Method for purifying pharmaceutical proteins by aid of density difference processes

Abstract

The invention discloses a method for purifying pharmaceutical proteins by the aid of density difference processes. The method includes uniformly mixing to-be-purified samples with the pharmaceutical proteins, potassium dihydrogen phosphate aqueous solution and isobutanol with one another to obtain mixed liquor systems; regulating a pH (potential of hydrogen) value of the mixed liquor systems until the pH value of the mixed liquor systems is equal to 0.1+/-a pI (isoelectric point) value of the pharmaceutical proteins; pouring the mixed liquor systems with the regulated pH value into a separator, allowing the mixed liquor systems to stand still, layering the mixed liquor systems to obtain an upper layer, an intermediate layer and a lower layer and collecting the intermediate layer to obtain purified pharmaceutical proteins. The pharmaceutical proteins can be separated and purified within a few minutes and can be purified at one step by the aid of the method for purifying the pharmaceutical proteins by the aid of the density difference processes, accordingly, the time cost and the material cost can be saved, and the biological activity and the solubility of the pharmaceutical proteins can be effectively retained. The method for purifying the pharmaceutical proteins by the aid of the density difference processes has the advantages of short time consumption, small volumes, fast reaction, high efficiency, low cost, good activity and the like.

Description

technical field [0001] The invention relates to a protein purification method, in particular to a method for purifying medicinal protein by a density difference method, and belongs to the technical field of protein separation and purification. Background technique [0002] Medicinal protein bovine serum albumin (Bovine serum albumin, BSA) is a globulin in bovine serum, which contains 583 amino acid residues, of which 35 cysteines form 17 disulfide bonds. There is a free sulfhydryl group at the 34th position, the molecular weight is 66.446kDa, the isoelectric point is 4.7, the nitrogen content is 16%, the sugar content is 0.08%, only hexose and hexosamine, and the fat content is only 0.2%. Bovine serum albumin mainly plays the role of maintaining osmotic pressure, pH buffering, carrier and nutrition. In the serum-free culture of animal cells, adding albumin can play a role of physiological and mechanical protection and carrier, and has a wide range of applications in biochem...

AI Technical Summary

Problems solved by technology

Cohn fractionation process (Cohn fractionation process) and column chromatography are the most commonly used methods. Although the separation efficiency of column chromatography can reach more than 80%, the packing time of the packed column is too long. It often takes hours or even days, and requires a large amount of buffer (generally several hundred to several thousand liters), but the amount of pure product obtained by one separation is limited, resulting in low separation efficiency; expensive, relatively high cost

However, the steps of the Cohen fractionation method are cumbersome, time-consuming and labor-intensive, and the practicability is not high.