BIOSENSOR AND METHODS FOR MANUFACTURING

• US 20110186430A1
• Filed: 02/02/2010
• Published: 08/04/2011
• Est. Priority Date: 02/02/2010
• Status: Active Grant

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Roche Diagnostics Operations Incorporated (Roche Holding AG)
• Inventors: Sauers, Matthew Carlyle
• Granted Patent: US 8,721,850 B2
• Time in Patent Office: Days
• US Class Current: 204/403.14
• CPC Class Codes: C12Q 1/006 for glucose
• CPC Class Codes: G01N 27/3272 Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels optical biosensors G01N33/52
• CPC Class Codes: Y10T 29/49227 Insulator making

Abstract

A biosensor for detecting an analyte in a sample of body fluid and methods for manufacturing the biosensor are disclosed. In one embodiment, a biosensor includes at least two electrical conductors embedded within an electrically insulating test element body. The electrical conductors are exposed at two ends of the test element body and a reagent, for example a reagent adapted to test for blood glucose, is applied to one end. In one form, the test element body is cylindrical with a circular or non-circular cross-sectional shape. In other embodiments, the test elements are manufactured by a resin pultrusion process in which resin embedded with electrical conductors is dried or cured, shaped and cut into segments, and reagent applied to one end of each segment.

Claims

1. A biosensor adapted to detect an analyte in a body fluid sample, comprising:

a single-piece body with two end surfaces;

at least two electrical conductors embedded within the single-piece body and extending between the two end surfaces, the at least two electrical conductors being exposed at the two end surfaces to define exposed portions of the at least two electrical conductors; and

a reagent disposed on one of the end surfaces and on the exposed portions of the at least two electrical conductors.

2. The biosensor of claim 1, wherein the reagent is configured to electrochemically react with a body fluid sample applied to the reagent, and wherein the reagent is in electrical communication with the electrical conductors when the body fluid is applied to the reagent.

3. The biosensor of claim 1, wherein the single-piece body is electrically insulating.

4. The biosensor of claim 1, wherein the single-piece body includes a polymeric matrix.

5. The biosensor of claim 1, wherein the biosensor of claim 1 is formed by pultrusion.

6. The biosensor of claim 1, wherein one of the at least two electrical conductors is configured for operation as a working electrode and another of the at least two electrical conductors is configured for operation as a counter electrode.

7. The biosensor of claim 1, wherein the single-piece body is a cylinder with a cross-sectional shape, and wherein the cross-sectional shape defines a height and a width that are approximately equal.

8. The biosensor of claim 1, wherein the single-piece body has a cross-sectional shape generally comprising of one of the shapes selected from the group consisting of circular, ovoid, elliptical, hexagonal, square, rectangular, pentagonal, octagonal and triangular.

9. The biosensor of claim 1, wherein the single-piece body has a regular or irregular polygonal cross-sectional shape.

10. The biosensor of claim 1, wherein the electrical conductors comprise copper wire, and a layer of metal selected from the group consisting of gold and palladium is disposed between the exposed portions of the at least two electrical conductors and the reagent.

11. The biosensor of claim 1, wherein the reagent comprises at least one enzyme adapted to test for blood glucose.

12. The biosensor of claim 11, wherein the at least one enzyme is selected from the group consisting of glucose dehydrogenase and glucose oxidase.

13. A system for detecting an analyte in a sample of body fluid, comprising:

a test element comprising a single-piece test element body with two end surfaces, at least two electrical conductors embedded within the test element body and extending between the two end surfaces, the at least two electrical conductors being exposed at the two end surfaces to define exposed portions of the at least two electrical conductors, a reagent being disposed on one of the end surfaces and on the exposed portions of the at least two electrical conductors at said one end; and

a test meter comprising a receptacle configured to receive the test element, the receptacle including at least two electrical connectors adapted to electrically connect with the electrical conductors when the test element is inserted into the receptacle.

14. The system of claim 13, wherein the electrical connectors connect with the surface of the test element in a non-sliding manner.

15. The system of claim 13, wherein the electrical connectors slide at most one-half millimeters (0.5 mm) across the surface of the test element as the test element is connected to the test meter

16. The system of claim 13, wherein the reagent comprises at least one enzyme adapted to test for blood glucose.

17. The system of claim 13, wherein the test element has an outer surface comprising at least one detent, and wherein the receptacle comprises at least one retention clip corresponding to each at least one detent and configured to register with the at least one detent in order to retain the test element within the receptacle.

18. The system of claim 13, the test element having an outer surface comprising a longitudinal recess, and the receptacle comprising one or more protrusions configured to engage the recess, wherein the rotational orientation for proper insertion of the test element into the receptacle ensuring electrical connection between the electrical conductors and the electrical connectors is determined by the engagement of the one or more protrusions with the recess.

19. The system of claim 13, wherein the receptacle is configured to receive the test element in first and second orientations, the first orientation being different from the second orientation, and wherein the function of the at least two test element electrical conductors when then test element is connected to the test meter in the first orientation is different from the function of the at least two test element electrical conductors when the test element is connected to the test meter in the second orientation.

20. The system of claim 19, wherein the at least two electrical conductors include a first electrical conductor, and wherein the first electrical conductor functions as a working electrode when the test element is connected to the test meter in the first orientation, and wherein the first electrical conductor functions as a counter electrode when connected to the test meter in the second orientation.

21. The system of claim 13, wherein the receptacle is configured to receive the test element in first and second orientations, the first orientation being different from the second orientation, and wherein the function of the at least two test meter electrical connectors when then test element is connected to the test meter in the first orientation is different from the function of the at least two test meter electrical connectors when the test element is connected to the test meter in the second orientation.

22. The system of claim 21, wherein the test element includes a feature detectable by the test meter, and wherein the test meter detects the orientation of the test element by detecting the location of the test element feature.

23. The system of claim 22, wherein the test element feature includes the at least two test elements electrical conductor comprising different materials.

24. The system of claim 23, wherein the test element includes a plurality of potential electrical conductor locations, and the feature includes the absence of a test element electrical conductor in at least one of the potential electrical conductor locations.

25. A system for detecting an analyte in a sample of body fluid, comprising:

a test element with a reagent, a working electrode, and a counter electrode, wherein the reagent contacts at least one electrode; and

a test meter with an electrical connector and a receptacle, the receptacle being configured to receive the test element in first and second orientations, the electrical connector contacting the working electrode in the first orientation and contacting the counter electrode in the second orientation, the electrical connector functioning as a working electrode when the test element is connected to the test meter in the first orientation, and the electrical connector functioning as a counter electrode when the test element is connected to the test meter in the second orientation.

26. A system for detecting an analyte in a sample of body fluid, comprising:

a test element with a conductor and a reagent disposed on the conductor; and

a test meter with a working electrode connector, a counter electrode connector, and a receptacle, the receptacle being configured to receive the test element in first and second orientations, the test element conductor contacting the working electrode connector in the first orientation and contacting the counter electrode connector in the second orientation, the test element conductor functioning as a working electrode when the test element is connected to the test meter in the first orientation, and the test element conductor functioning as a counter electrode when the test element is connected to the test meter in the second orientation.

27. A method for manufacturing a plurality of test elements adapted to detect an analyte in a sample of body fluid, the method comprising the acts of:

moving at least two electrical conductors through a resin;

drying or curing the resin;

shaping the resin;

cutting the shaped resin into segments; and

applying a reagent to one end of the at least two electrical conductors in each segment.

28. The method of claim 27, further comprising:

cutting the at least two electrical conductors and the resin into a plurality of segments after the curing; and

arranging the segments adjacent one another before the applying.

29. The method of claim 27, wherein the applying a reagent includes applying a reagent comprising at least one enzyme adapted to test for blood glucose.

30. The method of claim 27, wherein the shaping includes shaping the resin to have a generally continuous external surface that provides a cross-sectional shape generally comprising of one of the shapes selected from the group consisting of circular, ovoid, elliptical, hexagonal, square, rectangular, pentagonal, octagonal and triangular.

31. The method of claim 27, wherein the shaping includes shaping the resin to have a generally continuous external surface that provides a regular or irregular polygonal cross-sectional shape.

32. The method of claim 27, wherein the shaping includes shaping the resin to have one or more of grooves, scores, and detents along the length of the resin.