The Zinc Content of Normal Human Whole Blood,

The literature contains few references to the quantitative determination of zinc in human blood. It is difficult to compare the scant data which are available because of the divergence of the methods used and of the units in which different authors chose to express their results (l-5). It became apparent in the pursuit of our work on zinc in leucocytes and red blood cells, preliminary reports of which have appeared elsewhere (6-8), that the data available in the literature did not offer an adequate point of reference for our studies. A technique was developed (9) for the microanalysis of zinc in biologic materials. This method is sensitive for quantities as small as 1 y (microgram) and its limits of precision are defined by a standard deviation of flO.O per cent. This technique was employed throughout our work. Arc spectrography’ of leucocytes and erythrocytes had demonstrated that, for equal numbers of cells, zinc was present in higher concentration in leucocytes than in erythrocytes. We therefore decided to examine whole blood, plasma, washed erythrocytes, and washed leucocytes separately for their zinc content.