Microfluidic Device Facilitating Gas Exchange, and Methods of Use and Manufacture Thereof

• US 20110158847A1
• Filed: 12/30/2010
• Published: 06/30/2011
• Est. Priority Date: 12/31/2009
• Status: Active Grant

• Current Assignee: Charles Stark Draper Laboratory Incorporated
• Original Assignee: Charles Stark Draper Laboratory Incorporated
• Inventors: Charest, Joseph L., Bauer, Joseph M., Borenstein, Jeffrey T.
• Granted Patent: US 9,067,179 B2
• Time in Patent Office: Days
• US Class Current: 422/45
• CPC Class Codes: A61M 1/14 Dialysis systems; Artificial kidneys; Blood oxygenators semi-permeable membranes characterised by the material, manufacturing processes therefor B01D71/00; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/1698 Blood oxygenators with or without heat-exchangers intracorporal A61M1/1678; manufacturing of membranes therefor B01D67/00; semi-permeable membranes for separation processes characterised by their properties B01D69/00; semi-permeable membranes characterised by their material B01D71/00
• CPC Class Codes: A61M 2205/0244 Micromachined materials, e.g. made from silicon wafers, microelectromechanical systems [MEMS] or comprising nanotechnology
• CPC Class Codes: A61M 2206/11 Laminar flow
• CPC Class Codes: B01D 2325/04 Characteristic thickness
• CPC Class Codes: B01D 63/081 Manufacturing thereof
• CPC Class Codes: B01D 63/082 comprising a stack of flat membranes
• CPC Class Codes: B01D 63/085 specially adapted for two fluids in mass exchange flow
• CPC Class Codes: B01D 63/088 Microfluidic devices comprising semi-permeable flat membranes
• CPC Class Codes: B01D 67/0009 by phase separation, sol-gel transition, evaporation or solvent quenching
• CPC Class Codes: B01D 69/02 characterised by their properties
• CPC Class Codes: B01D 69/06 Flat membranes
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

The invention provides systems and methods for exchanging gas in a microfluidic device, and methods for preparing such microfluidic devices. The systems and methods can be used to transfer oxygen to blood to assist lung function in a patient.

Claims

1. A microfluidic device, comprising:

a first layer of a single type of gas permeable material that defines therein at least one chamber for gas flow and at least one chamber for fluid flow, wherein the thickness of gas permeable material separating any chamber for gas flow from an adjacent chamber for fluid flow is about 1 μ

m to about 100 μ

m.

3. The microfluidic device of claim 1, wherein the first layer defines therein a plurality of chambers for gas flow and a plurality of chambers for fluid flow, and the thickness of gas permeable material separating any chamber for gas flow from an adjacent chamber for fluid flow is about 1 μ

m to about 100 μ

m.

4. The microfluidic device of claim 1, wherein any chamber for gas flow and any chamber for fluid flow are arranged such that flow directions for the gas and the fluid are parallel or anti-parallel to one another.

5. The microfluidic device of claim 1, wherein each chamber for fluid flow is located between two chambers for gas flow.

6. The microfluidic device of claim 1, wherein at least one chamber for gas flow is arranged such that the flow direction of gas is transverse to the direction of fluid flow in the chamber for fluid flow.

7. The microfluidic device of claim 1, further comprising a second layer of a single type of gas permeable material stacked upon the first layer, where the second layer defines therein at least one chamber for gas flow and at least one chamber for fluid flow.

8. The microfluidic device of claim 7, further comprising a third layer of a single type of gas permeable material stacked upon the second layer, where the third layer defines therein at least one chamber for gas flow and at least one chamber for fluid flow.

9. The microfluidic device of claim 7, wherein the thickness of the gas permeable material separating a chamber for gas flow in the second layer from a chamber for fluid flow in the second layer is about 1 μ

m to about 100 μ

m.

10. The microfluidic device of claim 1, wherein any chambers for fluid flow in a layer are positioned between two chambers for gas flow in the same layer, and said chambers for fluid flow are aligned vertically with a chamber for gas flow in any adjacent layer.

11. The microfluidic device of claim 1, wherein the thickness of gas permeable material separating any chamber for gas flow in the microfluidic device from a chamber for fluid flow in the microfluidic device is about 10 μ

m to about 100 μ

m.

12. The microfluidic device of claim 1, wherein the thickness of gas permeable material separating any chamber for gas flow in a layer from a chamber for fluid flow in the same layer is about 50 μ

m to about 100 μ

m.

13. The microfluidic device of claim 1, wherein the thickness of gas permeable material separating any chamber for gas flow in the microfluidic device from a chamber for fluid flow in the microfluidic device is about 10 μ

m to about 25 μ

m.

14. The microfluidic device of claim 1, further comprising a distribution system for delivering gas to any gas chamber in the device, and delivering fluid to any fluid chamber in the device.

15. The microfluidic device of claim 14, wherein the system comprises branching or bifurcating microchannels, biomimetic vascular-like channels, or a manifold structure.

16. The microfluidic device of claim 1, wherein any fluid chamber has a height less than 25 μ

m.

17. The microfluidic device of claim 1, wherein any fluid chamber has a height of about 10 μ

m to about 15 μ

m.

18. The microfluidic device of claim 1, wherein any fluid chamber has a width of less than 200 μ

m.

19. The microfluidic device of claim 1, wherein the fluid chamber has a width to height ratio of at least 2 to 1.

20. The microfluidic device of claim 1, wherein any chamber for fluid flow has a cross-section that is semi-circular.

21. The microfluidic device of claim 1, wherein any chamber for fluid flow is coated with an anti-coagulant.

22. The microfluidic device of claim 1, wherein the gas permeable material is an organosilicone polymer, polyethylene, or polyurethane.

23. The microfluidic device of claim 1, wherein the gas permeable material is polydimethylsiloxane.

24. The microfluidic device of claim 1, wherein the chamber for fluid flow comprises blood, and the chamber for gas flow comprises oxygen.

25. A method for transferring a gas to a fluid, comprising passing a fluid through a microfluidic device of claim 1 having a gas in at least one chamber for gas flow, to thereby transfer said gas to said fluid.

26. The method of claim 25, wherein said fluid is blood, and said gas comprises oxygen.

27. The method of claim 26, wherein the microfluidic device is fluidly connected to the blood vasculature of a patient.

28. The method of claim 25, further comprising transferring a gas dissolved in said fluid to a chamber for gas flow in the microfluidic device.

2. A microfluidic device, comprising:

a first layer of a single type of gas permeable material that defines therein at least one chamber for gas flow and at least one chamber for fluid flow, wherein the thickness of gas permeable material separating any chamber for gas flow from an adjacent chamber for fluid flow is no greater than that which has an oxygen gas permeance of at least 1×

10<sup>−

6</sup> mL/s/cm²/cm Hg.

29. A method of manufacturing a microfluidic device, comprising:

forming a first layer of a single type of gas permeable material that defines therein at least one chamber for gas flow and at least one chamber for fluid flow, wherein the thickness of gas permeable material separating any chamber for gas flow from an adjacent chamber for fluid flow is about 1 μ

m to about 100 μ

m.

30. The method of claim 29, wherein the thickness of gas permeable material separating any chamber for gas flow from an adjacent chamber for fluid flow is about 10 μ

m to about 100 μ

m

31. The method of claim 29, further comprising forming at least one chamber for gas flow and at least one chamber for fluid flow in at least one additional layer of a single type of gas permeable material.

32. The method of claim 29, further comprising coupling additional layers of the single type of gas permeable material to the first layer.

33. The method of claim 31, wherein the layers of gas permeable material are stacked.