Highly efficient production of [18F]fallypride using small amounts of base concentration

To minimize the base concentration of a phase-transfer catalyst, [F-18]fluoride was extracted from O-18-enriched water trapped on an activated ion exchange cartridge (Chromafix (R) PS-HCO3) using different concentrations of tetrabutylammonium bicarbonate (TBAHCO(3)) or Kryptofix 2.2 2./K2CO3 in organic solvents such as CH3CN/H2O or MeOH/H2O. The optimal labeling condition for [F-18]fallypride with automated synthesis was that 2 mg of tosyl-fallypride in acetonitrile (1 mL) was heated at 100 degrees C for 10 min using 40% TBAHCO(3) (10 mu L). [F-18]Fallypride was obtained with a high radiochemical yield of approximately 68 +/- 1 6% (decay-corrected, n=42) with a total synthesis time of 51 +/- 1.2 min, including HPLC purification and solid-phase purification for the final formulation. (c) 2010 Elsevier Ltd. All rights reserved.