Test unit and test system for analyzing body fluids

• US 20090093735A1
• Filed: 09/29/2008
• Published: 04/09/2009
• Est. Priority Date: 03/29/2006
• Status: Abandoned Application

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Inventors: Schnarrwyler, Denise, Korner, Stephan, Niederberger, Brigitte
• Application Number:
  US12/240,341
• Publication Number:
  US 20090093735A1
• Time in Patent Office: Days
• US Class Current: 600/583
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150358 Strips for collecting blood, e.g. absorbent optical reagent test strips G01N21/8483; chemical reagent test strips G01N33/4875, G01N33/52
• CPC Class Codes: A61B 5/150419 comprising means for capillary action
• CPC Class Codes: A61B 5/150435 Specific design of proximal end
• CPC Class Codes: A61B 5/150503 Single-ended needles hollow piercing element tip design A61B5/150396, needle sets for catheters A61M25/06, needles for bringing media into the body A61M5/32
• CPC Class Codes: A61B 5/1519 comprising driving means, e.g. a spring, for propelling the piercing unit
• CPC Class Codes: A61B 5/157 Devices characterised by integrated means for measuring characteristics of blood
• CPC Class Codes: B01L 2200/027 for microfluidic devices
• CPC Class Codes: B01L 2300/0825 Test strips
• CPC Class Codes: B01L 2300/0838 Capillaries
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 2400/0633 with moving parts
• CPC Class Codes: B01L 3/5023 with a sample being transported to, and subsequently stored in an absorbent for analysis
• CPC Class Codes: B01L 3/502738 characterised by integrated valves microvalves F16K99/0001
• CPC Class Codes: Y10T 436/2575 Volumetric liquid transfer

Abstract

The test unit for analyzing body fluids such as blood comprises a collecting element which has a microfluidic collecting area for the body fluid, and a test element which can be brought into fluidic connection with the collecting area by deflecting a transfer part of the collecting element in order to transfer body fluid. The transfer part is pre-tensioned against a holding-down device and the deflection of the transfer part towards the test element can be triggered by releasing the holding-down device.

Claims

1. A test unit for analyzing body fluids such as blood, comprising:

a collecting element which has a microfluidic collecting area for a body fluid in the form of a semi-open channel; and

,

a test element configured to be brought into fluidic connection, with the collecting, area by deflection of a transfer part of the collecting element in order to transfer the body fluid,

wherein the transfer part is pre-tensioned against a holding-down device and the deflection of the transfer part towards the test element is triggered by releasing the holding-down device.

2. The test unit in claim 1 wherein the collecting area extends at least partially over the transfer part, and the collecting area and the test element are physically separated at a distance from one another before the deflection and the collecting area and the test element are in contact with one another after deflection.

3. The test unit in claim 1 wherein the transfer part is attached to the collecting element with a pre-bend.

4. The test unit in claim 3 wherein the pre-bend is a bending arm.

5. The test unit in claim 1 wherein the transfer part can be deflected with, a bending deformation by the action of internal stresses and/or surface tensions.

6. The test unit in claim 5 wherein the transfer part has a bending stress which causes the deflection due to a different surface treatment on different sides.

7. The test unit in claim 5 wherein the transfer part can be deflected due to different material layers like a bimetallic strip.

8. The test unit in claim 1 wherein the transfer part is formed from a flat substrate by an etching process where different etching depths on different sides of the transfer part result in inner bending stresses in the transfer part.

9. The test unit in claim 1 wherein the transfer part can be deflected by means of plastic deformation.

10. The test unit in claim 1 wherein the collecting element has a lancing member for insertion into a body part and the collecting area can be supplied with body fluid via the puncture.

11. The test unit in claim 1 wherein the holding-down device can be formed by a severable bridge of material between the collecting element and the transfer part, and that the deflection of the transfer part can be triggered by cutting through the bridge of material.

12. The test unit in claim 1 wherein the collecting element and the holding-down device are formed in one piece from a flat material in particular a sheet of high-grade steel where the holding-down device is formed by at least one severable cross-piece.

13. The test unit in claim 1 wherein the holding-down device is formed by an adhesive strip or a laminate mounted on the collecting element which stretches over a section of the transfer part.

14. The test unit in claim 1 wherein the test element in the initial state is preferably arranged on the collecting element at a preset distance from the transfer part by means of a spacer.

15. The test unit in claim 1 wherein the collecting element and the transfer part form a constructional unit that is intended to be a disposable single-use product.

16. The test unit in claim 1 wherein the transfer part in the contact state engages with the test element while maintaining a preset contact angle.

17. The test unit in claim 1 wherein the test element has a reagent field, to which body fluid can be applied through an opening of the collecting area.

18. A test system for analyzing body fluids such as blood, comprising:

a device in which at least one collecting element can be used in order to detect an analyte in a body fluid;

a collecting element which has a microfluidic collecting area for the body fluid in the form of a semi-open channel; and

,

a test element configured to be brought into fluidic connection with the collecting area by deflecting a transfer part of the collecting element in order to transfer body fluid;

wherein the transfer part is pretensioned against a holding-down device on the collecting element where the deflection can be triggered by releasing the holding-down device by means of a trigger in the device.

19. The test system in claim 18, wherein the trigger is formed by a serving unit that operates without contact and in particular a laser.

20. The test system in claim 18, wherein the trigger has a mechanically active cutting means.

21. The test system in claim 18, wherein the trigger is formed by a thermal actuator.

22. The test system in claim 18, wherein the test element is handled independently of the collecting element.

23. A test unit for analyzing body fluids such as blood, comprising:

a collecting element that has a microfluidic collecting area configured as a semi-opened channel for collecting the body fluid;

a test element carried on the collecting element for analyzing the body fluid;

means for transfer pretensioned against a holding-down device to deflect the collecting element to transfer body fluid to the test element; and

,

means for triggering to release the holding-down device upon being triggered to allow deflection of the collecting element in order to transfer body fluid free from an external drive to deflect the collecting element.

24. A method for analyzing blood to determine blood glucose level, comprising:

pretensioning a transfer part of a collecting element against a holding-down device;

lancing a body part to provide access to blood;

collecting the blood in a semi-open channel microfluidic collection area;

triggering the holding-down device to release the holding-down device;

deflecting the collecting element free from use of an external drive to deflect the collecting element;

transferring the blood from the collection area to a test element;

analyzing the blood by the test element to determine blood glucose level.