Frit material and bonding method for microfluidic separation devices
View Patent ↗A multi-layer microfluidic separation device comprises a polymeric membrane frit that may be securely bonded within the device and minimizes lateral wicking. Stationary phase material having an average particle size is retained by a frit having an average pore size that is smaller than the average particle size. In one embodiment, a secure bond is ensured by treating the polymer to match its surface energy to that of the materials to which it is bound. Treatments include plasma treatment, irradiation and the application of acids.
1. A multi-layer separation device comprising:
a first substantially planar adhesiveless polymeric device layer defining a separation channel;
a second substantially planar adhesiveless polymeric device layer defining an aperture;
a third substantially planar adhesiveless polymeric device layer defining an exit channel, wherein the second device layer is disposed between the first device layer and the third device layer; and
an adhesiveless polymeric frit disposed between the second device layer and the third device layer;
wherein the separation channel is in fluid communication with the exit channel by way of the aperture and the frit; and
wherein the second device layer and the third device layer are sufficiently bound around the frit to prevent substantially any lateral flow between the frit and the second device layer and between the frit and the third device layer at an operating pressure.
2. The device of claim 1 wherein the operating pressure is at least about 10 psi (69 kPa).
3. The device of claim 1 wherein the operating pressure is at least about 50 psi (345 kPa).
4. The device of claim 1 wherein the operating pressure is at least about 100 psi (690 kPa).
5. The device of claim 1 wherein the operating pressure is at least about 500 psi (3450 kPa).
6. The device of claim 1 , further comprising a stationary phase material contained within the separation channel.
7. The device of claim 1 wherein the stationary phase material includes particulate material having an average particle size.
8. The device of claim 7 wherein the frit has an average pore size, and the average pore size is smaller than the average particle size.
9. The device of claim 7 wherein the frit has an average pore size that is no greater than about one tenth of the average particle size.
10. The device of claim 1 wherein the frit comprises a permeable polypropylene membrane.
11. The device of claim 1 wherein the frit comprises a track-etched membrane.
12. The device of claim 1 wherein the frit comprises a stretched polymer film.
13. The device of claim 1 wherein the frit has a mesh structure.
14. The device of claim 1 wherein the frit is about 25 microns thick, is about 55% porous, and has a plurality of pores about 0.209×0.054 microns in size.
15. The device of claim 1 wherein:
the second device layer has a first surface energy;
the third device layer has a second surface energy;
the frit has a third surface energy; and
the difference between any of the first surface energy, the second surface energy, and the third surface energy is less than or equal to about 5 dynes/cm.
16. The device of claim 15 wherein the difference between any of the first surface energy, the second surface energy, the third surface energy is less than or equal to about 2 dynes/cm.
17. The device of claim 15 wherein the difference between any of the first surface energy, the second surface energy, and the third surface energy is less than or equal to about 1 dynes/cm.
18. The device of claim 15 wherein the difference between any of the first surface energy, the second surface energy, and the third surface energy is about 0 dynes/cm.
19. The device of claim 1 wherein any of the first stencil layer and the second stencil layer comprises a substantially adhesiveless polyolefin material.
20. The device of claim 19 wherein the substantially adhesiveless polyolefin material comprises unoriented polypropylene.
21. The device of claim 1 wherein the frit has a melting point temperature that is significantly higher than the melting point temperature of any of the first stencil layer and the second stencil layer.
22. The device of claim 1 wherein the frit comprises a surface treated polymer membrane.
23. The device of claim 1 wherein each of the first device layer, the second device layer, and the third device layer is substantially metal-free.
24. The device of claim 1 wherein any of the first device layer, the second device layer, and the third device layer is stencil layer.
25. The device of claim 1 wherein a portion of the second device layer and a portion of the third device layer are interpenetrably bound.
26. The device of claim 1 wherein any of the separation channel, the aperture, and the exit channel is microfluidic.
27. A multi-layer separation device comprising:
a first substantially planar adhesiveless polymeric device layer defining a plurality of separation channels;
a second substantially planar adhesiveless polymeric device layer defining a plurality of apertures;
a third substantially planar adhesiveless polymeric device layer defining a plurality of exit channels, wherein the second device layer is disposed between the first device layer and the third device layer; and
an adhesiveless polymeric frit disposed between the second device layer and the third device layer;
wherein each separation channel of the plurality of separation channels is in fluid communication with an exit channel of the plurality of exit channels by way of an aperture of the plurality of apertures and the frit; and
wherein the second device layer and the third device layer are sufficiently bound around the frit to prevent substantially any lateral flow between the frit and the second device layer and between the frit and the third device layer at an operating pressure.
28. The device of claim 27 wherein the operating pressure is at least about 10 psi (69 kPa).
29. The device of claim 27 wherein the operating pressure is at least about 50 psi (345 kPa).
30. The device of claim 27 wherein the operating pressure is at least about 100 psi (690 kPa).
31. The device of claim 27 wherein the operating pressure is at least about 500 psi (3450 kPa).
32. The device of claim 27 wherein each separation column of the plurality of separation columns contains a stationary phase material.
33. The of claim 32 wherein the stationary phase material includes particulate material having an average particle size.
34. The device of claim 33 wherein the frit has an average pore size, and the average pore size is smaller than the average particle size.
35. The device of claim 33 wherein the frit has an average pore size that is no greater than about one tenth of the average particle size.
36. The device of claim 27 wherein the frit comprises a permeable polypropylene membrane.
37. The device of claim 27 wherein the frit comprises a track-etched membrane.
38. The device of claim 27 wherein the frit comprises a stretched polymer film.
39. The device of claim 27 wherein the frit has a mesh structure.
40. The device of claim 27 wherein the frit is about 25 microns thick, is about 55% porous, and has a plurality of pores about 0.209×0.054 microns in size.
41. The device of claim 27 wherein:
the first device layer has a first surface energy;
the second device layer has a second surface energy;
the frit has a third surface energy; and
the difference between any of the first surface energy, the second surface energy, and the third surface energy is less than or equal to about 5 dynes/cm.
42. The device of claim 41 wherein the difference between any of the first surface energy, the second surface energy, the third surface energy is less than or equal to about 2 dynes/cm.
43. The device of claim 41 wherein the difference between any of the first surface energy, the second surface energy, and the third surface energy is less than or equal to about 1 dynes/cm.
44. The device of claim 41 wherein the difference between any of the first surface energy, the second surface energy, and the third surface energy is about 0 dynes/cm.
45. The device of claim 27 wherein any of the first device layer and the second device layer comprises a substantially adhesiveless polyolefin material.
46. The device of claim 45 wherein the substantially adhesiveless polyolefin material comprises unoriented polypropylene.
47. The device of claim 27 wherein the frit has a melting point temperature that is significantly higher than the melting point temperature of any of the first device layer and the second device layer.
48. The device of claim 27 wherein the frit comprises a surface treated polymer membrane.
49. The device of claim 27 wherein each of the first device layer, the second device layer, and the third device layer is substantially metal-free.
50. The device of claim 27 wherein any of the first device layer, the second device layer, and the third device layer is a stencil layer.
51. The device of claim 27 wherein a portion of the second device layer and a portion of the third device layer are interpenetrably bound.
52. The device of claim 27 wherein the plurality of separation channels, the plurality of apertures, and the plurality of exit channels are microfluidic.