99Mo/99mTc radioisotope generator based on adsorption of 99Mo (VI) on cerium (IV) molybdate column matrix

Based on neutron activated Mo-99 a procedure for preparation of Mo- 99/Tc-99m radioisotope generator was developed. Batch equilibration method was used to investigate the sorption behavior of Mo (VI) (10(-4) M) in chloride and nitrate solutions on cerium (IV) molybdate gel matrix using Mo-99 radiotracer. The breakthrough sorption capacity of cerium molybdate gel matrix for Mo-99 (VI) (3 x 10(-2) M) were found to be 0.54 mmol/g of the sorbent [1 g column (0.6 cm i.d.)]. Elution performance of the generated 99 mTc from cerium molybdate-Mo-99 chromatographic column was investigated as a function of inside diameter of the column, amount of the bed matrix and flow rate of the eluent. Based on the obtained results, Mo- 99/Tc-99m radioisotope generator was prepared based on adsorption of neutron activated Mo-99 (VI) of low specific activity onto chromatographic columns packed with 5 g cerium molybdate gel matrix. The radioactivity of Tc-99m is periodically eluted with 10 mL 0.9 % NaCl solution at a flow rate of 1 mL/min. Elution yield of 78 +/- 5 % was obtained with high chemical, radionuclidic (Mo-99 breakthrough 1 x 10(-3) +/- 0.3 x 10(-3) %) and radiochemical purity (97 +/- 2 %).