Microfluidic device and methods for construction and application

• US 20060108012A1
• Filed: 11/14/2003
• Published: 05/25/2006
• Est. Priority Date: 11/14/2002
• Status: Active Grant

• Current Assignee: Q Chip Ltd.
• Original Assignee: Q Chip Ltd.
• Inventors: Barrow, David Anthony, Harries, Nicola, Bouris, Kostas, Jones, Tyrone Gwyn
• Granted Patent: US 7,802,591 B2
• Time in Patent Office: Days
• US Class Current: 137/806
• 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: B01L 2200/0636 Focussing flows, e.g. to laminate flows
• CPC Class Codes: B01L 2200/0673 Handling of plugs of fluid surrounded by immiscible fluid
• CPC Class Codes: B01L 2300/0864 comprising only one inlet and multiple receiving wells, e.g. for separation, splitting
• CPC Class Codes: B01L 2300/0867 Multiple inlets and one sample wells, e.g. mixing, dilution
• CPC Class Codes: B01L 2300/087 Multiple sequential chambers
• CPC Class Codes: B01L 2300/0883 Serpentine channels
• CPC Class Codes: B01L 2300/0887 Laminated structure
• CPC Class Codes: B01L 2400/0409 centrifugal forces
• CPC Class Codes: B01L 2400/0415 electrical forces, e.g. electrokinetic
• CPC Class Codes: B01L 2400/0427 Electrowetting
• CPC Class Codes: B01L 2400/0487 fluid pressure, pneumatics
• 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 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: Y10T 137/2076 Utilizing diverse fluids
• CPC Class Codes: Y10T 137/2224 Structure of body of device
• CPC Class Codes: Y10T 137/8593 Systems

Abstract

A microfluidic device comprises first and second inlet passages (13) for respective immiscible fluids, these inlet passages merging into a third passage (8) along which the two fluids flow under parallel laminar flow conditions, the third passage being formed with a constriction or other discontinuity (9) causing the two fluids to form into a flow of alternate segments.

Claims

1-20. -20. (canceled)

21. A device comprising first and second inlet passages for respective immiscible fluids, the first and second inlet passages merging into a third passage along which, in use, the two fluids flow under parallel laminar flow conditions, the third passage being formed with a constriction or other discontinuity, in use, causing the two fluids to form into a flow of alternate segments.

22. A device as claimed in claim 21, in which downstream portions of the inlet passages extend parallel with each other before merging to form the third passage.

23. A device as claimed in claim 21, in which said other discontinuity in the third passage comprises a region of changed surface energy.

24. A device as claimed in claim 21, in which said other discontinuity comprises a region of altered or alterable contact angle.

25. A device as claimed in claim 21, in which said other discontinuity comprises one or more further passages joining the third passage.

26. A device as claimed in claim 21, comprising a further inlet passage for a third fluid, the further inlet passage merging into the third passage upstream of the constriction or other discontinuity.

27. A device as claimed in claim 21, in which the third or outlet passage is formed with a second constriction or other discontinuity downstream of the first constriction or other discontinuity.

28. A device as claimed in claim 21, wherein the surfaces of the third passage which, in use, are in contact with said fluids comprise a fluoropolymer.

29. A device as claimed in claim 21, further comprising a source of electromagnetic radiation for polymerising or cross-linking the content (or part) of liquid segments produced downstream of the constriction or other discontinuity.

30. A device as claimed in claim 21 wherein the third passage is provided with an enlargement in cross-section downstream of the constriction or other discontinuity.

31. A method of producing a segmented flow of first and second immiscible fluids comprising

(i) providing a device with a first conduit provided with a constriction or other discontinuity

(ii) causing the first and second immiscible fluids to flow under laminar flow conditions along said first conduit, wherein the constriction or other discontinuity causes the first and second immiscible fluids to form into a flow of alternate segments downstream of the constriction or other discontinuity.

32. A method as claimed in claim 31 wherein the device is provided with first and second inlet passages for the delivery of the first and second immiscible fluids respectively to the first conduit.

33. A method as claimed in claim 31 wherein the first and second inlet passages merge into the first conduit.

34. A method as claimed in claim 31 wherein the first and second inlet passages merge into the first conduit and downstream portions of the first and second inlet passages extend parallel with each other before merging to form the first conduit.

35. A method according to claim 31 wherein the surface of said first conduit in contact with said first and second immiscible fluids comprises a fluoropolymer.

36. A method according to claim 31 wherein the flow rates of the first and second immiscible fluids in the first conduit are mutually different.

37. A method according to claim 31 wherein the first and second immiscible fluids are exposed to ultra-violet radiation downstream of the constriction or other discontinuity.

38. A method according to claim 31 wherein the contents (or part) of liquid segments are polymerised or cross-linked by exposure to electromagnetic radiation.

39. A method as claimed in claim 31 comprising causing segments of at least one of the first and second fluids to form a substantially spherical shape.

40. A fluid manipulation device comprising first and second ducts for the passage of respective immiscible fluids, each of said first and second ducts having a respective inlet for the introduction of said respective fluid into said device, wherein said first and second ducts join to form a third duct along which, in use, the first and second fluids flow under laminar flow conditions, the third duct being formed with a constriction, the constriction causing, in use, the first and second fluids to form into a flow of alternate segments, wherein the device comprises two substrates disposed face-to-face, the surface of at least one of the substrates being profiled such that the first, second and third ducts are defined between the two substrates, the surfaces of the third duct that, in use, comes into contact with one or both of the first or second fluid comprising a fluoropolymer.

41. A fluid manipulation device according to claim 40 wherein the surfaces of the first and second ducts that, in use, are in contact with the respective first and second fluids comprise a fluoropolymer.

42. A fluid manipulation device according to claim 40 wherein the two substrates are held together by outer members.