Compositions and methods for liquid metering in microchannels

• US 8,936,945 B2
• Filed: 11/17/2005
• Issued: 01/20/2015
• Est. Priority Date: 11/17/2005
• Status: Active Grant

• Current Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Original Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Inventors: Handique, Kalyan, Burns, Mark A.
• Primary Examiner(s): Mui, Christine T
• Application Number:
  US11/281,977
• Publication Number:
  US 20070111302A1
• Time in Patent Office: 3,351 Days
• Field of Search: 436/180
• US Class Current: 436/180
• CPC Class Codes: B01F 25/431 Straight mixing tubes with baffles or obstructions that do not cause substantial pressure drop; Baffles therefor
• CPC Class Codes: B01F 25/431971 Mounted on the wall
• 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 33/30 Micromixers
• CPC Class Codes: B01L 2200/027 for microfluidic devices
• CPC Class Codes: B01L 2200/0605 Metering of fluids
• CPC Class Codes: B01L 2200/147 Employing temperature sensors
• CPC Class Codes: B01L 2300/0803 Disc shape
• CPC Class Codes: B01L 2300/1827 using resistive heater
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 2400/0442 thermal energy, e.g. vaporisation, bubble jet
• CPC Class Codes: B01L 2400/0487 fluid pressure, pneumatics
• CPC Class Codes: B01L 2400/0677 phase change valves; Meltable, freezing, dissolvable plugs; Destructible barriers
• CPC Class Codes: B01L 2400/0688 surface tension valves, capillary stop, capillary break
• CPC Class Codes: B01L 2400/0694 vents used to stop and induce flow, backpressure valves
• CPC Class Codes: B01L 3/502715 characterised by interfacing components, e.g. fluidic, electrical, optical or mechanical interfaces
• 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: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: Y10T 436/2575 Volumetric liquid transfer

Abstract

The movement and mixing of microdroplets through microchannels is described employing microscale devices, comprising microdroplet transport channels, reaction regions, electrophoresis modules, and radiation detectors. Microdroplets are metered into defined volumes and are subsequently incorporated into a variety of biological assays. Electronic components are fabricated on the same substrate material, allowing sensors and controlling circuitry to be incorporated in the same device.

Claims

1. A method, comprising the steps of:

(a) providing a device comprising

i) a microdroplet transport channel, said channel having one or more hydrophobic regions and a depth; and

ii) a gas port in fluidic communication with said channel configured to meter a microdroplet;

(b) introducing a liquid volume into said channel so as to create a liquid-containing channel and under conditions such that said liquid volume is confined by at least one of said hydrophobic regions; and

(c) dividing said liquid volume thereby defining said metered microdroplet, wherein said gas port introduces a volume of gas at a threshold metering pressure, wherein said threshold pressure is dependent upon said channel depth.

2. The method of claim 1, further comprising the step d) moving said metered microdroplet.

3. The method of claim 2, wherein said metered microdroplet is moved into a reaction chamber.

7. The method of claim 1, wherein said transport channel and said gas inlet ports are etched.

4. A method, comprising the steps of:

(a) providing a device comprising

i) a microdroplet transport channel, said channel having one or more hydrophobic regions; and

ii) a plurality of gas ports in fluidic communication with said channel wherein the distances between said one or more hydrophobic regions and said plurality of gas ports are configured to meter a range of predetermined liquid volumes;

(b) introducing a liquid volume into said channel so as to create a liquid-containing channel and under conditions such that said liquid volume is confined by at least one of said hydrophobic regions; and

(c) dividing said liquid volume thereby creating one of said predetermined metered liquid volumes within said range of predetermined metered liquid volumes, wherein one of said plurality of gas ports introduce a volume of gas, wherein said volumes of gas is at a threshold metering pressure.

5. The method of claim 4, further comprising the step d) moving said plurality of predetermined metered liquid volumes.

6. The method of claim 5, wherein said plurality of predetermined metered liquid volumes are moved into a reaction chamber.

8. The method of claim 4, wherein said transport channel and said gas inlet ports are etched.