Ion exchange chromatography of proteins and peptides

1. A method for purifying a peptide from a mixture comprising said peptide and related impurities, said method comprising:

a) eluting said related impurities of said mixture from an anion exchange chromatography matrix using a solution comprising an organic modifier, water, a buffer, and optionally a salt component at a linear or step gradient or isocratically in salt component, and at pH-values maintained with a buffer so that said peptide has a negative local or overall net charge and said related impurities have a local or overall negative net charge which is lower than the negative net charge of said peptide so as to remove said related impurities; and without an intervening step,

b) subsequently, eluting said peptide in the absence of an organic modifier, by a step or linear change to an aqueous solvent optionally with a salt component, at the same or lower pH-values maintained with a buffer.

2. The method according to claim 1 further comprising subjecting the peptide eluted in step (b) to analytical tests and/or further purification.

3. The method of claim 1 , wherein said peptide to be purified is selected from polypeptides, oligopeptides, proteins, and receptors.

4. The method of claim 1 , wherein said peptide to be purified is selected from glucagon, hGH, insulin, FactorVII, FactorVIIa, FactorVIIai, FFR-FactorVIIa, glucagon-like peptide-1, glucagon-like peptide-2 and analogs thereof.

5. The method of claim 1 , wherein the ratio of organic modifier to water on a weight percent basis is from 1:99 to 99:1.

6. The method of claim 1 , wherein the organic modifier is selected from C 1-6 alkanol, C 1-6 alkenol, C 1-6 -alkynol, urea, guanidine, C 1-6 -alkanoic acid, C 2-6 -glycol, or C 3-7 -polyalcohol.

7. The method according to claim 1 , wherein the peptide is selected from the group consisting of Val 8 GLP-1(7-37), Thr 8 GLP-1(7-37), Met 8 GLP-1(7-37), Gly 8 GLP-1(7-37), Val 8 GLP-1(7-36) amide, Thr 8 GLP-1(7-36) amide, Met 8 GLP-1(7-36) amide, Gly 8 GLP-1(7-36) amide, Arg 34 GLP-1(7-37, and B28IsoAsp insulin.

8. An industrial method for producing a pure peptide from a mixture comprising said peptide and related impurities, said method comprising:

a) eluting said related impurities of said mixture from an anion exchange chromatography matrix using a solution comprising an organic modifier, water, a buffer, and optionally a salt component at a linear or step gradient or isocratically in salt component, and at pH-values maintained with a buffer so that said peptide has a negative local or overall net charge and said related impurities have a local or overall negative net charge which is lower than the negative net charge of said peptide so as to remove said related impurities; and without an intervening step,

b) subsequently, eluting said peptide in the absence of an organic modifier, by a step or linear change to an aqueous solvent optionally with a salt component, at the same or lower pH-values maintained with a buffer.

9. The method according to claim 8 further comprising subjecting the peptide eluted in step (b) to analytical tests and/or further purification.

10. The method according to claim 8 , wherein said peptide to be purified is selected from polypeptides, oligopeptides, proteins, and receptors.

11. The method according to claim 8 , wherein said peptide to be purified is selected from glucagon, hGH, insulin, FactorVII, FactorVIIa, FactorVIIai, FFR-FactorVIIa, glucagon-like peptide-1, glucagon-like peptide-2 and analogs thereof.

12. The method according to claim 8 , wherein the ratio of organic modifier to water on a weight percent basis is from 1:99 to 99:1.

13. The method according to claim 8 , wherein the organic modifier is selected from C 1-6 alkanol, C 1-6 alkenol, C 1-6 alkynol, urea, guanidine, C 1-6 -alkanoic acid, C 2-6 -glycol, or C 3-7 -polyalcohol.

14. A method for purifying a peptide selected from glucagon, hGH, insulin, FactorVII, FactorVIIa, FactorVIIai, FFR-FactorVIIa, glucagon-like peptide-1, and glucagon-like peptide-2 and analogs thereof from a mixture comprising said peptide and related impurities, said method comprising:

a) eluting said related impurities of said mixture from an anion exchange chromatography matrix using a solution comprising an organic modifier, water, a buffer, and optionally a salt component at a linear or step gradient or isocratically in salt component, and at pH-values maintained with a buffer so that said peptide has a negative local or overall net charge and said related impurities have a local or overall negative net charge which is lower than the negative net charge of said peptide so as to remove said related impurities; and

b) subsequently, eluting said peptide in the absence of an organic modifier, by a step or linear change to an aqueous solvent optionally with a salt component, at the same or lower pH-values maintained with a buffer.

15. The method according to claim 14 , wherein said peptide is glucagon-like peptide-1 or an analog thereof.

16. The method according to claim 15 , wherein said glucagon-like peptide-1 analog is selected from the group consisting of Val 8 GLP-1(7-37), Thr 8 GLP-1(7-37), Met 8 GLP-1(7-37), Gly 8 GLP-1(7-37), Val 8 GLP-1(7-36) amide, Thr 8 GLP-1(7-36) amide, Met 8 GLP-1(7-36) amide, Gly 8 GLP-1(7-36) amide and Arg 34 GLP-1(7-37).

17. The method according to claim 14 , wherein said peptide is insulin or an analog thereof.

18. The method according to claim 17 , wherein said insulin analog is B28IsoAsp insulin.

19. The method according to claim 14 , wherein the solution used to elute related impurities from the anion exchange chromatography matrix in step (a) includes a salt component.

20. The method according to claim 19 , wherein the related impurities are eluted from the anion exchange chromatography matrix in step (a) with a linear gradient in the salt component.

21. The method according to claim 19 , wherein the organic modifier in the solution used to elute related impurities from the anion exchange chromatography matrix in step (a) is a C 1 –C 6 alkanol.