Dosage par radioactivation neutronique in vivo de quelques eléments contenus dans l'organisme du rat

Abstract

The possibility is examined of combined analysis for calcium, phosphorus, nitrogen and chlorine in the adult rat by neutron activation in vivo. The particles are produced by a 400-kV, 2-mA SAMES accelerator giving a neutron output at 14 MeV of the order of 1 × 10 11n. cm −2s −1 in 4 π. The animals are placed in a rotating device surrounded by paraffin wax (which presents a thickness of 7 cm to intercept the incident neutron beam) and are irradiated for 10 min. The mean flux of 14-MeV neutrons measured at the surface of the cylindrical box containing the rat is 7·5 × 10 6 n.cm −2s −1 and the thermal flux is 1·1 × 10 7 n.cm −2s −1. The radioactivity of the elements 49Ca, 13N, 38Cl and 28Al was measured with a NaI (Tl) crystal measuring 7·5 × 7·5 cm (in certain experiments a NaI (Tl) crystal of 20 × 15 cm was used). Various sources of error (parasitic nuclear reactions which may interfere with the elements under analysis, reproducibility of results) under the chosen operating conditions are examined. The results obtained with 16 rats are compared with the data reported in the literature.