Application of Electrophoresis on Paper to the Estimation of Alpha-, Beta-, and Gamma-Casein

Alpha-, beta-, and gamma-components of casein were separated by paper electrophoresis, and the dyed proteins in paper were estimated by direct photometry. Correction factors were determined because the components did not bind dye in proportion to their concentration. Protein concentrations corrected for differences in dye-binding capacities agreed with resuIts of protein-nitrogen analyses, and casein composition was alpha-, 60%; beta-, 32%, and gamma-, 9%.