Radiolabeling and in vitro studies of scandium-44 with HOPO chelator for PET imaging

Journal Article · Wed Dec 07 23:00:00 EST 2022 · Nuclear Medicine and Biology

DOI:https://doi.org/10.1016/s0969-8051(22)02196-5· OSTI ID:1958591

Gajecki, Leah ^[1]; Bhupathiraju, N.V.S. Dinesh ^[2]; Phipps, Michael ^[3]; Cutler, Cathy ^[1]; Francesconi, Lynn ^[2]; Deri, Melissa ^[4]; Sanders, Vanessa ^[1]

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1. Brookhaven National Lab. (BNL), Upton, NY (United States)
2. City Univ. of New York (CUNY), NY (United States). Hunter College
3. Memorial Sloan Kettering Cancer Center, New York, NY (United States). Sloan Kettering Institute; City Univ. of New York (CUNY), NY (United States). Hunter College
4. City Univ. of New York (CUNY), NY (United States). Lehman College

⁴⁴Sc has been attracting interest as a clinically viable PET (positron emission tomography) imaging radionuclide due to its high positron branching ratio, 3.97 hour half-life, ideal positron energy of 632 keV and ability to be produced from a generator as well as from a cyclotron. Scandium is also of interest since the coordination is similar to the lanthanides and Ga³⁺ that have demonstrated labeling methods. Further, ⁴⁷Sc (a potential therapeutic radionuclide) can serve as a matched isotope pair for theranostic applications. While the labeling studies of ⁴⁴Sc with DOTA and DOTA derivatives are quite extensive, there is little data on complexation of scandium with the chelator 3,4,3-(LI-1,2-HOPO). This ligand has been used successfully to radiolabel ⁸⁹Zr where it was shown to have high stability in vivo. Additionally, preliminary studies with ⁸⁶Y, and non-radioactive scandium show promising complexation constants similar to those found with DOTA derivatives. One major advantage of using HOPO is that radiolabeling can be achieved at room temperature while DOTA requires elevated temperatures, that may be detrimental when radiolabeling biomolecules. Radiolabeling of generator produced ⁴⁴Sc versus cyclotron produced ⁴⁴Sc is also under investigation as there are currently several different post-elution purification methods of generator ⁴⁴Sc, and the potential radiolabeling complications of these eluents has not yet been studied. This work focuses on radiolabeling HOPO with generator produced ⁴⁴Sc and the in vitro and radioanalytical evaluation of the resulting complexes.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP)
• Grant/Contract Number: SC0012704
• OSTI ID: 1958591
• Report Number(s): BNL-224068-2023-JAAM
• Journal Information: Nuclear Medicine and Biology, Journal Name: Nuclear Medicine and Biology Vol. 114-115; ISSN 0969-8051
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE