(N-[^(18)F]氟甲基)胆碱的半自动合成和无菌型炎症PET显像评价

Semi-automatic Synthesis and PET Imaging Evaluation of ^(18)F-fluoromethylcholine With the Aseptic Inflammation Model

通过对现有的合成模块进行改进,实现了(N-[18F]氟甲基)胆碱(18F-FCH)的半自动合成,并用其进行了无菌型炎症PET显像。以CH2Br2为前体,经过氟化反应制备甲基化试剂18FCH2Br,在柱与N,N-二甲基乙醇胺进行反应,并经过Sep Pak tC18和Sep Pak CM小柱联用纯化的方法,得到放化纯度大于95%的18F-FCH注射液,放化产率为12%±2%(n=3,按18F-计算,未校正),放化合成时间为35min。PET显像表明,肌肉注射0.2mL松节油,4天后形成的炎症模型具有18F-FDG最高摄取,而18F-FCH在炎症处具有轻度的放射性浓聚,因此在18F-FCH肿瘤显像时应考虑炎症的可能性。

Semi-automated synthesis of ^18F-fluoromethylcholine （18 F-FCH） was achieved with the modification of the commercial synthesis model and the PET imaging of aseptic inflammation model was performed with^18F-FCH. ^18FCH2Br as a [^188 F] fluoromethylation agent was prepared by the fluorination of dibromomethane followed by distillation from the reaction vessel. The obtained IS FCHzBr then reacted with N, N-dimethylamino ethanol loaded on the Sep Pak tC18 cartridge to give ^18F-FCH. After being purified on the solidphase extraction cartridges, ^18F-FCH was obtained with 12 %± 2 % radiochemieal yields （n =3, decay not corrected）, and higher than 95% radiochemical purity. The synthesis time was less than 35 min. PET imaging showed that ^18F-FCH had a slightly lower uptake than ^18F-FDG in the inflammation tissues infected with turpentine oil, suggesting a potential use of ^18F-FCt-I to differentiate between a tumor and inflammation by PET imaging.