Subcutaneous Glucose Electrode

• US 20070151869A1
• Filed: 03/02/2007
• Published: 07/05/2007
• Est. Priority Date: 03/04/1991
• Status: Active Grant

• Current Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Inventors: Heller, Adam, Pishklo, Michael
• Granted Patent: US 8,588,881 B2
• Time in Patent Office: Days
• US Class Current: 205/792
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1486 using enzyme electrodes, e.g. with immobilised oxidase
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: C12Q 1/006 for glucose
• CPC Class Codes: C12Q 1/54 involving glucose or galactose
• CPC Class Codes: Y10S 435/817 Enzyme or microbe electrode
• CPC Class Codes: Y10S 435/917 Aspergillus niger
• CPC Class Codes: Y10S 435/962 Prevention or removal of interfering materials or reactants or other treatment to enhance results, e.g. determining or preventing nonspecific binding

Abstract

A small diameter flexible electrode designed for subcutaneous in vivo amperometric monitoring of glucose is described. The electrode is designed to allow “one-point” in vivo calibration, i.e., to have zero output current at zero glucose concentration, even in the presence of other electroreactive species of serum or blood. The electrode is preferably three or four-layered, with the layers serially deposited within a recess upon the tip of a polyamide insulated gold wire. A first glucose concentration-to-current transducing layer is overcoated with an electrically insulating and glucose flux limiting layer (second layer) on which, optionally, an immobilized interference-eliminating horseradish peroxidase based film is deposited (third layer). An outer (fourth) layer is biocompatible.

Claims

1. An analyte measurement system, comprising:

at least one sensor introducer;

a first electrochemical sensor having at least one electrode with analyte response enzyme thereon, the first electrochemical sensor coupleable to the at least one sensor introducer for positioning at least a portion of the first sensor in the body of a user;

a second electrochemical sensor having at least one electrode with analyte response enzyme thereon, the second electrochemical sensor coupleable to the at least one sensor introducer for positioning at least a portion of the second sensor in the body of a user; and

a device to compare signals obtained from the first and second sensors.

2. The system of claim 1 wherein the device is further configured to determine whether at least one of the signals from the first or second sensors is valid based on the comparison.

3. The system of claim 1 wherein at least one electrode of the one or more of the first sensor or the second sensor comprises gold, platinum, palladium, or carbon.

4. The system of claim 1 wherein one of the first electrochemical sensor or the second electrochemical sensor is calibrated using a blood sample.

5. The system of claim 1 wherein at least one of the first electrochemical sensor or the second electrochemical sensor is calibrated using single point calibration.

6. The system of claim 1 wherein the analyte is glucose.

7. The system of claim 1 wherein at least one of the first electrochemical sensor and the second electrochemical sensor is implanted in the body of the user.

8. The system of claim 7 wherein the at least one of the first electrochemical sensor and the second electrochemical sensor is implanted subcutaneously in the body of the user.

9. The system of claim 1 wherein at least the one electrode of at least one of the first electrochemical sensor or the second electrochemical sensor is implanted in the body of the user.

10. A method of analyte measurement, comprising:

positioning at least a portion of at least one electrode of a first electrochemical sensor having analyte response enzyme thereon, in fluid contact with body fluid;

positioning at least a portion of at least one electrode of a second electrochemical sensor having analyte response enzyme thereon, in fluid contact with body fluid; and

comparing signals obtained from the first and second sensors.

11. The method of claim 10 further including determining whether at least one of the signals from the first or second sensors is valid based on the comparison.

12. The method of claim 10 further including measuring the body fluid.

13. The method of claim 12 wherein the body fluid includes analyte.

14. The method of claim 12 wherein measuring includes detecting the presence of glucose.

15. The method of claim 10 further including calibrating at least one of the first electrochemical sensor or the second electrochemical sensor using a blood sample.

16. The method of claim 10 further including calibrating using single point calibration at least one of the first electrochemical sensor or the second electrochemical sensor.

17. The method of claim 10, wherein the first and second sensors are positioned at different areas of the body.

18. The method of claim 10, wherein the first and second sensors are positioned at substantially the same area of the body.