Analytical quality control of chemical elements determination in dried samples of whole blood by ICP-OES and ICP-MS methods

摘要

Estimation of precision and accuracy of analytical determination of chemical elements content by combination of two methods (ICP-OES and ICP-MS) was made using the IAEA A-13 standard reference material (animal blood) as the subject. It was shown that 100 mg is the optimal weighting for such analyses. Duplicated analysis of 100mg samples with relative uncertainty below ±10% allows to estimate mass fraction of only 10 elements: Ba, Ca, Cu, Fe, K, Mg, P, Rb, Sr and Zn. In the same conditions but with the relative uncertainty being within ±20-30% the ICP-MS method allows to determine seven more elements: Ga, Ge. I, Li, Mn, Pb and Se. The obtained mean values of mass fractions for most of the chemical elements were within the certificate's 95% confidence interval or close to it, indicating satisfactory measurements accuracy. The only exception was selenium, in whose case the obtained mean value of mass fraction was 2.5 times higher than the certified one.