SENSOR ELEMENTS FOR DETECTING AN ANALYTE IN A BODY FLUID SAMPLE AS WELL AS METHODS OF MAKING THE SAME

• US 20150099954A1
• Filed: 12/10/2014
• Published: 04/09/2015
• Est. Priority Date: 06/29/2012
• Status: Active Application

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Roche Diagnostics Operations Incorporated (Roche Holding AG)
• Inventors: Kotzan, Holger, Achmann, Sabine, Mueller, Ulrich, Strasser, Monika, Wieder, Herbert
• Application Number:
  US14/566,033
• Publication Number:
  US 20150099954A1
• Time in Patent Office: Days
• US Class Current: 600/345
• 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 5/1468 using chemical or electrochemical methods, e.g. by polarographic means A61B5/1486 takes precedence
• CPC Class Codes: A61B 5/1473 invasive, e.g. introduced into the body by a catheter A61B5/1482 takes precedence

Abstract

Sensor elements are provided for determining at least one analyte concentration in a body fluid. The sensor elements are at least partially implantable into a body tissue and have a substrate and at least two electrodes. One electrode is a working electrode having at least one conductive pad applied to the substrate and at least one electrically conductive sensor material is applied to the conductive pad that includes at least one detector substance adapted to perform an electrically detectable electrochemical detection reaction with the analyte. Another electrode is a counter electrode having at least one counter electrode conductive pad applied to the substrate. The sensor elements also include at least one electrically insulating material that surrounds at least the counter electrode on all sides, where a height of the electrically insulating material at least equals a height of the counter electrode conductive pad.

Claims

1. A sensor element for determining concentration of at least one analyte in a body fluid, wherein the sensor element is at least partially implantable into a body tissue, the sensor element comprising:

a substrate;

at least two electrodes, wherein the at least two electrodes comprise at least one working electrode and at least one counter electrode, wherein the working electrode comprises at least one conductive pad applied to the substrate and having at least one electrically conductive working electrode sensor material applied to the at least one conductive pad, wherein the electrically conductive working electrode sensor material comprises at least one detector substance adapted to perform an electrically detectable electrochemical detection reaction with the analyte, and wherein the counter electrode comprises at least one counter electrode conductive pad applied to the substrate; and

at least one electrically insulating material, wherein the electrically insulating material surrounds the at least one counter electrode on all sides, and wherein a height of the electrically insulating material at least equals a height of the at least one counter electrode conductive pad.

2. The sensor element of claim 1, wherein the electrically insulating material forms at least one layer having at least one opening, and wherein the counter electrode conductive pad is located at least partially inside the opening.

3. The sensor element of claim 1, wherein the electrically insulating material covers an edge portion of the counter electrode conductive pad.

4. The sensor element of claim 1 further comprising a plurality of working electrodes.

5. The sensor element of claim 1, wherein the at least one counter electrode further comprises at least one electrically conductive counter electrode material that at least partially covers the counter electrode conductive pad.

6. The sensor element of claim 5, wherein the height of the electrically insulating material at least equals the height of the electrically conductive counter electrode material.

7. The sensor element of claim 1, wherein the at least one counter electrode further comprises at least one electron transfer interface, wherein the electron transfer interface, in an implanted state of the sensor element, is in contact with the body fluid, and wherein the height of the electrically insulating material at least equals a height of the electron transfer interface.

8. The sensor element of claim 1, wherein the electrically insulating material surrounds the electrically conductive working electrode sensor material on all sides, and wherein the height of the electrically insulating material at least equals a height of the electrically conductive working electrode sensor material.

9. The sensor element of claim 1, wherein the at least one counter electrode further comprises at least one electrically conductive counter electrode material comprising at least one counter electrode redox material adapted to perform at least one redox reaction, wherein the electrically insulating material surrounds the electrically conductive counter electrode material on all sides, and wherein the height of the electrically insulating material at least equals a height of the electrically conductive counter electrode material.

10. The sensor element of claim 1 further comprising at least one reference electrode comprising at least one reference electrode conductive pad and at least one electrically conductive reference electrode material, wherein the electrically conductive reference electrode material comprises at least one reference redox material providing a known redox potential.

11. The sensor element of claim 10, wherein the electrically insulating material surrounds the electrically conductive reference electrode material on all sides, and wherein the height of the electrically insulating material at least equals a height of the electrically conductive reference electrode material.

12. The sensor element of claim 1, wherein the at least one working electrode and the at least one counter electrode are applied to opposing surfaces of the substrate.

13. The sensor element of claim 12, wherein a projection of the at least one working electrode into a plane of the at least one counter electrode is overlapped by the at least one counter electrode.

14. The sensor element of claim 1, wherein projections of the at least one working electrode and the at least one counter electrode into a common plane are arranged essentially symmetrically with respect to at least one axis of symmetry.

15. The sensor element of claim 1, wherein the substrate has an elongated shape having an axis of longitudinal extension, and wherein, in a direction perpendicular to the axis of longitudinal extension, at least one of the at least one working electrode and the at least one counter electrode are equally spaced apart from at least two lateral edges of the substrate.

16. The sensor element of claim 1, wherein the sensor element comprises at least two counter electrodes arranged on opposing sides of the at least one working electrode, wherein the at least two counter electrodes are substantially equally spaced apart from the at least one working electrode.