Paper Electrophoresis of Isolated Plasma Protein Fractions

Abstract

The purpose of the present investigation has been to examine in more detail a part of the basis for paper electrophoresis, namely the relationship between the amount of protein applied and the measurable color intensity. Bovine albumin and γ-globulin, as well as human albumin, α-, β- and γ-globulin were investigated by Grassmann & Hannig's (1952) method, with some modifications (Sommerfelt, to be published). The principle involved is migration on freely suspended, thin paper, staining with amido-sohwarz 10 B (Bayer) and direct photometry of the strip. 1. There is good agreement between the results with the bovine and human preparations. 2. Albumin shows the greatest stainability of the fractions investigated, 02-globulin the least. 3. During electrorphoretic migration an adsorbtion of protein to the paper takes place. 4. The amount of protein adsorbed is independent of the amount applied, i. e. the paper becomes saturated and then adsorbs no more of the same protein. 5. When the paper is saturated with albumin, only a very slight adsorption of other fractions occurs. 6. In electrophoresis of serum, the adsorbtion causes a reduction of the albumin and a slight increase of the globulin values. It thus compensates, to some extent, the greater stainability of the albumin. 7. The present investigation seems to indicate that there is a satisfactory basis for employing the described electrophoretic method in studying serum proteins, but the considerable variation of the method must be emphasized.