Isolation of cell-free nucleic acids from bodily fluid samples using solid chaotropic agents

1. A composition useful for isolating cell-free nucleic acid from a bodily fluid, comprising a chaotropic agent in solid form, a buffer, and a detergent, wherein the chaotropic agent is present in an amount of about 2 to about 10 grams and is selected such that when mixed with a volume of sample fluid to form a reaction mixture having a volume of about 2 to about 10 milliliters, the chaotropic agent is present in a concentration of about 3M to about 10M.

2. A composition according to claim 1 , wherein the buffer is solid, and the detergent is a liquid or a solid.

3. A composition according to claim 2 , wherein the buffer is a phosphate buffer salt, TrisOH/TriHCl solid, or TrisHCl/TrisHAc solid.

4. A composition according to claim 1 , wherein the buffer is liquid, and the detergent is a liquid or a solid.

5. A composition according to claim 4 , wherein the buffer is TRIS HCl, 100 mM, pH 8.0, Tris HAc, pH 8.0, or Tricine HCl, 100 mM.

6. A composition according to claim 1 , wherein the detergent is solid, and the buffer is a liquid or a solid.

7. A composition according to claim 6 , wherein the detergent is sodium deoxycholate or sodium dodecyl sulfate (SDS).

8. A composition according to claim 1 , wherein the detergent is liquid, and the buffer is a liquid or a solid.

9. A composition according to claim 8 , wherein the detergent is octylphenol ethoxylate.

10. A composition according to claim 1 , further comprising magnetic particles.

11. A composition according to claim 1 , further comprising a chelating agent or an anti-clotting agent, or a combination thereof.

12. A composition according to claim 1 , wherein the chaotropic agent is present in an amount of about 4 to about 6 grams.

13. A composition according to claim 1 , wherein the chaotropic agent is present in an amount effective to achieve a molarity of about 4M to about 6M.

14. A composition according to claim 13 , wherein the chaotropic agent is present in an amount effective to achieve a molarity of about 4M to about 7.5M.

15. A composition according to claim 1 , wherein the chaotropic agent is present in an amount effective to achieve a molarity of about 5.5M to about 6.5M.

16. A composition according to claim 1 , wherein the chaotropic agent is present in an amount effective to achieve a molarity of about 3M to about 10M.

17. A composition according to claim 1 , wherein the chaotropic agent is present in an amount effective to achieve a molarity of about 3M to about 10M.

18. A composition according to claim 1 , wherein the chaotropic agent is present in an amount effective to achieve a molarity of about 3M to about 10M.

19. A composition according to claim 1 , wherein the chaotropic agent is present in an amount effective to achieve a molarity of about 5.5M to about 6.5M.

20. A test kit for isolating cell-free nucleic acid from a bodily fluid, comprising in a first container, a chaotropic agent in solid form in an amount of about 2 to about 10 grams and is selected such that when mixed with a volume of sample fluid to form a reaction mixture having a volume of about 2 to about 10 milliliters, the chaotropic agent is present in a concentration of about 3M to about 10M, a buffer, and a detergent.

21. A test kit according to claim 20 , wherein the first container further comprises a solid phase comprising magnetic particles.

22. A test kit according to claim 20 , further comprising a second container having disposed therein a solid phase comprising magnetic particles.

23. A test kit according to claim 22 , wherein the magnetic particles are coated with silica.

24. A test kit according to claim 20 , further comprising a second container having disposed therein a washing buffer comprising a chaotrope.

25. A test kit according to claim 20 , further comprising a third container comprising a washing buffer comprising a drying agent.

26. A test kit according to claim 20 , further comprising a fourth container comprising an elution buffer.

27. A process for isolating cell-free nucleic acid or an analog thereof from a bodily fluid, comprising: a) mixing in a container the bodily fluid, a chaotropic agent in solid form, a detergent and a buffer, and a solid phase which comprises magnetic particles, thus forming a reaction mixture containing the cell-free nucleic acid, wherein the chaotropic agent is present in the reaction mixture in an amount of about 2 to about 10 grams and at a concentration of about 3M to about 10M based on a volume of reaction mixture of about 2 ml to about 10 ml; b) magnetically separating the solid phase having the cell-free nucleic acid bound thereto from the reaction mixture; and optionally c) dissociating the nucleic acid from the solid phase.

28. A process according to claim 27 , wherein the bodily fluid comprises blood or a component thereof.

29. A process according to claim 28 , wherein the bodily fluid is maternal blood or a component thereof.

30. A process according to claim 27 , wherein the bodily fluid is obtained from a cancer patient who has been treated with a therapeutic agent which comprises a nucleic-acid analog.

31. A process according to claim 27 , wherein the reaction mixture has a volume of about 2 ml to about 10 ml.

32. A process according to claim 27 , wherein the blood component is plasma.

33. A process according to claim 27 , wherein the blood component is serum.

34. A process according to claim 27 , wherein the bodily fluid comprises urine.

35. A process according to claim 27 , wherein the detergent is in solid form.

36. A process according to claim 27 , wherein the buffer is in solid form.

37. A process according to claim 27 , wherein the detergent and the buffer are in solid form.