Proton, photon and neutron activation analysis for the determination of stable isotopes of gadolinium in human blood plasma

The biokinetics of radioactive substances can be studied using stable trace rs. For the highly radiotoxic actinides, for which no stable isotopes are a vailable as tracers, the use of stable isotopes of lanthanides as chemicall y related surrogates has been suggested. In this work, the possibility of u sing activation analysis with protons, photons, or thermal neutrons for the determination of single stable isotopes of gadolinium in biological sample s has been tested. All the techniques show very good linearity response, an d may be considered as complementary. Whereas activation analysis with prot ons is recommendable for the simultaneous determination of two different is otopes, neutron and photon (gamma) activation analysis should be chosen whe never a better sensitivity or simplicity of the analysis is required.