Comparative and optimized studies on radiosynthesis of O-（2-[^18F]fluoroethyl）-L-tyrosine

O-（2-[^18F]fluoroethyl）_L-tyrosine （[^18F]FET）, one of radiolabelled amino acids, is a very promising brain tumor positron emission tomography （PET） imaging agent and holds clinical potential. This paper described out a comparative and optimized radiosynthesis of [^18F]FET, concerning three aspects of its two-step preparation method, including reaction components, heating methods and reaction models. As a result, good radiochemical yield （about 45%, no-decay-corrected） and radiochemical purity （more than 95%） were achieved, and total synthesis time of [^18F]FET was shortened within 20 min and radiation exposure time also decreased.