毕;肾脏是其主要排泄器官。结论 Iodogen 固相氧化法可以进行 FAU 碘化标记,得到标记率、放化纯及稳定性较好的^(125)I-FIAU,该标记物主要经肾脏排泄。

Objecuve The aim of this study was to label 2＇-fluoro-2＇-deoxy-1-β-D-arabinofurano- syluracil （FAU） with ^125 I, and to investigate the characteristics of the labeled compound as well as its biodistribution in mice. Methods FAU was radiolabeled with Na^125 I using the Iodogen method. The Sep-Pak C18 reverse phase column was used to purify the labeled product. The labeling efficiency, radiochemical purity, the in vitro stability and its biodistribution in mice were observed. Results FAU was successfully labeled with Na^125 I with the labeling efficiency of （63.12 ±5. 01 ） %. The radiochemical purity was （ 98.60 ± 0.52）%. ^125 I-iodo-FAU （FIAU） was stable in PBS and fresh human serum under 37℃ and the radiochemical purity remained more than 95.04% after 24 h. Mouse experiment showed that the radiolabeled product was washed out from blood quickly. The uptake expressed as percentage activity of injected dose per gram of tissue （ % ID/g） was （4.33 ± 1.00） % ID/g at 0.5 h and （0.71 ±0.06） % ID/g at 2 h after injection. The ^125 I-FIAU was mainly excreted through kidney. Conclusions ^125 I-FIAU could be obtained by labeling FAU with the Iodogen method with satisfactory labeling efficiency, radiochemical purity and stability. Mouse biodistribution experiment showed it was mainly excreted through kidney.