Direct multielemental analysis of human serum by ICP-MS with on-line standard addition using flow injection

Abstract
A simple method where on-line standard addition is performed using flow injection was applied to the direct analysis of human serum by inductively coupled plasma mass spectrometry (ICP-MS). The method involves the injection of 50 μL aliquots of sample into two carriers: 1% HNO3 and a standard solution in 1% HNO3 whose analyte concentration is greater than that in the sample. Because flow injection is used, no sample pretreatment (such as sample dilution or the addition of surfactant or internal standard) is needed, which minimizes sample contamination. Seronorm reference human serum was analyzed. Results in good agreement with the certified values were obtained for Al, Mn, Fe, Co, Cu and Zn.