Nucleic acid functionalized nonoparticles for therapeutic applications

1. A method of inhibiting expression of a gene product comprising the step of hybridizing a polynucleotide encoding said gene product with one or more oligonucleotides complementary to all or a portion of said polynucleotide, said oligonucleotide being covalently bound to a nanoparticle that is from about 5 nanometers (nm) to about 50 nm in mean diameter, wherein the oligonucleotide comprises a spacer that creates a distance between the oligonucleotide and the nanoparticle that is equivalent to at least 10 nucleotides,

wherein said nanoparticle has an in vitro property of inhibiting expression of said gene product by at least 5% compared to expression in the absence of the oligonucleotide and in the absence of a transfection agent,

and wherein hybridization of the polynucleotide encoding said gene product and said oligonucleotide results in inhibiting expression of said gene product.

2. The method of claim 1 wherein expression of said gene product is inhibited in vivo.

3. The method of claim 1 wherein expression of said gene product is inhibited in vitro.

4. The method of claim 1 wherein said nanoparticle is metallic.

5. The method of claim 1 wherein said nanoparticle is organic.

6. The method of claim 4 wherein said nanoparticle is selected from the group consisting of a gold nanoparticle, a silver nanoparticle, a platinum nanoparticle, an aluminum nanoparticle, a palladium nanoparticle, a copper nanoparticle, a cobalt nanoparticle, an indium nanoparticle, and a nickel nanoparticle.

7. The method of claim 1 wherein said oligonucleotide is bound to said nanoparticle through one or more sulfur linkages.

8. The method of claim 1 wherein said oligonucleotide is about 5 to about 100 nucleotides in length, about 5 to about 90 nucleotides in length, about 5 to about 80 nucleotides in length, about 5 to about 70 nucleotides in length, about 5 to about 60 nucleotides in length, about 5 to about 50 nucleotides in length, about 5 to about 45 nucleotides in length, about 5 to about 40 nucleotides in length, about 5 to about 35 nucleotides in length, about 5 to about 30 nucleotides in length, about 5 to about 25 nucleotides in length, about 5 to about 20 nucleotides in length, about 5 to about 15 nucleotides in length, or about 5 to about 10 nucleotides in length.

9. The method of claim 1 wherein said oligonucleotide is a DNA oligonucleotide.

10. The method of claim 1 wherein said oligonucleotide is an RNA oligonucleotide.

11. The method of claim 1 wherein said oligonucleotide includes at least one modified internucleotide linkage.

12. The method of claim 11 wherein said oligonucleotide is a peptide nucleic acid.

13. The method of claim 1 wherein said oligonucleotide includes at least one modified nucleic acid sugar moiety.

14. The method of claim 1 wherein said oligonucleotide includes at least one modified nucleic acid.

15. The method of claim 1 wherein said spacer is an organic moiety.

16. The method of claim 15 wherein said organic moiety is a polymer.

17. The method of claim 16 wherein said polymer is a water-soluble polymer.

18. The method of claim 16 wherein said polymer is a nucleic acid.

19. The method of claim 16 wherein said polymer is a polypeptide.

20. The method of claim 16 wherein said polymer is an oligosaccharide.

21. The method of claim 1 wherein said nanoparticle further comprises a targeting molecule.

22. The method of claim 1 wherein said oligonucleotide is an inhibitory RNA that performs a regulatory function.

23. The method of claim 22 wherein the inhibitory RNA is selected from the group consisting of a small inhibitory RNA (siRNA), an RNA that forms a triplex with double stranded DNA, and a ribozyme.

24. The method of claim 1 wherein said oligonucleotide is 100% complementary to said polynucleotide.

25. The method of claim 1 wherein said oligonucleotide is greater than 95% complementary to said polynucleotide.

26. The method of claim 1 wherein said oligonucleotide is greater than 90% complementary to said polynucleotide.

27. The method of claim 1 wherein said oligonucleotide is greater than 80% complementary to said polynucleotide.

28. The method of claim 1 wherein said nanoparticle is bound to at least two oligonucleotides having different sequences.

29. The method of claim 28 wherein said different sequences hybridize to different regions on the same polynucleotide.

30. The method of claim 28 wherein said different sequences hybridize to different polynucleotides.

31. The method of claim 1 wherein said polynucleotide is a bacterial polynucleotide.

32. The method of claim 1 wherein said polynucleotide is a viral polynucleotide.

33. The method of claim 1 wherein expression of said gene product is inhibited by at least 10%.

34. The method of claim 1 wherein said oligonucleotide is bound to said nanoparticle at a surface density of at least 10 pmol/cm 2 .

35. The method of claim 1 wherein expression of said gene product is associated with a disease state.

36. The method of claim 1 wherein said polynucleotide is a mitochondrial polynucleotide.

37. The method of claim 1 wherein the oligonucleotide is released from the nanoparticle after the nanoparticle enters a cell.

38. The method of claim 1 wherein said oligonucleotide is 100% complementary to said polynucleotide.

39. The method of claim 1 wherein said oligonucleotide is greater than 75% complementary to said polynucleotide, greater than 70% complementary to said polynucleotide, greater than 65% complementary to said polynucleotide, greater than 60% complementary to said polynucleotide, greater than 55% complementary to said polynucleotide, or greater than 50% complementary to said polynucleotide.

40. The method of claim 11 wherein the modified internucleoside linkage is selected from the group consisting of a phosphorothioate linkage, a morpholino linkage, a methylphosphonate linkage, or a sulfonyl linkage.

41. The method of claim 1 wherein said oligonucleotide is bound to said nanoparticle through a 5′ linkage.

42. The method of claim 1 wherein said oligonucleotide is bound to said nanoparticle through a 3′ linkage.

43. The method of claim 1 wherein said polynucleotide is a mRNA encoding said gene product and translation of said gene product is inhibited.

44. The method of claim 1 wherein said polynucleotide is DNA in a gene encoding said gene product and transcription of said gene product is inhibited.

45. The method of claim 44 wherein said DNA encodes said gene product.

46. The method of claim 44 wherein said DNA is complementary to a coding region for said gene product.

47. The method of claim 1 wherein expression of said gene product is inhibited by at least 5%, at least 15%, at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100%.

48. The method of claim 1 wherein said oligonucleotide is bound to said nanoparticle at a surface density of at least 15 pmol/cm 2 , at least 20 pmol/cm 2 , at least 10 pmol/cm 2 , at least 25 pmol/cm 2 , at least 30 pmol/cm 2 , at least 35 pmol/cm 2 , at least 40 pmol/cm 2 , at least 45 pmol/cm 2 , or at least 50 pmol/cm 2 .

49. The method of claim 23 wherein the siRNA comprises a sense strand polynucleotide hybridized to a complementary antisense strand polynucleotide.