Thallium-201 (Lead-201) Separation

The are several isotopes of lead that are important in nuclear medicine. ²⁰¹Pb, produced by proton irradiation of isotopically enriched thallium targets, is the parent of ²⁰¹Tl used in heart scans.

Following dissolution of Tl targets in HNO₃, ²⁰¹Pb can be separated using Sr Resin and recovered in 6-8M HCl for further processing to recover the ²⁰¹Tl.

²⁰¹Tl can be separated from ²⁰¹Pb by oxidizing the Tl(I) to Tl(III) using HCl-H₂O₂ and retaining the Tl(III) chloride complexes on UTEVA Resin. The Pb(II) will not be retained in HCl and can be collected for ingrowth of additional ²⁰¹Tl. ²⁰¹Tl can then be recovered in normal saline with a small amount of ascorbic acid to reduce Tl(III) back to Tl(I).

Additional ²⁰¹Pb decontamination and removal of traces of organic material can be achieved by passing the ²⁰¹Tl solution through a small column of Alumina-R.