Nitrocellulose filtration to remove proteins from polynucleotides

• US 5,004,806 A
• Filed: 10/17/1988
• Issued: 04/02/1991
• Est. Priority Date: 10/17/1988
• Status: Expired due to Fees

• Current Assignee: Molecular Devices
• Original Assignee: Molecular Devices
• Inventors: Kung, Viola T.
• Primary Examiner(s): Moskowitz, Margaret
• Assistant Examiner(s): Furman, Keith C.
• Application Number:
  US07/258,895
• Time in Patent Office: 897 Days
• Field of Search: 530/412, 530/414, 530/415, 530/417, 530/422, 935/19, 536/27
• US Class Current: 530/415
• CPC Class Codes: C07K 1/34 by filtration, ultrafiltration or reverse osmosis
• CPC Class Codes: C12N 15/1017 by filtration, e.g. using filters, frits, membranes

Abstract

The present invention encompasses a method for removing proteins from a solution containing polynucleotides and proteins comprising filtering the solution through a nitrocellulose membrane at neutral or basic pH.

Claims

1. A method for quantitatively removing microgram quantities of proteins from a solution containing picogram quantities of polydeoxyribonucleotides having at least about 300 nucleotides per strand and microgram quantities of proteins comprising filtering the solution through a nitrocellulose membrane at neutral or basic pH.

2. A method according to claim 1, wherein the pH of the solution containing polydeoxyribonucleotides and proteins is adjusted to about 7 to 12.

3. A method according to claim 2, wherein the polydeoxyribonucleotides are double-stranded DNA.

4. A method according to claim 1, wherein the pH of the solution containing polydeoxyribonucleotides and proteins is adjusted to about 11 to 12.

5. A method according to claim 4, wherein the polydeoxyribonucleotides are single-stranded DNA molecules.

6. A method according to claim 4, wherein the proteins are DNA-binding proteins.

7. In a method for removing microgram quantities of protein from a solution containing microgram quantities of protein and picogram quantities of polydeoxyribonucleotides having at least about 300 nucleotides per strand wherein the solution is filtered through a membrane or gel filtration media, the improvement comprising filtering the solution through a nitrocellulose membrane at neutral or basic pH.

8. A method according to claim 7, wherein the pH of the solution is adjusted to about 7 to 12.

9. A method according to claim 8, wherein the polydeoxyribonucleotides are double-stranded DNA.

10. A method according to claim 8, wherein the pH of the solution is adjusted to about 11 to 12.

11. A method according to claim 10, wherein the polydeoxyribonucleotides are single-stranded DNA molecules.

12. A method according to claim 11, wherein the proteins are DNA-binding proteins.

13. A method for quantitatively removing microgram quantities of proteins from a solution containing picogram quantities of polydeoxyribonucleotides having at least about 300 nucleotides per strand and microgram quantities of proteins comprising the steps of:

(a) filtering the solution through a nitrocellulose membrane at neutral or basic pH; and

(b) filtering the solution through a membrane or gel filtration media.

14. A method according to claim 13, comprising the additional step of digesting remaining protein with a protease.

15. A method according to claim 13, comprising the additional step of extracting remaining protein with phenol.

16. A method according to claim 13, comprising the additional steps of:

(c) extracting remaining protein with phenol; and

(d) digesting remaining protein with a protease.

17. A method for quantitatively removing microgram quantities of proteins from a solution containing picogram quantities of polydeoxyribonucleotides having at least about 300 nucleotides per strand and microgram quantities of proteins comprising the steps of:

(a) filtering the solution through a membrane or gel filtration media; and

(b) filtering the solution through a nitrocellulose membrane at neutral or basic pH.

18. A method according to claim 17, comprising the additional step of digesting remaining protein with a protease.

19. A method according to claim 17, comprising the additional step of extracting remaining protein with phenol.

20. A method according to claim 17, comprising the additional steps of:

(c) extracting remaining protein with phenol; and

(d) digesting remaining protein with a protease.