System and Method For Fractional Elution of Mother-Daughter Radionuclides

A method and a system for eluting a desired activity concentration of a daughter radionuclide-containing eluate obtained from a mixture of mother/daughter radionuclides is disclosed. The method comprises contacting separation particles with an aqueous solution containing a mixture of mother and daughter radionuclides wherein daughter radionuclides bind to separation particles and mother radionuclides does not. That contact is maintained for a time for unbound daughter radionuclide to bind to the separation particles. The unbound mother radionuclide is separated from the daughter radionuclide-bound separation particles using a washing solution. A first fractional amount of the bound daughter radionuclide is stripped from the separation particles using a volume of stripping solution so that an aqueous eluate solution having a desired daughter radionuclide activity is obtained. The remaining aqueous solution containing a second fractional amount of the desired daughter radionuclide still in the aqueous solution is retained.