Tunable elastomeric nanochannels for nanofluidic manipulation

1. A microfluidic system, comprising:

a) a substrate comprising at least one inlet and at least one outlet formed in said substrate, wherein said inlet and outlet are in fluid communication with one or more closed elastomeric nanochannels that span the distance between said inlet and said outlet and are in fluid communication with both of said inlet and said outlet, wherein said nanochannels are tunneling cracks formed in said substrate by stretching a substrate between said inlet and outlet, and wherein said elastomeric nanochannels are open to said inlet and said outlet when stretched and closed to said inlet and said outlet when relaxed; and

b) a component configured to exert strain on said nanochannels to stretch said nanochannels.

2. The system of claims 1 , wherein said inlet and said outlet are microchannels.

3. The system of claim 1 , wherein said substrate is comprised of one or more pieces of a stiff thin film sandwiched by one or more compliant materials.

4. The system of claim 3 , wherein said stiff film is oxidized polydimethylsiloxane (PDMS).

5. The system of claim 3 , wherein said compliant material is unoxidized bulk PDMS.

6. The system of claim 3 , wherein said stiff film is a metal.

7. The system of claim 6 , wherein said metal is gold.

8. The system of claim 1 , wherein said one or more nanochannels intersect each other.

9. The system of claim 1 , wherein said one or more nanochannels originate from different inlets or outlets.

10. The system of claim 1 , further comprising a transport component configured to transport molecules through said nanochannels.

11. The system of claim 10 , wherein said transport component generates an electric field.

12. The system of claim 1 , wherein said system further comprises a biological molecule contained in said nanochannels.

13. The system of claim 12 , wherein said biological molecule is selected from the group consisting of a nucleic acid and protein.

14. A cell growth system, comprising:

a) a substrate comprising at least one inlet and at least one outlet formed in said substrate, wherein said inlet and outlet are in fluid communication with one or more closed elastomeric nanochannels that span the distance between said inlet and said outlet and are in fluid communication with both of said inlet and said outlet, wherein said nanochannels are tunneling cracks formed in said substrate by stretching a substrate between said inlet and said outlet, and wherein said elastomeric nanochannels are open to said inlet and said outlet when stretched and closed to said inlet and said outlet when relaxed;

b) a component configured to exert strain on said nanochannels to stretch said nanochannels such that the cross section of said nanochannels are altered when stretched; and

c) a plurality of cells or cellular portions contained within said nanochannels.

15. A method, comprising:

a) contacting a biological molecule, nanoparticle, or cell with a system comprising i) a substrate comprising at least one inlet and at least one outlet formed in said substrate, wherein said inlet and outlet are in fluid communication with one or more closed elastomeric nanochannels that span the distance between said inlet and said outlet and are in fluid communication with both of said inlet and said outlet, wherein said nanochannels are tunneling cracks formed in said substrate by stretching a substrate between said inlet and said outlet, and wherein said elastomeric nanochannels are open to said inlet and said outlet when stretched and closed to said inlet and said outlet when relaxed; and ii) a component configured to exert strain on said nanochannels to stretch said nanochannels such that the cross section of said nanochannels are altered when stretched; and

b) performing a biological assay on said biological molecule, nanoparticle, or cell.

16. The method of claim 15 , further comprising the step of moving said biological molecule, nanoparticle, or cell into or through said nanochannels using a transport component.

17. The method of claim 16 , wherein said transport component generates an electric field.

18. The method of claim 15 , further comprising the step of exerting strain on said nanochannels under conditions such that the cross section of said nanochannels is altered.

19. The method of claim 15 , wherein the cross section of said nanochannels is altered such that smaller molecules move through the channels and larger molecules are excluded from nanochannels or not allowed to move through nanochannels.

20. The method of claim 15 , wherein said biological molecule is selected from the group consisting of a nucleic acid and a protein.

21. The method of claim 15 , wherein said biological assay is selected from the group consisting of a nucleic acid stretching assay, a nucleic acid sequencing assay, and an assay for determining cell growth or viability.