Problem
Lu-177 is a radioactive isotope in high demand as a therapeutic for treatment of several types of cancer and may have other nuclear medicine applications. Current estimates are that the demand for Lu-177 will exceed 190,000 doses per year by 2023. No carrier added Lu-177 is produced by irradiation of enriched Yb in a nuclear reactor followed by a difficult chemical separation of the Lu-177 from the remaining Yb. The enriched Yb is then recycled back into the reactor for further production. Current methods for production require large Yb targets, costly chemical resins, potentially significant losses of both the Lu-177 (due to decay in the columns) and the unirradiated Yb, and can produce large volumes of radioactive waste. Most of these drawbacks are due to the extremely dilute (1-10 ppm) quantity of Lu-177 in the irradiated target solution. A method is needed for removing the irradiated materials directly from the target solution such that it can be concentrated into a solution without other lanthanides.
Solution
An Yb or Re target solution is combined with a solid suspension of nanomaterials to capture the activated products produced during irradiation such that they can be easily filtered from the non-activated, liquid target material with a dramatic increase in Lu-177 or Re-186 concentration and nearly complete recovery of the unirradiated Yb target solution.
Features
The invention uses a unique suspension of nanomaterials that can be saturated with the liquid target material, dried to a powdered form in which the target and capture material are intimately mixed, and capture the hot atoms produced during irradiation on the capture material. The irradiated sample can then be re-dissolved into an aqueous solution and the liquid target material can be physically separated from the solid capture material. While developed for usage in production of Lu-177 from Yb solutions and Re-186 from Re solutions, this invention can also be applied to the production of several other medical isotopes, including Tb-161 and Mo-99.
Benefits
This invention results in a simple separation and purification process producing no carrier added Lu-177 or direct production Re-186 at high specific activity with decreased costs for separation (by dramatically decreasing resin quantities), decreased time required for separation, and drastically decreased waste volumes.
Markets
This invention is ideal for the radiopharmaceutical industry interested in reactor produced radioisotopes targeted with an expected demand to exceed 190,000 doses per year with a market value of $2,000-$5,000 per dose.
