REAGENT STRIPE FOR TEST STRIP

• US 20090151864A1
• Filed: 02/20/2009
• Published: 06/18/2009
• Est. Priority Date: 06/20/2003
• Status: Active Grant

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Roche Operations Limited (Roche Holding AG)
• Inventors: Fritz, Michael, Zapf, Udo, Mosoiu, Dan, Burke, David W., Wilsey, Chris, Marquant, Michael
• Granted Patent: US 7,892,849 B2
• Time in Patent Office: Days
• US Class Current: 156/254
• CPC Class Codes: G01N 27/3271 Amperometric enzyme electrodes for analytes in body fluids, e.g. glucose in blood amperometry per se G01N27/49; aspects concerning the enzyme reagent C12Q1/001
• 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: G01N 33/558 using diffusion or migration of antigen or antibody immunochromatographic test strips G01N33/54387
• CPC Class Codes: Y10T 156/1059 Splitting sheet lamina in plane intermediate of faces
• CPC Class Codes: Y10T 156/1084 of continuous or running length bonded web

Abstract

A test strip having a small sample-receiving chamber on the order of less than 1 microliter. The inventive test strip includes a reagent layer that extends across the width of the test strip and also extends to the sample-receiving end, such that the edges of the reagent layer are aligned with the side and dose receiving edges of the test strip. The hydrophilic reagent extending to the dosing edge of the strip promotes wicking of the sample into the test strip. The end and side edges of the reagent layer are preferably formed as part of a cutting process that forms individual test strips from a larger web, which results in a smooth and thin reagent layer with a uniform thickness, substantially covering the entire floor of the sample-receiving chamber. The inventive mass production process helps improve the reproducibility of the quantity, location, thickness and other properties of the reagent layer, which in turn improves the accuracy of the test result.

Claims

1. A method of manufacturing a test strip having first and second sides, sample-receiving and meter insertion ends, and a central longitudinal axis extending between the two ends, the method comprising:

(a) providing a web of base substrate material having first and second web edges;

(b) forming an electrode set on the web;

(c) applying a stripe of reagent material to the web and covering at least one electrode of the electrode set with the stripe, the stripe being oriented substantially parallel to the first web edge; and

(d) cutting the test strip from the web, the cutting defining the first and second sides and the sample-receiving end of the test strip, wherein during the cutting a portion of the reagent stripe is cut and removed from the sample-receiving end of the test strip and further wherein the test strip comprises a reagent layer extending to the sample-receiving end and the first and second sides of the test strip.

2. The method of claim 1, further comprising, after step (c):

providing a web of spacing material having a cavity formed therein;

aligning the cavity with the central longitudinal axis of the test strip and then laminating the spacing material to the web of base substrate material; and

then performing step (d), wherein the cavity at least partially defines a sample-receiving chamber.

3. The method of claim 2, wherein an adhesive is used for the laminating of the web of spacing material to web of base substrate material.

4. The method claim 2, further comprising, after laminating the web of spacing layer material, aligning and then laminating a web of covering layer material over the web of spacing layer material.

5. The method of claim 4, wherein the covering layer material forms a vent opening that communicates with the sample-receiving chamber.

6. The method of claim 5, wherein the electrode set comprises a plurality of spaced electrode sets, the cavity comprises a plurality of spaced cavities, the central longitudinal axis comprises a plurality of spaced central longitudinal axes, and step (d) comprises making a plurality of cuts to form a plurality of the test strips.

7. The method of claim 6, wherein the cutting in step (d) further comprises forming sample-receiving openings on the sample-receiving ends, each sample-receiving opening leading into a respective cavity, the reagent layer of each test strip extending to the sample-receiving opening.

8. The method of claim 2, wherein the electrode set comprises a plurality of spaced electrode sets, the central longitudinal axis comprises a plurality of spaced central longitudinal axes;

and step (d) comprises making a plurality of cuts to form a plurality of test strips.

9. The method of claim 2, wherein the reagent stripe is deposited on the web of base substrate as a wet composition at a thickness of between about 50 μ

m and about 100 μ

m.

10. The method of claim 9, wherein the reagent stripe is deposited on the web of base substrate as a wet composition at a thickness of between about 60 μ

m and about 80 μ

m.

11. The method of claim 9, wherein the reagent stripe dries to a thickness of between about 3 μ

m and about 20 μ

m.

12. The method of claim 1, wherein step (c) comprises applying the reagent stripe by a slot-die coating process.

13. The method of claim 1, wherein the electrode set comprises a counter electrode and a working electrode, both of which are covered by the reagent stripe.

14. The method of claim 1, wherein the reagent stripe is continuous.

15. The method of claim 1, wherein the meter insertion end is located proximate the second edge of the web of base substrate material.