Improvements in and relating to a scintillation counting method and an evaporator for use therewith

Improvements to a scintillation counting method and an evaporator for use therewith is disclosed, which comprises radioactively tagging a sample for assay, subjecting the same to liquid chromatography, and subjecting the fraction so collected to scintillation counting characterised in that the chromatographic fractions are evaporated to dryness and subsequently taken up in a scintillation fluid prior to counting. The fraction may thus have a volume larger than the volumn of the scintillation fluid in which it is mixed. In a preferred embodiment of the invention an evaporator box is disclosed which provides means for directing a drying gas at a controlled temperature on the fraction in order to evaporate the same.