Extraction articles and methods

• US 6,492,183 B1
• Filed: 03/13/2001
• Issued: 12/10/2002
• Est. Priority Date: 09/14/1998
• Status: Expired due to Term

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Jacobson, Jason R., Bayer, Glen H. Jr., Wisted, Eric E., Ansera, Taib K., Berrigan, Michael R., Perman, Craig A.
• Primary Examiner(s): Drodge, Joseph W.
• Application Number:
  US09/787,133
• Time in Patent Office: 637 Days
• Field of Search: 210/198.2, 210/198.3, 210/263, 210/455, 210/490, 210/496, 210/500.36, 210/502.1, 210/503, 210/505, 210/508, 210/656, 210/660, 156/73.1, 156/73.3, 156/73.4, 422/101, 436/177, 436/178, 738/632.3
• US Class Current: 436/178
• CPC Class Codes: B01D 11/0219 Fixed bed of solid material
• CPC Class Codes: B01D 17/0202 by ab- or adsorption
• CPC Class Codes: B01D 29/012 Making filtering elements making bag, cage, hose, tube, sleeve or like filtering elements B01D29/111
• CPC Class Codes: B01J 20/28004 Sorbent size or size distribution, e.g. particle size
• CPC Class Codes: B01J 20/28007 with size in the range 1-100 nanometers, e.g. nanosized particles, nanofibers, nanotubes, nanowires or the like carbon nanostructures B01J20/205
• CPC Class Codes: B01J 20/28014 characterised by their form
• CPC Class Codes: B01J 20/28028 Particles immobilised within fibres or filaments
• CPC Class Codes: B01J 20/28033 Membrane, sheet, cloth, pad, lamellar or mat
• CPC Class Codes: B01J 20/28035 with more than one layer, e.g. laminates, separated sheets
• CPC Class Codes: B32B 17/10724 containing polyamide
• CPC Class Codes: B32B 17/10752 containing polycarbonate
• CPC Class Codes: B32B 17/10779 containing polyester
• CPC Class Codes: B32B 2262/00 Composition or structural features of fibres which form a fibrous or filamentary layer or are present as additives
• CPC Class Codes: B32B 2323/04 Polyethylene
• CPC Class Codes: B32B 2323/10 Polypropylene
• CPC Class Codes: B32B 5/022 Non-woven fabric
• CPC Class Codes: B32B 5/22 characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed layer formed of natural mineral fibres or particles next to a foam layer B32B19/047, next to a layer made of particles B32B19/048, or next to a fibrous or filamentary layer B32B19/06; paper layer or cardboard layer next to a paper layer or cardboard layer B32B29/005, next to a foam layer B32B29/007, next to a fibrous or filamentary layer B32B29/02, or next to a particulate layer B32B29/04
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor
• CPC Class Codes: Y10T 436/25375 Liberation or purification of sample or separation of material from a sample [e.g., filtering, centrifuging, etc.]
• CPC Class Codes: Y10T 436/255 : including use of a solid sorbent, semipermeable membrane, or liquid extraction

Abstract

This invention provides a one-piece multilayer article for use in solid phase extraction that includes at least two porous support layers and a solid phase extraction medium, wherein the porous support layers are thermo-mechanically attached at at least one thermo-mechanical attachment site. At least one of the porous support layers can be a prefilter layer.

Claims

1. A one-piece multilayer solid phase extraction article comprising

a) a first porous support layer,

b) a second porous support layer attached at least one thermo-mechanical attachment site to said first porous layer, and

c) a layer of solid phase extraction medium disposed between, and in intimate contact with, the first and second porous support layers such that a portion of the solid phase extraction medium is bound within the thermo-mechanical attachment site.

2. The article in claim 1 wherein at least one of said first and second porous support layers is a thermoplastic material.

3. The article in claim 2 wherein said thermoplastic material comprises a polymer selected from the group consisting of polyolefin, polycarbonate, polyester and polyamide.

4. The article in claim 2 wherein said thermoplastic material comprises a polyolefin selected from the group consisting of polyethylene, polypropylene, ethylene/propylene copolymers and blends thereof.

5. The article in claim 1 wherein said thermo-mechanical attachment site is formed by ultrasonic welding.

6. The article in claim 1 wherein said first porous support layer is a pre-filter having a solidity of no greater than about 20%, a thickness of at least about 0.5 mm, and a basis weight of at least about 70 g/m².

7. The article of claim 1 wherein said first porous support layer is a non-woven web.

8. The article of claim 7 wherein said nonwoven web comprises thermoplastic microfibers.

9. The article of claim 8 wherein said microfibers are melt blown.

10. The article in claim 9 wherein said melt blown microfibers have a diameter of no less than about 0.1 microns and no greater than about 20 microns.

11. The article in claim 1 wherein said first porous support layer comprises multiple layers of porous material, wherein at least one of said multiple layers of porous material is in intimate contact with said layer of solid phase extraction medium.

12. The article in claim 1 wherein the second porous support layer comprises multiple layers of porous material, wherein at least one of said multiple layers of porous material is in intimate contact with the layer of solid phase extraction medium.

13. The article in claim 1 wherein said solid phase extraction medium comprises a fibril matrix comprising the fluoropolymer with sorptive particles enmeshed therein.

14. The article in claim 13 wherein said sorptive particles comprise silica particles coated with an aliphatic hydrocarbon.

15. The article in claim 13 wherein said solid phase extraction medium further comprises glass particles enmeshed within the fibril matrix.

16. The article in claim 11 which is in the form of a circular disk or a polygon.

17. The article in claim 16 wherein said thermo-mechanical attachment site is at the perimeter.

18. The article in claim 16 wherein the solid phase extraction medium is bound within said thermo-mechanical attachment site at at least one point within the perimeter.

19. The article of claim 1 wherein said first and second porous support layers comprise the same thermoplastic polymeric material.

20. The article of claim 1 wherein the solid phase extraction medium comprises a fluoropolymer.

21. A method of extracting an analyte from a sample comprising

a) providing a one-piece multilayer solid phase extraction article comprising

i) a first porous support layer,

ii) a second porous support layer attached to said first porous support layer at at least one thermo-mechanical attachment site, and

iii) a layer of solid phase extraction medium disposed between, and in intimate contact with, the first and second porous support layers such that a portion of the solid phase extraction medium is bound within the thermo-mechanical attachment site;

and

b) passing the sample through said one-piece multilayer solid phase extraction article.

22. The method according to claim 21, wherein said first porous support layer is a pre-filter having a solidity of no greater than about 20%, a thickness of at least about 0.5 mm, and a basis weight of at least about 70 g/m².

23. The method according to claim 21 wherein at least one of said first and second porous support layers comprises a thermoplastic material.

24. A method of thermo-mechanically making a one-piece multilayer extraction article comprising:

a) stacking a first porous support layer, a second porous support layer, and a layer of solid phase extraction medium therebetween;

b) positioning said stack of layers in an ultrasonic welder, said welder comprising an anvil and an ultrasonic horn; and

c) pinching said stack of layers between said anvil and said horn to form at least one thermo-mechanical attachment site between said first and second porous support layers, wherein at least a portion of the solid phase extraction medium is bound within said thermo-mechanical attachment site.

25. The method according to claim 24 wherein said anvil comprises a cutting angle sufficient to cut said stack of layers at substantially the same time as the formation of said thermo-mechanical attachment site.

26. The method according to claim 24 wherein at least one of said first and second porous support layers comprises a thermoplastic material.

27. The method according to claim 26 wherein said thermoplastic material comprises a polymer selected from the group consisting of polyolefin, polycarbonate, polyester and polyamide.

28. The method according to claim 26 wherein said thermoplastic polymeric material comprises a polyolefin selected from the group consisting of polyethylene, polypropylene ethylene/propylene copolymers and blends thereof.

29. The method according to claim 24 wherein said first porous support layer is a pre-filter having a solidity of no greater than about 20% a thickness of at least about 0.5 mm and a basis weight of at least about 70 g/m².

30. The method according to claim 24 wherein said first porous support layer comprises a non-woven web.

31. The method according to claim 30 wherein said nonwoven web comprises micro fibers.

32. The method according to claim 31 wherein said microfibers are melt blown.

33. The method according to claim 32 wherein said melt blown microfibers have a diameter of no less than about 0.1 microns and no greater than about 20 microns.

34. The method according to claim 24 wherein said first and second porous support layers comprise the same thermoplastic polymeric material.

35. The method according to claim 24 wherein said solid phase extraction medium comprises a fibril matrix comprising the fluoropolymer having sorptive particles enmeshed therein.

36. The method according to claim 35 wherein said sorptive particles comprise silica particles coated with an aliphatic hydrocarbon.

37. The method according to claim 35 wherein said solid phase extraction medium further comprises glass particles enmeshed within the fibril matrix.

38. The method of claim 24 wherein the solid phase extraction medium comprises a fluoropolymer.