The second prototype of the cross axis synchronous flow through coil planet centrifuge with a 20 cm revolutional radius was constructed to study its capability of performing preparative countercurrent chromatography. A series of preliminary studies on retention of stationary phase and partition efficiency was conducted with a short coil prepared from 0.26 cm I.D. PTFE (polytetrafluoroethylene) tubing. The results indicated that 1) the present system provides satisfactory retention of the stationary phase for various two phase solvent systems with a broad spectrum in hydrophobicity, 2) the lateral coil position on the column holder produces substantially higher retention of the stationary phase than the central coil position, if the proper mode of planetary motion is chosen, and 3) partition efficiencies of test samples expressed in terms of peak resolution were closely correlated with the retention of the stationary phase (correlation coefficient = + 0.8). Using a pair of large multilayer coil columns connected in series with a total capacity of 1600 ml, preparative capability of the present countercurrent chromatographic method was successfully demonstrated on separation of various samples including dinitrophenyl amino acids, dipeptides, indole auxins, flavonoids (from a crude extract of sea buckthorn), and steroids (from a crude reaction mixture).
