Droplet transportation devices and methods having a fluid surface

• US 7,547,380 B2
• Filed: 01/12/2004
• Issued: 06/16/2009
• Est. Priority Date: 01/13/2003
• Status: Expired due to Fees

• Current Assignee: North Carolina State University (University of North Carolina System)
• Original Assignee: North Carolina State University (University of North Carolina System)
• Inventors: Velev, Orlin
• Primary Examiner(s): Olsen; Kaj K
• Application Number:
  US10/755,843
• Publication Number:
  US 20040211659A1
• Time in Patent Office: 1,982 Days
• Field of Search: 204/547, 204/643, 204/554, 204/660, 204/164
• US Class Current: 204/547
• CPC Class Codes: B01F 33/3021 the components to be mixed being combined in a single independent droplet, e.g. these droplets being divided by a non-miscible fluid or consisting of independent droplets
• CPC Class Codes: B01F 33/3031 using electro-hydrodynamic [EHD] or electro-kinetic [EKI] phenomena to mix or move the fluids
• CPC Class Codes: B01J 19/0093 Microreactors, e.g. miniaturised or microfabricated reactors laboratory containers with capillary fluid transport in microfabricated channels or chambers B01L3/5027
• CPC Class Codes: B01J 2219/00783 Laminate assemblies, i.e. the reactor comprising a stack of plates
• CPC Class Codes: B01J 2219/00853 Employing electrode arrangements
• CPC Class Codes: B01J 2219/0086 Dimensions of the flow channels
• CPC Class Codes: B01J 2219/00889 Mixing micromixers B01F33/30
• CPC Class Codes: B01J 2219/00891 Feeding or evacuation
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2300/0819 Microarrays; Biochips
• CPC Class Codes: B01L 2300/0864 comprising only one inlet and multiple receiving wells, e.g. for separation, splitting
• CPC Class Codes: B01L 2300/0867 Multiple inlets and one sample wells, e.g. mixing, dilution
• CPC Class Codes: B01L 2400/0415 electrical forces, e.g. electrokinetic
• CPC Class Codes: B01L 3/50273 characterised by the means or forces applied to move the fluids micropumps F04B19/006, of the membrane type F04B43/043
• CPC Class Codes: B01L 3/502784 specially adapted for droplet or plug flow, e.g. digital microfluidics automatic analysis using a stream of discrete samples in a tube system G01N35/08
• CPC Class Codes: B03C 5/026 using open-gradient differential dielectric separation, i.e. using electrodes of special shapes for non-uniform field creation, e.g. Fluid Integrated Circuit [FIC]
• CPC Class Codes: C02F 1/48 with magnetic or electric fields C02F1/46 takes precedence

Abstract

Devices for the manipulation of a suspended particle in an electric field gradient include a plurality of electrically isolated electrodes on a surface. A liquid composition is on the plurality of electrodes. The liquid composition covers the surface continuously between adjacent ones of the plurality of electrodes. The liquid composition has an exposed liquid surface for suspending a particle. The plurality of electrodes are configured to provide an electric field gradient for transporting the particle suspended in said liquid composition.

Claims

1. A device for the manipulation of a suspended particle in an electric field gradient comprising:

a plurality of electrically isolated electrodes on a surface; and

a liquid composition on said plurality of electrodes, said liquid composition covering said surface continuously between adjacent ones of said plurality of electrodes, said liquid composition having an exposed liquid surface defining a liquid/air interface for suspending a particle;

said plurality of electrodes configured to provide an electric field gradient for transporting the particle suspended in said liquid composition at said liquid/air interface; and

a particle suspended in said liquid composition at said liquid/air interface, wherein said particle is spaced apart from said plurality of electrodes.

2. The device of claim 1, wherein said liquid composition is selected from the group consisting of perfluorinated oil, silicone oil, fluorocarbons, hydrocarbons, and/or chemical and/or physical combinations thereof.

3. The device of claim 1, wherein said particle comprises a solid particle.

4. The device of claim 1, wherein said particle comprises a fluid droplet.

5. The device of claim 4, wherein said fluid droplet includes a carried component suspended, dissolved, or solubilized therein.

6. The device of claim 5, wherein said fluid droplet comprises water and said carried component is selected from the group consisting of nanoparticles, microparticles, surfactants, proteins, cells, viruses, drugs, toxins, chemical compounds, or combinations thereof.

7. The device of claim 5, wherein said fluid droplet comprises hydrocarbon or an organic compound and said carried component is selected from the group consisting of nanoparticles, microparticles, polymers, polymerizable monomers, surfactants, silicone compounds, and/or combinations thereof.

8. The device of claim 4, wherein said fluid droplet has a volume between about 0.01 μ

L and about 10 μ

L.

9. The device of claim 1, wherein said plurality of electrodes are configured to provide a first pathway for a first particle and a second pathway for a second particle, said first pathway and said second pathway having an intersection for combining said first particle and said second particle.

10. The device of claim 1, wherein ones of said plurality of electrodes comprises a conductive ring.

11. The device of claim 1, wherein said plurality of electrodes are configured in a two-dimensional matrix.

12. The device of claim 1, wherein said surface includes a first side having said plurality of electrodes positioned thereon, and a second side having a plurality of leads electrically connected to said plurality of electrodes, ones of the plurality of leads being connected to an alternating current source, a direct current source or ground, wherein the positions of said plurality of electrodes are selected to provide a dynamic non-uniform electric field pattern for transporting a particle along a pathway.

13. The device of claim 1, wherein said plurality of electrodes have a length of between about 0.1 and about 1 mm and a distance between adjacent ones of said plurality of electrodes between about 0.1 mm and about 1 mm.

14. The device of claim 1, further comprising a power source connected to said plurality of electrodes, said power source configured to provide an alternating current (AC) voltage of between about 50 V and about 500 V at a frequency between about 50 Hz and about 500 Hz to ones of said plurality of electrodes.

15. The device of claim 1, further comprising a power source connected to said plurality of electrodes, said power source configured to provide a direct current (DC) voltage between about 20 and about 500 V to ones of said plurality of electrodes.

16. The device of claim 1, wherein said plurality of electrodes are configured to provide an electric field gradient for applying force to a droplet suspended in the liquid fluid in opposing directions for separating the droplet into two droplets.

17. The device of claim 1, wherein the particle is suspended in said liquid composition at the liquid/air interface such that a portion of the particle contacts the liquid composition and another portion of the particle contacts air at the liquid/air interface.

18. A method for the manipulation of a suspended particle in an electric field gradient comprising:

configuring a plurality of electrodes on a surface to provide an electric field gradient for transporting a particle;

applying a liquid composition on the plurality of electrodes, the liquid composition having an exposed liquid surface defining a liquid/air interface for suspending a particle;

suspending the particle in the liquid composition at said liquid/air interface;

applying a voltage between selected ones of the plurality of electrodes to provide the electric field gradient, the electric field gradient having a pattern that defines a pathway for transporting the particle at said liquid/air interface; and

transporting the particle along the pathway defined by the electric field gradient at said liquid/air interface, wherein the particle is spaced apart from the plurality of electrodes.

19. The method of claim 18, wherein the liquid composition is selected from the group consisting of perfluorinated oil, silicone oil, fluorocarbons, hydrocarbons, and/or chemical and/or physical combinations thereof.

20. The method of claim 18, wherein the particle comprises a solid particle.

21. The method of claim 18, wherein the particle comprises a fluid droplet.

22. The method of claim 21, wherein the fluid droplet further comprises a carried component suspended, dissolved, or solubized therein.

23. The method of claim 22, wherein the fluid droplet comprises water and the carried component is selected from the group consisting of nanoparticles, microparticles, surfactants, proteins, cells, viruses, drugs, toxins, chemical compounds, or combinations thereof.

24. The method of claim 22, wherein the fluid droplet comprises hydrocarbon or an organic material and the carried component is selected from the group consisting of a nanoparticle, a microparticle, a polymer, a polymerizable monomer, a surfactant, a silicone compound, and/or combinations thereof.

25. The method of claim 22, wherein the fluid droplet has a volume between about 0.01 μ

L and about 10 μ

L.

26. The method of claim 18, wherein the pattern of the electric field gradient further defines a second pathway, the first pathway and the second pathway having a common intersection, the method comprising:

transporting a second particle along the second pathway; and

combining the first particle and the second particle at the intersection between the first pathway and the second pathway.

27. The method of claim 26, wherein the first droplet and the second droplet comprise constituents of an assay.

28. The method of claim 26, further comprising chemically reacting constituents of the first droplet with constituents of the second droplet.

29. The method of claim 26, wherein said combining step further comprises forming a solid and/or encapsulated particulate product.

30. The method of claim 18, wherein ones of the plurality of electrodes comprises a conductive ring.

31. The method of claim 18, further comprising configuring said plurality of electrodes in a two-dimensional matrix.

32. The method of claim 18, wherein the surface includes a first side having the plurality of electrodes positioned thereon, and a second side having a plurality of leads electrically connected to the plurality of electrodes, further comprising:

connecting ones of the plurality of leads to an alternating current source, a direct current source or ground; and

selecting the positions of the plurality of electrodes to provide a dynamic non-uniform electric field pattern for transporting the particle along the pathway.

33. The method of claim 18, wherein ones of the plurality of electrodes have a length of between about 0.1 and about 1 mm and the distance between electrodes ranges from between about 0.1 mm to about 1 mm.

34. The method of claim 18, further comprising applying an alternating current (AC) voltage of between about 50 V and about 500 V at a frequency between about 50 Hz and about 500 Hz to ones of the plurality of electrodes.

35. The method of claim 18, further comprising applying a direct current (DC) voltage between about 20 and about 500 V to ones of the plurality of electrodes.

36. The method of claim 18, further comprising:

providing an electric field gradient that applies force to a droplet suspended in the liquid fluid in two directions; and

separating the droplet into two droplets by applying the electric field gradient.

37. The method of claim 18, wherein the particle is suspended in said liquid composition at the liquid/air interface such that a portion of the particle contacts the liquid composition and another portion of the particle contacts air at the liquid/air interface.