Possibility of measuring multiply labelled samples by Cherenkov spectrometry

The activity of multiply labelled samples can be measured by the overlap technique on the basis of the Cherenkov effect only in the case of two or rarely three isotopes, having beta- energies different enough. Though the colour filters change the shape of the energy spectra of beta-isotopes, the overlap tecnique cannot be used more favourably. It is best to use the influence of filters on the efficiency. Measuring with and without filters, it is possible to determine the activity of two or three isotopes separately in one sample. (Author)