Electrowetting Pumping Device And Use For Measuring Electrical Activity

• US 20080210558A1
• Filed: 06/16/2006
• Published: 09/04/2008
• Est. Priority Date: 06/17/2005
• Status: Active Grant

• Current Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Original Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Inventors: Sauter-Starace, Fabien, Berthier, Jean
• Granted Patent: US 8,075,754 B2
• Time in Patent Office: Days
• US Class Current: 204/450
• 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: B01F 33/30351 using hydrophilic/hydrophobic surfaces
• CPC Class Codes: B01L 2300/0645 Electrodes
• 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 2300/089 Virtual walls for guiding liquids
• CPC Class Codes: B01L 2400/0427 Electrowetting
• 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 3/502792 for moving individual droplets on a plate, e.g. by locally altering surface tension
• CPC Class Codes: F04B 19/006 Micropumps F04B43/043 and F04B43/095 take precedence
• CPC Class Codes: G01N 33/48728 Investigating individual cells, e.g. by patch clamp, voltage clamp investigating individual particles in general G01N15/10

Abstract

The invention relates to a method for pumping through an orifice (30, 31) of a first substrate (1), a first volume of liquid (2) in contact with a first hydrophobic surface of said substrate, wherein a pressure variation between the first volume of liquid and a second volume of liquid (2′), located in contact with said orifice and a second hydrophobic surface of said substrate, is achieved by electrowetting.

Claims

1. A method for pumping through an orifice (30, 31) of a first substrate (1), a first volume of liquid (2), in contact with a first hydrophobic surface of said substrate, wherein a pressure variation between said first volume of liquid and a second volume of liquid (2′

), located in contact with said orifice and a second hydrophobic surface of said substrate, is achieved by electrowetting.

2. The method according to claims 1, the first and/or the second volume of liquid being confined, at least during pumping, between said first hydrophobic surface and/or said second hydrophobic surface and a second and/or a third substrate (100, 100′

).

3. The method according to any of claims 1 or 2, making use of an electrowetting device, including said first substrate, the first surface of which is hydrophobic or covered with a hydrophobic layer (8), and a plurality of electrodes (4) positioned under said hydrophobic layer, pumping being obtained by activating these electrodes (4).

4. The method according to claim 3, the second surface of the electrowetting device including a hydrophobic layer (8′

), and a plurality of electrodes (4′

) positioned under said hydrophobic layer.

5. The method according to any of claims 1 to 4, the first and second surfaces of the substrate being parallel to each other and to a plane defined by the substrate.

6. The method according to any of claims 1 to 4, the first surface of the substrate being parallel to a plane defined by the substrate, and the second surface being defined by at least one portion of the wall of said orifice (30, 31).

7. The method according to any of claims 1 to 6, the first and/or the second volume of liquid consisting of a drop of liquid.

8. The method according to claim 7, the drop(s) being formed from one or more reservoirs (21, 22).

9. The method according to any of claims 7 or 8, the drop(s) having a volume between 1 nl and 100 μ

l.

10. A method for analyzing a liquid from a first volume of liquid (2) including:

contacting this first volume of liquid with a hydrophobic surface (8),

pumping this first volume of liquid by means of a second volume of liquid, according to a method according to any of claims 1 to 9, in order to position it against said orifice (30, 31),

measuring the electric activity of said liquid.

11. The method according to claim 10, the electric activity measurement being performed on a single cell (27) contained in the first volume of liquid (2).

12. The method according to claim 11, the measurement being a measurement on one channel or on channels of the cell or a cell membrane.

13. The method according to claim 10, the electric activity measurement being performed on a biological object such as an embryo or a bovine ovocyte.

14. A device for pumping volume of liquid, including:

a substrate (1), having a first and a second surface, at least one of which is hydrophobic or covered with a hydrophobic layer, and at least one orifice (30, 31) crossing through said substrate,

means (4) for displacing, by electrowetting, at least one volume of liquid on one of said faces of the substrate.

15. The device according to claim 14, said orifice (30, 31) including a first portion, with a first maximum dimension, and a second portion, having a second maximum dimension, larger than the first.

16. The device according to claim 14 or 15, the means (4) for displacing drops by electrowetting including a plurality of electrodes (4) positioned under said hydrophobic layer or surface.

17. The device according to claim 14 to 16, the second surface of the electrowetting device being hydrophobic or including a hydrophobic layer (8′

), and a plurality of electrodes (4′

) positioned under said hydrophobic layer or surface.

18. The device according to any of claims 14 to 17, the first and second surfaces of the substrate being parallel to each other and in a plane defined by the substrate.

19. The device according to any of claims 14 to 17, the first surface of the substrate being parallel to a plane defined by the substrate, and the second surface being defined by at least one portion of the wall of said orifice (30, 31).

20. The device according to any of claims 14 to 19, further including a first dielectric layer (6), in part under the hydrophobic layer (8) or surface

21. The device according to claim 20, further including a second dielectric layer (6′

), positioned on a surface parallel to the first surface.

22. The device according to any of claims 14 to 21, further including a second substrate and/or a third substrate (100, 100′

), positioned facing the first and/or the second surfaces.

23. The device according to claim 22, the second and/or the third substrate further including a hydrophobic surface layer (108, 108′

).

24. The device according to claim 22 or 23, the second and/or the third substrate further including an electrode (112, 112′

).

25. A device for analyzing a first volume of liquid, including one or more devices according to any of claims 14 to 14, and means (38, 38′

) for measuring the electrical activity of a volume of liquid associated with at least one orifice (30, 31).

26. The device according to claim 25, the electric activity measurement means associated with at least one orifice including first and second electrodes (38, 38′

).

27. The device according to any of claims 14 to 26, further comprising at least one reservoir (21, 22) of liquid and means for bringing drops of liquid from this reservoir or from at least one of these reservoirs towards one of the orifices (30, 31).

28. The device according to claim 27, the means for bringing drops of liquid towards one of the orifices being means (4) for displacing drops by electrowetting.