Rapid assay procedures for tritium-labeled water in body fluids.

Abstract

Two methods are presented for the accurate radioassay of tritiated water in connection with body-water determinations. Both methods are applicable to body fluids in general. Considering factors of accuracy, simplicity, and time, the method of choice is rapid vacuum sublimation. This requires a 0.5 to 2 ml sample and is carried out in a single, individual glass unit. In cases where vacuum sublimation are not feasible, internal standardization will give results approaching similar accuracy provided an auxiliary determination is made of the water content of the original sample. For twelve active, healthy men the mean exchangeable bcdy water plus or minus 1 standard deviation was 51 plus or minus 5 l. Analogously body weight for this group was 102 plus or minus 9 kilograms. (auth)