Radiochemistry and Radiopharmacy.

In modern pharmaceutical development and medicine, radioactivity has an increasing impact in the field of diagnostic applications (in vitro and in vivo) as well as in therapeutic applications (Qaim and Coenen 2005; Stöcklin et al. 1995). Regarding these different forms of applications, radionuclides must be used with respect to their modes of decay. For single photon emission computed tomography (SPECT), radionuclides with a short (hours to several days) half-life and accompanying gamma emission in the range of 70-250 keV are the most useful. In addition, emission of only one photon per decay is of advantage, but not a must. The gamma emission has to be strong enough to easily penetrate the body barrier and also has to be well detectable by the common SPECT camera systems. Such radionuclides are commonly found among those with the decay mode of electron capture (EC) or internal conversion (IC). [ABSTRACT FROM AUTHOR]