System and Method For Fractional Elution of Mother-Daughter Radionuclides

An elution system, for eluting a desired activity concentration of a radionuclide activity of a desired daughter radionuclide-containing eluate, comprising:

• a first inlet for a conditioning fluid;
• a second inlet for a stripping fluid;
• a fluid movement system in fluid communication with the first inlet and the second inlet;
• a primary separation cartridge (PSC) bay in fluid communication with the fluid movement system;
• a source container in fluid communication with the fluid movement system;
• and
• a product bay in fluid communication with the fluid movement system.

In a method for enhancing the radionuclide activity of a desired daughter radionuclide-containing aqueous eluate separated from an aqueous composition containing a mother radionuclide and a daughter radionuclide in which said aqueous composition is 1) contacted with a separation medium in which said desired daughter radionuclide has a high affinity for and binds to said separation medium and said mother radionuclide has a low affinity for and does not bind to said separation medium to form a dispersion containing at least water, separation medium, desired daughter radionuclide, separation medium-bound to said desired daughter radionuclide, and unbound mother radionuclide 2) that contact is maintained for a time period sufficient for unbound desired daughter radionuclide to bind to the separation medium, 3) the unbound mother radionuclide is separated from the desired daughter radionuclide-bound separation medium formed in step 2) using a washing solution, and 4) the bound desired daughter radionuclide is stripped from the separation medium using a volume of stripping solution to form an aqueous eluate;

• wherein the improvement comprises stripping a first fractional amount of the bound desired daughter radionuclide from the separation particles using a volume of stripping solution to form the aqueous eluate solution having a desired daughter radionuclide activity, such that a second fractional amount of the desired daughter radionuclide is retained in the separation particles, thereby enhancing the desired daughter radionuclide activity in subsequent elutions than if a fractional amount of the desired daughter radionuclide was not retained in the separation particles.