(99m)Tc complexes with activated ester functions; ligands comprising a 3,4-diamino-benzoate backbone

Nuclear Medicine and Biology
Osmar Calderon SanchezM Eisenhut


Preformed (99m)Tc chelates with an activated ester function are useful for the gentle labeling of proteins (precomplexation route). In this context, new heterobifunctional ligands derived from 2,3,5,6-tetrafluorophenyl (TFP) 3,4-diamino-benzoates (OC1, OC3, OC4) were synthesized. Their corresponding (99m)Tc-complexation and protein-conjugation characteristics were elucidated and compared with the results previously reported using 2,3,5,6-tetrafluorophenyl N-(S-benzoylthioacetyl)glycylglycyl-p-aminobenzoate (OC2). The reaction temperatures and the reaction time markedly influenced complexation yields. Compared with OC2, the (99m)Tc-chelate formation with OC1 and OC4 was more effective, showing radiochemical yields of 60% and 70% within 20 min, respectively. Owing to steric hindrance, the complexation of OC3, however, did not exceed 10%. No-carrier-added (99m)Tc complexes were conjugated at pH 10 with the anti-EGF-receptor monoclonal antibody MAb425, resulting in labeling yields of 14% for (99m)Tc-OC1 and 7% for (99m)Tc-OC4 after incubating for 20 min at 30 degrees C. Increasing the temperature to 40 degrees C improved these results by 14% and 3%, respectively. As compared with (99m)Tc-OC2, which provides the chelating substituen...Continue Reading


Jan 1, 1992·Journal of Medicinal Chemistry·Y OhmomoH F Kung
Jan 1, 1988·International Journal of Radiation Applications and Instrumentation. Part A, Applied Radiation and Isotopes·W BrandauD M Taylor
Jun 1, 1988·Proceedings of the National Academy of Sciences of the United States of America·A R FritzbergD S Wilbur
Nov 17, 1998·Bioconjugate Chemistry·T W Spradau, J A Katzenellenbogen
Jun 5, 2002·Annals of Nuclear Medicine·Yasushi Arano
Jun 29, 2002·Nuclear Medicine and Biology·K VerbekeA Verbruggen

❮ Previous
Next ❯


Jan 26, 2012·Metallomics : Integrated Biometal Science·Cécile ClavaudChristophe Dugave

❮ Previous
Next ❯

Related Concepts

Related Feeds

Cancer Imaging

Imaging techniques, including CT and MR, have become essential to tumor detection, diagnosis, and monitoring. Here is the latest research on cancer imaging.