Isolation of corpuscular components of whole blood for the determination of selenium in blood cells.

Currently, the determination of trace elements in plasma or whole blood for the evaluation of adequate supply is unsatisfactory as it does not reflect exactly the biochemical processes in the human organism. A method of isolating cell fractions was developed in order to be able to analyze these elements in the corpuscular components of the blood. The separation, which is simple to perform, makes possible a high yield of erythrocytes, thrombocytes, and polymorphnuclear and mononuclear leucocytes, as well as a high purity of the cell fractions. For the first time a precise determination of trace elements in leucocytes has become possible. The concentration in erythrocytes was not calculated but measured directly, avoiding the danger of a compounding of errors by the combination of many steps. The highest relative selenium content of an investigated reference group (n = 25) was found in the erythrocytes (39.7%), followed by the plasma (29.9%) and the thrombocytes (24.9%). The leucocytes had the lowest concentration with < 1.9% in the polymorphonuclear and < 3.7% in the mononuclear cells. A comparison of these results with the distribution of selenium in the blood compartments will show whether the use of erythrocytes resp. thrombocytes for the analysis of this element is of greater value for diagnosis and therapy than currently employed procedures.