自动化合成18F-FDDNP及其生物学分布

目的研究高效、简单的自动化合成脑内老年斑沉积显像剂2-(1-{6-[2-18F-乙基](甲基)氨}-2-萘-乙叉)丙二腈(18F-FDDNP)的方法及其小鼠生物学分布.方法采用化学过程控制单元(CPCU)控制整个过程,18F-在乙腈溶液中与前体2-(1-{6-[2-p-甲苯磺酰氧乙基](甲基)氨}-2-萘-乙叉)丙二腈直接反应生成18F-FDDNP,混合物装柱,产品被C-18柱吸附,用水冲洗柱,用少量乙醇淋出,加水稀释.NH小鼠给药后不同时间处死,分别取不同器官称重并测放射性计数.结果18F-FDDNP放化产率为35.7%(不校正),合成时间为20min,无需HPLC分离,放化纯＞95%.注射18F-FDDNP后,放射性主要分布在肝内,脑摄取较高,但清除较慢.结论自动化合成18F-FDDNP速度快,效率高.

Automated synthesis of 18F-FDDNP and its biodistribution in mice

Objective To study a method for automated synthesis of 2-(1-{6-[2- 18F-fluoroethyl](methyl)amino}-2-naphthy-ethylidene)malononitrile ( 18F-FDDNP) for senile plaque imaging, and to research the biodistribution of 18F-FDDNP in mice. Methods 18F ion was reacted with precursor 2-(1-{6-[2-tso-ethyl](methyl)amino}-2-naphthy-ethylidene)malononitrile (DMTEAN) in a chemical process control unit (CPCU). The crude product was transported to a column. 18F-FDDNP was absorbed on the column, the column was washed by water. 18F-FDDNP was then eluted from the column with small volume of ethanol. The mice were sacrificed, brain and tissue samples from other organs were weighed and radiocounted. Results It took 20 min for synthesizing 18F-FDDNP at CPCU, the radiochemical yield was 35.7% (end of synthesis), the radiochemistry purity was over 95%. Radioactivity was mainly distributed in liver and brain. The greater accumulation and slower clearance was observed in brain. Conclusion 18F-FDDNP can be synthesized at CPCU with high synthesis yield for about 20 min.