The radionuclide 99 Mo has been prepared by 100 Mo(c, n) reaction using two types of natural molybdenum compound (molybdenum trioxide and zirconium molybdate gel) with the bremsstrahlung end-point energies of 10 and 15 MeV. After the equilibrium, 99m Tc was separated as NaTcO 4 from the irradiated samples using two different chemical procedures to examine the chemical yield. The separated Na[ 99m Tc]TcO 4 from the ZrMo gel has the 99Mo breakthrough of \10 -4 %, radiochemical purity[99 % as well as chemical impurities of Al, Mo and Zr \ 10 ppm. The estimation of 99 Mo and 99m Tc was done by using off-line c-ray spectrometric technique. The chemical yield of the separated 99m Tc from the dissolved molybdenum trioxide is 70.7-75.2 %, whereas in the undissolved zirconium molybdate gel, it is 19.1-43 %. The second method is preferable because it is user friendly in hospital radiopharmacy throughout the shelf-life.Keywords Medical isotope 99 Mo-9m Tc Á 100 Mo(c,n) reaction Á Molybdenum trioxide Á Zirconium molybdate gel Á Off-line c-ray spectrometric technique Á Chemical yield

Purpose of the Study:The indigenous design and technology development for processing large scale zirconium molybdate-Mo-99 (ZrMo-99) Geltech generator was successfully commissioned in Board of Radiation and Isotope Technology (BRIT), India, in 2006. The generator production facility comprises of four shielded plant facilities equipped with tongs and special process gadgets amenable for remote operations for radiochemical processing of ZrMo-99 gel.Results:Over 2800 Geltech generators have been processed and supplied to user hospitals during the period 2006-2013. Geltech generator supplied by BRIT was initially not sterile. Simple elution of Tc-99m is performed by a sterile evacuated vial with sterile and pyrogen free 0.9% NaCl solution to obtain sodium (Tc-99m) pertechnetate solution. A special type online 0.22 μm membrane filter has been identified and adapted in Geltech generator.Conclusions:The online filtration of Tc-99m from Geltech generator; thus, provided sterile Tc-99m sodium pertechnetate solution. Generators assembled with modified filter assembly were supplied to local hospital in Mumbai Radiation Medicine Centre (RMC) and S.G.S. Medical College and KEM Hospital) and excellent performances were reported by users.