Laminated microfluidic structures and method for making

• US 20060078470A1
• Filed: 10/13/2004
• Published: 04/13/2006
• Est. Priority Date: 10/13/2004
• Status: Active Grant

• Current Assignee: Rheonix, Inc.
• Original Assignee: Kionix Incorporated (ROHM Co., Ltd.)
• Inventors: Young, Lincoln C., Zhou, Peng
• Granted Patent: US 7,608,160 B2
• Time in Patent Office: Days
• US Class Current: 422/100
• CPC Class Codes: B01F 25/451 characterised by means for moving the materials to be mixed or the mixture
• CPC Class Codes: B01F 25/4521 the components being pressed through orifices in elements, e.g. flat plates or cylinders, which obstruct the whole diameter of the tube
• CPC Class Codes: B01F 31/65 the materials to be mixed being directly submitted to a pulsating movement, e.g. by means of an oscillating piston or air column
• CPC Class Codes: B01F 33/30 Micromixers
• CPC Class Codes: B01L 2200/12 Specific details about manufacturing devices
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2300/0861 Configuration of multiple channels and/or chambers in a single devices
• CPC Class Codes: B01L 2300/0867 Multiple inlets and one sample wells, e.g. mixing, dilution
• CPC Class Codes: B01L 2300/0887 Laminated structure
• CPC Class Codes: B01L 2400/0481 squeezing of channels or chambers
• CPC Class Codes: B01L 2400/0655 pinch valves
• CPC Class Codes: B01L 2400/084 Passive control of flow resistance
• 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: B29C 65/4895 Solvent bonding, i.e. the surfaces of the parts to be joined being treated with solvents, swelling or softening agents, without adhesives
• CPC Class Codes: B29C 66/1122 Single lap to lap joints, i.e. overlap joints B29C66/45, B29C66/472, B29C66/52272 take precedence
• CPC Class Codes: B29C 66/54 Joining several hollow-preforms, e.g. half-shells, to form hollow articles, e.g. for making balls, containers; Joining several hollow-preforms, e.g. half-cylinders, to form tubular articles
• CPC Class Codes: B29C 66/543 joining more than two hollow-preforms to form said hollow articles
• CPC Class Codes: B29C 66/71 characterised by the composition of the plastics material of the parts to be joined welding bar compositions B29C65/125
• CPC Class Codes: B29C 66/83411 Roller, cylinder or drum types B29C66/83431 takes precedence; rollers, cylinders or drums moving relative to and tangentially to the parts to be joined B29C66/8362
• CPC Class Codes: B29C 66/8362 Rollers, cylinders or drums moving relative to and tangentially to the parts to be joined
• CPC Class Codes: B29K 2025/06 : PS, i.e. polystyrene
• CPC Class Codes: B29K 2033/08 : Polymers of acrylic acid esters, e.g. PMA, i.e. polymethylacrylate
• CPC Class Codes: B29K 2069/00 : Use of PC, i.e. polycarbonates or derivatives thereof, as moulding material
• CPC Class Codes: B29L 2031/756 : Microarticles, nanoarticles
• CPC Class Codes: B32B 37/0038 : involving application of liquid to the layers prior to lamination, e.g. wet laminating B32B37/12 takes precedence
• CPC Class Codes: F04B 43/06 : Pumps having fluid drive
• CPC Class Codes: F16K 2099/0074 : using photolithography, e.g. etching
• CPC Class Codes: F16K 2099/0078 : using moulding or stamping
• CPC Class Codes: F16K 2099/0084 : Chemistry or biology, e.g. "lab-on-a-chip" technology
• CPC Class Codes: F16K 2099/0094 : Micropumps
• CPC Class Codes: F16K 99/0001 : Microvalves microdevices B81B1/00; manufacture or treatment of devices or systems in or on a substrate B81C1/00; microfluidic structures B01L3/5027; micropumps F04B19/006
• CPC Class Codes: F16K 99/0015 : Diaphragm or membrane valves
• CPC Class Codes: F16K 99/0021 : No-moving-parts valves
• CPC Class Codes: F16K 99/0034 : Operating means specially adapted for microvalves
• CPC Class Codes: F16K 99/0055 : actuated by fluids
• CPC Class Codes: F16K 99/0057 : the fluid being the circulating fluid itself, e.g. check valves
• CPC Class Codes: Y10T 156/1002 : with permanent bending or reshaping or surface deformation of self sustaining lamina

Abstract

A method for making a polymeric microfluidic structure in which two or more components (layers) of the microfluidic structure are fixedly bonded or laminated with a weak solvent bonding agent, particularly acetonitrile or a mixture of acetonitrile and alcohol. In an aspect, acetonitrile can be used as a weak solvent bonding agent to enclose a microstructure fabricated in or on a non-elastomeric polymer such as polystyrene, polycarbonate, acrylic or other linear polymer to form a three-dimensional microfluidic network. The method involves the steps of wetting at least one of the opposing surfaces of the polymeric substrate components with the weak solvent bonding agent in a given, lower temperature range, adjacently contacting the opposing surfaces, and thermally activating the bonding agent at a higher temperature than the lower temperature range for a given period of time. The contacted polymeric substrates may also be aligned prior to thermal activation and compressed during thermal activation. A laminated, polymeric microfluidic structure is also disclosed.

Claims

1. A laminated microfluidic structure, comprising:

a first component having first and second surfaces, wherein at least one of the surfaces includes a microstructure, further wherein the first component is a polymeric material; and

a second, polymeric component having first and second surfaces, wherein one of the first and second surface of the second component is fixedly attached to one of the second and first surface of the first component, respectively, by a bonding agent, wherein the bonding agent is a weak solvent with respect to the polymeric components.

2. The microfluidic structure of claim 1, wherein the bonding agent is acetonitrile.

3. The microfluidic structure of claim 1, wherein the bonding agent is a mixture of acetonitrile and an inert solvent.

4. The microfluidic structure of claim 1, wherein the polymeric components include at least one of a polystyrene material, a polycarbonate material, an acrylic material or another linear polymer.

5. The microfluidic structure of claim 1, wherein the first and second surfaces are substantially plane and parallel.

6. The microfluidic structure of claim 1, wherein the first and second surfaces are non-parallel.

7. The microfluidic structure of claim 1, wherein the second component is a thin film.

8. The microfluidic structure of claim 1, wherein the microstructure is a microfluidic pathway.

9. The microfluidic structure of claim 1, wherein the microstructure is a microchannel.

10. The microfluidic structure of claim 1, wherein the microstructure is a microreservoir.

11. The microfluidic structure of claim 1, wherein the microstructure is a microvalve.

12. The microfluidic structure of claim 1, wherein the microstructure is a microfilter.

13. The microfluidic structure of claim 1, wherein the second component includes a microfluidic pathway in at least one of the first and second surfaces.

14. The microfluidic structure of claim 1, comprising a plurality of microstructures in at least one of the first and second components.

15. The microfluidic structure of claim 14, wherein at least two of the plurality of microstructures are inter-connected.

16. The microfluidic structure of claim 1, further comprising n additional laminated polymeric components each having first and second surfaces, wherein at least one of each of the first and second surface of each n^th component is fixedly attached to a respective second or first surface of an immediately adjacent component by the bonding agent.

17. The microfluidic structure of claim 16, wherein at least one of the first and second surface of each of at least n−

1 of the n components includes a microstructure.

18. The microfluidic structure of claim 17, wherein at least one of the at least n−

1 components includes a plurality of microstructures.

19. The microfluidic structure of claim 18, wherein at least two of the plurality of microstructures are inter-connected.

20. The microfluidic structure of claim 16, wherein the first and second surfaces of each of the n components are substantially planar and parallel.

21. The microfluidic structure of claim 16, wherein the first and second surfaces of each of the n components are substantially planar and further wherein the first and second surfaces of at least one of the n components are non-parallel.

22. The microfluidic structure of claim 17, wherein the microstructure is a microfluidic pathway.

23. The microfluidic structure of claim 17, wherein the microstructure is a microchannel.

24. The microfluidic structure of claim 17, wherein the microstructure is a microreservoir.

25. The microfluidic structure of claim 17, wherein the microstructure is a microvalve.

26. The microfluidic structure of claim 17, wherein the microstructure is a microfilter.

27. The microfluidic structure of claim 1, wherein the weak solvent has a chemical formula of:

28. The microfluidic structure of claim 1, wherein the weak solvent has a chemical formula of:

29. The microfluidic structure of claim 1, wherein the weak solvent has a chemical formula of:

30. A method for laminating at least two polymeric components to form a laminated, polymeric microfluidic structure, comprising:

applying a weak solvent to a surface of one of the at least two components; and

adjacently contacting opposing surfaces, including the surface having the applied weak solvent, of the at least two components.

31. The method of claim 30, further comprising cooling the one of the at least two components prior to applying the weak solvent.

32. The method of claim 30, further comprising thermally activating the applied weak solvent after adjacently contacting opposing surfaces of the at least two components.

33. The method of claim 30, further comprising applying pressure to the at least two components while thermally activating the applied weak solvent.

34. The method of claim 32, further comprising aligning the at least two components prior to thermally activating the applied weak solvent.

35. The method of claim 30, further comprising sliding the at least two components into a desired alignment after applying the weak solvent and adjacently contacting opposing surfaces of the at least two components.

36. The method of claim 30, further comprising aligning the at least two components into a desired alignment prior to applying the weak solvent and after adjacently contacting opposing surfaces of the at least two components.

37. The method of claim 30, wherein the weak solvent has a chemical formula of:

38. The method of claim 30, wherein the weak solvent has a chemical formula of:

39. The method of claim 30, wherein the weak solvent has a chemical formula of:

40. The method of claim 30, wherein the weak solvent is acetonitrile.

41. A method of making a laminated, polymeric microfluidic structure, comprising:

providing a first component having first and second surfaces, wherein at least one of the surfaces includes a microstructure, further wherein the first component is a polymeric material;

providing at least a second, polymeric component having first and second surfaces, wherein one of the first and second surface of the first component is intended to be fixedly attached to a respective second and first opposing surface of the second component;

applying a weak solvent bonding agent with respect to the polymeric components to at least one of the first and the second component; and

adjacently contacting the opposing surfaces.

42. The method of claim 41, further comprising thermally activating the applied bonding agent after adjacently contacting the opposing surfaces.

43. The method of claim 41, comprising applying the weak solvent bonding agent at approximately room temperature or lower.

44. The method of claim 41, wherein the weak solvent bonding agent is acetonitrile.

45. The method of claim 41, wherein applying the weak solvent bonding agent comprises spraying the bonding agent onto one of the first and second surface of at least one of the first and second component.

46. The method of claim 41, wherein applying the weak solvent bonding agent comprises dipping at least one of the first and second component into a supply of the bonding agent.

47. The method of claim 41, wherein applying the bonding agent comprises adjacently contacting the first and second components and applying the weak solvent bonding agent to at least one common edge of the adjacently contacted components.

48. The method of claim 41, further comprising aligning the first and second components after adjacently contacting them, after applying the bonding agent, prior to thermally activating the applied bonding agent.

49. The method of claim 41, further comprising aligning the first and second components after adjacently contacting them, before applying the bonding agent.

50. The method of claim 41, further comprising applying pressure to the exposed surfaces of the adjacently connected components during the thermal activation of the bonding agent.