Droplet manipulation system and method

• US 9,180,450 B2
• Filed: 07/30/2014
• Issued: 11/10/2015
• Est. Priority Date: 09/24/2002
• Status: Active Grant

• Current Assignee: Duke University
• Original Assignee: Advanced Liquid Logic, Inc. (Illumina Incorporated)
• Inventors: Pollack, Michael G., Pamula, Vamsee K., Fair, Richard B.
• Primary Examiner(s): NOGUEROLA, ALEXANDER STEPHAN
• Application Number:
  US14/446,733
• Publication Number:
  US 20140339082A1
• Time in Patent Office: 468 Days
• US Class Current: 1/1
• CPC Class Codes: B01F 31/65 the materials to be mixed being directly submitted to a pulsating movement, e.g. by means of an oscillating piston or air column
• 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 2200/06 Fluid handling related problems
• CPC Class Codes: B01L 2200/0605 Metering of fluids
• CPC Class Codes: B01L 2200/10 Integrating sample preparation and analysis in single entity, e.g. lab-on-a-chip concept
• CPC Class Codes: B01L 2300/089 Virtual walls for guiding liquids
• CPC Class Codes: B01L 2300/161 Control and use of surface tension forces, e.g. hydrophobic, hydrophilic
• CPC Class Codes: B01L 2300/165 Specific details about hydrophobic, oleophobic surfaces
• CPC Class Codes: B01L 2400/0415 electrical forces, e.g. electrokinetic
• CPC Class Codes: B01L 2400/0427 Electrowetting
• CPC Class Codes: B01L 3/00 Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
• CPC Class Codes: B01L 3/5027 by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip B01L3/5023 takes precedence; micromixers B01F33/30; microreactors for synthesis B01J19/0093; microcapillary devices in general B81B1/00
• 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: B01L 3/502792 for moving individual droplets on a plate, e.g. by locally altering surface tension
• CPC Class Codes: B41J 2002/14395 Electrowetting
• CPC Class Codes: C25B 9/00 Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features
• CPC Class Codes: G01N 27/44791 Microapparatus sample containers with integrated microfluidic structures B01L3/5027
• CPC Class Codes: G02B 26/005 : based on electrowetting

Abstract

Methods are provided for manipulating droplets. The methods include providing the droplet on a surface comprising an array of electrodes and a substantially co-planer array of reference elements, wherein the droplet is disposed on a first one of the electrodes, and the droplet at least partially overlaps a second one of the electrodes and an intervening one of the reference elements disposed between the first and second electrodes. The methods further include activating the first and second electrodes to spread at least a portion of the droplet across the second electrode and deactivating the first electrode to move the droplet from the first electrode to the second electrode.

Claims

1. A system for manipulating droplets, comprising:

(a) a microactuator, comprising;

i. a base substrate comprising an array of rows of electrodes; and

ii. an insulating layer atop the electrodes, wherein the electrodes in the array are misaligned such that the electrodes in any given row are offset from the electrodes of adjacent rows;

(b) an electrode selector;

(c) a voltage source; and

wherein the system is configured such that a voltage-induced electrowetting potential is delivered to the electrodes to effect electrowetting-based droplet operations.

2. The system of claim 1 further comprising a top plate arranged to contain droplets on the electrodes.

3. The system of claim 1 wherein the electrodes comprise column biasing electrodes.

4. The system of claim 1 wherein the electrodes have a common size and shape.

5. The system of claim 1 wherein the insulating layer atop the electrodes is a common dielectric layer coating all of the electrodes.

6. The system of claim 1 wherein the electrode selector is configured for sequentially activating and de-activating one or more selected electrodes to sequentially bias the selected electrodes to an actuation voltage.

7. The system of claim 6 wherein the electrode selector comprises a microprocessor.

8. A method of operating a droplet manipulating system comprising:

(a) providing the system of claim 1;

(b) providing a droplet on the base substrate of the microactuator of claim 1;

(c) actuating the droplet by creating a circuit inclusive with the droplet by, via the electrode selector;

(i) providing an actuation voltage from a voltage source to a first of the electrodes; and

(ii) providing a ground or reference potential to a second of the electrodes,

wherein the second of the electrodes is adjacent to the first of the electrodes.

9. The method of claim 8 wherein the first and second electrodes have a common size and shape.

10. The method of claim 8 further comprising further actuating the droplet by, via the electrode selector:

(a) providing an actuation voltage to a third of the electrodes, which is adjacent to the first of the electrodes; and

(b) maintaining a ground or reference potential to the second of the electrodes.

11. The method of claim 8 further comprising further actuating the droplet by, via the electrode selector:

(a) providing an actuation voltage to a third of the electrodes, which is adjacent to the first of the electrodes; and

(b) providing a ground or reference potential to a fourth of the electrodes, wherein the fourth of the electrodes is adjacent to the third of the electrodes.

12. The method of claim 11 wherein the method causes droplet transport along gaps between electrodes.

13. The method of claim 11 wherein the method is part of a droplet transport operation.

14. The method of claim 11 wherein the method is part of a droplet splitting operation.