Determination of the specific activity of fission-based 99Mo using differential pulse polarography

Abstract

The specific activity of fission-based 99Mo is significantly lower than the theoretical “carrier-free” value because of the contribution from a number of stable molybdenum isotopes which are formed concurrently during irradiation of the uranium target. A rapid analytical technique employing differential pulse polarography was devised to measure the concentrations of molybdenum, and hence the specific activity of 99Mo, in small volumes of radioactive sample. Submicrogram quantities of the analyte can be measured by using the catalytic reduction wave of molybdenum in a nitric acid-ammonium nitrate based supporting electrolyte. Measured specific activities range from 3.1 × 10 4 to 5.4 × 10 4 Cig −1; these values were in close agreement with the theoretically computed values.