Targeted alpha-therapy(TAT)is increasingly attractive due to its extraordinary antitumor efficacy.How-ever,the supply of α-emitters for TAT is insufficient and under control by a limited number of countries.212Pb is a promising α-emitter with an optimal half-life(10.6 h)and favored decay chain.Of interest,212 Pb can be extracted directly from natural thorium,which may be abundant in the mining waste of rare-earth,uranium,etc.Indeed,radioactive thorium waste has been a longstanding environmental chal-lenge that needs immediate action.Developing an on-demand and facile process to isolate 212Pb from natural thorium would be ideal to meet the above challenges,yet is difficult.In theory,the ratio of 212Pb to natTh is below 10-13 in commercially available thorium salts.As a pilot study,2.2 MBq of 212Pb was suc-cessfully extracted from a 5 L solution of thorium nitrate by using a Pb-selective resin.The radiochemical purity of212Pb is over 99.9％according to gamma-ray analysis.The purified 212Pb was applied to radiola-bel a couple of peptides used in clinics(i.e.PSMA,TATE and FAPI-04),and the radiochemical yields are＞85％.Of note,212Pb can be repeatedly separated from the thorium solution every 2 days.In summary,a practical and scalable method was developed to isolate 212Pb for potentially clinical use,which may be of great importance as it does not require either cyclotron or nuclear reactor.

Junyi Chen;Mengxin Xu;Yu Liu;Dongban Duan;Yuxiang Han;Zhibo Liu

Beijing National Laboratory for Molecular Sciences,Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental Science,College of Chemistry and Molecular Engineering,Peking University,Beijing 100871,China;Peking-Tsinghua Center for Life Sciences,Peking University,Beijing 100871,China

中国化学快报（英文版）

[1]Junyi Chen;Mengxin Xu;Yu Liu;Dongban Duan;Yuxiang Han;Zhibo Liu-.Isolation of 212Pb from natural thorium for targeted alpha-therapy)[J].中国化学快报（英文版）,2022(07):3474-3477

212Pb,natTh,of212Pb,radiola

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