Method and apparatus for nanoparticle transport and detection

• US 7,077,939 B1
• Filed: 06/17/2002
• Issued: 07/18/2006
• Est. Priority Date: 06/18/2001
• Status: Expired due to Fees

• Current Assignee: Texas A&M University System
• Original Assignee: Texas A&M University System
• Inventors: Sun, Li, Crooks, Richard M.
• Primary Examiner(s): NOGUEROLA, ALEXANDER STEPHAN
• Application Number:
  US10/173,905
• Time in Patent Office: 1,492 Days
• Field of Search: 422/99, 422/100, 422/50, 422/68.1, 422/82.01, 422/83, 204/450, 204/451, 204/600, 204/601, 204/409, 204/603, 204/452, 137/1, 210/500.23, 210/500.22
• US Class Current: 204/450
• CPC Class Codes: B01D 67/0062 by micromachining techniques, e.g. using masking and etching steps, photolithography
• CPC Class Codes: B01D 71/0212 Carbon nanotubes
• CPC Class Codes: B01L 2300/0896 Nanoscaled
• CPC Class Codes: B01L 2400/0487 fluid pressure, pneumatics
• CPC Class Codes: B01L 3/0241 Drop counters; Drop formers making arrays for combinatorial libraries B01J19/0046; automation of dispensing for analysis G01N35/10
• CPC Class Codes: B81B 2203/0127 Diaphragms, i.e. structures separating two media that can control the passage from one medium to another; Membranes, i.e. diaphragms with filtering function
• CPC Class Codes: B81C 1/00087 Holes
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G01N 15/13 Details pertaining to apertures
• CPC Class Codes: G01N 2015/0038 Investigating nanoparticles
• CPC Class Codes: Y10T 137/0318 Processes

Abstract

According to one embodiment an apparatus includes a membrane and at least a portion of a nanotube imbedded within the membrane. The portion of the nanotube imbedded within the membrane provides a conduit through the membrane.

Claims

1. An apparatus comprising:

a membrane;

a nanotube embedded within the membrane and providing a conduit through the membrane, the ends of the nanotube being flush with respective surfaces of the membrane; and

wherein the nanotube is a carbon nanotube.

2. A method of forming a membrane having a small hole disposed therein comprising:

surrounding at least a portion of a nanotube with a material; and

sectioning the material and the nanotube to produce the membrane having the small hole disposed therein.

3. The method of claim 2, wherein surrounding at least a portion of the nanotube with a material comprises surrounding at least a portion of the nanotube with a polymer precursor in liquid form and then solidifying the polymer.

4. The method of claim 2, wherein sectioning the material comprising slicing a thin membrane off the material with a knife.

5. The method of claim 2, and further comprising removing the nanotube from the sectioned material.

6. A method of forming a membrane having a small hole disposed therein comprising:

surrounding at least a portion of a nanotube with a liquid or gaseous material;

allowing the liquid or gaseous material to solidify around the nanotube; and

removing by chemical oxidation the at least a portion of the nanotube from the solidified material, leaving the membrane having the small hole disposed therein.

7. The method of claim 6, wherein surrounding the at least a portion of a nanotube with a liquid or gaseous material and allowing the liquid or gaseous material to solidify around the nanotube comprises depositing an inorganic solid around the nanotube.

8. The method of claim 7 wherein an inorganic solid comprises silicon nitride.

9. The method of claim 7 wherein an inorganic solid comprises silicon dioxide.

10. The method of claim 7, wherein depositing an inorganic solid comprises depositing the solid by chemical vapor deposition.

11. A method for detecting particles comprising:

providing a membrane having a portion of a nanotube disposed therein that provides a conduit through the membrane;

allowing the particles to pass through the membrane through the conduit of the nanotube;

detecting the passage of the particles through the conduit of the nanotube; and

wherein allowing the particles to pass through the membrane through the conduit of the nanotube comprises applying a pressure differential across the membrane.

12. A method for delivering a liquid material to a desired location comprising:

providing a nanotube holder between the liquid material and the desired location, the nanotube holder having a portion of a nanotube disposed therein that provides a conduit through the holder; and

forcing the liquid material through the holder to the desired location by forcing the liquid material through the conduit of the nanotube.

13. The method of claim 12, wherein forcing the liquid material comprises applying a concentration gradient across the conduit of the nanotube.

14. The method of claim 12, wherein forcing the liquid material comprises applying a pressure differential across the conduit of the nanotube.

15. The method of claim 12, wherein forcing the liquid material through the holder comprises applying an electric field across the conduit of the nanotube.

16. The method of claim 12, wherein forcing the liquid material through the holder comprises placing the nanotube holder in a centrifugal force field.

17. The method of claim 12, wherein the nanotube holder comprises a membrane.

18. The method of claim 17, wherein the membrane comprises a polymer.

19. The method of claim 17, wherein the membrane comprises an inorganic solid.

20. The method of claim 17, wherein the membrane comprises glass.

21. The method of claim 17, wherein the membrane comprises a glass reservoir.

22. The method of claim 12, wherein the liquid material comprises a plurality of microscopic particles.

23. The method of claim 12, wherein the desired location comprises a liquid medium.

24. The method of claim 12, wherein the desired location comprises a gas medium.

25. The method of claim 12, wherein the desired location comprises a vacuum of less than one atmosphere of pressure.

26. A method for delivering material to a desired location comprising:

providing a nanotube holder between the material and the desired location, the nanotube holder having a portion of a nanotube disposed therein that provides a conduit through the holder;

applying a pressure differential across the conduit of the nanotube to force the material through the holder to the desired location by forcing the material through the conduit of the nanotube; and

wherein the material comprises a liquid.