HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY OF PEPTIDES ON A MICROSPHERICAL CARBON COLUMN

The properties of a microspherical carbon column for the separation of peptides and proteins are described. One hundred and thirty-three pep tides, with from 1 to 148 amino acid residues, were applied on a carbo n column and eluted with a linear gradient of acetonitrile [10-70% (v/ v), 30 min] in 0.1% (v/v) trifluoroacetic acid solution. The elution b ehaviour of the peptides on the carbon column and on an octadecylsilic a (ODS) column were compared under the same elution conditions. Relati onships between the logarithm of the hydrophobicity of peptides and th eir capacity factors were approximately linear on both columns, but so me exceptions were observed with peptides with aromatic residues, indi cating stronger adsorption on the carbon than on the ODS column. These results suggest that the major factor for the separation of peptides on both the carbon and ODS columns is hydrophobic interactions. The st ronger adsorption of aromatic side-chains in peptides on the carbon co lumn could be understood by an interaction based on the aromatic or gr aphitic nature of the surface of the microspherical carbon packings.