Extended use planar sensors

• US 5,503,719 A
• Filed: 03/09/1994
• Issued: 04/02/1996
• Est. Priority Date: 04/09/1993
• Status: Expired due to Term

• Current Assignee: Novartis Ag
• Original Assignee: CIBA Vision Corporation (Bayer AG)
• Inventors: Edelman, Peter G., Flaherty, James E., Berger, Joseph, Foos, Joseph S.
• Primary Examiner(s): Bell, Bruce F.
• Application Number:
  US08/209,081
• Time in Patent Office: 755 Days
• Field of Search: 204/434, 204/413, 204/153.1
• US Class Current: 205/782.5
• CPC Class Codes: C08F 220/14 Methyl esters , e.g. methyl (meth)acrylate
• CPC Class Codes: G01N 27/404 Cells with anode, cathode and cell electrolyte on the same side of a permeable membrane which separates them from the sample fluid , e.g. Clark-type oxygen sensors
• CPC Class Codes: G01N 33/4925 measuring blood gas content, e.g. O2, CO2 , HCO3
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing
• CPC Class Codes: Y10T 29/5313 Means to assemble electrical device
• CPC Class Codes: Y10T 29/5317 Laminated device
• CPC Class Codes: Y10T 29/532 Conductor
• CPC Class Codes: Y10T 29/53204 Electrode

Abstract

A planar, solid-state electrochemical oxygen sensor having a substrate, conductive strips deposited on the substrate, and a dielectric layer insulating portions of the conductive strips except those portions which define a working electrode and at least one second electrode. The working electrode may be defined by an open printed region of the dielectric, or by a needle-punched or laser-burned hole or opening in the dielectric which exposes a small region of one of the conductive strips. A solid electrolyte contacting the electrodes is covered by a semipermeable membrane which may comprise an acrylonitrile butadiene copolymer or an acrylate-based copolymer. A sample chamber is defined by the membrane, a cover member, and a gasket therebetween, and has a volume of from about 1 to about 2 μl. The gasket is formulated from the highly cross-linked polymerization product of epichlorohydrin. All sensor components are selected such that a sensor operable for at least 2 days under normal conditions is produced.

Claims

1. A method for selecting an electrically-conductive material for use in an electrochemical sensor, comprising:

providing a sensor for electrochemical analysis, said sensor including an electrically-conductive material,

measuring the polarogram of said material to determine the shape of said polarogram in a set potential region within which said sensor is designed to operate, and

evaluating said polarogram in said set potential region to determine whether said polarogram exhibits a plateau, whereby the utility of said material is determined.

2. A method for evaluating the durability of an electrochemical sensor comprising:

providing a sensor for electrochemical analysis,

measuring the polarogram of said sensor to determine the shape of said polarogram in a set potential region within which said sensor is designed to operate, and

evaluating said polarogram in said set potential region to determine whether said polarogram exhibits a substantially flat current vs. voltage plot, whereby the durability of the sensor is determined.

3. A method for selecting an electrically-conductive material for use in an analytical sensor, comprising:

providing a sensor for electrochemical analysis, said sensor including an electrically-conductive material,

measuring the polarogram of said material to determine the shape of said polarogram in a set potential region within which said sensor is designed to operate, and

evaluating said polarogram in said set potential region to determine whether said polarogram exhibits a substantially flat current vs. voltage plot, whereby the utility of said material is determined.

4. A method for evaluating the durability of an electrochemical sensor, comprising:

providing a sensor for electrochemical analysis,

measuring the polarogram of said sensor to determine the shape of said polarogram in a set potential region within which said sensor operates, and

evaluating said polarogram in said set potential region to determine whether the voltage fluctuation varies outside a margin of error to assess the durability of said sensor.