Preclinical Evaluation of a Lead Specific Chelator (PSC) Conjugated to Radiopeptides for ²⁰³Pb and ²¹²Pb-Based Theranostics.

ABSTRACT: ²⁰³Pb and ²¹²Pb have emerged as promising theranostic isotopes for image-guided α-particle radionuclide therapy for cancers. Here, we report a cyclen-based Pb specific chelator (PSC) that is conjugated to tyr³-octreotide via a PEG₂ linker (PSC-PEG-T) targeting somatostatin receptor subtype 2 (SSTR2). PSC-PEG-T could be labeled efficiently to purified ²¹²Pb at 25 °C and also to ²¹²Bi at 80 °C. Efficient radiolabeling of mixed ²¹²Pb and ²¹²Bi in PSC-PEG-T was also observed at 80 °C. Post radiolabeling, stable Pb(II) and Bi(III) radiometal complexes in saline were observed after incubating [²⁰³Pb]Pb-PSC-PEG-T for 72 h and [²¹²Bi]Bi-PSC-PEG-T for 5 h. Stable [²¹²Pb]Pb-PSC-PE

SUBMITTER: Li M 

PROVIDER: S-EPMC9966725 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature