METHODS OF THE PROTEINS DOWNSTREAM PURIFICATION EFFICIENCY INCREASING WITH THE USE OF MEMBRANE ION EXCHANGE CHROMATOGRAPHY Russian patent published in 2018 - IPC C07K1/18 

FIELD: technological processes; chemistry.

SUBSTANCE: invention relates to the downstream antibodies purifying chromatography steps efficiency enhancing method, comprising: a) passing a composition comprising an antibody of interest and a contaminating ionic polymer through an ion-exchange membrane, characterized by that the antibody and membrane have an opposite charge, under operating conditions, which consist of a buffer having a pH sufficiently different from the antibody pI to increase the antibody charge, and a low ionic strength effective to prevent buffer ion charges shielding, which cause the membrane to bind the antibody and at least one contaminating ionic polymer; b) ion exchange membrane reloading to a loading density of 1,000–5,000 g/L in such a way, that at least one of said contaminating ionic polymer remains bound to the membrane, whereas the antibody of interest is mainly in the eluate; c) trapping the eluate from the ion exchange membrane, which contains the antibody of interest; d) ion exchange chromatography step, which has a charge similar to the previous membrane, to which the membrane eluate containing the antibody of interest is subjected, and e) recovering the purified antibody from the ion exchange chromatography eluate.

EFFECT: method makes it possible to improve the proteins purification and to remove the ionic polymer impurities, for example, such as polyethyleneimine.

27 cl, 16 dwg, 2 tbl, 1 ex