Technetium compounds, radiochemical

Caution. "Tc is a weak beta emitter ( max = 0.3 meV f1/2 = 2.12 x 105 yr). Technetium compounds should be handled in a well-ventilated fume hood, and normal radiochemical practices should be observed. 

Abstract This review presents a comprehensive overview of the most significant developments in the chemistry of technetium and rhenium complexes anchored by heterofunc-tionalized phosphines and by hard and soft scorpionates. The main goal is to provide the reader with chemical,radiochemical and biological knowledge which is expected to enhance the application of these types of compounds in the development of target-specific radiopharmaceuticals. 

Given a method of preparing Mo organometallic compounds, the p decay transformation of Mo to Tc could be studied. The decay of Mo to Tc yields a nuclide with much lower recoil energy than that formed in the molybdenum (n, y ) process. However, this decay produces a cascade of Auger electrons see Auger Spectroscopy) which can cause bond disruption. These studies are difficult, because the technetium-99m product is produced at radiochemical tracer levels. Macroscopic quantities of products are not available for spectroscopic characterization. 

Neirinckx RD, Canning LR, Piper IM, Nowotnik DP, Pickett RD, Holmes RA, Volkert WA, Forster AM, Weisner PS, Mariott JA, Chaplin SB (1987) Technetium-99m d,l-HM-PAO a new radiopharmaceutical for SPECT imaging of regional cerebral blood perfusion. J Nucl Med 28 191-202 Noll B, Seifert S, Muenze R (1980) New Tc(IV) compounds with nitrilo-triacetic acid. Radiochem Radioanal Lett 43 215-218... 

To prepare the compounds RbioTe68i4, CsioTe68i4, RbioRe68i4, and CsioReeSn, a mixture of the alkali carbonate and rhenium or technetium in 5 1 molar ratio was in each case converted at 800 °C in a stream of hydrogen doped with sulfur. The duration of these reactions was between 10 and 16 h. The preparation of the technetium compoimds was performed in a radiochemical laboratory of the For-schungszentrum Julich. The Tc isotope used decomposes by emission. The compounds were obtained as black, lustrous crystals embedded in the partially solidified melt (Fig. 2). All four sulfides are unstable in air. 

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