METHOD AND APPARATUS FOR FLUID DISPERSION

• US 20100172803A1
• Filed: 03/17/2010
• Published: 07/08/2010
• Est. Priority Date: 06/28/2002
• Status: Active Grant

• Current Assignee: President and Fellows of Harvard College (Harvard Corporation), The Governing Council of the University of Toronto (University of Toronto)
• Original Assignee: President and Fellows of Harvard College (Harvard Corporation), The Governing Council of the University of Toronto (University of Toronto)
• Inventors: Garstecki, Piotr, Bontoux, Nathalie, Whitesides, George M., Link, Darren R., Stone, Howard A., Weitz, David A., Gitlin, Irina, Kumacheva, Eugenia, Anna, Shelley L., Diluzio, Willow
• Granted Patent: US 8,337,778 B2
• Time in Patent Office: Days
• US Class Current: 422/100
• CPC Class Codes: B01F 2215/0431 Numerical size values, e.g. diameter of a hole or conduit, area, volume, length, width, or ratios thereof
• CPC Class Codes: B01F 2215/045 Numerical flow-rate values
• CPC Class Codes: B01F 23/41 Emulsifying
• CPC Class Codes: B01F 25/45 Mixers in which the materials to be mixed are pressed together through orifices or interstitial spaces, e.g. between beads B01F25/44 takes precedence
• CPC Class Codes: B01F 25/4521 the components being pressed through orifices in elements, e.g. flat plates or cylinders, which obstruct the whole diameter of the tube
• CPC Class Codes: B01F 33/3011 using a sheathing stream of a fluid surrounding a central stream of a different fluid, e.g. for reducing the cross-section of the central stream or to produce droplets from the central stream
• 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: B05B 7/0408 with arrangements for mixing two or more liquids
• CPC Class Codes: B05B 7/0416 with arrangements for mixing one gas and one liquid
• CPC Class Codes: B05B 7/0441 with one inner conduit of liquid surrounded by an external conduit of gas upstream the mixing chamber
• CPC Class Codes: Y10S 516/924 Significant dispersive or manipulative operation or step in making or stabilizing colloid system
• CPC Class Codes: Y10S 516/927 in situ formation of a colloid system making or stabilizing agent which chemical reaction
• CPC Class Codes: Y10T 137/0324 With control of flow by a condition or characteristic of a fluid
• CPC Class Codes: Y10T 137/0329 Mixing of plural fluids of diverse characteristics or conditions
• CPC Class Codes: Y10T 137/206 Flow affected by fluid contact, energy field or coanda effect [e.g., pure fluid device or system]
• CPC Class Codes: Y10T 137/87346 Including mixing feature
• CPC Class Codes: Y10T 29/49002 Electrical device making
• CPC Class Codes: Y10T 436/2575 Volumetric liquid transfer

Abstract

A microfluidic method and device for focusing and/or forming discontinuous sections of similar or dissimilar size in a fluid is provided. The device can be fabricated simply from readily-available, inexpensive material using simple techniques.

Claims

1. A device comprising:

a microfluidic interconnected region comprising an upstream portion, a downstream portion and a dimensionally-restricted section defining the downstream portion of the microfluidic interconnected region, the microfluidic interconnected region being connected at its upstream portion to two or more microfluidic channels.

2. The device of claim 1, wherein the dimensionally-restricted section comprises a non-valved orifice.

3. The device of claim 1, wherein the dimensionally-restricted section is formed by at least an extension of a wall defining the interconnected region.

4. The device of claim 1, wherein the microfluidic interconnected region and the two or more microfluidic channels are part of a single integral unit.

5. The device of claim 1, wherein the microfluidic interconnected region, the upstream portion, and the downstream portion are each contained within a microfluidic device.

6. The device of claim 1, wherein the microfluidic interconnected region has a maximum cross-sectional diameter of less than 50 microns.

7. The device of claim 1, wherein the downstream portion has a largest dimension perpendicular to fluid flow of less than about 1 mm.

8. The device of claim 1, wherein the device comprises two microfluidic inlet channels each containing a continuous fluid and one microfluidic inlet channel containing a subject fluid.

9. The device of claim 8, wherein the subject fluid forms discontinuous sections at the interconnected region surrounded by the continuous fluid, at least some of the discontinuous sections having a maximum dimension of less than 100 microns.

10. The device of claim 8, wherein the continuous fluid completely circumferentially surrounds the subject fluid when the continuous fluid and the subject fluid flow through the microfluidic interconnected region.

11. The device of claim 8, wherein the microfluidic inlet channel containing the subject fluid has an outlet upstream of the dimensionally-restricted section.

12. The device of claim 8, wherein the interconnected region and the microfluidic inlet channel containing the subject fluid comprise a central axis.

13. The device of claim 8, wherein the continuous phase comprises oil.

14. The device of claim 8, wherein the subject fluid comprises water.

15. The device of claim 8, wherein each the subject fluid and the continuous fluid each have a flow rate, and the ratio of the flow rate of the subject fluid to the flow rate of the continuous fluid is less than 1:

5.

16. The device of claim 9, wherein the continuous fluid is immiscible in the subject fluid within the time frame of formation of the discontinuous sections of the subject fluid.

17. The device of claim 9, wherein at least some of the discontinuous sections have a maximum dimension of less than 80 microns.

18. The device of claim 9, wherein at least some of the discontinuous sections have a maximum dimension of less than 60 microns.

19. The device of claim 9, wherein at least some of the discontinuous sections have a maximum dimension of less than 40 microns.

20. The device of claim 9, wherein at least some of the discontinuous sections have a maximum dimension of less than 20 microns.