Magnesium-Molybate Compounds as Matrix for ⁹⁹Mo/^99mTc Generators

Abstract: This work reports the preparation of a ^99mTc generator based on conversion of ⁹⁹Mo produced by neutron irradiation, into insoluble magnesium ⁹⁹Mo-molybdates compounds as matrix. The effect of magnesium salt types and concentration, Mg:Mo molar ratios, pH of molybdate solutions, eluate volume as well as the addition order of molybdate and magnesium solutions’ influences on the final ^99mTc were evaluated. Polymetalates and polymolybdates salts either crystallized or amorphous were obtained depending on the magnesium salt and Mg:Mo molar ratio used in matrix preparation. ⁹⁹Mo/^99mTc generator production based on magnesium-⁹⁹Mo molybdate compounds allow reduction of preparation time and eliminates the use of specialized installations. The best generator performances were attained using matrices prepared from 0.1 mol/L MgCl₂·6H₂O solutions, ammonium molybdate solutions at pH 7 and at a Mg:Mo molar ratio of 1:1.