Sensor with improved shelf life

• US 6,652,734 B1
• Filed: 09/19/2000
• Issued: 11/25/2003
• Est. Priority Date: 03/16/1999
• Status: Expired due to Fees

• Current Assignee: Lifescan Incorporated (Duv Holding Corporation)
• Original Assignee: Lifescan Incorporated (Duv Holding Corporation)
• Inventors: Chatelier, Ronald, Hodges, Alastair
• Primary Examiner(s): Warden, Sr., Robert J.
• Assistant Examiner(s): Olsen, Kaj K.
• Application Number:
  US09/664,688
• Time in Patent Office: 1,162 Days
• Field of Search: 204/403, 204/418, 204/280, 204/290.11, 204/403.01, 204/403.14, 205/777.5, 205/793, 427/58
• US Class Current: 205/777.5
• CPC Class Codes: A61B 5/14539 for measuring pH
• CPC Class Codes: A61B 5/1486 using enzyme electrodes, e.g. with immobilised oxidase
• CPC Class Codes: A61N 1/0476 Array electrodes (including any electrode arrangement with more than one electrode for at least one of the polarities)
• CPC Class Codes: A61N 1/0492 Patch electrodes A61N1/0412, A61N1/0428 take precedence
• CPC Class Codes: A61N 1/05 for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence
• CPC Class Codes: G01N 27/30 Electrodes, e.g. test electrodes; Half-cells G01N27/414 takes precedence
• CPC Class Codes: G01N 27/3271 Amperometric enzyme electrodes for analytes in body fluids, e.g. glucose in blood amperometry per se G01N27/49; aspects concerning the enzyme reagent C12Q1/001

Abstract

The present invention provides a metal electrode stabilised by a coating, the coating comprising a sulfur containing moiety in its molecular structure. The coating may also include a hydrophilic group and a spacer between the sulfur containing moiety and the hydrophilic group. Preferably, the sulfur containing moiety is selected from the group comprising thiol, disulfide and SO_x, and the hydrophilic group is selected from the group comprising hydroxyl, amine, carboxyl, carbonyl, oligo (ethylene oxide) chain, and zwitterionic species. Compounds useful in the present invention include 2-mercaptoethanol, 2-mercaptoethylamine, 3-mercaptopropionic acid, thiophene, 4-carboxythiophene, cysteine, homocysteine, and cystine.

Claims

1. A metal electrode stabilized by a coating, said coating comprising 3-carboxythiophene and adapted to increase a temporal stability of said electrode relative to a corresponding uncoated metal electrode, said coating further comprising an overcoating of a surfactant.

2. A method of sensing an analyte including the step of providing a metal electrode stabilized by a coating according to claim 1, and sensing an analyte.

3. A metal electrode according to claim 1, wherein said surfactant further comprises a hydrophilic group.

4. A method of preparing a metal electrode stabilized by a coating, including the step of contacting a metal electrode with a substance comprising 3-carboxythiophene, said method further comprising the step of overcoating the substance with a surfactant.

5. A method according to claim 4 wherein the surfactant and substance are applied simultaneously.

6. A method according to claim 4 wherein the surfactant is applied to the electrode subsequent to the application of the substance.

7. A method according to claim 4, wherein said coating is applied as a monolayer or multilayer on a surface of an electrode.

8. A method according to claim 4, wherein said substance is applied by deposition from a vapor phase.

9. A method according to claim 4, wherein said substance is applied by deposition from a liquid solution.

10. A method according to claim 4, wherein said substance is applied by a method selected from the group consisting of dipping, spraying, painting, and printing.

11. A method of sensing an analyte, said method comprising a step for preparing a metal electrode according to claim 4, and a step for sensing an analyte.