Determination of the total retention capacity of <sup>99</sup>Mo in anionic extracting agent

The Nuclear Metrology Laboratory (LMN) at IPEN-CNEN/SP is developing a research project aimed at studying analytical techniques for determining radioactive impurities, emitting alpha and beta particles. This project started with the determination of impurities present in 99Mo, which is used to obtain the radiopharmaceutical 99mTc by means of radiochemical separation in the 99Mo/99mTc generator. The study of the anionic extracting agent Strata X-A widely used in quality analysis, was realized by means a breakthrough curve in order to validate its total exchange capacity for Mo. The breaking point was determined at (2.75 +/- 0.14) mL, showing that just one 0.5 g Strata X-A cartridge is sufficient to retain 1.0 mL of a (Na2MoO4+ 99Mo) solution in concentration of 2.42 g L- 1.