Development of the on-column labelling method for automated preparation of radiopharmaceuticals for PET study

[&lt；@D111@&gt；D1C]氨基酸和[&lt；@D111@&gt；D1C]氨基酸的自动制备发展了一种使用硅藻土的新的、方便的柱上方法。[&lt；@D111@&gt；D1C]二氧化碳与格氏试剂在液层中反应，并通过液-液萃取提纯，在商用硅藻土Extrelut&lt；@d1()SY.enCircledR.[&lt；@D111@&gt；D1C]二氧化碳被有效地捕获到由Extrelut色谱柱保存的试剂溶液和通过dil淬火形成的游离[&lt；@D111@&gt；D1C]脂肪酸中。通过将适当的有机溶剂从反应柱流动到溶剂中，然后从溶剂中进入用于[&lt；@D111@&gt；D1C]冰醋酸的Extrelut短柱或用于[&lt；@D111@&gt；D1C]棕榈酸的硅胶，顺序地提取HCl。以90%以上的放化产率合成了[&lt；@D11@&gt；D1C]冰醋酸，[&lt；@D111@&gt；D1C]棕榈酸的合成约为用相同的反应体系和步骤，在15分钟内得到50%的放化产率。整个合成过程，包括捕获和反应以及随后的萃取和酸解，都得到了显著的简化，并成功地适应了[11&gt；C]ACPC的常规生产。所建立的方法在轰击结束后的40分钟内提供了放射化学纯度的[11；C]ACPC，放化产率在60%以上。因此，本研究证明，基于柱萃取法的柱上标记可以简化制备PET放射性药物的合成步骤，并便于PET常规使用的自动化。

A new, convenient on-column method using kieselguhr has been developed for the automated preparations of [<@D111@>D1C] fatty acids and [<@D111@>D1C] amino acids The reaction of [<@D111@>D1C] carbon dioxide with a Grignard reagent and purification by liquid-liquid extraction were carried out in a liquid layr supported by a commercially available kieselauhr, Extrelut<@D1(]SY.encircledR.[)@>D1 (Merck). [<@D111@>D1C] Carbon dioxide was efficiently trapped into a reagent solution kept by an Extrelut column and the free [<@D111@>D1C] fatty acid formed by quenching with dil. HCl was sequentially extracted by flowing an appropriate organic solvent from the reaction column into the solvent and then from the solvent into a short column of Extrelut for [<@D111@>D1C] acetic acid or silica gel for [<@D111@>D1C] palmitic acid. [<@D11@>D1C] Acetic acid was prepared in over 90% radiochemical yield and [<@D111@>D1C] palmitic acid in approx. 50% radiochemical yield, within 15 min, with the same system and procedure.The on-column synthesis of 1-aminocyclopentane-1-[^<11>C] carboxylic acid ( [^<11>C] ACPC) from [^<11>C] HCN was also carried out. The whole synthetic procedure, including the trapping and reaction of [^<11>C] HCN as well as the following extraction and acid hydrolysis, was remarkably simplified, and the preparation has been successfully accommodated to routine production of [^<11>C] ACPC.The established method provides radiochemically pure [^<11>C] ACPC in over 60% radiochemical yield within 40 min after the end of bombardment.Thus, the present study has demonstrated that the on-column labelling based on column extraction can simplify synthetic procedures for the preparation of PET radiopoharmaceuticals and facilitate automation for routine use in PET.