Analysis of [15O]CO2
This reaction is reversible, but since there is much more water in the body than carbon dioxide, practically all 15O is labelling water. The reaction rate of carbonic anhydrase is only limited by the diffusion rate of the substrates, and equilibrium is thus instant as compared to the time-resolution of PET.
Notice that 11C and 15O labelled CO2 are completely different tracers.
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Updated at: 2017-09-07
Created at: 2009-04-24
Written by: Vesa Oikonen