ISOLATION AND PURIFICATION OF THE CLEARING FACTOR OF POSTHEPARIN HUMAN PLASMA.

Abstract A method for the isolation and purification of the clearing factor of postheparin human plasma has been developed. The essential steps in the purification procedure include: elimination of fibrinogen from the original postheparin plasma by treatment with bentonite; adsorption of the clearing factor with tricalcium phosphate, 0.4 Gm. per 100 ml. plasma; elution of the factor with sodium citrate, 0.18 M; and fractionation of the eluate with ethanol. This purified material retains most of the clearing activity of the original one, present in the postheparin plasma, and on the basis of protein contained in the final product, compared to the amount of protein contained in the plasma, shows a purification approximately one thousand eight hundred fold. This purified clearing factor preparation migrated during ultracentrifugation as a single peak.