Method, use and kit for separating albumin from contaminants in a liquid
The present invention is a method of separating recombinant human serum albumin (rHSA) from low molecular weight contaminants in a liquid, which method comprises the steps of: (a) providing a separation medium, which includes anion-exchanging ligands coupled to a base matrix; and (b) contacting the liquid with the separation medium to adsorb the rHSA to the ligands. In one embodiment, the functional groups of the ligands are weak anion-exchanging groups, preferably secondary amines, and the density of ligands on the base matrix is relatively high.
1. A method of separating recombinant human serum albumin (rHSA) from low molecular weight rHSA degradation products in a liquid, which method comprises the step of
(a) providing a weak anion-exchange separation medium on a base matrix suitable for separating rHSA from said low molecular weight rHSA degradation products;
(b) contacting the liquid containing said rHSA and low molecular weight rHSA degradation products with the separation medium under conditions that allow the rHSA to adsorb and the degradation products to wash through; and
(c) eluting said rHSA from the separation medium using a salt gradient that releases said rHSA from the ligands.
2. The method of claim 1 , wherein the weak anion-exchange separation medium has ligands with the formula:
—O—CH 2 —CH(OH)—CH 2 —O—CH 2 —CH (OH)—CH 2 —N—(CH 2 ) n
where n is an integer of 1-8.
3. The method of claim 1 , wherein the weak anion-exchange separation medium has a ligand concentration of at least about 50 μmol/ml medium.
4. The method of claim 1 , wherein the base matrix includes porous, essentially spherical polysaccharide particles.
5. The method of claim 1 , wherein the low molecular weight degradation products are of a molecular weight below 67 kDa.
6. The method of claim 1 , further comprising an additional step of washing the separation medium with a buffer between steps (b) and (c).
7. The method of claim 1 , wherein the liquid is a culture broth.