In this section
@article{Osborne:2026:10.1039/d6qi01035k,
author = {Osborne, BE and Siakalli, C and Brown, RK and White, AJP and Rocco, C and Weiss, D and Delgado-Pinar, E and García-España, E and Sosabowski, JK and Ma, MT and Long, NJ},
doi = {10.1039/d6qi01035k},
journal = {Inorg Chem Front},
title = {Picolinamide-functionalized macrocyclic chelators for 203/212Pb theranostic radiotracers.},
url = {http://dx.doi.org/10.1039/d6qi01035k},
year = {2026}
}
TY - JOUR
AB - Picolinamide-functionalized macrocyclic ligands represent a promising class of chelators for 203/212Pb-based theranostic applications, offering a dual role in both diagnostic imaging and targeted radiotherapy. In this study, two 18-membered diazacrown ligands, K22_PicAm and the novel NPK_PicAm, were synthesized and complexed with both non-radioactive Pb2+ and radiotherapeutic 212Pb2+. Structural characterization via NMR spectroscopy and X-ray diffraction confirmed the formation of a single, highly rigid, symmetric [Pb(K22_PicAm)]2 + species. Density Functional Theory (DFT) and Natural Bond Orbital (NBO) analysis indicated stereochemically inactive 6s2 lone pairs in the Pb2+ complexes, leading to holodirected geometries. UV-vis spectroscopy and potentiometric titrations showed both ligands form highly stable Pb2+ complexes, with complete binding by K22_PicAm and NPK_PicAm between pH 4 and 9. Radiolabelling studies with 212Pb demonstrated near-quantitative radiochemical conversion within 15 minutes. These results establish picolinamide-bearing macrocycles as promising candidates for the development of next-generation, targeted 203/212Pb theranostic agents and support their further exploration in radiopharmaceutical research.
AU - Osborne,BE
AU - Siakalli,C
AU - Brown,RK
AU - White,AJP
AU - Rocco,C
AU - Weiss,D
AU - Delgado-Pinar,E
AU - García-España,E
AU - Sosabowski,JK
AU - Ma,MT
AU - Long,NJ
DO - 10.1039/d6qi01035k
PY - 2026///
SN - 2052-1553
TI - Picolinamide-functionalized macrocyclic chelators for 203/212Pb theranostic radiotracers.
T2 - Inorg Chem Front
UR - http://dx.doi.org/10.1039/d6qi01035k
UR - https://www.ncbi.nlm.nih.gov/pubmed/42327914
ER -
Professor Nick Long
Email: n.long@imperial.ac.uk
Telephone: +44 (0)20 7594 5781
501J
Molecular Sciences Research Hub
White City Campus
