Particle-containing membrane and particulate electrode for analyte sensors

• US 8,560,039 B2
• Filed: 09/17/2009
• Issued: 10/15/2013
• Est. Priority Date: 09/19/2008
• Status: Active Grant

• Current Assignee: DexCom Incorporated
• Original Assignee: DexCom Incorporated
• Inventors: Simpson, Peter C., Boock, Robert J., Wightlin, Matthew, Shults, Mark C.
• Primary Examiner(s): Mallari, Patricia
• Assistant Examiner(s): D'ANGELO, MICHAEL J
• Application Number:
  US12/562,011
• Publication Number:
  US 20100076283A1
• Time in Patent Office: 1,489 Days
• Field of Search: 600/309, 600/316, 600345-347, 600/365, 435/4, 435/14, 436/68, 422/50, 422420-429, 20440301-40315, 702/23, 604 64- 66, 606/167, 606181-183
• US Class Current: 600/347
• CPC Class Codes: A61B 2562/028 Microscale sensors, e.g. electromechanical sensors [MEMS]
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/1473 invasive, e.g. introduced into the body by a catheter A61B5/1482 takes precedence
• 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: A61B 5/6848 Needles

Abstract

Systems and methods of use involving sensors having a particle-containing domain are provided for continuous analyte measurement in a host. In some embodiments, a continuous analyte measurement system is configured to be wholly, transcutaneously, intravascularly or extracorporeally implanted.

Claims

1. A sensor system for measurement of a species in a host, the sensor system comprising:

an electrode configured for implantation in a host, the electrode comprising an electroactive surface;

a membrane disposed over the electrode, the membrane comprising a particle-containing domain, wherein the particle-containing domain comprises a sensor element configured to measure a concentration of a first species, wherein the sensor element comprises a conductive component comprising a plurality of conductive particles; and

sensor electronics configured to generate a signal associated with a concentration of the species in the host.

2. The sensor system of claim 1, wherein the membrane further comprises an enzyme-containing domain located adjacent to the particle-containing domain.

3. The sensor system of claim 1, wherein the membrane further comprises an oxygen permeable domain located between the electroactive surface and the particle-containing domain.

4. The sensor system of claim 1, wherein the electroactive surface is configured for generating oxygen.

5. The sensor system of claim 1, wherein the particle-containing domain is a first sensor element configured to measure a concentration of a first species, and wherein the electrode is a second sensor element configured to measure a concentration of a second species.

6. The sensor system of claim 5, wherein the first species and the second species each comprise at least one of an analyte or a drug.

7. The sensor system of claim 5, wherein the particle-containing domain substantially reduces flow therethrough of at least one of the first species or the second species.

8. The sensor system of claim 5, wherein the sensor electronics are configured to apply a first bias potential to the first sensor element and to apply a second bias potential to the second sensor element, and wherein the first bias potential and the second bias potential are different.

9. The sensor system of claim 1, wherein the particle-containing domain comprises a conductive particle concentration that is sufficient for the particle-containing domain to function as a conductive film.

10. The sensor system of claim 1, wherein the particle-containing domain comprises hydrophilic and hydrophobic regions.

11. The sensor system of claim 1, wherein the particle-containing domain comprises polyurethane.

12. The sensor system of claim 1, wherein the particle-containing domain is powered.

13. The sensor system of claim 1, wherein the particle-containing domain has an oxygen diffusion coefficient greater than about 1×

10<sup>−

11</sup> m²/s.

14. The sensor system of claim 13, wherein the particle-containing domain has an oxygen diffusion coefficient greater than about 1×

10<sup>−

15</sup> m²/s in vivo.

15. The sensor system of claim 1, wherein the particle-containing domain has a glucose diffusion coefficient greater than about 1×

10<sup>−

10</sup> m²/s in vivo.

16. The sensor system of claim 1, wherein the conductive particles comprises platinum.

17. The sensor system of claim 1, wherein the particle-containing domain is formed of a conductive film.

18. The sensor system of claim 1, wherein the electrode is configured to measure a second species, wherein the first species and the second species comprise an analyte.

19. The sensor system of claim 18, wherein the analyte is glucose.