Optimization of [11C]DASB-synthesis: Vessel-based and flow-through microreactor methods

The intention for the present study was to implement a microfluidic set-up for N-11C-methylations in a flow-through microreactor device with [11C]DASB as model-compound and [11C]CH3I and [11C]CH3OTf, respectively, as 11C-methylation agents. Due to an observed “aging” effect of the 11C-methylation agents' solution, this goal was not achieved. Nevertheless, based on these observations, the time consumption for the vessel-based routine production of [11C]DASB was reduced (34±1 min) and RCY was increased to 45.1±4.6% (EOB; 5.2±0.95 GBq EOS).

► Aging effect of 11C-methylation agents observed.
► Microfluidic set-up for remote 11C-methylations questionable.
► Vessel-based approach was ameliorated.
► Radiochem. yield of [11C]DASB was increased to 45.1±4.6% (EOB; 5.2±0.95 GBq EOS).