Radionuclides therapeutical applications

Metals continue to play an important role in radiopharmaceuticals for diagnostic and therapeutic applications in nuclear medicine. Radiopharmaceuticals are drugs that contain a radionuclide and are used for imaging if the radionuclide is a photon emitter (gamma (7) or positron (/3+)) or for... 

Radiotherapy generally involves cell destruction, requiring some form of particle emission on decay and a half-life between 1 and 10 days. The choice of a particular therapeutic application determines the type of particle emission (a, ft, or Auger e ), and the energy and half-life of the radionuclide to be used. Considerations include time for delivery of the radiopharmaceutical to its in vivo target, location of the target (tumor surface, tumor cell cytoplasm, tumor cell nucleus) and size of the tumor. The reader is directed to a number of reviews on this subject.15-22... 

Rh is a ft emitting radionuclide suitable for therapeutic applications. It has a 35.4-h half-life and emits 0.566 MeV and 0.248 MeV ft particles and a 319 keV gamma photon. It is a reactor-produced radionuclide that is also potentially available from the separation of fission products in... 

Coordination compounds have the potential to be used in both diagnostic and therapeutic applications, but only the former have been extensively developed so far. This reflects the differing nature of the two types of application. In diagnosis it is only necessary to detect the location of the radionuclide in the body. Since extremely sensitive devices are available for the detection of ionizing radiation, useful diagnostic information may be obtained with relatively low patient... 

Labelled compounds have found broad application in various fields of science and technology. A great variety of labelled compounds are applied in nuclear medicine. The compounds are produced on a large scale as radiopharmaceuticals in cooperation with nuclear medicine, mainly for diagnostic purposes and sometimes also for therapeutic application. The study of metabolism by means of labelled compounds is of great importance in biology. More details on the application of radionuclides and labelled compounds in medicine and other areas of the life sciences will be given in chapter 19. 

It is an attractive object of research to synthesize labelled compounds that are taking part in specific biochemical processes or able to pass specific barriers in the body, with the aim of detecting malfunctions and of localizing the origin of diseases. Complexes of short-lived no-carrier-added radionuclides and high yields of the syntheses are of special interest. In the case of short-lived radionuclides, such as fC, the synthesis must be fast and as far as possible automated. Labelled organic molecules can also be used to transport radionuclides to special places in the body for therapeutical application, i.e. as specific internal radiation sources. 

In general, p - and p" -Particles penetrate deep into the medium however, they do not cause damage to tissues and organs. Radionuclides that decay by p-Particle emissions are used very extensively in nuclear medicine for diagnostic and therapeutic applications. Positron-emitting nuclides are used in nuclear medicine for diagnostic purposes. p+-Emitting radionuclides are under active study for use in radiotherapy. An example... 

J.H. Lawrence, the brother of Ernest, made the first clinical therapeutic application of an artificial radionuclide when he used phosphorus-32 to treat leukemia, 1936. 

Specific activity is an important parameter since in many cases, the availability of very high specific activity or carrier-firee radionuclides is required for biological applications. One example of the importance of high specific activity is the radiolabeling of tumor-specific antibodies or peptides for both diagnostic and therapeutic applications where only very small amounts of the radiolabeled antibodies are administered to ensure maximal uptake at the limited tumor cell surface antigen sites. 

Only a few of the p emitters Usted in O Table 46.4 have been investigated for therapeutic applications. Many of these radionuclides are reactor produced, limiting the types of carrier molecules for which they are suitable. Several radiocolloids labeled with Au have been studied for intracavitary therapies however, their relatively high degree of leakage from the treatment site has limited their clinical utility (Virkkunen et al. 1967 Spencer 1978 Harbert 1987). Treatment ofbone pain with polyphosphate complexes of both and has been... 

R. E. Weiner, M. L. Thakur, Metallic Radionuclides Applications in Diagnostic and Therapeutic Nuclear Medicine, Radiochim. Acta 70/71, 273 (1995)... 

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