Analysis of triple-labeled samples by multivariate liquid scintillation counting

The radioassay of samples containing three pure beta emitters having various activity ratios has been performed by using the most probable value theory applied to liquid scintillation detection. The principle of the technique is based on experimentally generating simultaneous equations more than the radionuclides to be analyzed. This technique requires a liquid scintillation counter and sets of quenched radionuclide standards. The present technique has been applied successfully to the case of 3 H- 35 S- 36 Cl in composite mixtures.