Gómez-Vallejo Vanessa, Llop Jordi
Institut Alta Tecnologia PRBB-Fundació Privada, Parc de Recerca Biomèdica de Barcelona, C/Dr. Aiguader, 88 08003 Barcelona, Spain.
Appl Radiat Isot. 2009 Jan;67(1):111-4. doi: 10.1016/j.apradiso.2008.09.012. Epub 2008 Oct 5.
Positron emission tomography (PET) is a powerful molecular imaging technique based on the administration and detection of radioactive (positron emitting) species. In some applications, the concept of specific activity becomes especially important in order to prevent undesired pharmacological and/or toxic effects after injection of the radiotracer. Problems to obtain high specific activities are found when (11)C-labeled compounds are prepared by methylation following the so called "wet" method, which consists of a simple route but usually yields radiotracers highly diluted with the stable specie. In the present work, the main sources of contamination by stable carbon in the [(11)C]CH(3)I synthesis following the "wet" method have been analyzed and their individual contribution has been quantified. The results show that the most relevant contamination of CO(2) is generated during the bombardment process.
正电子发射断层扫描（PET）是一种强大的分子成像技术，基于放射性（发射正电子）物质的给药和检测。在某些应用中，比活度的概念变得尤为重要，以防止注射放射性示踪剂后出现不良的药理和/或毒性作用。当通过所谓的“湿”法甲基化制备（11）C标记的化合物时，会发现获得高比活度存在问题，该方法路线简单，但通常产生的放射性示踪剂被稳定物质高度稀释。在本工作中，分析了“湿”法合成[（11）C]CH（3）I过程中稳定碳污染的主要来源，并对其各自的贡献进行了量化。结果表明，最主要的CO（2）污染是在轰击过程中产生的。
