Technetium-99m is mostly eluted from 99Mo/99mTc generator system in all nuclear medicine departments where radiopharmaceuticals are prepared for gamma imaging purposes. The clinically useful lifetime of a fission based 99Mo/99mTc generator is ~2 weeks. At the end of first working week, the radioactive concentration of the eluate is about a quarter of that at the beginning of the week that places limitations on the clinical procedures. These include 99mTc-sestamibi for myocardial perfusion studies and 99mTc-ECD forbrain imaging. Hence safe procedure is needed for the concentration of pertechnetate obtained from column chromatography generators. The concentrated solution of pertechnetate obtained by these methods were successfully employed for labeling of MIBI and ECD kits.