Preparative countercurrent chromatography with a slowly rotating helical tube.

The capability of a simple countercurrent chromatographic scheme for obtaining high-resolution preparative-scale separations was demonstrated with the separations of a series of dinitrophenyl (DNP) amino acids and peptides. Basic studies on stationary phase retention and partition efficiency with a low-viscosity chloroform-acetic acid-0.1 N hydrochloric acid (2:2:1) phase system together with the results previously obtained with a vascous n-butanol system suggest a general applicability of low-interfacial tension phase systems by the present method.