CIRCULAR PAPER CHROMATOGRAPHY Part VII. A Technique for the Separation and Estimation of "Overlapping Amino Acids"

Abstract

A technique is described for the separation of amino acids which  overlap when developed with n-butanol-acetic acid-water as solvent by  circular paper chromatography employing other solvent mixtures.

The Separation of the overlapping amino acids is accomplished  by cutting out the bands relating to these amino acids which separate as  single band in n-Butanol-acetic acid-water as solvent and using the cut  strip as  'wick' for  developing another chromatogram with pyridine-  water, pyridine-amylacetate-water and pyridine-isoamylalcohol-water as  solvents.

The following groups of amino acids have been separated by using  the above solvents :—Leucine-isoleucine; Valine-methionine ; y-Amino-  butyric acid—tryptophane ; a-Aminobutyric acid—tyrosine ; f3-Alanine-  proline; Glutamic acid—threonine; Glycine—serine—aspartic acid;  Asparagine—arginine and Lysine--histidine.

The technique and apparatus used for simultaneous elution and  spotting of the amino acids contained in the cut out strip are described.  A quantitative procedure for the estimation of these amino acids  has been outlined. The method has been applied to the amino acid  analysis of casein and edestin hydrolysates.

In.principle  the  technique can also be applied to the analysis of other  substances.