Analyte sensing biointerface

• US 8,060,174 B2
• Filed: 04/14/2006
• Issued: 11/15/2011
• Est. Priority Date: 04/15/2005
• Status: Active Grant

• Current Assignee: DexCom Incorporated
• Original Assignee: DexCom Incorporated
• Inventors: Simpson, Peter C., Brauker, James H.
• Primary Examiner(s): Mallari; Patricia
• Assistant Examiner(s): D'ANGELO, MICHAEL J
• Application Number:
  US11/404,929
• Publication Number:
  US 20060257996A1
• Time in Patent Office: 2,041 Days
• Field of Search: 600345-347, 600/365, 702/19
• US Class Current: 600/345
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• 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 5/14865 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: C12Q 1/001 Enzyme electrodes
• CPC Class Codes: C12Q 1/006 for glucose

Abstract

Disclosed herein is an analyte sensing biointerface that comprises a sensing electrode incorporated within a non-conductive matrix comprising a plurality of passageways extending through the matrix to the sensing electrode. Also disclosed herein are methods of manufacturing a sensing biointerface and methods of detecting an analyte within tissue of a host using an analyte sensing biointerface.

Claims

1. A glucose sensor configured for implantation in a host, comprising:

a biocompatible matrix comprising a plurality of passageways distributed throughout the biocompatible matrix, each of the plurality of passageways having interior surfaces;

a working electrode distributed throughout at least some of the interior surfaces of the plurality of passageways; and

a membrane disposed on the working electrode and distributed within the interior surfaces of the plurality of passageways, and wherein the membrane is configured to control a rate of diffusion of glucose through the membrane, and wherein the membrane comprises an enzyme configured to react with glucose to produce a species configured to electrochemically react at the working electrode.

2. The sensor of claim 1, further comprising a reference electrode disposed within the biocompatible matrix, wherein the reference electrode is located within the biocompatible matrix, and wherein at least a portion of the biocompatible matrix electrically insulates the reference electrode from the working electrode.

3. The sensor of claim 1, further comprising a reference electrode disposed on an exterior surface of the biocompatible matrix, wherein at least a portion of the biocompatible matrix electrically insulates the reference electrode from the working electrode.

4. The sensor of claim 1, further comprising a counter electrode disposed within the biocompatible matrix, wherein an electroactive surface of the counter electrode is located within the biocompatible matrix, and wherein at least a portion of the biocompatible matrix electrically insulates the counter electrode from the working electrode.

5. The sensor of claim 1, further comprising a counter electrode disposed on an exterior surface of the biocompatible matrix, wherein at least a portion of the biocompatible matrix electrically insulates the counter electrode from the working electrode.

6. The sensor of claim 1, further comprising a bioactive agent in the biocompatible matrix or in one or more of the plurality of passageways.

7. The sensor of claim 1, further comprising electronics electrically coupled to the working electrode, the electronics configured to measure a current flowing through the working electrode or a voltage of the working electrode, wherein the measured current or voltage is indicative of a concentration of glucose.

8. The sensor of claim 1, wherein the plurality of passageways are dimensioned to promote tissue in-growth.

9. The sensor of claim 1, wherein the plurality of passageways have a shortest dimension not less than 20 microns.

10. The sensor of claim 1, wherein the biocompatible matrix comprises a plurality of fibers.

11. The sensor of claim 10, wherein the fibers have a size of from about 1 micron to about 100 microns.

12. The sensor of claim 10, wherein the fibers are selected from the group consisting of woven fibers and non-woven fibers.

13. A lucose sensor configured for implantation in a host, comprising:

a biocompatible matrix comprising a plurality of fibers and a plurality of passageways having interior surfaces; and

a working electrode comprising at least one electroactive surface configured to detect an analyte concentration, the at least one electroactive surface located on a portion of an interior surface of at least one of the plurality of passageways, wherein at least one of the plurality of fibers comprises an electrode core that forms an electroactive surface of the working electrode.

14. The sensor of claim 13, wherein the working electrode has a membrane disposed thereon.

15. A glucose sensor configured for implantation in a host, comprising:

a biocompatible matrix comprising a plurality of passageways having interior surfaces; and

a working electrode comprising at least one electroactive surface configured to detect an analyte concentration, the at least one electroactive surface located on a portion of an interior surface of at least one of the plurality of passageways, wherein the at least one of the plurality of passageways extends through a conductive layer, wherein an interface formed between the interior surface of at least one passageway and the conductive layer forms an electroactive surface of the working electrode.

16. The sensor of claim 15, wherein the working electrode has a membrane disposed thereon.