Complexes of technetium with polyhydric ligands

• Published in: The International journal of applied radiation and isotopes Vol. 36; no. 6; pp. 475 - 480
• Main Authors: Hwang, Lydia L.-Y., Ronca, Nicholas, Solomon, Nathan A., Steigman, Joseph
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier B.V 01.01.1985; New York, NY Pergamon Press
• Subjects: Biological and medical sciences; Investigative techniques, diagnostic techniques (general aspects); Medical sciences; Radionuclide investigations; Radionuclide study; Nuclear medicine; Polarography; Technetium Complexes; Ligand; Scintigraphic agent; Preparation; Electrophoresis; Absorption spectrum
• ISSN: 0020-708X
• DOI: 10.1016/0020-708X(85)90212-1

Polyhydric complexes of Tc(V) show absorption bands near 500 nm, with molar absorptivity coefficients of about 100. The shorter-chain compounds like ethylene glycol produce complexes which quickly disproportionate to Tc(IV) (as TcO 2) and Tc(VII) (asTcO 4 −) on acidification. The longer-chain ligands like mannitol and gluconate do not. However, while the mannitol complex shows no change in spectrum from pH 12 to pH 3, the gluconate and glucoheptonate compounds show a definite spectral change on acidification, starting at pH 5. Electrophoresis similarity showed a change in mobility with pH for Tc-glucoheptonate, but none for Tc-mannitol. It was concluded that the carboxylic acid group of glucoheptonate was not binding the technetium. In 25 molal choline chloride the glucoheptonate-Tc mole ratio was 1:1 or less. A similar result emerged from a similar experiment in methylcellosolve as solvent.