A Novel Organometallic Aqua Complex of Technetium for the Labeling of Biomolecules: Synthesis of [99mTc(OH2)3(CO)3]+ from [99mTcO4]- in Aqueous Solution and Its Reaction with a Bifunctional Ligand

99mTc-Labeled Small Peptides as Diagnostic Radiopharmaceuticals.

Basic aqueous chemistry of [M(OH2)3(CO)3]+ (M=Re, Tc) directed towards radiopharmaceutical application

Stable one-step technetium-99m labeling of His-tagged recombinant proteins
with a novel Tc(I)–carbonyl complex

Stable one-step technetium-99m labeling of His-tagged recombinant proteins with a novel Tc(I)-carbonyl complex.

Uptake of the cationic compound hexakis(2-methoxyisobutylisonitrile)-technetium-99m ([99mTc]MIBI) was examined in nine human tumor cell lines. The concentration of [99mTc]MIBI after a 1-h incubation with the compound varies from 5 to 28% of the activity in the external medium. In contrast, normal V79 cells (Chinese hamster lung fibroblasts) and human peripheral blood mononuclear cells exhibit a minimal uptake of less than 2% of the activity in the medium. Kinetic experiments with SW-13 cells indicate a rapid uptake over time (t½ of 10 min) until a steady state is approached whose concentration appears directly correlated with the extracellular concentration of [99mTc]MIBI with no evidence of saturation over the range tested (10-12-10-9m). [99mTc]MIBI is taken up by a temperature dependent process that is restricted to living cells. Microautoradiography demonstrates that [99mTc]MIBI is clustered in the cytoplasm around the nucleus. Given that depolarizing the plasma membrane potential in high K+ buffer results in lowering the uptake of [99mTc]MIBI and that alteration of the mitochondrial membrane potential with valinomycin or nigericin induces, respectively, a significant decrease or increase of [99mTc]MIBI uptake, we propose that the plasma and mitochondrial membrane potentials play a major role in the uptake. These data suggest that the γ emitter [99mTc]MIBI exhibits interesting tumor cell interaction characteristics with promise for in vivo tumor imaging.

https://cancerres.aacrjournals.org/content/canres/50/7/2198.full.pdf

Uptake of the Cation Hexakis(2-methoxyisobutylisonitrile)-Technetium-99m by Human Carcinoma Cell Lines in Vitro

The complexes, hexakis(alkyl isocyanide) technetium(I) hexafluorophosphate (Tc(CNR)/sub 6/)PF/sub 6/ (where R = tert-butyl, methyl, cyclohexyl, and phenyl), have been prepared by reduction of the pertechnetate ion with aqueous sodium dithionite (Na/sub 2/S/sub 2/O/sub 4/) in the presence of the isocyanide ligands. These complexes have been characterized by elemental analysis, optical, ir, and /sup 1/H NMR spectroscopy, conductance, cyclic voltammetry, and field desorption mass spectrometry.

Henrianna Pang

Papers

Synthesis and characterization of hexakis(alkyl isocyanide) and hexakis(aryl isocyanide) complexes of technetium(I)