title: 2,3,5,6-Tetrafluorophenyl N-(S-benzoylthioacetyl)glycylglycyl- p-aminobenzoate, a heterobifunctional (99m)Tc ligand for precomplexed antibody labeling.
abstract: Heterobifunctional (99m)Tc ligands are useful for antibody labeling using the precomplexation route. The aim of this work was to synthesize a ligand, which has sufficient chemical stability to be complexed with (99m)Tc without inactivating the reactive conjugation group. Using 2,3,5,6-tetrafluorophenyl N-(S-benzoylthioacetyl)glycylglycyl-p-aminobenzoate (OC2) >60% of the (99m)Tc complex was obtained at 80 degrees C in 20 min, which was separated from the free ligand and impurities by HPLC. After solvent evaporation, (99m)Tc-OC2 was conjugated with the monoclonal antibody mAb425 in 50% radiochemical yield. In all, the labeling method required about 1 h preparation time. The immunoreactive fraction of the (99m)Tc-OC2 mAb425 conjugate was 81%, indicating preserved binding capability after conjugation. Compared to recently described methods, which need in situ activation of the (99m)Tc complex, the application of OC2 saved time and reduced the number of manipulations with radioactive material.
authors: Department of Nuclear Medicine, University of Heidelberg, Heidelberg, Germany.
authors: O
authors: O
authors: Calderon Sanchez
authors: A
authors: A
authors: Mohammed
authors: W
authors: W
authors: Mier
authors: K
authors: K
authors: Graham
authors: J
authors: J
authors: Schuhmacher
authors: S O
authors: SO
authors: Arndt
authors: U
authors: U
authors: Haberkorn
authors: R
authors: R
authors: Mocelo
authors: M
authors: M
authors: Eisenhut
mesh_terms: D010129:4-Aminobenzoic Acid / Q000138:chemical synthesis / Q000378:metabolism*; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000378:metabolism*; D002294:Carcinoma, Squamous Cell; D006801:Humans; D007553:Isotope Labeling; D008024:Ligands; D015394:Molecular Structure; D019275:Radiopharmaceuticals / Q000138:chemical synthesis / Q000378:metabolism*; D013667:Technetium / Q000378:metabolism*; D013696:Temperature; D062366:para-Aminobenzoates
chemical_list: C487559:2,3,5,6-tetrafluorophenyl N-(S-benzoylthioacetyl)glycylglycyl- p-aminobenzoate; D000911:Antibodies, Monoclonal; D008024:Ligands; D019275:Radiopharmaceuticals; D062366:para-Aminobenzoates; D013667:Technetium; D010129:4-Aminobenzoic Acid