Multi-stream microfluidic aperture mixers

• US 20030133358A1
• Filed: 05/03/2002
• Published: 07/17/2003
• Est. Priority Date: 01/11/2002
• Status: Active Grant

• Current Assignee: Agilent Technologies, Inc.
• Original Assignee: Nanostream, Inc.
• Inventors: Karp, Christoph D.
• Granted Patent: US 6,877,892 B2
• Time in Patent Office: Days
• US Class Current: 366/341
• CPC Class Codes: B01F 25/314 wherein additional components are introduced at the circumference of the conduit
• CPC Class Codes: B01F 25/422 between stacked plates, e.g. grooved or perforated plates
• CPC Class Codes: B01F 25/433 Mixing tubes wherein the shape of the tube influences the mixing, e.g. mixing tubes with varying cross-section or provided with inwardly extending profiles
• CPC Class Codes: B01F 33/30 Micromixers
• CPC Class Codes: Y10S 366/04 Micromixers: with application of energy to influence mixing/agitation, e.g. magnetic, electrical, e-m radiation, particulate radiation, or ultrasound

Abstract

Robust microfluidic mixing devices mix multiple fluid streams passively, without the use of moving parts. In one embodiment, these devices contain microfluidic channels that are formed in various layers of a three-dimensional structure. Mixing may be accomplished with various manipulations of fluid flow paths and/or contacts between fluid streams. In various embodiments, structures such as channel overlaps, slits, converging/diverging regions, turns, and/or apertures may be designed into a mixing device. Mixing devices may be rapidly constructed and prototyped using a stencil construction method in which channels are cut through the entire thickness of a material layer, although other construction methods including surface micromachining techniques may be used.

Claims

1. A microfluidic device for mixing a plurality of fluid streams, the mixing device comprising:

a plurality of microfluidic inlet channels that merge into a microfluidic junction channel, the junction channel being defined in a first device layer and having a characteristic cross-sectional area; and

a plurality of contraction/expansion regions in fluid communication with the junction channel and arranged in series, each contraction/expansion region including;

an aperture defined in a second device layer, the aperture having a characteristic cross-sectional area that is substantially smaller than the area of the junction channel; and

a microfluidic expansion channel defined in either the first device layer or a third device layer, the expansion channel having a characteristic cross-sectional area that is substantially larger than the area of the aperture.

2. The microfluidic mixing device of claim 1 wherein each aperture is less than about two hundred fifty microns in major dimension.

3. The microfluidic mixing device of claim 2 wherein:

the junction channel contains a stream of multiple fluids;

upstream of an aperture, the stream of multiple fluids flows in substantially a first direction;

downstream of an aperture, the stream of multiple fluids flows in substantially a second direction that is substantially different from the first direction.

4. The microfluidic mixing device of claim 3 wherein the second direction is at least about ninety degrees apart from the first direction.

5. The microfluidic mixing device of claim 1 wherein at least one device layer comprises a stencil layer, and any of the inlet channels, junction channel, and expansion channel are defined through the entire thickness of a stencil layer.

6. The microfluidic mixing device of claim 1 wherein any of the inlet channels, junction channel, and expansion channel are defined in a surface but do not penetrate the entire thickness of a device layer.

7. The microfluidic mixing device of claim 6 wherein any of the inlet channels, junction channel, and expansion channel are defined using one or more surface micromachining techniques.

8. The microfluidic mixing device of claim 1 wherein the device is formed with a plurality of device layers, and the various device layers are bonded or fastened together.

9. The microfluidic mixing device of claim 8 wherein the bonded or fastened layers form a substantially sealed device.

10. A microfluidic mixing device comprising:

a first device layer defining two fluid input channels and a junction, the fluid channels each having a characteristic width and converging at the junction;

a second device layer defining a first fluid output channel, the first fluid output channel having a characteristic width, with a portion of the first fluid output channel overlapping the junction at a first channel overlap region; and

a spacer layer disposed between the first device layer and the second device layer, the spacer layer defining a first aperture positioned at the first channel overlap region;

wherein the first aperture has a major dimension that is substantially smaller than the width of each of the fluid input channels and the first fluid output channel.

11. The microfluidic mixing device of claim 10 wherein the width of each of the fluid input channels and the first fluid output channel is between about one thousand microns and about three thousand microns.

12. The microfluidic mixing device of claim 10 wherein the major dimension of the aperture is between about one hundred fifty microns and about two hundred fifty microns.

13. The microfluidic mixing device of claim 10 wherein:

the first device layer defines a second output channel having a characteristic width, with a portion of the second output channel overlapping a portion of the first output channel at a second channel overlap region; and

the spacer layer defines a second aperture positioned at the second channel overlap region;

wherein the second aperture has a major dimension that is substantially smaller than the width of each of the first fluid output channel and the second fluid output channel.

14. The microfluidic mixing device of claim 13, further comprising a plurality of directional change regions associated with the first channel overlap region and the second channel overlap region.

15. The microfluidic mixing device of claim 10 wherein at least one of the first device layer and the second device layer comprises a stencil layer, and any of the fluid input channels and the first fluid output channel is defined through the entire thickness of a stencil layer.

16. The microfluidic mixing device of claim 10 wherein any of the first fluid output channel and the fluid input channels are defined in a surface but do not penetrate the entire thickness of a device layer.

17. The microfluidic mixing device of claim 16 wherein any of the first fluid output channel and the fluid input channels are defined using one or more surface micromachining techniques.

18. The microfluidic mixing device of claim 10 wherein at least one of the first device layer, the second device layer, and the spacer layer is fabricated with a polymeric material.

19. The multi-layer microfluidic splitting device of claim 10 wherein at least one of the first device layer, the second device layer, and the spacer layer is fabricated with self-adhesive tape.

20. A microfluidic mixing device comprising:

a first device layer defining a first channel having an outlet, the first channel having a height dimension and a width dimension;

a mixing layer defining a contraction/expansion region in fluid communication with the outlet;

a second device layer defining a second channel having an inlet in fluid communication with the contraction/expansion region, the second channel having a height dimension and a width dimension;

wherein the contraction/expansion region includes at least one aperture having a major dimension, the aperture being substantially smaller in major dimension than at least one dimension of the first channel and substantially smaller than at least one dimension of the second channel.

21. The microfluidic mixing device of claim 20 wherein the contraction/expansion region includes a plurality of apertures, each aperture of the plurality of apertures having a major dimension substantially smaller than at least one dimension of the first channel and substantially smaller than at least one dimension of the second channel.

22. The microfluidic mixing device of claim 21, further comprising a plurality of directional change regions fluidically disposed between the first channel and the second channel.

23. The microfluidic mixing device of claim 20 wherein at least one dimension of each of the first channel and the second channel is between about one micron and about five hundred microns.

24. The microfluidic mixing device of claim 23 wherein a ratio of the width dimension to the height dimension of each of the first channel and the second channel is between about two and about ten.

25. The microfluidic mixing device of claim 20 wherein at least one dimension of each of the first channel and the second channel is between about ten microns and about one hundred microns.

26. The microfluidic mixing device of claim 25 wherein a ratio of the width dimension to the height dimension of each of the first channel and the second channel is between about two and about ten.

27. The microfluidic mixing device of claim 20 wherein the major dimension of the aperture is between about one hundred fifty microns and about two hundred fifty microns.

28. The microfluidic mixing device of claim 20 wherein at least one of the first device layer and the second device layer comprises a stencil layer, and any of the first channel and the second channel are defined through the entire thickness of a stencil layer.

29. The microfluidic mixing device of claim 20 wherein any of the first channel and the second channel are defined in a surface but do not penetrate the entire thickness of a device layer.

30. The microfluidic mixing device of claim 20 wherein any of the first channel and the second channel are defined using one or more surface micromachining techniques.

31. The microfluidic mixing device of claim 20 wherein at least one of the first device layer, the second device layer, and the mixing layer is fabricated with a polymeric material.

32. The multi-layer microfluidic splitting device of claim 20 wherein at least one of the first device layer, the second device layer, and the mixing layer is fabricated with self-adhesive tape.

33. A microfluidic mixing device comprising:

a first stencil layer defining a first channel having an outlet;

a means for mixing fluids in fluid communication with the outlet;

a second stencil layer defining a second channel having an inlet in fluid communication with the mixing means;

wherein the mixing means includes at least one aperture having a major dimension, the aperture being substantially smaller in major dimension than a major dimension of the first channel and substantially smaller in major dimension than a major dimension of the second channel.

34. The multi-layer microfluidic splitting device of claim 33 wherein the mixing means comprises a plurality of apertures wherein each aperture of the plurality of apertures has a major dimension that is substantially smaller than a major dimension of the first channel and a substantially smaller than a major dimension of the second channel.

35. The microfluidic mixing device of claim 34, further comprising a plurality of directional change regions fluidically disposed between the first channel and the second channel.

36. The microfluidic mixing device of claim 33 wherein:

the first channel has a height dimension and a width dimension;

the second channel has a height dimension and a width dimension; and

the height dimension of each of the first channel and the second channel is between about one micron and about five hundred microns.

37. The microfluidic mixing device of claim 36 wherein a ratio of the width dimension to the height dimension of each of the first channel and the second channel is between about two and about ten.

38. The microfluidic mixing device of claim 33 wherein

the first channel has a height dimension and a width dimension;

the second channel has a height dimension and a width dimension; and

the height dimension of each of the first channel and the second channel is between about ten microns and about one hundred microns.

39. The microfluidic mixing device of claim 38 wherein a ratio of the width dimension to the height dimension of each of the first channel and the second channel is between about two and about ten.

40. The microfluidic mixing device of claim 33 wherein the width of each of the fluid input channels and the first fluid output channel is between about one thousand microns and about three thousand microns.

41. The microfluidic mixing device of claim 33 wherein the major dimension of the aperture is between about one hundred and fifty microns and about two hundred and fifty microns.

42. The microfluidic mixing device of claim 33 wherein at least one of the first stencil layer, the second stencil layer, and the mixing means is fabricated with a polymeric material.

43. The microfluidic splitting device of claim 33 wherein at least one of the first stencil layer, the second stencil layer, and the mixing means is fabricated with self-adhesive tape.