Choline C-11

Carbon-11-choline (choline C-11 or ¹¹C-choline) is the most studied isotope carbon-11 PET radiopharmaceutical.  The molecule is used for oncologic Imaging ^1-4. Choline is one of the components of phosphatidylcholine, a fundamental element of cell membrane phospholipids ⁵. Cancer cells tend to have a high uptake of the radio-tracer; the increased uptake is presumed to be due to the increase in membrane phosphatidylcholine synthesis (up-regulation of the choline kinase enzyme) ⁶.

Physical characteristics of carbon-11

• Half-life: 20.38 minutes ⁷
• E_max (ß⁺): 961 KeV
• ß⁺ decay: 100%

Quality controls

If the ¹¹C-choline is employed for brain imaging it is important that there is no 2-dimethylaminoethanol (the precursor used for synthesis) in the injectable solution. 2-dimethylaminoethanol (deanol), in fact, presents to consider with respect to choline a greater affinity for the transport molecules present on the blood-brain barrier ⁸.