Abstract: In a method of producing a carrier for a plurality of radioactive samples to be monitored in a liquid scintillation counter,wells are provided in a rigid plate (1) of a photon attenuating material in that holes disposed in a matrix configuration are covered from one side of the plate (1) by a first photon permeable foil (2),sample carrying cut-outs (3) from a sorption sheet on which samples have been deposited are placed in said wallsa scintillation fluid is added to the wells, andthe wells are sealed by a second permeable foil (4) to keep the cut-outs (3) and the scintillation fluid within the respective wells.