Method and device for controlling liquid flow on the surface of a microfluidic chip

• US 7,216,660 B2
• Filed: 11/02/2001
• Issued: 05/15/2007
• Est. Priority Date: 11/02/2000
• Status: Expired due to Fees

• Current Assignee: California Institute of Technology
• Original Assignee: Princeton University
• Inventors: Wagner, Sigurd, Troian, Sandra M., Darhuber, Anton A.
• Primary Examiner(s): CHAMBERS, A MICHAEL
• Application Number:
  US10/016,294
• Publication Number:
  US 20020150683A1
• Time in Patent Office: 2,020 Days
• Field of Search: 137/341, 137/828, 137/833, 137/13, 137/807, 204/601
• US Class Current: 137/13
• CPC Class Codes: B01F 2035/99 Heating
• CPC Class Codes: B01F 2215/0422 Numerical values of angles
• 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 2215/0477 Numerical time values
• CPC Class Codes: B01F 2215/0481 Numerical speed values
• 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 33/30351 using hydrophilic/hydrophobic surfaces
• CPC Class Codes: B01F 35/93 arranged inside the receptacle
• CPC Class Codes: B01L 2300/089 Virtual walls for guiding liquids
• CPC Class Codes: B01L 2300/1827 using resistive heater
• CPC Class Codes: B01L 2400/0442 thermal energy, e.g. vaporisation, bubble jet
• CPC Class Codes: B01L 2400/0448 Marangoni flow; Thermocapillary effect
• CPC Class Codes: B01L 3/502707 characterised by the manufacture of the container or its components by shaping or joining plastic parts B29C59/00, B29C65/00; by laminating B32B37/00; manufacture of microstructural devices in general B81C
• 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: Y10T 137/0391 Affecting flow by the addition of material or energy
• CPC Class Codes: Y10T 137/2082 Utilizing particular fluid
• CPC Class Codes: Y10T 137/2196 Acoustical or thermal energy
• CPC Class Codes: Y10T 137/2224 Structure of body of device

Abstract

The invention is directed to a method and device for routing, mixing, or reacting droplets or liquid microstreams along the surface of a flat substrate. The flow of liquid microstreams or microdroplets along designated pathways is confined by chemical surface patterning. Individually addressable heating elements, which are embedded in the substrate, can be used to generate flow via thermocapillary effects or to trigger or quench chemical reactions. The open architecture allows the liquid to remain in constant contact with the ambient atmosphere. The device can be used for microfluidic applications or as a surface reactor or biosensor, among other applications.

Claims

1. A method for routing a liquid comprising the steps of:

receiving said liquid on a patterned surface having an open architecture, said patterned surface comprises one or more hydrophobic portions confining a hydrophilic surface to form a pathway; and

individually activating one or more heating elements,

wherein said heating elements are in registry with said patterned surface for selectively heating said patterned surface under conditions effective for routing said liquid along said hydrophilic surface and said one or more hydrophobic portions confines said liquid in said hydrophilic surface.

2. A device for routing a liquid comprising:

a patterned surface having an open architecture, said patterned surface comprising one or more hydrophobic portions confining a hydrophilic surface to form a pathway;

one or more heating elements in registry with said patterned surface; and

means for individually activating one or more of said one or more heating elements, for selectively heating of said patterned surface under conditions effective for routing said liquid along said hydrophilic surface and flow of said liquid is by thermocapillary shear stresses said one or more hydrophobic portions confines said liquid in said hydrophilic surface.

3. A method for dividing a stream of liquid comprising the steps of:

receiving said stream of liquid on a patterned surface having an open architecture, said patterned surface comprises one or more hydrophobic portions confining a hydrophilic surface to form a pathway; and

individually activating one or more heating elements,

wherein said heating elements are in registry with said patterned surface for selectively heating said patterned surface under conditions effective for dividing said stream of liquid into one or more droplets and said one or more hydrophobic portions confines said liquid in said hydrophilic surface.

4. A device for dividing a stream of a liquid comprising:

a patterned surface adapted for receiving said stream of liquid, said patterned surface having an open architecture comprising one or more hydrophobic portions confining a hydrophilic surface to form a pathway;

one or more heating elements in registry with said patterned surface; and

means for individually activating one or more of said one or more heating elements, for selectively heating of said patterned surface under conditions effective for dividing said stream of liquid into one or more droplets and said hydrophobic portions confines said liquid in said hydrophilic surface.

5. A method for mixing two or more liquids comprising the steps of:

receiving said two or more liquids on a patterned surface, said patterned surface having an open architecture, said patterned surface comprising one or more hydrophobic portions confining a hydrophilic surface to form a pathway, each of said liquids being received in one of said pathways, said pathways being interconnected; and

individually activating one or more heating elements,

wherein said heating elements are in registry with said patterned surface for selectively heating said patterned surface under conditions effective for mixing said two or more liquids in at least one of said pathways and said one or more hydrophobic portions confines said liquid in said hydrophilic surface.

6. A device for mixing two or more liquids comprising:

a patterned surface, said patterned surface comprising one or more hydrophobic portions confining a hydrophilic surface to form a pathway, each of said liquids being received in one of said pathways, said pathways being interconnected;

one or more heating elements in registry with said patterned surface; and

means for individually activating one or more of said one or more heating elements, for selectively heating of said patterned surface under conditions effective for mixing said two or more liquids in at least one of said pathways and said one or more hydrophobic portions confines said liquid in said hydrophilic surface.

7. A method for detecting an airborne material in gaseous, particulate or aerosol form comprising the steps of:

providing a substrate having an open architecture, said surface including chemical patterning on one or more portions of said surface to form one or more surface pathways;

selectively activating said heat source;

applying a liquid to said substrate and allowing said liquid to flow by thermocapillary shear stresses through activation of said heating source;

applying said airborne material to said substrate; and

detecting said airborne material in said liquid,

wherein said chemical patterning confines said liquid in said one or more surface pathways and said activated heat source provides selective movement of said liquid along said one or more surface pathways in a predetermined flow path.

8. The method of claim 7 wherein said heat source is positioned in registry with one or more source said reservoirs.

9. The method of claim 7 wherein said heat source comprises one or more heating elements.

10. The method of claim 7 wherein said airborne material is detected by liquid by becoming fluorescent.

11. The method of claim 7 wherein said airborne material is applied by a convective stream of said airborne material perpendicular to said one or more pathways.

12. A device for routing a liquid comprising:

a surface having an open architecture, said surface including chemical patterning on one or more portions of said surface to form one or more surface pathways;

heating elements in registry with said surface; and

means for selectively activating said heating elements

wherein said chemical patterning confines said liquid in said one or more surface pathways and said activated heating elements provide selective movement of said liquid along said one or more surface pathways by thermocapillary shear stresses in a predetermined flow path.

13. The device of claim 12 wherein each of said one or more surface pathways connect a source reservoir to a target reservoir.

14. The device of claim 12 further comprising a plurality of said surface pathways, each of said surface pathways connect a source reservoir to a target reservoir.

15. The device of claim 12 wherein a plurality of said pathways form a network including a first plurality of said surface pathways each having a source reservoir and a target reservoir and a second plurality of said surface pathways each having a source reservoir and a target reservoir, said first plurality of said surface pathways being interconnected to said second plurality of said surface pathways.

16. The device of claim 12 further comprising a plurality of first surface pathways connected perpendicularly to a second surface pathway, each of said first surface pathways and said second surface pathway having a source reservoir and a target reservoir.

17. The device of claim 12 wherein a plurality of said surface pathways are arranged radially from a source reservoir to a plurality of target reservoirs or from a plurality of source reservoirs to a target reservoir.

18. The device of claim 12 wherein said one or more surface pathways are rectilinear.

19. The device of claim 12 wherein said one or more surface pathways are curvilinear.

20. The device of claim 12 wherein said one or more surface pathways are sinuous.

21. The device of claim 12 wherein each of said one or more heating elements are associated with a cell, said cell including at least one transistor, said transistor being activated for activating said heating element of said cell.

22. The device of claim 12 wherein said cells are arranged in a matrix array.

23. The device of claim 12 wherein each of said surface pathways connects a source reservoir to a target reservoir and one said heating element is used for heating or cooling said source reservoir.

24. The device of claim 12 wherein said surface is formed on a substrate and said one or more heating elements are associated in registry with said substrate.

25. The device of claim 24 wherein a thermal insulation layer is coupled to an upper surface of said substrate and a bottom surface of said heating elements.

26. The device of claim 24 wherein an electrical insulation layer is coupled to an upper surface of said substrate and a bottom surface of said heating elements.

27. The device of claim 24 wherein an electrical insulation layer is coupled to an upper surface of said heating elements.

28. The device of claim 24 further comprising a passivation layer coupled to said substrate.

29. The device of claim 24 further comprising a planarization layer coupled to said one or more heating elements.

30. The device of claim 24 wherein said one or more heating elements are coupled to a first region of said substrate and a heat sink is coupled to a second region of said substrate.

31. The device of claim 24 wherein said activated one or more heating elements form a thermal map.

32. The device of claim 31 wherein said liquid is a continuous stream and activation of said thermal map divides said stream into an array of droplets.

33. The device of claim 32 wherein said droplets have equal size or unequal size.

34. The device of claim 31 wherein said liquid is one or more droplets and activation of said thermal map traps said one or more droplets.

35. The device of claim 34 wherein application of a second thermal map releases said trapped one or more droplets.

36. The device of claim 31 wherein activation of said thermal map initiates a reaction at one or more of said heating elements.

37. The device of claim 31 wherein activation of said thermal map quenches a reaction at said one or more heating elements.

38. The device of claim 12 wherein said chemical patterning comprises one or more hydrophobic portions confining a hydrophilic surface, said hydrophilic surface defining said one or more pathways wherein said liquid flows along said hydrophilic surface.

39. The device of claim 12 wherein a first said liquid is received in one of said surface pathways and a second said liquid is received in another of said surface pathways, said surface pathways being interconnected wherein flow of said liquid in said surface pathways mixes said first said liquid and said second said liquid.

40. The device of claim 39 wherein first said one or more heating elements apply a thermal gradient transverse to said surface pathways.

41. The device of claim 39 wherein second said one or more heating elements apply a thermal gradient parallel to said surface pathway.

42. The device of claim 12 wherein an airborne material in gaseous, particulate or aerosol form is absorbed in said liquid and further comprising:

means for detecting said absorbed material.

43. The device of claim 42 wherein said material is detected by fluorescence of said liquid upon contact with said material.

44. The device of claim 12 wherein said surface including chemical patterning has a flat topology.

45. The device of claim 12 further comprising one or more ridges in said surface including chemical patterning and said one or more surface pathways being defined respectively along said one or more ridges.

46. The device of claim 12 further comprising one or more indentations in said surface including chemical patterning, said one or more surface pathways being defined along said one or more indentations.

47. The device of claim 12 further comprising one or more grooves in said surface including chemical patterning said one or more surface pathways being defined respectively along said more grooves.

48. A method for routing a liquid comprising the steps of:

providing a surface having an open architecture, said surface including chemical patterning on one or more portions of said surface to form one or more surface pathways;

providing one or more heating elements in registry with said surface;

receiving said liquid on said surface; and

selectively activating said heating elements

wherein said chemical patterning confines said liquid in said one or more surface pathways and said activated heating elements by thermocapillary shear stresses provide selective movement of said liquid along said one or more surface pathways in a predetermined flow path.

49. The method of claim 48 wherein each of said one or more surface pathways connect a source reservoir to a target reservoir.

50. The method of claim 48 comprising a plurality of said surface pathways, each of said pathways connect a source reservoir to a target reservoir.

51. The method of claim 48 wherein a plurality of said surface pathways form a network including a first plurality of said surface pathways each having a source reservoir and a target reservoir and a second plurality of said surface pathways each having a source reservoir and a target reservoir, said first plurality of surface pathways being interconnected to said second plurality of surface pathways.

52. The method of claim 48 further comprising a plurality of first said surface pathways connected perpendicularly to a second surface pathway, each of said first surface pathways and said second surface pathway having a source reservoir and a target reservoir.

53. The method of claim 48 wherein a plurality of said surface pathways are arranged radially from a source reservoir to a plurality of target reservoirs or radially from a plurality of source reservoirs to a target reservoir.

54. The method of claim 48 wherein said one or more surface pathways are rectilinear.

55. The method of claim 48 wherein said one or more surface pathways are curvilinear.

56. The method of claim 48 wherein said one or more surface pathways are sinuous.

57. The method of claim 48 wherein each of said heating elements are associated with a cell, said cell including at least one transistor, said transistor being activated for activating said heating element of said cell.

58. The method of claim 57 wherein said cells are arranged in a matrix array.

59. The method of claim 57 wherein each of said one or more surface pathways connects a source reservoir to a target reservoir and one said heating elements is used for heating or cooling said source reservoir.

60. The method of claim 48 wherein said surface is formed on a substrate and said heating elements are associated in registry with said substrate.

61. The method of claim 60 wherein a thermal insulation layer is coupled to an upper surface of said substrate and a bottom surface of said one or more heating elements.

62. The method of claim 60 wherein an electrical insulation layer is coupled to an upper surface of said substrate and a bottom surface of said one or more heating elements.

63. The method of claim 60 wherein an electrical insulation layer is coupled to an upper surface of said one or more heating elements.

64. The method of claim 60 further comprising a passivation layer coupled to said substrate.

65. The method of claim 60 further comprising a planarization layer coupled to said one or more heating elements.

66. The method of claim 60 wherein said one or more heating elements are coupled to a first region of said substrate and a heat sink is coupled to a second region of said substrate.

67. The method of claim 48 wherein said activated one or more heating elements form a thermal map.

68. The method of claim 67 wherein said liquid is a continuous stream and activation of said thermal map divides said stream into a series of droplets.

69. The method of claim 68 wherein said droplets have equal size or unequal size.

70. The method of claim 67 wherein said liquid is one or more droplets and activation of a first said thermal map traps said one or more droplets.

71. The method of claim 67 wherein application of a second thermal map releases said trapped one or more droplets.

72. The method of claim 67 wherein activation of said thermal map initiates a reaction.

73. The method of claim 67 wherein activation of said thermal map quenches a reaction.

74. The method of claim 48 wherein said chemical patterning comprises one or more hydrophobic portions confining a hydrophilic surface, said hydrophilic surface defining said one or more pathways wherein said liquid flows along said hydrophilic surface.

75. The method of claim 48 wherein a first said liquid is received in one of said surface pathways and a second said liquid is received in another of said surface pathways, said surface pathways being interconnected, wherein flow of said liquid in said surface pathways mixes said first said liquid and said second said liquid.

76. The method of claim 75 wherein first said one or more heating elements apply a thermal gradient transverse to said surface pathways.

77. The method of claim 75 wherein second said one or more heating elements apply a thermal gradient parallel to said surface pathways.

78. The method of claim 48 wherein an airborne material in gaseous, particulate or aerosol form is absorbed in said liquid and further comprising the step of:

detecting said absorbed material.

79. The method of claim 78 wherein said material is detected by fluorescence of said liquid upon contact with said material.

80. The method of claim 48 further comprising the step of:

storing said surface in glycerol.

81. The method of claim 48 further comprising the step of:

applying a layer of glycerol on said surface.

82. The method of claim 74 further comprising the step of

applying a layer of glycerol on said hydrophilic surface.

83. The method of claim 48 wherein said surface including chemical patterning has a flat topology.

84. The method of claim 48 further comprising one or more ridges in said surface including chemical patterning and said one or more surface pathways being defined respectively along said one or more ridges.

85. The method of claim 48 further comprising one or more indentations in said surface including chemical patterning, said one or more surface pathways being defined along said one or more indentations.

86. The method of claim 48 further comprising one or more grooves in said surface including chemical patterning said one or more surface pathways being defined respectively along said more grooves.

87. A device for detecting an airborne material in gaseous, particulate or aerosol form comprising:

a surface having an open architecture, said surface including chemical patterning on one or more portions of said surface to form one or more surface pathways;

applying a liquid to said substrate and allowing said liquid to flow by activation of said heating source;

selectively activating said heat source, wherein said chemical patterning confines said liquid in said one or more surface pathways and said activated heat source provides selective movement of said liquid along said one or more surface pathways by thermocapillary shear stresses in a predetermined flow path;

means for applying said airborne material to said network; and

means for detecting said airborne material in said liquid.

90. The device of claim 87 wherein said heat source is positioned in registry with one or more source said reservoirs.

91. The device of claim 87 wherein said heat source comprises one or more heating elements.

92. The device of claim 87 wherein said airborne material is detected by liquid by becoming fluorescent.

93. The device of claim 87 wherein said airborne material is applied by a convective stream of said airborne material perpendicular to one or more said surface pathways.

88. A method for storing a device, said device comprising a device for detecting an airborne material in gaseous, particulate or aerosol form including a substrate having a network of one or more surface pathways on an upper surface of said substrate, said substrate having an open architecture, said substrate including chemical patterning on one or more portions of said surface to form one or more surface pathways, one or more heating elements in registry with said surface;

comprising the step of;

storing said device in glycerol.

89. A method for storing a device, said device comprising a device for detecting an airborne material in gaseous, particulate or aerosol form including a substrate having a network of one or more surface pathways on an upper surface of said substrate, said substrate having an open architecture, said substrate including chemical patterning on one or more portions of said surface to form one or more surface pathways, one or more heating elements in registry with said surface;

comprising the steps of;

applying a layer of glycerol on said patterned surface.