Trace elements analysis in biological samples by proton nuclear activation

A method for the multielemental analysis of trace elements in biological samples by medium energy proton nuclear activation (PNA) has been developed. The response linearity, reproducibility and reliability of the method have been tested by a set of preliminary measurements. Results concerning the quantitative determination of the concentrations of Sr, Cu, Fe, Zn and Se in human serum are presented. Activation was induced with a 23 MeV proton beam from the AVF cyclotron of the University of Milan, by means of (p, 2n) reactions on the nuclei of the elements under study. The quantitative determination was obtained by an internal reference method and by comparison with a standard sample of serum doped with known quantities of the elements of interest. A clinical investigation of the zinc content of serum in children has been performed.