Role of matrix effect in analyses of biological objects the mass spectrometer with inductively coupled plasma

An attempt at eliminating the nonspectral matrix effect leading to suppression of the analytic signal intensity at instrument output has been made using an Agilent-7700 mass spectrometer with inductively coupled plasma with a quadrupole analyzer for several elements in blood and urine. It is shown that acid and salt compositions, as well as organic substances in the composition of the sample itself, play a decisive role in the emergence of the nonspectral matrix effect. The role of acid, salt, and organic compositions of the entire blood matrix and urine in underrating the results of determination of several elements has been estimated. It has also been shown that the internal standard must be chosen proceeding from the closeness of its first ionization potential to the first ionization potential of the element being determined. The contributions of nonspectral matrix effects to the distortion of the results of analysis of biological liquids have been analyzed and estimated. It has been found that the dependence of the matrix effect on salts in the acidic matrix and on the operating regime of the instrument is additive.