The dose absorbed by lymphocytes irradiated in vitro with tritiated water

A simple method of irradiating cells in vitro with beta particles is to add the beta-emitter to a cell suspension; various dosimetric aspects of this procedure have been investigated. It is shown that, due to the different water content of the various constituents of a blood cell suspension, the average dose D beta absorbed by a certain type of cells for a tritium nominal concentration Co and an irradiation time t is given by D beta(t) = KEnCo eta t. Typical values of the factor eta are calculated for lymphocytes. A series of experiments has demonstrated that whilst the uptake phase has negligible effect on the dose, a significant error may arise during washing-out because a proportion of the activity remains in the cells.