COUNTERCURRENT CHROMATOGRAPHIC-SEPARATION OF PROTEINS BY CROSS-AXIS COIL PLANET CENTRIFUGE - CHOICE OF POLYMER PHASE SYSTEMS AND REVOLUTIONSPEED

Countercurrent chromatographic separation of proteins by the cross-axi s coil planet centrifuge was maximized by selecting the suitable polym er phase system and revolution speed. Polymer phase systems composed o f polyethylene glycol (PEG) 1000 and several inorganic salts were exam ined to determine partition coefficient values (K) for various protein s. The overall results indicated that the polymer phase system compose d of 12.5% (w/w) PEG 1000 and 12.5% (w/w) dibasic potassium phosphate yielded suitable K values for most proteins except for cytochrome C an d apo-transferrin which may be separable with a solvent system compose d of 12.5% (w/w) PEG 1000 and 24% (w/w) potassium citrate. A series of experiments with the PEG 1000 potassium phosphate system under variou s revolution speeds revealed that the best separation was achieved at 850 rpm. The above optimized conditions may be applied to separations of other protein samples.