Method for covering a microfluidic assembly

• US 20030029724A1
• Filed: 07/30/2002
• Published: 02/13/2003
• Est. Priority Date: 01/30/2000
• Status: Active Grant

• Current Assignee: Gyros Patent AB (Mesa Laboratories Inc.)
• Original Assignee: Gyros Patent AB (Mesa Laboratories Inc.)
• Inventors: Derand, Helene, Larsson, Anders
• Granted Patent: US 7,553,393 B2
• Time in Patent Office: Days
• US Class Current: 204/451
• CPC Class Codes: B01J 2219/00783 Laminate assemblies, i.e. the reactor comprising a stack of plates
• CPC Class Codes: B01L 2200/0689 Sealing
• 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 2300/0887 Laminated structure
• 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 65/02 by heating, with or without pressure
• CPC Class Codes: B29C 65/14 using wave energy , i.e. electromagnetic radiation, or particle radiation using mechanical waves B29C65/06; using ultrasonic waves B29C65/08; pressing means transparent to electromagnetic radiation B29C66/81267
• CPC Class Codes: B29C 65/4815 Hot melt adhesives, e.g. thermoplastic adhesives
• CPC Class Codes: B29C 65/483 Reactive adhesives, e.g. chemically curing 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 66/53461 joining substantially flat covers and/or substantially flat bottoms to open ends of container bodies
• 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 66/72321 consisting of metals or their alloys
• CPC Class Codes: B29C 66/73172 of different hydrophilicity, i.e. the hydrophilicity of one of the parts to be joined being different from the hydrophilicity of the other part
• CPC Class Codes: B29C 66/73176 of different hydrophobicity, i.e. the hydrophobicity of one of the parts to be joined being different from the hydrophobicity of the other part
• CPC Class Codes: B29K 2067/003 PET, i.e. poylethylene terephthalate
• 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 2037/1215 Hot-melt adhesive
• CPC Class Codes: B32B 37/0023 : around holes, apertures or channels present in at least one layer
• CPC Class Codes: Y10T 436/2575 : Volumetric liquid transfer

Abstract

A method for covering a set of open microchannel structures which are fabricated on a planar surface made of plastics and which comprise two or more part areas that have different surface characteristics. The method comprises the steps of: a) providing the surface comprising the set of microchannel structures; b) providing a lid-forming sheet having on one side an even layer of a thermoglue; c) applying the side of the sheet having the thermoglue against the surface carrying the microchannel structure; d) heating the assembly created in step (c) to selectively liquefy the hot-melt adhesive while at the same time pressing the sheet material and the planar surface of the substrate together; e) permitting the resulting laminate-covered microchannel structure to cool. An assembly comprising (a) a planar substrate, the surface of which has a set of one or more open microchannel structures each of which comprises part areas representing different functionalities, and (b) a lid-forming material covering said set of microchannel structures and having one or more openings going from a microchannel structure to ambient atmosphere. The assembly is characterized in that the joint between said surface and said sheet material is a thermoglue that possibly has been cured.

Claims

1. A method for covering a set of open microchannel structures which are fabricated in the surface of a planar substrate and which comprise two or more part areas that have different characteristics, said surface being made of plastics and said method being characterized in that it comprises the steps:

(a) providing the substrate comprising the set of microchannel structures;

(b) providing a lid-forming material having on one side an even layer of a thermoglue (such as a hot-melt adhesive);

(c) applying the side of the material having the thermoglue against the surface carrying the microchannel structures to thereby also cover said microchannel structures;

(d) heating the assembly created in step (c) to selectively liquefying the thermoglue while at the same time pressing the sheet material and the planar surface of the substrate together;

(e) permitting the resulting laminate-covered microchannel structure to cool below the liquefying temperature of the thermoglue..

2. The method of claim 1, characterized in that at least two of said two or more part areas differ with respect to hydrophilicity and/or hydrophobicity.

3. The method of anyone of claims 1-2, characterized in that the channels in the microchannel structure have a sufficient hydrophilicity to permit self-suction.

4. The method of anyone of claims 1-3, characterized in that heating is applied to the lid-forming material.

5. The method of anyone of claims 1-4, characterized in that heating is applied during less than one second.

6. The method of anyone of claims 1-5, characterized in that said set comprises two or more microchannel structures.

7. A microfluidic assembly comprising

(a) a planar substrate, the surface of which has a set of one or more open microchannel structures each of which comprises part areas representing different surface characteristics, and

(b) a lid-forming sheet material covering said set of microchannel structures and having one or more openings going from a microchannel structure to the ambient atmosphere,

characterized in that the joint between said surface and said sheet material is a thermoglue (such as a hot melt adhesive), which possibly is cured.

8. The assembly of claim 7, characterized in that at least two of said part areas differ with respect to hydrophilicity and/or hydrophobicity.

9. The assembly of anyone of claims 7-8, characterized in that said set comprises two or more microchannel structures.

10. The assembly of anyone of claims 7-9, characterized in that at least two of said part areas differ in physical characteristics, such as deep or width of the microchannel structure at the at part areas concerned.

11. The assembly of anyone of claims 7-10, characterized in that there are at least one part area comprising a reactant and at least one other part area not containing said reactant.

12. The assembly of anyone of claims 7-11, characterized in that at least two of said part areas differ in chemical composition.

13. The assembly of anyone of claims 7-12, characterized in that at least two of said part areas are selected from a) application chamber/cavity/area, b) conduit for liquid transport, c) reaction chamber/cavity, d) volume defining unit, e) mixing chamber/cavity, f) chamber for separating components in the sample, for instance by capillary electrophoresis, chromatography and the like, g) detection chamber/cavity, h) waste conduit/chamber/cavity, i) internal valve, j) valve to ambient atmosphere.