Capillary active test element having an intermediate layer situated between the support and the covering

• US 7,799,578 B2
• Filed: 05/29/2007
• Issued: 09/21/2010
• Est. Priority Date: 12/04/1997
• Status: Expired due to Fees

• Current Assignee: Roche Diagnostics GmbH (Roche Holding AG)
• Original Assignee: Roche Diagnostics GmbH (Roche Holding AG)
• Inventors: Zimmer, Volker
• Primary Examiner(s): ALEXANDER, LYLE
• Application Number:
  US11/807,548
• Publication Number:
  US 20070266803A1
• Time in Patent Office: 1,211 Days
• Field of Search: 422/100, 422/61, 436/165, 436/174
• US Class Current: 436/174
• CPC Class Codes: B01L 2200/027 for microfluidic devices
• CPC Class Codes: B01L 2300/0825 Test strips
• CPC Class Codes: B01L 2300/0887 Laminated structure
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 3/5023 with a sample being transported to, and subsequently stored in an absorbent for analysis
• CPC Class Codes: G01N 2035/00108 Test strips, e.g. paper
• CPC Class Codes: G01N 33/54386 Analytical elements
• CPC Class Codes: Y10T 436/25 including sample preparation
• CPC Class Codes: Y10T 436/255 including use of a solid sorbent, semipermeable membrane, or liquid extraction

Abstract

The invention concerns a device and method for withdrawing samples of liquid samples for analytical elements. The device includes a carrier and a cover with a surface that cooperates with a surface of the carrier to form a channel. The channel has an opening defined by at least one edge. At least one notch in the form of a partial groove extends into the at least one edge of the opening so that one side of the edge of the opening is at least partially interrupted by the at least one notch. The notch forms a sample application opening by exposing the surface, whose extension forms an inner surface of the channel.

Claims

1. A device for withdrawing samples of liquid samples for analytical elements, wherein the device comprises:

a carrier and

a cover having a surface that cooperates with a surface of the carrier to form a channel, the channel having an opening located generally at one end of the device and generally defined by opposing edges of the carrier and the cover,

wherein at least one notch in the form of a partial groove extends into at least one of the edges of the opening of the channel so that one side of the edge of the opening is at least partially interrupted by the at least one notch, and the notch forming the sample opening so that a surface opposite to the notch is exposed, the exposed surface forming an inner surface of the channel.

2. Device as claimed in claim 1, wherein at least two notches are located next to one another.

3. Device as claimed in claim 1, wherein notches are staggered on opposite sides.

4. Device as claimed in claim 1, wherein at least one of the surfaces forms an inner surface of the channel that is capable of capillary liquid transport and is hydrophilized.

5. Device as claimed in claim 4, wherein an exposed surface opposite to the notch is hydrophilized.

6. Device as claimed in claim 5, wherein a layer of oxidized aluminum is used for the hydrophilization.

7. Device as claimed in claim 4, further comprising a second cover and an intermediate layer positioned between the second cover and the carrier.

8. Device as claimed in claim 4, wherein the hydrophilization is achieved by a hydrophilic material.

9. Device as claimed in claim 4, wherein the hydrophilization is achieved by a hydrophilic layer.

10. Device as claimed in claim 6, wherein the hydrophilization is achieved by a hydrophilic layer.

11. Device as claimed in claim 10, wherein a layer of oxidized aluminum is used for the hydrophilization.

12. A method for withdrawing a liquid sample into an analytical element, the method comprising the steps of

proving a device that comprises a carrier and a cover having a surface that cooperates with a surface of the carrier to form a capillary-active channel having a sample application opening located generally at one end of the device and defined by opposing edges of the carrier and the cover and wherein at least one notch in the form of a partial groove extends into at least one of the edges of the sample application opening of the channel so that one side of the edge of the sample application opening is at least partially interrupted by the at least one notch and the notch forming the sample opening so that a surface opposite to the notch is exposed, the exposed surface comprises a capillary active zone at least in the direction of the capillary-active channel, and

contacting the edge of the sample application opening adjacent to the notch with the liquid sample so that at least one site of a liquid drop comes into contact with the capillary active zone and the liquid sample is transported by capillary forces into the channel.

13. Device as claimed in claim 12, wherein at least two notches are located next to one another.

14. Device as claimed in claim 12, wherein at least two notches are staggered on opposite sides.

15. Device as claimed in claimed 12, wherein at least one of the surfaces forms an inner surface of the channel capable of capillary liquid transport and is hydrophilized.

16. A device for withdrawing samples of liquid samples for analytical elements, wherein the device comprises:

a carrier and

a cover having a surface that cooperates with a surface of the carrier to form a capillary-active channel,

wherein at least one notch in one of the carrier and the cover forms a sample application opening to the channel by exposing a portion of the surface of the other of the carrier and the cover, said notch forming the sample opening so that a surface opposite to the notch is exposed, wherein the exposed portion forms an inner surface of the channel, the notch bordering directly on a capillary active zone at least in the direction of the capillary-active channel.

17. Device as claimed in claim 16, wherein at least two notches are located next to one another.

18. Device as claimed in claim 17, wherein notches are staggered on opposite sides.

19. Device as claimed in claim 16, wherein at least one of the surfaces forms an inner surface of the channel capable of capillary liquid transport and is hydrophilized.

20. Device as claimed in claim 19, wherein a layer of oxidized aluminum is used for the hydrophilization.