The dertermination of trace elements in commerercial human serum albumin solutions by proton-induction x-ray emission spectrometry and neutron activation analysis

Particle-induced x-ray emission (p.i.x.e.) and neutron activation analysis (n.a.a.) are proposed for determining the trace element content of human serum albumin. Application of these methods to some commercial albumin solutions provided concentration data for up to 19 elements, most of which were present at a level below a few μg ml^-1. The precision of the p.i.x.e. technique, as determined by irradiating up to 20 targets from one sample, was about 3% for those elements where counting statistics were good. A comparison between the p.i.x.e. and n.a.a. results showed close agreement, indicating that p.i.x.e. can yield data which are accurate to within 10%. Neutron activation showed very good sensitivity for the elements producing long-lived nuclides (t_{$\text{1}\text{2}$} ? 3 days), but had rather high detection limits for the other elements, unless radiochemical separations were used.