Alpha1-antitrypsin is a kind of plasma protein that requires a sequence of different fractionation steps to get generally. To report an effective process for isolating and purifying alpha1-antitrypsin from Cohn Fraction IV based upon a new immunoaffinity chromatography medium, named "Alpha-1 Antitrypsin Select," characterization of alpha1-antitrypsin (α1-AT) was performed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), Western blot, and tandem mass spectroscopy. Total protein content was determined by the method of Bradford under visible light absorption at 595 nm. Pretreatment process and the immunoaffinity chromatography step achieved a 60.35 ± 1.39% yield. Thus, an overall 71.68 ± 1.32 fold increase in purity and a 41.88 ± 6.98% yield were obtained from plasma. The α1-AT had a specific activity of about 1.00-1.05 PU/mg. This technique will develop an effective process for isolating and purifying, with high purity and specific activity, alpha1-antitrypsin from Cohn Fraction IV or human whole plasma, which could be an efficient and scaled-up method for alpha1-antitrypsin products purification.
Keywords: Cohn fraction IV; alpha1-antitrypsin; chromatography; mass spectrometry; purification.