Measurements of 133Xe Activity in Blood Sampled in Plastic and Glass Syringes

Samples of 133Xe in saline and blood were measured in 2-ml syringes of plastic and glass by different detectors. Good reproducibility with a coefficient of variation of 2% and good accuracy under varying conditions were obtained by a well scintillator with side hole and by a flat end scintillator with 6 cm distance to the sample. Despite the high uptake of xenon in the wall of the plastic syringes and their significant loss of activity of about 0.5 % per hour, they were for other reasons preferred to glass syringes.