A screening method for protein characterization and differentiation.

A circular paper chromatographic method was developed for the separation of the amino acids in proteins into 7 subgroups. Butanol-acetic acid water (4+1+1) was used as the developing solvent. Eluted ninhydrin-stained aminograms gave rise to graphic profiles or numerical indexes based on absorbance percentages. The profiles can be used to compare protein-containing samples. Twenty different samples were studied through 190 comparisons of graphic profiles and coefficients of correlation, with only 4% misleading results. The method showed excellent reproducibility for the identification or differentiation of proteins and has the advantage of being performed with low-priced apparatus and reagents.