Two-stage ultrafiltration/diafiltration
View Patent ↗The present invention provides a method for concentrating a protein, in particular a method for concentrating a plasma product, in particular IgG, using glycine in a two-stage ultrafiltration/diafiltration approach.
1. A method for concentrating a plasma product of a solution comprising a protein, the method comprising:
a) ultrafiltering the solution using a first membrane to form a first retentate solution comprising the protein at a first concentration, wherein the first membrane has a molecular weight cutoff sufficient to retain at least a portion of the protein present in the solution;
b) diafiltering the first retentate solution with an aqueous solution using the first membrane to form a second retentate solution comprising the protein at about the first concentration;
c) formulating the second retentate solution comprising the diafiltered protein, with glycine and adjusting the pH to form a formulated second retentate solution; and
d) ultrafiltering the formulated second retentate solution of step c) using a second membrane to form a final retentate solution comprising the protein at a second concentration, wherein the second membrane has a molecular weight cutoff greater than the molecular weight cutoff of the first membrane, wherein the second concentration is greater than the first concentration.
2. The method of claim 1 , wherein the protein is IgG.
3. The method of claim 1 , wherein the first membrane is a polyethersulfone C-screen membrane having a molecular weight cutoff of 50 kDa.
4. The method of claim 1 , wherein the first concentration is about 5% protein (w/v).
5. The method of claim 1 , wherein the second membrane is a hollow fiber membrane or a cassette.
6. The method of claim 1 , wherein the second membrane has a molecular weight cutoff of 100 kDa.
7. The method of claim 1 , wherein the second concentration is at least about 19% protein (w/v).
8. The method of claim 1 , wherein the first membrane has a molecular weight cutoff sufficient to retain at least 90% of the protein present in the solution.
9. The method of claim 4 , wherein, in step c), the about 5% diafiltered protein is formulated to about 0.16 to about 0.30 M glycine and the pH is adjusted to about 4.3.
10. A method for concentrating a protein of a solution comprising the protein, the method comprising:
a) ultrafiltering the solution using a first membrane to form a first retentate solution comprising the protein at a first concentration of about 5%, wherein the first membrane has a molecular weight cutoff sufficient to retain at least about 90% of the protein;
b) diafiltering the first retentate solution using the first membrane with water to form a second retentate solution comprising the protein at about the first concentration;
c) formulating the about 5% diafiltered protein of step b) to about 0.16 to about 0.30 M glycine, wherein the formulating further comprises adjusting pH to about 4.3; and
d) ultrafiltering the second retentate solution using a second membrane to form a final retentate solution comprising the protein at a second concentration of about 19 to about 21%, wherein the second membrane has a molecular weight cutoff greater than the molecular weight cutoff of the first membrane, wherein the second concentration is greater than the first concentration.
11. The method of claim 10 , wherein the protein is IgG.
12. The method of claim 11 , wherein the first membrane has a molecular weight cutoff of about 25 kDa to about 75 kDa.
13. The method of claim 10 , wherein the first membrane has a molecular weight cutoff of about 50 kDa, wherein the second membrane has a molecular weight cutoff of about 100 kDa.
14. The method of claim 10 , wherein the second membrane is a hollow fiber membrane or a cassette.
15. A method for concentrating a plasma product of a solution comprising a protein, the method comprising:
a) ultrafiltering the solution below about 20° C. using a first membrane to form a first retentate solution comprising the protein at a first concentration, wherein the first membrane has a molecular weight cutoff sufficient to retain at least a portion of the protein present in the solution;
b) diafiltering the first retentate solution below about 20° C. with an aqueous solution using the first membrane to form a second retentate solution comprising the protein at about the first concentration;
c) formulating the second retentate solution comprising the diafiltered protein, by adding glycine and adjusting the pH to form a formulated second retentate solution; and
d) ultrafiltering the formulated second retentate solution of step c) below about 20° C. using a second membrane to form a final retentate solution comprising the protein at a second concentration, wherein the second membrane has a molecular weight cutoff greater than the molecular weight cutoff of the first membrane, wherein the second concentration is greater than the first concentration.