A new method for one-step, no-carrier-added synthesis of cholesteryl 4-[F-18]-fluorobenzoate ([F-18]-CFB), a radiotracer used in detection of adrenalmalignancies

Purpose: Cholesteryl 4-[F-18]-fluorobenzoate, a potential radiotracer used for adrenal and ovarian imaging, was prepared in no-carrier-added form from cholesteryl 4-N,N,N-trimethylanilinium trifluoromethanesulfonate. Methods. The reaction was performed in one step using Kryptofix2.2.2/[F-18], carbon ate as the counter ion and dimethyl sulfoxide as the solvent at 110 degrees C. Purification was performed using commercially available C-18 and Si Sep -Paks. Results, Column purification afforded the desired compound in 75-85 % radiochemical yield (EOS) with a specific activity about 74 KBq/mmole in about 20 minutes, with greater than 95% radiochemical and chemical purity ( HPLC and TLC analysis). Conclusions. This compound was prepared through a n ovel method which can be easily performed at distant locations from the mai n radionuclide production centers using Sep-Paks. The biodistribution of th is compound in mice was confirmed to be similar to that reported in the lit erature.