Automated synthesis and PET evaluation of both enantiomers of [18F]FMISO

Although the (R)-enantiomer of [18F]FMISO demonstrated a somewhat faster initial tumor and muscle uptake no significant enantioselective tissue uptake was observed at later time points. The T/M- and T/L- ratios for the (R)- and (S)-forms were the same within the experimental error at all times. Therefore, the use of enantiopure [18F]FMISO is unlikely to present any practical clinical benefit for PET imaging.