Radical scavengers and the stability of 99mTc-radiopharmaceuticals.

It was found that compounds, such as ene-1,2-diols, diphenyl derivatives, and certain oxidants, are suited to prevent decomposition of 99mTc-radiopharmaceuticals. For effective stabilization of 99mTc(Sn)-DTPA different radioactive concentrations of 99mTcO-4 solution require different concentrations of stabilizers. As a possible reason for the decomposition of 99mTc-radiopharmaceuticals radicals are discussed. Superoxide anion or hydroperoxyl radicals are especially taken into consideration.