Microfluidic Devices and Methods for Fabricating the Same

• US 20090004737A1
• Filed: 11/21/2007
• Published: 01/01/2009
• Est. Priority Date: 11/21/2006
• Status: Active Grant

• Current Assignee: Charles Stark Draper Laboratory Incorporated, Trustees of Tufts College
• Original Assignee: Trustees of Tufts College
• Inventors: Bettinger, Chris, Borenstein, Jeffrey T., Kaplan, David
• Granted Patent: US 8,975,073 B2
• Time in Patent Office: Days
• US Class Current: 435/395
• CPC Class Codes: B01L 2200/12 Specific details about manufacturing devices
• CPC Class Codes: B01L 2300/163 Biocompatibility
• 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: B81B 2201/058 Microfluidics not provided for in B81B2201/051 - B81B2201/054
• CPC Class Codes: B81C 99/0085 using moulds and master templates, e.g. for hot-embossing
• CPC Class Codes: C12M 23/16 Microfluidic devices; Capillary tubes integrated microfluidic structures B01L3/5027; microreactors B01J19/0093
• CPC Class Codes: C12M 23/20 Material Coatings immunocoatings C12M25/00
• CPC Class Codes: C12M 25/02 Membranes; Filters filters or filtration in general B01D24/00-B01D41/00
• CPC Class Codes: C12M 29/10 Perfusion
• CPC Class Codes: Y10T 137/0324 With control of flow by a condition or characteristic of a fluid

Abstract

A microfluidic device includes, in one embodiment, a first silk film coupled to a second silk film with at least one microchannel therebetween.

Claims

1. A microfluidic device, comprising first and second silk film coupled to define at least one microchannel therebetween.

2. The microfluidic device of claim 1, wherein at least one of the first and second silk films comprises silk fibroin.

3. The microfluidic device of claim 1, wherein the microchannel is molded into the first fibroin film.

4. The microfluidic device of claim 1, wherein at least a portion of the first silk film and at least a portion of the second silk film are bonded together.

5. The microfluidic device of claim 3, wherein an interface between the first and second silk films is water insoluble.

6. The microfluidic device of claim 1, wherein the microchannel is enclosed.

7. The microfluidic device of claim 1, wherein a portion of a surface of the microchannel supports cell growth.

8. The microfluidic device of claim 7, wherein the portion of the surface of the microchannel supports the growth of cells in their native morphology.

9. The microfluidic device of claim 7, wherein eukaryotic cell growth is supported.

10. The microfluidic device of claim 7, wherein hepatocyte cell growth is supported.

11. The microfluidic device of claim 1, wherein the first and second silk fibroin films define a plurality of microchannels therebetween.

12. The microfluidic device of claim 11, wherein each microchannel has a diameter less than 500 micrometers.

13. The microfluidic device of claim 11, wherein at least a portion of the plurality of microchannels are in fluidic communication.

14. The microfluidic device of claim 11, wherein at least a portion of the plurality of microchannels repeat a geometric pattern.

15. The microfluidic device of claim 14, wherein the repeated geometric pattern provides for a constant maximum shear stress at a steady volumetric flow rate within all the microchannels.

16. A microdevice for use in growing cells, comprising:

a silk layer having a plurality of molded microfeatures formed therein or thereon, each of the molded microfeatures being less than 500 micrometers in diameter,

wherein the plurality of molded microfeatures delineate regions on the silk layer supporting cell growth.

17. The microdevice of claim 16, wherein the microfeatures comprise at least one of a microchannel, a post, a microwall, or a raised platform.

18. The microdevice of claim 16, wherein the microdevice is biodegradable.

23. The method of claim 18, wherein the additional layer comprises silk fibroin.

19. A method for fabricating a microfluidic device, the method comprising:

applying a silk solution to a negative mold;

evaporating solvent from the solution to form a micromolded silk film;

removing the micromolded silk film from the negative mold; and

laminating the micromolded silk film to at least one additional layer to form a microfluidic device having at least one enclosed microchannel.

20. The method of claim 19, wherein the silk solution is an aqueous solution.

21. The method of claim 19, wherein the negative mold imparts a plurality of microchannels into the micromolded silk fibroin film.

22. The method of claim 21, wherein each microchannel is less than 500 micrometers in diameter.

24. A method for transporting fluid, comprising:

providing a microfluidic device having a microchannel formed in a silk film, the microchannel comprising an inlet and an outlet; and

transporting fluid along the microchannel from the inlet to the outlet.

25. A method for growing cells, comprising:

providing a microfluidic device having a microchannel formed in a silk film;

flowing cell culture medium through the microchannel; and

seeding cells into the microchannel to allow the cells to adhere to a surface of the microchannel.