Isolation of alpha-1-antitrypsin from human plasma by partitioning in aqueous biphasic systems of polyethyleneglycol-phosphate.
The partitioning of alpha-1-antitrypsin was assayed in biphasic aqueous systems containing potassium phosphate and two polyethyleneglycols of molecular mass 600 and 1000, respectively. In order to isolate the alpha-1-antitrypsin from serum plasma, the partitioning behaviour of human serum albumin, its principal contaminant, was also studied. Several aqueous two-phase systems with different partitioning properties were obtained by varying the PEG1000/PEG600 mass proportion. In systems with PEG1000/PEG600 mass ratio of 8, the optimal difference between the partition coefficients of both proteins was found. Under such conditions, a satisfactory purification was carried out by a three-step extraction procedure. By applying this method the alpha-1-antitrypsin specific activity increased severalfold (nearly 10 times) with a yield of 43%.
Reh
Georgina
G
Physical Chemistry Department and CONICET, Faculty of Biochemistry and Pharmaceutical Sciences, National University of Rosario, Suipacha 570, Rosario 2000, Argentina.
Nerli
Bibiana
B
Picó
Guillermo
G
D006801:Humans; D008970:Molecular Weight; D011092:Polyethylene Glycols / Q000737:chemistry*; D000515:alpha 1-Antitrypsin / Q000302:isolation & purification*
D000515:alpha 1-Antitrypsin; D011092:Polyethylene Glycols