POLYMER MICROFILTERS AND METHODS OF MANUFACTURING THE SAME

• US 20130059308A1
• Filed: 04/01/2011
• Published: 03/07/2013
• Est. Priority Date: 05/03/2010
• Status: Active Grant

• Current Assignee: Creatv Microtech, Inc. (Thermo Fisher Scientific Incorporated)
• Original Assignee: Creatv Microtech, Inc. (Thermo Fisher Scientific Incorporated)
• Inventors: Tang, Cha-Mei, Makarova, Olga V., Amstutz, Platte T.
• Granted Patent: US 11,613,115 B2
• Time in Patent Office: Days
• US Class Current: 435/6.11
• CPC Class Codes: B01D 2239/0421 Rendering the filter material hydrophilic
• CPC Class Codes: B01D 2239/0478 on a layer of the filter
• CPC Class Codes: B01D 2239/10 Filtering material manufacturing
• CPC Class Codes: B01D 2323/345 UV-treatment
• CPC Class Codes: B01D 2325/08 Patterned membranes
• CPC Class Codes: B01D 29/00 Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
• CPC Class Codes: B01D 39/16 of organic material, e.g. synthetic fibres
• CPC Class Codes: B01D 39/1692 Other shaped material, e.g. perforated or porous sheets
• CPC Class Codes: B01D 67/0027 by stretching
• CPC Class Codes: B01D 67/0034 by micromachining techniques, e.g. using masking and etching steps, photolithography
• CPC Class Codes: B01D 67/0088 Physical treatment with compounds, e.g. swelling, coating or impregnation
• CPC Class Codes: B01D 69/12 Composite membranes; Ultra-thin membranes
• CPC Class Codes: B01D 69/1213 Laminated layers
• CPC Class Codes: B01D 71/46 Epoxy resins
• CPC Class Codes: B01L 2300/0681 Filter
• CPC Class Codes: B01L 3/50 Containers for the purpose of retaining a material to be analysed, e.g. test tubes devices for taking samples of blood A61B5/15
• CPC Class Codes: B01L 3/502 with fluid transport, e.g. in multi-compartment structures centrifugal-type cuvettes G01N21/07; analysis by separation into components G01N30/00; automatic analysers G01N35/00
• CPC Class Codes: B01L 3/5635 connecting two containers face to face, e.g. comprising a filter
• CPC Class Codes: B01L 9/00 Supporting devices; Holding devices
• CPC Class Codes: B31B 2100/0022 made from tubular webs or blanks, including by tube or bottom forming operations
• CPC Class Codes: B31B 50/006 : Controlling; Regulating; Measuring; Improving safety
• CPC Class Codes: B31B 50/88 : Printing; Embossing
• CPC Class Codes: B41F 19/008 : with means for stamping or cutting out
• CPC Class Codes: B41F 33/0036 : Devices for scanning or checking the printed matter for quality control
• CPC Class Codes: B41F 33/0081 : Devices for scanning register marks
• CPC Class Codes: G01N 1/4005 : by transferring a selected component through a membrane
• CPC Class Codes: G01N 1/4077 : by other techniques involving separation of suspended solids
• CPC Class Codes: G01N 2001/4088 : filtration
• CPC Class Codes: G01N 33/5005 : involving human or animal cells immunoassay G01N33/56966; immunoassays of protozoa G01N33/56905; protozoa in screening assays C12Q1/025
• CPC Class Codes: Y10T 29/49826 : Assembling or joining
• CPC Class Codes: Y10T 29/49963 : Threaded fastener

Abstract

A microfilter comprising a polymer layer formed from epoxy-based photo-definable dry film, and a plurality of apertures each extending through the polymer layer. A method of forming a microfilter is also disclosed. The method includes providing a first layer of epoxy-based photo-definable dry film disposed on a substrate, exposing the first layer to energy through a mask to form a pattern, defmed by the mask, in the first layer of dry film, forming, from the exposed first layer of dry film, a polymer layer having a plurality of apertures extending therethrough, the plurality of apertures having a distribution defined by the pattern, and removing the polymer layer from the substrate.

Claims

1. A microfilter comprising:

a polymer layer formed from epoxy-based photo-definable dry film; and

a plurality of apertures each extending through the polymer layer.

2. The microfilter of claim 1, wherein the polymer layer has sufficient strength and flexibility to filter liquid, and wherein the apertures are sized to allow passage of a first type of bodily fluid cell and to prevent passage of a second type of bodily fluid cell.

3. The microfilter of claim 2, wherein the apertures have a width that is approximately the same as the thickness of the polymer layer.

4. The microfilter of claim 1, further comprising:

a coating of a metallic substance on at least one surface of the polymer layer.

5. The microfilter of claim 4, further comprising:

analyte recognition elements disposed on the coating.

6. The microfilter of claim 1, further comprising:

a coating of analyte recognition elements on at least one surface of the polymer layer.

7. The microfilter of claim 1, wherein the dry film includes a polyfunctional epoxy resin.

8. A multi-layer microfilter comprising:

a first polymer layer formed from epoxy-based photo-definable dry film and having a first aperture extending therethrough;

a second polymer layer formed from epoxy-based photo-definable dry film and having a second aperture extending therethrough, wherein the first and second apertures at least partially define a non-linear passage extending through the first and second layers.

9. The microfilter of claim 8, further comprising:

a third polymer layer formed from epoxy-based photo-definable dry film and having a third aperture extending therethrough, wherein the third layer is disposed between the first and second polymer layers such that the first, second and third apertures define a non-linear passage through the first, second and third layers.

10. The microfilter of claim 9, wherein the first and third apertures are first and third elongate trenches, respectively, wherein the first and third trenches are substantially perpendicular to one another.

11. The microfilter of claim 10, wherein the second opening is a second elongate trench substantially parallel to the first trench.

12. The microfilter of claim 9, wherein the first, second and third polymer layers each include a plurality of apertures forming a plurality of non-linear passages each extending through the first, second and third layers.

13. The microfilter of claim 8, further comprising:

a coating of a metallic substance on at least one surface of the first polymer layer.

14. The microfilter of claim 13, further comprising:

analyte recognition elements disposed on the coating.

15. The microfilter of claim 8, further comprising:

a coating of analyte recognition elements on at least one surface of the first polymer layer.

16. A method of forming a microfilter comprising:

providing a first layer of epoxy-based photo-definable dry film disposed on a substrate;

exposing the first layer to energy through a mask to form a pattern, defined by the mask, in the first layer of dry film;

forming, from the exposed first layer of dry film, a polymer layer having a plurality of apertures extending therethrough, the plurality of apertures having a distribution defined by the pattern; and

removing the polymer layer from the substrate.

17. The method of claim 16, wherein said exposing the first layer of dry film to the energy through the mask comprises:

exposing the first layer of dry film to ultraviolet (UV) light through an optical mask defining the pattern.

18. The method of claim 16, wherein said exposing the first layer of dry film to the energy through the mask comprises:

exposing the first layer of dry film to X-rays through an X-ray mask defining the pattern.

19. The method of claim 16, wherein said forming the polymer layer from the exposed first layer of dry film comprises:

developing the exposed first layer of dry film.

20. The method of claim 16, further comprising:

coating at least one surface of the polymer layer with a metallic substance.

21. The method of claim 20, further comprising:

attaching analyte recognition elements to the coating.

22. The method of claim 16, further comprising:

coating at least one surface of the polymer layer with analyte recognition elements.

23. The method of claim 16, wherein said providing the first layer of epoxy-based photo-definable dry film disposed on a substrate comprises:

unrolling a portion of a dry film structure from a roll of the dry film structure, wherein the dry film structure includes the first layer of dry film disposed on the substrate; and

advancing the portion of a dry film structure to a location between the mask and a support.

24. The method of claim 16, wherein said providing the first layer of epoxy-based photo-definable dry film disposed on a substrate comprises:

providing a plurality of layers of epoxy-based photo-definable dry film stacked on one another, wherein each layer of dry film is disposed on a respective substrate.

25. The method of claim 24, wherein said exposing the first layer to energy comprises:

simultaneously exposing each layer of the plurality of layers of dry film to energy through a mask to form in each of the layers of dry film a pattern defined by the mask.

26. The method of claim 24, wherein said providing a plurality of layers comprises:

unrolling a portion of a dry film structure from a roll of the dry film structure for each of a plurality of dry film structures, wherein each dry film structure includes a layer of epoxy-based photo-definable dry film disposed on a substrate; and

advancing the portion of each of the dry film structures to a location between the mask and a support.

27. A microfilter formed using the method of claim 16.

28. A method of forming a multi-layer microfilter comprising:

forming a first polymer layer comprising a plurality of first apertures from a first layer of epoxy-based photo-definable dry film disposed on a substrate;

laminating a second layer of epoxy-based photo-definable dry film on the first polymer layer; and

forming a second polymer layer comprising a plurality of second apertures from the second layer of dry film.

29. The method of claim 28, further comprising:

laminating a third layer of epoxy-based photo-definable dry film on the second microfilter; and

forming a third polymer layer comprising a plurality of third apertures from the third layer of dry film.

30. The method of claim 29, wherein a non-linear passage extending through the multi-layer microfilter is at least partially defined by one of the first apertures, one of the second apertures, and one of the third apertures.

31. The method of claim 28, wherein at least one of the first apertures is a first elongate trench and at least one of the second apertures is a second elongate trench substantially perpendicular to the first elongate trench.

32. The method of claim 28, further comprising:

coating at least one surface of at least one of the first and second polymer layers with a metallic substance.

33. The method of claim 32, further comprising:

attaching analyte recognition elements to the coating.

34. The method of claim 28, further comprising:

coating at least one surface of the first polymer layer with analyte recognition elements.

35. A multi-layer microfilter formed using the method of claim 28.

36. A method of using a microfilter comprising:

passing a liquid through a plurality of apertures of a microfilter formed from an epoxy-based photo-definable dry film, wherein the microfilter has sufficient strength and flexibility to filter the liquid, and wherein the apertures are sized to allow passage of a first type of bodily fluid cell and to prevent passage of a second type of bodily fluid cell.

37. The method of claim 36, further comprising:

positioning the microfilter in a filter holder before passing the liquid through the plurality of apertures; and

removing the microfilter from the filter holder after passing the liquid through the plurality of apertures.

38. The method of claim 36, wherein passing the liquid through the plurality of apertures comprises:

capturing, using the microfilter, circulating tumor cells present in the liquid as the liquid is drawn through the plurality of apertures.

39. The method of claim 38, further comprising:

performing, on the captured circulating tumor cells, one or more of cell identification, cell enumeration, cell characterization, culturing, and separation of the cells.

40. The method of claim 36, wherein the microfilter includes a coating of a metallic substance on at least one surface of the microfilter.

41. The method of claim 40, wherein the microfilter includes analyte recognition elements attached to the coating.

42. The method of claim 36, wherein the microfilter includes a coating of analyte recognition elements on at least one surface of the microfilter.