3’-脱氧-3’-[^18F]氟代胸腺苷自动化合成效率的影响因素

为提高^18F-FLT合成效率及其纯度，研究了以N—BOC为前体，利用国产多功能合成器自动化合成^18F-FLT时各种因素对合成效率及化学纯度和放化纯度的影响。结果显示，前体的化学量和合成体系中水的残留明显影响^18F-FLT的合成效率。增加N—BOC前体量，可明显提高合成效率；体系中残留水的存在明显降低合成效率；催化剂中碱的含量也会影响合成效率，最佳碱用量为前体与碱的摩尔比为1：1；半制备柱的平衡与否会影响产品的分离效率，从而影响产品的放化纯度，8％乙醇流动相则降低了产品的化学纯度。以上结果提示，使用国产多功能模块，通过优化合成参数，可明显提高^18F-FLT的合成效率，提高放化纯度和化学纯度。

Influence Factor on Automated Synthesis Yield of 3'-deoxy-3'-[18F] fluorothymidine

3'-deoxy-3'-[18F]-fluorothymidine (18F-FLT) was prepared from N-BOC precursor to improve the synthesis yield, chemical purity and radiochemical purity of 18F-FLT by home-made automated synthesis module. The results showed that residual water in synthesis system and the amount of precursor could affect the synthesis yield dramatically. The more the amount of precursor, the higher the synthesis yield between 10 mg to 30 mg of N-BOC. The residual water can decrease the synthesis yield. In the presence of excess base, the precursor was consumed by elimination before substitution was completed. When the precursor to base was optimal in 1 to 1, an overall 18F-FLT yield of 26.3% was achieved when the precursor amount was 20 mg（n=20）. The balance of semi-preparatiove HPLC Column can affect purified the final 18F-FLT product. The chemical purity of 18F-FLT could be decreased with 8% EtOH as mobile phase in semi-preparatiove HPLC. The high chemical purity, radiochemical purity and synthesis yield could be abtained by optimized the parameter of synthesis with home-made automated synthesis module.