Miniature multifunctional electrochemical sensor for simultaneous carbon dioxide-pH measurements

• US 3,905,889 A
• Filed: 11/01/1974
• Issued: 09/16/1975
• Est. Priority Date: 11/01/1974
• Status: Expired due to Term

• Current Assignee: Oliver H. Leblanc Jr, Robert A. Macur, Willard T. Grubb
• Original Assignee: Oliver H. Leblanc Jr, Robert A. Macur, Willard T. Grubb
• Inventors: Macur, Robert A., LeBlanc, Oliver H. Jr., Grubb, Willard T.
• Primary Examiner(s): Kaplan, G. L.
• Application Number:
  US05/519,798
• Time in Patent Office: 319 Days
• Field of Search: 204/195P,195M,195L,195R,1T 128/2E,2.1E 324/29
• US Class Current: 204/414
• CPC Class Codes: G01N 27/4045 for gases other than oxygen

Abstract

A miniature probe contains a multifunctional electrochemical sensor which measures both the hydrogen ion activity or pH of samples and the carbon dioxide activity of samples. The miniature probe includes a carbon dioxide sensor. When the potential of one electrode in the probe is measured with respect to that of an external reference electrode, a pH sensor is provided.

Claims

1. A MINIATURE PROBBE CONTANING A HYDROGE ION SENSING ELECTRODE AND A CARBON DIOXIDE SENSOR WHICH COMPRISES A FLEXIBLE, ELONGATED ELECTRODE LEAD, THE ELECTRODE LEAD COMPRISING A METALLIC BASE MEMBER, AN ELECTROCHEMICALLY ACTIVE REGION SHOWING ELECTROCHEMICAL RESPONSE TO PH CHANGES ADHERING TIGHTLY TO AND IN ELECTRICAL CONTACT WITH ONE END PORTION OF THE BASE MEMBER OF THE ELECTRODE LEAD, AND ELECTRICAL INSULATION SURRONDING THE BASE MEMBER THEREBY FORMING A HYDROGEN ION SENSING ELECTRODE:

A SECOND METAL ELECTRODE LEAD SPACED FROM THE BASE MEMBER OF THE FIRST ELECTRODE LEAD BY THE A REGION OF SILVER AND SILVER HALIDE OTHER THAN FLUORIDE THEREON A REGION OF SILVER AND SILVER HALIDE OTHER THAN FLUORIDE THEREON, AN ELECTROLYTE CONTACTING BOTH THE ELECTROCHEMICALLY ACTIVE REGION AND AT LEAST THE SILVER AND SILVER HALIDE REGION OF THE SECOND ELECTRODE LEAD, AND AN OUTER SHEATH OF A HYDROGEN ION AND CARBON DIOXIDE PERMEABLE DIFFUSION BARRIER MATERIAL ENCAPSULATING THE ELECTROCHEMICALLY ACTIVE REGION, AT LEAST THE SILVER AND SILVER HALIDE REGION OF THE SECOND ELECTRODE LEAD, AND THE ELECTROLYTE THEREBY FORMING A CARBON DIOXIDE SENSOR, THE DIFFUSION BARRIER MATERIAL BEING A HYDROPHOBIC ELASTOMER POLYMER WITH A DIELECTRIC CONSTANT OF FROM 4 TO 12 CONTAINING A HYDROPHOBIC AND LIPOPHILIC H+ION CARRIER.

2. A miniature probe as in claim 1, in which the electrochemically active region showing response to pH changes is a metallic oxide selected from the class consisting of palladium oxide and iridium oxide.

3. A miniature probe as in claim 1, in which the electrolyte is an immobilized aqueous solution.

4. A miniature probe as in claim 1, in which the hydrophobic and lipophilic H+ ion carrier is p-octadecyloxy-m-chlorophenylhydrazone mesoxalonitrile.