Electrochemical Analyte Sensor

• US 20060118415A1
• Filed: 02/20/2006
• Published: 06/08/2006
• Est. Priority Date: 03/04/1998
• Status: Active Grant

• Current Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Inventors: Heller, Ephraim, Heller, Adam, Say, James, Gal, Yoram, Aria, Behrad, Plante, Phillip John, Vreeke, Mark S., Tomasco, Michael F.
• Granted Patent: US 7,996,054 B2
• Time in Patent Office: Days
• US Class Current: 204/403.10
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/14735 comprising an immobilised reagent
• CPC Class Codes: A61B 5/1486 using enzyme electrodes, e.g. with immobilised oxidase
• CPC Class Codes: A61B 5/14865 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors
• CPC Class Codes: C12Q 1/001 Enzyme electrodes
• CPC Class Codes: C12Q 1/006 for glucose

Abstract

An electrochemical analyte sensor having conductive traces on a substrate is used to determine a level of analyte in in vitro or in vivo analyte-containing fluids. The electrochemical analyte sensor includes a substrate and conductive material disposed on the substrate, the conductive material forming a working electrode. In some sensors, the conductive material is disposed in recessed channels formed in a surface of the sensor. An electron transfer agent and/or catalyst may be provided to facilitate the electrolysis of the analyte or of a second compound whose level depends on the level of the analyte. A potential is formed between the working electrode and a reference electrode or counter/reference electrode and the resulting current is a function of the concentration of the analyte in the fluid.

Claims

1. An electrochemical sensor comprising:

a substrate;

a first conductive material disposed on a surface of the substrate to form one or more working electrodes;

one or more contact pads in electrical contact with the one or more working electrodes;

a second conductive material disposed on a surface of the substrate to form a counter electrode, a reference electrode, or a counter-reference electrode;

a contact pad in electrical contact with the counter electrode, reference electrode or counter-reference electrode;

an enzyme disposed proximate to the working electrode; and

an analyte mass transport limiting layer disposed over at least a portion of the working electrode to limit transport of an analyte to the working electrode, wherein the portion of the working element having the analyte mass transport limiting layer is configured and arranged for subcutaneous implantation into the body of an animal for contact with body fluid of the animal.

2. The sensor of claim 1, wherein the second conductive material is the same as the first conductive material.

3. The sensor of claim 1, wherein the second conductive material is different from the first conductive material.

4. The sensor of claim 1, wherein the enzyme is non-leachably disposed proximate the working electrode.

5. The sensor of claim 1, further comprising an electron transfer agent disposed proximate the working electrode.

6. The senor of claim 5, wherein the electron transfer agent is non-leachably disposed proximate the working electrode.

7. An electrochemical sensor, comprising:

a substrate;

conductive material disposed on a surface of the substrate to form a plurality of traces, at least one of the traces forming a working electrode; and

an enzyme disposed proximate to the working electrode;

wherein at least two of conductive traces are separated on the surface of the substrate by 150 μ

m or less.

8. The sensor of claim 7, wherein the plurality of conductive traces are separated on the surface of the substrate by 50 μ

m or less.

9. The sensor of claim 7, wherein the sensor further comprises an analyte limiting layer proximate the working electrode.

10. The sensor of claim 7, wherein the enzyme is non-leachably disposed proximate the working electrode.

11. The sensor of claim 7, further comprising an electron transfer agent disposed proximate the working electrode.

12. The senor of claim 11, wherein the electron transfer agent is non-leachably disposed proximate the working electrode.

13. The sensor of claim 7, wherein the surface of the substrate comprises a wide portion and a narrow portion, the narrow portion being configured for implantation into a patient.

14. The sensor of claim 13, wherein the narrow portion has a width of about 0.5 mm or less.

15. An electrochemical sensor, comprising:

a substrate;

conductive material disposed on a surface of the substrate to form a plurality of traces, at least one of the traces forming a working electrode; and

an enzyme disposed proximate to the working electrode;

wherein the plurality of conductive traces are disposed on the surface of the substrate at a density, along a width of the substrate, of about 150 to 700 μ

m/trace or less.

16. The sensor of claim 15, wherein the density is 667 μ

m/trace or less.

17. The sensor of claim 15, wherein the surface of the substrate comprises a wide portion and a narrow portion, the narrow portion being configured for implantation into a patient.

18. The sensor of claim 17, further comprising an analyte mass transport limiting layer proximate the working electrode.

19. The sensor of claim 15, wherein the enzyme is non-leachably disposed proximate the working electrode.