Determination of 99Tc activity in sodium 99mTc-pertechnetate injections produced by the 99Mo-99mTc extraction generator

A spectrometric method was developed allowing to evaluate the beta component of beta-gamma source spectra and to determine the percentage activity of pure beta sources contained in the radiopharmaceutical. The application is described of the method in determining 99Tc in injections of sodium 99mTc-pertechnetate produced using a 99Mo-99mTc extraction generator. The experiments were carried out with a spectrometer provided with a CaF2(Eu) 25 mm dia.x5 mm scintillator and with a Canberra Series 85 multi-channel analyzer. The results of the experiments are compared with calculated results and are found to be in good agreement. (Z.M.). 7 figs., 6 tabs., 7 refs