Device having a flow channel

• US 6,939,450 B2
• Filed: 10/08/2002
• Issued: 09/06/2005
• Est. Priority Date: 10/08/2002
• Status: Active Grant

• Current Assignee: Abbott Laboratories Incorporated
• Original Assignee: Abbott Laboratories Incorporated
• Inventors: Karinka, Shridhara Alva, Tess, Mark E.
• Primary Examiner(s): NOGUEROLA, ALEXANDER STEPHAN
• Application Number:
  US10/266,548
• Publication Number:
  US 20040067166A1
• Time in Patent Office: 1,064 Days
• Field of Search: 422 55- 58, 422 8201- 8203, 422/100, 422/99, 204/409, 204/403.01, 204/403.14, 204/403.03
• US Class Current: 204/409
• CPC Class Codes: B01L 2300/0645 Electrodes
• CPC Class Codes: B01L 2300/0825 Test strips
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 2400/0688 surface tension valves, capillary stop, capillary break
• CPC Class Codes: B01L 3/502723 characterised by venting arrangements
• CPC Class Codes: C12Q 1/001 Enzyme electrodes
• CPC Class Codes: G01N 27/3272 Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels optical biosensors G01N33/52

Abstract

A device having a flow channel, wherein at least one flow-terminating interface is used to control the flow of liquid in the flow channel. The flow-terminating interface prevents the flow of the liquid beyond the interface. In one aspect, the invention provides a sensor, such as, for example, a biosensor, in the form of a strip, the sensor being suitable for electrochemical or optical measurement. The sensor comprises a base layer and a cover layer, and the base layer is separated from the cover layer by a spacer layer. The base layer, cover layer, and spacer layer define a flow channel into which a liquid sample is drawn therein and flows therethrough by means of capillary attraction. The flow of the sample is terminated by a flow-terminating interface positioned in the flow channel.

Claims

1. A sensor strip comprising:

(a) a base layer having a first major surface and a second major surface;

(b) a cover layer having a first major surface and a second major surface, the first major surface of said cover layer facing the first major surface of said base layer;

(c) a spacer layer interposed between the first major surface of said cover layer and the first major surface of said base layer to separate said cover layer from said base layer;

(d) a flow channel having walls formed by said first major surface of said cover layer, said first major surface of said base layer, and said spacer layer, said flow channel having a reaction site therein, wherein said reaction site includes an electrode arrangement, said flow channel being of such dimensions that a liquid sample can be drawn therein and can flow therethrough by means of capillary attraction;

(e) a flow-terminating interface applied to or formed in said first major surface of said cover layer, said flow-terminating interface capable of terminating flow of a sample of liquid in said flow channel at said flow-terminating interface;

(f) a sample application zone, where a liquid sample is introduced into said flow channel; and

(g) at least one opening communicating with said flow channel to allow gas to be vented from said flow channel.

2. The sensor strip of claim 1, wherein said electrode arrangement comprises a working electrode and a dual-purpose reference electrode/counter electrode.

3. The sensor strip of claim 2, wherein said electrode arrangement further includes a trigger electrode.

4. The sensor strip of claim 2, wherein said electrode arrangement further includes a reagent system on at least said working electrode.

5. The sensor strip of claim 4, wherein said reagent system comprises an enzyme and a mediator for said enzyme.

6. The sensor strip of claim 1, wherein said electrode arrangement comprises a working electrode, a counter electrode, and a reference electrode.

7. The sensor strip of claim 6, wherein said electrode arrangement further includes a trigger electrode.

8. The sensor strip of claim 6, wherein said electrode arrangement further includes a reagent system on at least said working electrode.

9. The sensor strip of claim 8, wherein said reagent system comprises an enzyme and a mediator for said enzyme.

10. The sensor strip of claim 1, wherein said at least one opening is formed in said spacer layer.

11. The sensor strip of claim 1, wherein said at least one opening is formed in said cover layer.

12. The sensor strip of claim 1, wherein said spacer layer comprises a layer of adhesive.

13. The sensor strip of claim 12, wherein said adhesive is formed from a radiation-curable adhesive.

14. The sensor strip of claim 12, wherein said adhesive is formed from a water-borne adhesive or a solvent-borne adhesive.

15. The sensor strip of claim 1, wherein said spacer layer comprises a backing having a layer of adhesive on both major surfaces thereof.

16. The sensor strip of claim 1, wherein said flow-terminating interface is a hydrophilic/hydrophobic interface.

17. The sensor strip of claim 16, wherein said hydrophilic/hydrophobic interface comprises a layer of hydrophobic material having a coating of hydrophilic material thereon, a portion of said hydrophilic material being removed to expose said hydrophobic material to said liquid in said flow channel.

18. The sensor strip of claim 16, wherein said hydrophilic/hydrophobic interface comprises a layer of hydrophilic material having a coating of hydrophobic material thereon, a portion of said hydrophobic material being removed to expose said hydrophilic material to said liquid in said flow channel.

19. The sensor strip of claim 1 wherein said first major surface of said cover layer comprises a hydrophilic material having a hydrophobic coating applied to a portion thereof.

20. The sensor strip of claim 1, wherein said first major surface of said cover layer comprises a hydrophobic material having a hydrophilic coating applied to a portion thereof.

21. The sensor strip of claim 1, wherein said flow-terminating interface comprises a plurality of openings in said cover layer.

22. The sensor strip of claim 1, wherein at least one dimension of said flow channel at said flow-terminating interface is of sufficient size that the force attributable to capillary attraction is insufficient to permit additional fluid to enter said flow channel.

23. A device for allowing the flow of a liquid and for terminating the flow of said liquid, said device comprising;

(a) a flow channel bounded by a wall, said flow channel having dimensions to allow a liquid to flow by capillary attraction; and

(b) a flow-terminating interface to terminate the flow of said liquid in said flow channel at said flow-terminating interface, wherein said flow-terminating interface comprises a plurality of openings in said wall of said flow channel.