Amperometric sensor electrodes

• US 9,541,519 B2
• Filed: 03/25/2010
• Issued: 01/10/2017
• Est. Priority Date: 10/18/2002
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Holker, James D., Shah, Rajiv, Hoss, Udo, Gottlieb, Rebecca K., Soundararajan, Gopikrishnan
• Primary Examiner(s): Hendricks, Keith
• Assistant Examiner(s): CARLSON, KOURTNEY SALZMAN
• Application Number:
  US12/731,567
• Publication Number:
  US 20100175992A1
• Time in Patent Office: 2,483 Days
• Field of Search: 20440301-40315, 205/777.5, 205/778, 205/792, 205/67, 205/69, 205/70, 205/72, 205/122
• US Class Current: 1/1
• CPC Class Codes: A61B 5/1486 using enzyme electrodes, e.g. with immobilised oxidase
• CPC Class Codes: C25D 1/10 Moulds; Masks; Masterforms
• CPC Class Codes: C25D 5/10 Electroplating with more than one layer of the same or of different metals for bearings C25D7/10
• CPC Class Codes: C25D 5/605 Surface topography of the layers, e.g. rough, dendritic or nodular layers
• CPC Class Codes: C25D 5/611 Smooth layers
• CPC Class Codes: C25D 5/623 Porosity of the layers
• CPC Class Codes: G01N 27/307 Disposable laminated or multilayered electrodes G01N27/3272 takes precedence
• CPC Class Codes: G01N 27/327 Biochemical electrodes , e.g. electrical or mechanical details for in vitro measurements
• CPC Class Codes: Y10T 428/12389 having variation in thickness
• CPC Class Codes: Y10T 428/12479 Porous [e.g., foamed, spongy, cracked, etc.]
• CPC Class Codes: Y10T 428/12493 Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
• CPC Class Codes: Y10T 428/12875 Platinum group metal-base component
• CPC Class Codes: Y10T 428/12889 Au-base component

Abstract

Embodiments of the invention provide electrochemical analyte sensors having elements designed to modulate their electrochemical reactions as well as methods for making and using such sensors.

Claims

1. An amperometric sensor electrode comprising a plurality of electrodeposited metal layers comprising:

(a) a base substrate comprising a polyimide;

(b) a first metal layer comprising gold or chrome disposed on the base substrate and having a first surface area and a first adhesion strength with the base substrate on which the first metal layer is disposed; and

(c) a second metal layer comprising platinum electrodeposited on the first metal layer, the second metal layer having a second surface area and a second adhesion strength with the first layer on which the second layer is electrodeposited, wherein the second surface area is greater than the first surface area and the second adhesion strength is greater than the first adhesion strength.

2. The electrode of claim 1, wherein the substrate comprises a geometric feature selected to increase the surface area of the electrodeposited second metal layer.

3. The electrode of claim 2, wherein the second metal layer comprises platinum black.

4. The electrode of claim 2, wherein the substrate comprises a porous substrate.

5. The electrode of claim 1, further comprising:

an analyte sensing layer disposed on the electrode, wherein the analyte sensing layer comprises a material that can detectably alter the electrical current at the electrode in the presence of an analyte;

an adhesion promoting layer disposed on the analyte sensing layer, wherein the adhesion promoting layer promotes the adhesion between the analyte sensing layer and an analyte modulating layer disposed on the analyte sensing layer; and

an analyte modulating layer disposed on the analyte sensing layer, wherein the analyte modulating layer modulates the diffusion of the analyte therethrough; and

a cover layer disposed on at least a portion of the analyte modulating layer;

wherein the cover layer further includes an aperture over at least a portion of the analyte modulating layer, and

the electrode, the analyte sensing layer, the adhesion promoting layer, the analyte modulating layer and the cover layer are configured to form an implantable electrochemical analyte sensor electrode.

6. The electrode of claim 5, wherein the analyte sensing layer comprises glucose oxidase or lactate oxidase.

7. The electrode of claim 5, wherein the electrode, the analyte sensing layer, the adhesion promoting layer, the analyte modulating layer and the cover layer are configured to form a glucose biosensor electrode.