Optimization of the radiosynthesis of the Alzheimer tracer 2-(4-N-[11C]methylaminophenyl)-6-hydroxybenzothiazole ([11C]PIB)

[C-11]PIB is still the standard PET compound for Alzheimer imaging targeting beta-amyloid plaques. We aimed to establish a fully-automated procedure for the synthesis and purification of [C-11]PIB with a high degree of reliability and improved specific activity as well as a suitable and fast quality control assay. The optimum reaction conditions were 75 degrees C, 4 mg/mL precursor yielding at 48.0 +/- 2.7% (EOS, based on [C-11]CH3OTf, corrected for decay), 183 +/- 14 GBq/mu mol specific activity and >99% radiochemical purity. Time consumption was kept to a minimum (40 min from EOB) and overall yields were enough to serve 2 consecutive patients with a single preparation. (C) 2011 Elsevier Ltd. All rights reserved.