Helical wrapping of single-walled carbon nanotubes by genomic DNA

Abstract

A structure and method for forming single-stranded DNA segments/single-wall carbon nanotube complexes and a method of preparing single-stranded DNA segments. The method for forming single-stranded DNA segments/single-wall carbon nanotube complexes including: attaching single-stranded DNA segments to single-wall carbon nanotubes to form single-stranded DNA segment/single-wall carbon nanotube complexes, each of the single-stranded DNA segments having a same length of greater than 2,000 bases.

Description

BRIEF DESCRIPTION OF DRAWINGS

The features of the invention are set forth in the appended claims. The invention itself, however, will be best understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:

FIG. 1 is a schematic representation of the preparation of single-stranded DNA and single-wall CNT/single-stranded DNA complexes according to embodiments of the present invention;

FIG. 2A is a photograph of a gel electrophoresis analysis of a thiolated lambda DNA polymerase chain reaction amplification procedure before centrifuging;

FIG. 2B is photograph of a gel electrophoresis analysis of a gold/double-stranded DNA preparation procedure;

FIG. 2C is photograph of a gel electrophoresis analysis of the gold/double-stranded DNA preparation procedure after centrifuging;

FIG. 3A is a photographic comparison of single-stranded DNA-1seq mixed with single-wall carbon nanotubes and complementary single-stranded DNA-2seq mixed with SWNTs;

FIG. 3B is a photograph of a low magnification atomic force microscope scan of single-wall nanotube/single strand DNA complexes bound to mica; and

FIGS. 3C, 3D and 3E are photographs of high magnification atomic force microscope scans of single-wall nanotube/single strand DNA complexes bound to mica.

Claims

1. A method, comprising: attaching single-stranded DNA segments to single-wall carbon nanotubes to form single-stranded DNA segment/single-wall carbon nanotube complexes, each of said single-stranded DNA segments having a length of greater than 2,000 bases.

2. The method of claim 1, wherein each of said single-stranded DNA segments has a length of between about 3,000 and about 50,000 bases.

3. The method of claim 1, wherein said single-stranded DNA segments are base sequences of naturally occurring DNA molecules.

4. The method of claim 1, wherein said single-stranded DNA segments are bases sequences of bacteriophage lambda DNA.

5. The method of claim 1, wherein said single-stranded DNA segments would have lengths greater than 1 micron if they were linearly extended.

6. The method of claim 1, wherein each of said single-stranded DNA segments has an identical random base sequence.

7. The method of claim 1, wherein each of said single-stranded DNA segments has an identical base length.

8. The method of claim 1, wherein individual single-stranded DNA segments are helically wrapped around respective single-wall carbon nanotubes.

9. The method of claim 1, wherein said single-wall carbon nanotubes have a diameter of between about 0.5 nanometer and about 2.0 nanometers and have a length between about 0.7 microns and about 2.0 microns.

10. The method of claim 1, including: mixing said single-wall carbon nanotubes and said single-stranded DNA segments in water and sonicating the resultant mixture.

11. The method of claim 1, further including: binding said single-stranded DNA segment/single-wall carbon nanotube complexes to a substrate.

12. The method of claim 11, wherein said single-stranded DNA segment/single-wall carbon nanotube complexes are orientated substantially in a direction that is the same relative to a top surface of said substrate.

13. A method, comprising: replicating double-stranded DNA segments in a polymerase chain reaction in the presence of a first primer and a second primer, said second primer having a terminating thiol group attached to one end of said second primer, each replicated double-stranded DNA segment having first and second complementary strands, said second strand having a thiol group at one end of said second strand;attaching metal nanoparticles to said thiol groups of said replicated double-stranded DNA segments;breaking said replicated double-stranded DNA segments into complementary first and second single-stranded DNA segments, said second single-stranded DNA segments including said thiol groups and metal nanoparticles; andremoving said first single-stranded DNA segments from said second single-stranded DNA segments.

14. The method of claim 13, wherein said first single-stranded DNA segments have an identical length greater than 2,000 bases.

15. The method of claim 13, wherein said double-stranded DNA molecule is a naturally occurring DNA molecule.

16. The method of claim 13, wherein said double-stranded DNA has a base sequence of bacteriophage lambda DNA.

17. The method of claim 13, wherein said metal nanoparticles are phosphine-capped gold nanoparticles and said removing said first single-stranded DNA segments from said second single-stranded DNA segments includes centrifuging a suspension of said first single-stranded DNA segments and said second single-stranded DNA segments in water to form a supernatant and a sediment, wherein second single-stranded DNA segments are in said sediment and first single-stranded DNA segments are in said supernatant.

18. The method of claim, 17, further including: removing said supernatant from said sediment; andmixing single-wall carbon nanotubes with said removed supernatant to form single-stranded DNA segment/single-wall carbon nanotube complexes.

19. A structure, comprising: a single-wall carbon nanotube; anda single-stranded DNA segment helically wound around said single-wall carbon nanotube, said single-stranded DNA segment being greater than 2,000 bases in length.

20. The structure of claim 19 wherein, said single-wall carbon nanotube has a diameter of between about 0.5 nanometer and about 2.0 nanometers and a length between about 0.7 microns and about 2.0 microns; andsaid single-stranded DNA segment is a base sequence of a naturally occurring DNA molecule.