Synthesis technology optimization on PET imaging agent ¹⁸F-FLT

3'-deoxy-3'-¹⁸F-fluorothymidine (¹⁸F-FLT) was synthesised with MTR-Nos-Boc-LT as precursor, uatemary ammonium salt as phase transfer catalyst, and buffer solution as neutralization solution. MicroPET imaging of A549 tumor in nude mice bearing tumor xenografts was performed by ¹⁸F-FLT. The results showed that uatemary ammonium salt is a good phase transfer catalyst, and can replace K_2.2.2/K₂CO₃ and elute ¹⁸F completely from QMA. The radiochemical purity was over 95% and the yield at EOS (end of synthesis) was 50% (uncorrected). (authors)