Purification of protein C from human plasma by precipitation and aqueous two-phase partitioning

Summary Precipitation with PEG and partitioning in PEG/dextran aqueous two-phase systems are applied to the purification of protein C, a human plasma protein with a key role in anti-coagulation. Tandem application of precipitation followed by partitioning yields a purification factor for protein C greater than that using either process individually. The results are discussed using the hypothesis that the mechanism of solvation of protein C by PEG is similar, while that for total plasma proteins is different, in the two processes.