A high efficiency and rapidly automatic method of synthesizing 11C-Dopamine by using GE synthesizer-TRACERlab FXc

Objectives Dopamine is an important neurotransmitter, which has the close relationship with neurological and cardiologic diseases. PET imaging of ¹¹C-Dopamine is of great meaning for congestive heart failure, myocardial ischemia, abnormal heart rate and other myocardial disease. Achieving automatic synthesis of ¹¹C-Dopamine using GE synthesis module-TRACElab FXc.

Methods we use the gas cycling method to convert ¹¹C-CH₄ to ¹¹C-CH₃I, dopamine chloride was then added to react with ¹¹C-CH₃I, the product was separated by HPLC and ¹¹C-Dopamine was completed. 3mCi ¹¹C-Dopamine was injected into one rabbit and then scan the rabbit with PET/CT 20min after the injection. The distribution percentage of brain, lung, liver, kidneys and bladder were calculated.

Results we accomplished automatic synthesis of ¹¹C-Dopamine by using TRACERlab FXc, the total synthesis time are 50 minute, and mean uncorrected yield is 16%; 11C-Dopamine was dissolved in 1% acetate acid/water. Our data show that 5mg precursor is suitable and best sodium hydroxyl quantity is 0.3ml 0.3mol/l, which is used to dissolve precursor. Uncorrected yield of ¹¹C-Dopamine is about 16% and radiochemical purity is 100%. According the PET/CT imaging, distribution percentages of ¹¹C-Dopamine in brain, lung, liver, kidneys and bladder are 0.34%, 1.63%, 0.5%, 4.19%, 10.09% and 83.26% respectively.

Conclusions we achieved automatic and simple synthesis of ¹¹C-Dopamine by using cheap precursor-dopamine chloride, the yield of 11C-Dopamine can fulfill clinical use, and PET/CT rabbit image show clear uptake in heart.