Electrochemical sensor

• US 20030217919A1
• Filed: 05/07/2003
• Published: 11/27/2003
• Est. Priority Date: 05/21/2002
• Status: Active Grant

• Current Assignee: Tanita Corporation (Tanita)
• Original Assignee: Tanita Corporation (Tanita)
• Inventors: Uchiyama, Shunichi, Yajima, Tatsuhiko, Harima, Shinichi
• Granted Patent: US 7,179,354 B2
• Time in Patent Office: Days
• US Class Current: 204/412
• CPC Class Codes: G01N 27/301 Reference electrodes
• CPC Class Codes: G01N 27/302 pH sensitive, e.g. quinhydron, antimony or hydrogen electrodes ion selective electrodes G01N27/333, glass electrodes G01N27/36
• CPC Class Codes: G01N 27/3335 the membrane containing at least one organic component G01N27/3271 takes precedence; aspects concerning the enzyme reagent in enzyme electrodes C12Q1/001
• CPC Class Codes: G01N 27/401 Salt-bridge leaks; Liquid junctions
• CPC Class Codes: G01N 27/4035 Combination of a single ion-sensing electrode and a single reference electrode G01N27/406 and G01N27/413 take precedence
• CPC Class Codes: G01N 27/4167 pH electrodes therefor G01N27/302, G01N27/36
• CPC Class Codes: G01N 27/4168 Oxidation-reduction potential, e.g. for chlorination of water water analysis G01N33/18

Abstract

Disclosed is an electrochemical sensor comprising a work electrode and a reference electrode, said sensor adapted to measure the characteristics of a liquid under test, based on the relative electric potential difference and electric current between the work electrode and the reference electrode both immersed in the liquid under test, said work electrode comprising a substrate that reacts to the liquid under test for generating an electric potential according to the concentration of the liquid under test, and said reference electrode comprising a substrate that reacts to the liquid under test for generating a fixed electric potential. According to the present invention, at least one of the work electrode and the reference electrode comprises said substrate coated with a function film for serving to generate the electric potential through the intervention of the film between said substrate and the liquid under test.

Claims

1. An electrochemical sensor comprising a work electrode and a reference electrode, said sensor adapted to measure the characteristics of a liquid under test, based on the relative electric potential difference and electric current between the work electrode and the reference electrode both immersed in the liquid under test, said work electrode comprising a substrate that reacts to the liquid under test for generating an electric potential according to the concentration of the liquid under test, and said reference electrode comprising a substrate that reacts to the liquid under test for generating a fixed electric potential, wherein

at least one of the work electrode and the reference electrode comprises said substrate coated with a function film for serving to generate the electric potential through the intervention of the film between said substrate and the liquid under test.

2. An electrochemical sensor comprising a work electrode and a reference electrode, said sensor adapted to measure the characteristics of a liquid under test, based on the relative electric potential difference and electric current between the work electrode and the reference electrode both immersed in the liquid under test, said work electrode comprising a substrate formed from platinum, gold, platinum black, etc., and said reference electrode comprising a substrate formed from silver coated with silver chloride film or a substrate formed from gold, wherein

said reference electrode comprises said substrate coated with a function film for serving to generate the electric potential through the intervention of the film between said substrate and the liquid under test.

3. An electrochemical sensor according to claim 2 wherein said reference electrode comprises said substrate formed from silver coated with silver chloride film and a salt bridge retaining film provided on said substrate as said function film.

4. An electrochemical sensor according to claim 2 wherein said reference electrode comprises said gold substrate and a plasma polymerized film having selective material non-transmission capability provided on said gold substrate as said function film, said plasma polymerized film consisting of at least one of aromatic compound, fluorinated compound, alcohol compound, etc.

5. An electrochemical sensor according to claim 2 wherein said reference electrode comprises said gold substrate and a basic solution immersion film provided on said gold substrate as said function film by immersing the substrate in the basic solution such as sodium hydroxide, potassium hydroxide, etc.

6. An electrochemical sensor according to claim 3 wherein said work electrode comprises said substrate formed from platinum, gold, platinum black, etc., and a plasma polymerized film having selective material transmission capability provided on said substrate, said plasma polymerized film consisting of at least one of aromatic compound, fluorinated compound, alcohol compound, etc.

7. An electrochemical sensor according to claim 4 wherein said work electrode comprises said substrate formed from platinum, gold, platinum black, etc., and a plasma polymerized film having selective material transmission capability provided on said substrate, said plasma polymerized film consisting of at least one of aromatic compound, fluorinated compound, alcohol compound, etc.

8. An electrochemical sensor according to claim 5 wherein said work electrode comprises said substrate formed from platinum, gold, platinum black, etc., and a plasma polymerized film having selective material transmission capability provided on said substrate, said plasma polymerized film consisting of at least one of aromatic compound, fluorinated compound, alcohol compound, etc.

9. An electrochemical sensor according to claim 2 wherein said work electrode comprises said substrate formed from platinum, gold, platinum black, etc., and a plasma polymerized film having selective material transmission capability provided on said substrate, said plasma polymerized film consisting of at least one of aromatic compound, fluorinated compound, alcohol compound, etc.

10. An electrochemical sensor according to claim 6 wherein said selective material transmission capability for said plasma polymerized film of the work electrode provides selective transmission of hydrogen ion.

11. An electrochemical sensor according to claim 7 wherein said selective material transmission capability for said plasma polymerized film of the work electrode provides selective transmission of hydrogen ion.

12. An electrochemical sensor according to claim 8 wherein said selective material transmission capability for said plasma polymerized film of the work electrode provides selective transmission of hydrogen ion.

13. An electrochemical sensor according to claim 9 wherein said selective material transmission capability for said plasma polymerized film of the work electrode provides selective transmission of hydrogen ion.

14. An electrochemical sensor according to claim 6 wherein said work electrode and said reference electrode are coated with a fixed hydrophobic film consisting of alkane polymer and annular olefin polymer.

15. An electrochemical sensor according to claim 3 wherein said work electrode and said reference electrode are coated with a fixed hydrophobic film consisting of alkane polymer and annular olefin polymer.

16. An electrochemical sensor according to claim 7 wherein said work electrode and said reference electrode are coated with a fixed hydrophobic film consisting of alkane polymer and annular olefin polymer.

17. An electrochemical sensor according to claim 4 wherein said work electrode and said reference electrode are coated with a fixed hydrophobic film consisting of alkane polymer and annular olefin polymer.

18. An electrochemical sensor according to claim 8 wherein said work electrode and said reference electrode are coated with a fixed hydrophobic film consisting of alkane polymer and annular olefin polymer.

19. An electrochemical sensor according to claim 5 wherein said work electrode and said reference electrode are coated with a fixed hydrophobic film consisting of alkane polymer and annular olefin polymer.

20. An electrochemical sensor according to claim 9 wherein said work electrode and said reference electrode are coated with a fixed hydrophobic film consisting of alkane polymer and annular olefin polymer.

21. An electrochemical sensor according to claim 2 wherein said work electrode and said reference electrode are coated with a fixed hydrophobic film consisting of alkane polymer and annular olefin polymer.

22. An electrochemical sensor according to claim 21 wherein said work electrode and said reference electrode are integrally assembled, but insulated from each other.

23. An electrochemical sensor according to claim 2 wherein said work electrode and said reference electrode are integrally assembled, but insulated from each other.

24. An electrochemical sensor according to claim 3 wherein said salt bridge retaining film is a salt bridge crystal film formed by crystallization of salt bridge of potassium chloride, sodium chloride, etc.

25. An electrochemical sensor according to claim 3 wherein said salt bridge retaining film is a perfluoroalkylsulfonic acid film impregnated with salt bridge of potassium chloride, sodium chloride, etc.

26. An electrochemical sensor according to claim 24 wherein said salt bridge is a mixture to which silver chloride is further added.

27. An electrochemical sensor according to claim 25 wherein said salt bridge is a mixture to which silver chloride is further added.