Droplet Actuator Structures

• US 20100236927A1
• Filed: 10/17/2008
• Published: 09/23/2010
• Est. Priority Date: 10/17/2007
• Status: Active Grant

• Current Assignee: Advanced Liquid Logic, Inc. (Illumina Incorporated)
• Original Assignee: Advanced Liquid Logic, Inc. (Illumina Incorporated)
• Inventors: Pope, Lavern, Pamula, Vamsee K., Pollack, Michael G.
• Granted Patent: US 8,454,905 B2
• Time in Patent Office: Days
• US Class Current: 204/450
• 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 2300/0887 Laminated structure
• CPC Class Codes: B01L 2300/161 Control and use of surface tension forces, e.g. hydrophobic, hydrophilic
• CPC Class Codes: B01L 2400/0427 Electrowetting
• CPC Class Codes: B01L 3/502792 for moving individual droplets on a plate, e.g. by locally altering surface tension
• CPC Class Codes: Y10T 436/11 Automated chemical analysis
• CPC Class Codes: Y10T 436/25 including sample preparation
• CPC Class Codes: Y10T 436/2575 Volumetric liquid transfer

Abstract

A droplet actuator comprising a substrate comprising an electrode coupled to a voltage source, wherein the droplet actuator is configured such that when voltage is applied to the electrode, an electrostatic energy gradient is established at a surface of the substrate which causes a droplet to be transported in a direction established by the energy gradient. Related methods and other embodiments are also provided.

Claims

1. A droplet actuator comprising a substrate comprising an electrode coupled to a voltage source, wherein the droplet actuator is configured such that when voltage is applied to the electrode, an electrostatic energy gradient is established at a surface of the substrate which causes a droplet to be transported in a direction established by the energy gradient.

2. The droplet actuator of claim 1 further comprising a two terminal electrode composed of a resistive material, such that the electrode functions as a resistor with a spatial distribution of electric potential along its length.

3. The droplet actuator of claim 1 wherein the droplet actuator is:

(a) coupled to a second voltage source; and

(b) configured such that when voltage to the first and second voltage sources, an electrostatic energy gradient is established at a surface of the substrate which causes a droplet to be transported in a direction established by the energy gradient.

4. The droplet actuator of claim 3 wherein the electrostatic energy gradient at the surface of the substrate is established by a voltage difference between the first and second voltage sources.

5. The droplet actuator of claim 6 wherein the voltage difference ranges from about >

0 volts to about 300 volts.

6. The droplet actuator of claim 1 wherein the electrostatic energy gradient results from a gradient in thickness of a material layered above the electrode.

7. The droplet actuator of claim 1 wherein the electrostatic energy gradient results from a difference in thickness of a dielectric material layered above the electrode.

8. The droplet actuator of claim 1 wherein the electrostatic energy gradient results from a gradient in dielectric constant of a dielectric material layered above the electrode.

9. The droplet actuator of claim 1 wherein the electrostatic energy gradient results from a gradient in distance of the electrode'"'"'s surface from the substrate'"'"'s surface.

10. The droplet actuator of claim 1 wherein the electrostatic energy gradient is continuous.

11. The droplet actuator of claim 1 wherein the electrostatic energy gradient is discontinuous.

12. A method of transporting a droplet, the method comprising:

(a) providing a droplet actuator comprising a substrate comprising;

(i) a droplet operations surface;

(ii) an electrode associated with the substrate, coupled to a voltage source, and configured such that when voltage is applied to the electrode, an electrostatic energy gradient is established at the droplet operations surface;

(b) providing a droplet on the droplet operations surface;

(c) applying voltage to the electrode and thereby causing the droplet to be transported in a direction established by the energy gradient.

13. The method of claim 12 wherein the droplet comprises one or more beads.

14. The method of claim 12 wherein the droplet comprises one or more magnetically responsive beads.

15. The method of claim 12 wherein the droplet comprises one or more substantially non-magnetically responsive beads.

16. The method of claim 12 wherein the droplet comprises one or more pre-selected biological cells.

17. A droplet actuator comprising:

(a) a substrate;

(b) an electrode path associated with the substrate;

(c) a dielectric layer overlying the electrode, wherein;

(i) the dielectric layer has a thickness; and

(ii) comprises region in which the thickness varies.

18. The droplet actuator of claim 17 wherein the region overlies a single electrode of the electrode path.

19. The droplet actuator of claim 17 wherein the region overlies two or more electrodes of the electrode path.

20. The droplet actuator of claim 17 wherein the region lies generally between two electrodes of the electrode path.

21. The droplet actuator of claim 17 wherein droplet actuator comprises at least two zones of generally uniform thickness separated by the segment.

22. The droplet actuator of claim 17 wherein droplet actuator comprises at three zones of generally uniform thickness separated by the segment.