Method of using actuators for microfluidics without moving parts

• US 7,255,780 B2
• Filed: 05/06/2003
• Issued: 08/14/2007
• Est. Priority Date: 01/25/1999
• Status: Expired due to Term

• Current Assignee: Advanced Liquid Logic, Inc. (Illumina Incorporated)
• Original Assignee: Nanolytics, Inc. (Illumina Incorporated)
• Inventors: Shenderov, Alexander David
• Primary Examiner(s): NOGUEROLA, ALEXANDER STEPHAN
• Application Number:
  US10/430,816
• Publication Number:
  US 20040031688A1
• Time in Patent Office: 1,561 Days
• Field of Search: 204600-605, 204450-455, 204/643, 204/547
• US Class Current: 204/450
• CPC Class Codes: B01F 2025/913 Vortex flow, i.e. flow spiraling in a tangential direction and moving in an axial direction
• 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: B01L 2200/0673 Handling of plugs of fluid surrounded by immiscible fluid
• 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 2200/16 Reagents, handling or storing thereof
• 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 2300/0867 Multiple inlets and one sample wells, e.g. mixing, dilution
• CPC Class Codes: B01L 2300/089 Virtual walls for guiding liquids
• CPC Class Codes: B01L 2400/0415 electrical forces, e.g. electrokinetic
• CPC Class Codes: B01L 2400/0427 Electrowetting
• CPC Class Codes: B01L 3/502738 characterised by integrated valves microvalves F16K99/0001
• CPC Class Codes: B01L 3/502746 characterised by the means for controlling flow resistance, e.g. flow controllers, baffles B01L3/502738 takes precedence
• 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: F04B 17/00 Pumps characterised by combination with, or adaptation to, specific driving engines or motors
• CPC Class Codes: F04B 19/006 Micropumps F04B43/043 and F04B43/095 take precedence
• CPC Class Codes: F16K 99/0001 Microvalves microdevices B81B1/00; manufacture or treatment of devices or systems in or on a substrate B81C1/00; microfluidic structures B01L3/5027; micropumps F04B19/006
• CPC Class Codes: F16K 99/0017 Capillary or surface tension valves, e.g. using electro-wetting or electro-capillarity effects
• CPC Class Codes: G02B 26/005 : based on electrowetting

Abstract

A series of microactuators for manipulating small quantities of liquids, and methods of using these for manipulating liquids, are disclosed. The microactuators are based on the phenomenon of electrowetting and contain no moving parts. The force acting on the liquid is a potential-dependent gradient of adhesion energy between the liquid and a solid insulating surface.

Claims

1. A method of performing a chemical or biochemical reaction in a droplet, comprising:

providing a device comprising;

a housing having an internal volume filled with a liquid;

a plurality of adjacent, electrically isolated lower electrodes positioned in the housing, wherein sequential lower electrodes have substantially contiguous, hydrophobic surfaces, the lower electrodes defining a droplet travel path; and

at least one electrically isolated upper electrode positioned in the housing opposite the lower electrodes, the upper electrode being covered with a hydrophobic surface;

introducing an electrolytic droplet immiscible with said liquid into the housing and onto a hydrophobic surface of a first lower electrode, the electrolytic droplet containing at least one reactive material;

applying an electrical potential to a second lower electrode adjacent the first lower electrode sufficient to cause the hydrophobic surface thereof to become temporarily more hydrophilic, thereby inducing the electrolytic droplet to move from the first electrode to the second electrode;

repeating the applying step to continue inducing movement of the electrolytic droplet between adjacent electrodes along the droplet travel path to a predetermined location thereon; and

carrying out a chemical or biochemical reaction utilizing the reactive material contained in the electrolytic droplet.

2. The method defined in claim 1, wherein the reactive material is selected from the group consisting of:

chemical regents, biochemical reagents, chemical reactants, and biochemical reactants.

3. The method defined in claim 1, wherein the electrolytic droplet comprises an aqueous solution.

4. The method defined in claim 1, wherein the at least one upper electrode is a single electrode that covers substantially all of the lower electrodes.

5. The method defined in claim 1, wherein the device further comprises a drop meter that dispenses electrolytic droplets, and wherein the introducing step comprises introducing the electrolytic droplet with the drop meter.

6. The method defined in claim 1, wherein the reaction carried out is a biochemical assay.