Automatic Synthesis of Ethyl [18F]Fluoroacetate and its First PET Imaging

[¹⁸F]FDG has been the most widely used as the PET tracer for detecting brain and systemic tumors, however, [¹⁸F]FDG uptake in adjacent normal brain tissue is so strong that [¹⁸F]FDG-PET imaging could not give an effect for brain functional imaging. In order to develop new PET radiopharmaceuticals to complement [¹⁸F]FDG, a simple method for automatic synthesis of ethyl [¹⁸F]fluoroacetate which can be operated in a commercial synthesizer has been established. The simple preparation of ethyl [¹⁸F]fluoroacetate was accomplished in a short synthesis time of 24 min and with a reproducible radiochemical yield of 41.4 plusmn 10.2 %, (decay corrected), and high radiochemical purity more than 98%. The PET imagings of ethyl [¹⁸F]fluoroacetate and sodium [¹⁸F]fluoroacetate were obtained in marmoset brain. SUV of ethyl [¹⁸F]fluoroacetate in the brain was 1.6, which was about 2.6 times higher than that of sodium [¹⁸F]fluoroacetate. The present results showed that ethyl [¹⁸F]fluoroacetate should be an ideal tracer for brain PET imaging.