TF Antimony
Antiomony(Sb)
Tellurium(Te) to Antimony(Sb)
A pure Tellurium foils is immersed in a bremstraahlung beam to eject a proton from Te-120 leaving the Antimony isotope Se-119.
\gamma + Te-120 -> Sb-119 + p
Problem: Te-119 is only 0.1% of the natural abundance. Highest natural abundance is Te-126 at 19%, then Te-125 at 7%, Te-124 at 5%, Te-122 at 2.5%, Te-123 at 1%.
Sb-119 is an Auger electron emitter
Sb-117 is a PET analog => in 2 hrs Sb-117 decays emitting a positron that will annihilate and produce two 511 keV photons for a PET imager to detect.
Theranostic is an therapy with companion atoms. One atom serves as the radiological therapy and the other atom emits radiation that is detectable to a diagnostic device. For example Sb-119 emits low energy auger electrons to kill cancer cells while Sb-117 beta decays emitting a positron that annihilates and emits two 511 photons that are detectable by a PET scanner. The half life of Sb-117 is less than 3 hours and the half life of Sb-119 is 38 hours.
References
Accelerator based Production of Auger-Electron-emitting Isotopes for Radionuclide Therapy Helge ThisgaardR, PhD-theis, pg 22; Thesis may have led to this publication Thisgaard H.; Jensen M. Production of the Auger emitter 119Sb for targeted radionuclide therapy using a small PET-cyclotron. Appl. Radiat. Isot. 2009, 67, 34–38.
The Paradox of Using Radionuclides To Treat Disease, Thomas E. Albrecht-Schmitt, ACS Cent Sci. 2019 Mar 27; 5(3): 383–385