[en] A method of analysing a sample by scintillation counting comprises radioactively tagging a sample for assay, subjecting the same to liquid chromatography, and subjecting the fraction so collected to scintillation counting characterized in that the chromatographic fractions are evaporated to dryness and subsequently taken up in a scintillation fluid prior to counting. 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. There is reference to measurement of the binding of radioactive alkylating carcinogens to nucleic acids in tissues. (author)