title: The influence of reducing agents on the composition of 99Tc-complexes: implications for 99mTc-radiopharmaceutical preparation.
abstract: The use of formamidine sulphinic acid as a reducing agent in the presence of technetium-99-pertechnetate and diethyldithiocarbamate ligand has been shown to yield a complex containing a Tc = CO bond. The carbon monoxide present in this complex originates from the reducing agent itself. Evidence is presented which suggests that this carbonyl complex is present in the 99mTc-diethyldithiocarbamate preparation obtained by the use of formamidine sulphinic acid as the reducing agent. Use of hydrazine as a reducing agent yields a complex containing a Tc = N bond. It is apparent that when reducing agents such as hydrazine or formamidine sulphinic acid are used in the preparation of 99mTc-radiopharmaceuticals, the possibility of the formation of complexes structurally different to those obtained by the use of stannous chloride must be considered.
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D004050:Ditiocarb; D006834:Hydrazines; D008024:Ligands; D015609:Organotechnetium Compounds; D010084:Oxidation-Reduction; D011877:Radionuclide Imaging; D013441:Sulfinic Acids; D013667:Technetium; D013859:Thiocarbamates
chemical_list: D006834:Hydrazines; D008024:Ligands; D015609:Organotechnetium Compounds; D013441:Sulfinic Acids; D013859:Thiocarbamates; C034630:technetium Tc 99m diethyldithiocarbamate; C014561:formamidine sulfinic acid; D013667:Technetium; D004050:Ditiocarb