ELECTROCHEMICAL TEST SENSOR

• US 20110056848A1
• Filed: 09/08/2010
• Published: 03/10/2011
• Est. Priority Date: 09/08/2009
• Status: Active Grant

• Current Assignee: Ascensia Diabetes Care Holdings AG (PHC Holdings Corporation)
• Original Assignee: Bayer Healthcare LLC (Bayer AG)
• Inventors: Fei, Jianfeng, Jiang, Hualin, Reynolds, Jeffery S., Wang, Yuan, Gifford, Raeann
• Granted Patent: US 9,034,172 B2
• Time in Patent Office: Days
• US Class Current: 205/792
• CPC Class Codes: G01N 27/3272 Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels optical biosensors G01N33/52

Abstract

An electrochemical test sensor for detecting the concentration of an analyte in a fluid sample. The electrochemical test sensor includes a housing that has a first end and a second opposing end. The housing includes an opening at the first end to receive a fluid test sample. An electrode assembly includes a substrate, a working electrode, a counter electrode and a reagent. The substrate has a first surface and an opposing second surface. The working electrode is disposed on the first surface of the substrate, and the counter electrode is disposed on the second surface of the substrate. The electrode assembly is positioned within the housing to define a reaction channel. The electrochemical test sensor may be used with a removable lancet mechanism or integrated within a lancet mechanism to form one integral unit.

Claims

1. An electrochemical test sensor for detecting the concentration of an analyte in a fluid sample, the electrochemical test sensor comprising:

a housing having a first end and a second opposing end, the housing including an opening at the first end to receive a fluid test sample; and

an electrode assembly including a substrate, a working electrode, a counter electrode and a reagent, the substrate having a first surface and an opposing second surface, the working electrode being disposed on the first surface of the substrate, the counter electrode being disposed on the second surface of the substrate, the electrode assembly being positioned within the housing to define a reaction channel.

2. The electrochemical test sensor of claim 1, wherein the electrode assembly extends across a width dimension of an interior of the housing to form a first capillary channel being exposed to the working electrode and a second capillary channel being exposed to the counter electrode.

3. The electrochemical test sensor of claim 2, wherein the electrode assembly includes first and second sides located between first and second surfaces, the first and second sides at one end being tapered toward each other.

4. The electrochemical test sensor of claim 2, wherein the first and second capillary channels are in communication with one another at the reaction channel.

5. The electrochemical test sensor of claim 1, further comprising at least one underfill electrode disposed on at least one of the first and second surfaces of the substrate.

6. The electrochemical test sensor of claim 5, wherein the at least one underfill electrode includes an underfill electrode located on the first and second surfaces of the substrate.

7. The electrochemical test sensor of claim 1, wherein a volume of the reaction channel is from about 0.1 μ

L to about 0.3 μ

L.

8. The electrochemical test sensor of claim 1, wherein a volume of the reaction channel is less than 0.5 μ

L.

9. The electrochemical test sensor of claim 1, wherein a volume of the reaction channel is less than 0.3 μ

L.

10. The electrochemical test sensor of claim 1, wherein a volume of the reaction channel is from about 0.1 μ

L to about 0.5 μ

L.

11. The electrochemical test sensor of claim 1, wherein the housing at a first end has a circular cross-sectional shape.

12. A method for determining the concentration of an analyte in a fluid sample with a test sensor, the method comprising:

providing an electrochemical test sensor including a housing and an electrode assembly, the housing having a first end and a second opposing end, the housing including an opening at the first end to receive a fluid test sample;

the electrode assembly including a substrate, a working electrode, a counter electrode and a reagent, the substrate having a first surface and an opposing second surface, the working electrode being disposed on the first surface of the substrate, the counter electrode being disposed on the second surface of the substrate, the electrode assembly being positioned within the housing to define a reaction channel;

providing the fluid sample to the reaction channel;

reacting the analyte of the fluid sample with the reagent to generate an electrical signal in the sensor in response to the presence of the analyte in the fluid sample; and

determining the analyte concentration using the electrical signal.

13. The method of claim 12, wherein the electrode assembly extends across a width dimension of an interior of the housing to form a first capillary channel being exposed to the working electrode and a second capillary channel being exposed to the counter electrode.

14. The method of claim 13, wherein the first and second capillary channels are in communication with one another at the reaction channel.

15. The method of claim 13, wherein the electrode assembly includes first and second sides located between first and second surfaces, the first and second sides at one end being tapered toward each other.

16. The method of claim 12, wherein a volume of the reaction channel is from about 0.1 μ

L to about 0.3 μ

L.

17. An integrated lancet/electrochemical test sensor assembly for detecting the concentration of an analyte in a fluid sample, the assembly comprising:

a housing having a first end and a second opposing end, the housing including an opening at the first end to receive a fluid test sample; and

an electrode assembly including a substrate, a working electrode, a counter electrode and a reagent, the substrate having a first surface and an opposing second surface, the working electrode being disposed on the first surface of the substrate, the counter electrode being disposed on the second surface of the substrate, the electrode assembly being positioned within the housing to define a reaction channel;

an integrated lancet extending from the tapered area and exposed outside of the opening, the lancet needle including a fluid channel therein configured to pass the fluid sample from an incision site to the tapered area via capillary action.

18. An electrochemical test sensor assembly for detecting the concentration of an analyte in a fluid sample, the electrochemical test sensor comprising:

a lancet mechanism including a hollow lancet adapter and a needle configured to flow the fluid sample therethrough;

a housing having a first end and a second opposed end, the second end coupled to the hollow lancet adapter, the housing including an opening at the first end to receive the fluid sample received from the lancet needle, the housing coupled to the lancet mechanism;

an electrode assembly including having a first surface and an opposed second surface, the electrode assembly including a working electrode disposed on the first surface of the substrate and a counter electrode disposed on the second surface of the substrate, the working and counter electrode having a tip proximal to the opening, wherein the electrode assembly is positioned within the housing and configured to define a reaction channel located between the opening of the housing and the tip of the electrode assembly.