US 12,312,653 B2
Systems and methods for generating lead
Edwin A Sagastume, Iowa City, IA (US); Michael K. Schultz, Hills, IA (US); Daniel McAlister, Downers Grove, IL (US); Andrew W. Knight, Albuquerque, NM (US); and Madeleine Eddy, Lisle, IL (US)
Assigned to PERSPECTIVE THERAPEUTICS, INC., Seattle, WA (US)
Filed by PERSPECTIVE THERAPEUTICS, INC., Seattle, WA (US)
Filed on Aug. 15, 2024, as Appl. No. 18/806,298.
Claims priority of provisional application 63/519,817, filed on Aug. 15, 2023.
Prior Publication US 2025/0059621 A1, Feb. 20, 2025
Int. Cl. C22B 3/00 (2006.01); B01D 15/18 (2006.01); B01D 15/36 (2006.01); B01D 15/42 (2006.01); C22B 3/02 (2006.01); C22B 3/42 (2006.01)
CPC C22B 13/04 (2013.01) [B01D 15/1814 (2013.01); B01D 15/362 (2013.01); B01D 15/426 (2013.01); C22B 3/02 (2013.01); C22B 3/42 (2013.01)] 25 Claims
OG exemplary drawing
 
1. A system for separating a lead radioisotope from a mixture comprising lead radioisotope and a radium isotope or a thorium isotope, the system comprising a first, a second, a third and a fourth cartridge in series with one another, each of the first, second, third and fourth cartridges having an inlet, an outlet and a chamber therebetween containing chromatographic media, wherein
(a) the first cartridge chamber contains a first chromatographic media comprising lead-complexing media that (i) preferentially binds the lead radioisotope over radioisotopes of radium and thorium in the presence of a first loading solution having a pH, pH1L, and containing the mixture, and (ii) elutes the lead radioisotope in the presence of a first eluent comprising a weak acid and having a pH, pH1E, to form a first eluate comprising the lead radioisotope dissolved in the first eluate, wherein pH1E is greater than pH1L,
(b) the second cartridge chamber contains a second chromatographic media comprising a weak cationic exchange media, the weak cationic exchange media comprising carboxylic acid and/or carboxylate groups, that (i) preferentially binds the lead radioisotope over radioisotopes of radium and thorium from a second loading solution comprising a weak acid and having a pH, pH2L, and (ii) elutes the lead radioisotope in the presence of a second eluent comprising a mineral acid and having a pH, pH2E, to form a second eluate comprising the lead radioisotope dissolved in the second eluate, wherein pH2L is greater than pH2E,
(c) the third cartridge chamber contains a third chromatographic media comprising a strong cationic exchange media, the strong cationic exchange media comprising sulfonic acid and/or sulfonate groups, that (i) preferentially binds radioisotopes of radium or thorium over the lead radioisotope in the presence of a third loading solution comprising a mineral acid and containing the second eluate, thereby separating the radioisotope of radium or thorium from the third loading solution, and (ii) passes through the lead radioisotope in the third loading solution to form a third lead-containing solution having the lead radioisotope dissolved therein and having a reduced content of the radioisotope of radium or thorium as compared to a content of the radioisotope of radium or thorium in the second eluate, and
(d) the fourth cartridge chamber contains a fourth chromatographic media comprising lead-complexing media that (i) preferentially binds the lead radioisotope over radioisotopes of radium and thorium in the presence of a fourth loading solution having a pH, pH4L, and (ii) elutes the lead radioisotope in the presence of a fourth eluent having a pH, pH4E, wherein pH4E is greater than pH4L, and
(e) the outlet of the first cartridge is fluidly connected to the inlet of the second cartridge, such that the first eluate from the first cartridge flows directly into the second cartridge, and the outlet of the second cartridge is fluidly connected to the inlet of the third cartridge, such that the second eluate from the second cartridge flows directly into the third cartridge.