Multielement analysis of whole blood by high resolution inductively coupled plasma mass spectrometry

An analytical method using double focusing sector field inductively coupled plasma mass spectrometry (ICP-SMS) for rapid simultaneous determination of 50 elements in digested human blood is described. Sample preparation consisted of microwave digestion with nitric acid followed by dilution with ultrapure water. The importance of controlling possible contamination sources at different sample preparation and analysis stages in order to achieve adequate method detection limits (MDL) is emphasised. Correction for matrix effects was made using scandium, indium and lutecium as internal standards. Accuracy of the data for elements suffering from spectral interferences was improved by applying either a high resolution capability of the ICP-SMS or mathematical corrections. Different approaches for accuracy assessment in blood analysis are evaluated. Additional information on trace elements concentration in selected blood reference materials is given. The between-batch precision was assessed from replicate analysis (including sample preparation) of reference materials and was better than 10% RSD for 21 elements and better than 30% RSD for 36 elements under consideration. A statistical summary for results obtained for 31 blood samples from non-exposed subjects is presented. The majority of elements tested was found in the samples at concentrations higher than MDL.