Technetium generation

R. E. Boyd, Technetium Generators Status and Prospects, Radiochim. Acta 41, 59 (1987)... 

Briner WH, Harris CC (1974) Radionuclide contamination of eluates from fission-product molybdenum-technetium generators. J Nucl Med 15 466-467 Council of Europe (2005 a) Sodium pertechnetatel Tc] injection (fission). Monograph No. 124. 

Radiopharmaceuticals containing c produced from molybdenum-technetium generators represent an additional somce of c to the environment. The... 

Most radioisotopes used in nuclear medicine are artificial. They are produced in nuclear reactors (e.g. Sr, Co), cyclotrons (e.g. C, F) or specialized generators such as a molybdenum-technetium generator. The metastable radioisotope ""Tc has a half-life of 6 hours and is important for medical imaging. It is a decay product of Mo - 2.8 days), which is itself man-made, being produced in a nuclear reactor. The radioactive decay of Mo to Tc and the much longer lived Tc is summarized below ... 

Technetium-99m is an ideal radioisotope for scanning organs because it has a half-hfe of 6.0 h and is a pure gamma emitter. Suppose that 80.0 mg were prepared in the technetium generator this morning. How many miUigrams... 

Technetium-99m (the m signifies a metastable, or moderately stable, species) is generated in nuclear reactors and shipped to hospitals for use in medical imaging. The radioisotope has a half-life of 6.01 h. If a 165-mg sample of technetium-99m is shipped from a nuclear reactor to a hospital 125 kilometers away in a truck that averages 50.0 kmh. what mass of technetium-99m will remain when it arrives at the hospital ... 

Rhenium (75) was discovered in 1925 by Ida Tacke and Walter Noddack as the last naturally occurring element. The first artificially produced element was identified by Emilio G. Segre in 1937. Ernest Lawrence detected technetium in a molybdenum sample, which he had bombarded in his cyclotron. All elements discovered since then have been generated artificially. 

Complexation studies with bidentate phosphine ligands showed that stable cationic complexes of Tc(V), Tc(III), and Tc(I) are easily accessible. The influence of reaction conditions on reaction route and products is well demonstrated by the reaction of pertechnetate with the prototype 1,2-bis(dimethylphosphino)-ethane (dmpe) (Fig. 16). Careful control of reduction conditions allows the synthesis of [Tc02(dmpe)2]+, [TCl2(dmpe)2]+, and [Tc(dmpe)3]+, with the metal in the oxidation states V, III, and I [120,121]. This series illustrates the variety of oxidation states available to technetium and their successive generation by the action of a 2-electron reducing agent. 

Figure 7.10 Technetium-99m generator. (Adapted from references 88 and 89.)...

Chan, H-K., Daviskas, E., Eberl, S., Robinson, M., Bautovich, G., and Young, I.H., Deposition of aqueous aerosol of technetium-99m diethylenetriamine pentaacetic acid generated and delivered by a novel system (AERx) in healthy subjects, Eur. J. Nucl. Med., 26 320-327 (1999). 

It was the first new element to be produced artificially from another element experimentally in a laboratory. Today, all technetium is produced mostly in the nuclear reactors of electrical generation power plants. Molybdenum-98 is bombarded with neutrons, which then becomes molybdenum-99 when it captures a neutron. Since Mo-99 has a short half-life of about 66 hours, it decays into Tc-99 by beta decay. 

Special attention has been paid to Re, since this isotope can readily be obtained from isotope generators which are based on the decay of (physical ti/2 = 69.4 d) in a matrix from which the daughter nuclide Re can readily be separated. This permits continuous availability of the radioisotope at the clinic and allows the preparation of Re-radiopharmaceuticals in a kit procedure as has been established for technetium radiopharmaceuticals. W/ Re generators... 

The field of nuclear medicine has grown tremendously in the last two decades largely as a result of the development of the Mo-99/Tc-99m generator system. The ready availability of Tc-99m created a mushrooming interest in nuclear medicine clinical and research activity. Technetium-99m in a variety of forms is annually used in millions of nuclear medicine procedures performed worldwide. During recent years there has been a significant increase in interest in very short-lived (<30 min)... 

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