ABSTRACT
This chapter describes the theory and practice behind the detection and measurement of radioactivity using scintillation counting. Scintillation counting is inextricably linked to the instrumentation, with different manufacturers developing their own technologies and methods of data processing. Irrespective of the isotope, the principle of scintillation counting is the same: decay energy is converted to photons of light by a scintillator and it is the photons that are detected and measured. In liquid scintillation counting, energy from nuclear decay is transferred first to a solvent and then to a scintillator. Solid scintillators can be used in multiwell plates where multiple samples are analyzed simultaneously. In the mid-1980s, scintillation counters were developed around multiwell plate technology, where wells are arranged in a plastic plate to allow for multiple-sample analysis. The conversion process is linear and so during the counting of the sample the multichannel analyzer accumulates counts amounting to the complete energy spectrum of the radionuclide.
