Evaluation of a recoil-escape fiber target using 94Mo(p,n)94mTc to produce 94TcO4- precursor for radiolabeled compounds useful in positron emission tomography

A variety of compounds radiolabeled with ^99mTc(140 keV γ T₁2/=6 hours) are widely used in nuclear medicine imaging. These compounds can also be radiolabeled using the positron-emitting precursor ^94mTcO₄^- (T₁2/=53 minutes) and used with positron emission tomography (PET) to measure tissue concentrations in μCi/cm³, and produce kinetic data useful to understand the mechanism of drug action. This work-in-progress evaluates a novel accelerator target for producing ^94mTc. Positron emitters have been produced with fiber targets, using the principle of recoil escape in which the target atoms are in a solid form, while recovering the product radionuclide ion by stopping it in a liquid or a gas. The recoil ion is transported out of the target, leaving the remaining target material to be used repeatedly in subsequent production runs. Our proposed target is based on this method.