Abstract
Microwave-induced plasma mass spectrometry (MIP-MS) was used to determine the selenium concentrations in human blood plasma. Blood plasma from volunteers, the standard reference materials of human blood serum and bovine serum, were used to investigate the suitability of the digestion method and the matrix effects due to coexisting elements, and to confirm the accuracy of the obtained values. Two sample-preparation procedures, microwave digestion and simple dilution with 0.1% Triton X-100 solution, were examined. In the latter method, oxygen gas was mixed into plasma nitrogen gas at a gas flow of 30 ml/min to prevent any instability of the measurement caused by carbide formed from organic components. The selenium concentrations were calculated from the ion counts at m/z=80 using a calibration curve with an internal standard correction. Both sample-preparation procedures were suitable for human blood plasma. The concentrations of several other elements, such as magnesium, iron, copper, zinc, and rubidium in blood plasma and in serum sam-ples, could be measured simultaneously with selenium, indicating that MIP-MS was useful for a simple and rapid determination of elements in blood plasma.
