Electrochemical electrode test strip and a process for preparation thereof

• US 20020003087A1
• Filed: 05/31/2001
• Published: 01/10/2002
• Est. Priority Date: 06/01/2000
• Status: Active Grant

• Current Assignee: Bioptik Technology, Inc.
• Original Assignee: Bioptik Technology, Inc.
• Inventors: Chih-hui, Lee
• Granted Patent: US 6,723,371 B2
• Time in Patent Office: Days
• US Class Current: 204/400
• CPC Class Codes: G01N 27/3272 Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels optical biosensors G01N33/52

Abstract

As embodied and broadly described herein, the invention provides an electrode test strip. The electrochemical electrode test strip comprises an insulating base plate, a electrode system on the base plate, a spacer which partially covers the electrode system and a channel trench with a constant width is formed thereof, a reactive film, and a cover on the spacer with an first opening thereof. Wherein the electrode system comprises at least a working electrode and a reference electrode, and the working electrode and the reference electrode is isolated. The reactive film contains at least on active species that can have a specific redox reaction with the analyte. The first opening exposes the channel trench, and two second openings are located at the two ends of the channel trench.

Claims

1. An electrode test strip for detecting an analyte concentration, comprising:

an insulating base plate;

an electrode system on the first surface of the insulating base plate, the electrode system comprises at least a working electrode and a reference electrode, wherein the working electrode and the reference electrode is isolated;

a spacer partially covering the first surface of the insulating base plate and the electrode system to expose first part of the electrode system, and a channel trench cross the spacer is formed therein to expose second part of the electrode system;

a reactive film in the channel trench, the reactive film contains at least one active species that can have a specific redox reaction with the analyte; and

a cover with a first opening on the spacer, wherein the first opening exposes the channel trench, and two second openings formed at the two ends of the channel trench.

2. The electrode test strip of claim 1, wherein the insulating base plate is selected from the group consisting of PC plate, polyvinylchloride plate, polyethylene terephthalate plate, glass fiber plate (FR-4), bakelite ceramics, ceramic plate (CEM-1), glass plate and polyester sulfone plate.

3. The electrode test strip of claim 1, wherein the area of the working electrode is arger than the area of the reference electrode.

4. The electrode test strip of claim 1, wherein the material of the electrode system is selected from the group consisting of carbon glue, silver glue, gold glue, carbon-silver glue, cooper glue, carbon-platinum glue, and a combination thereof.

5. The electrode test strip of claim 1, wherein the reactive film contain a hydrophilic polymer.

6. The electrode test strip of claim 5, wherein the polymer is selected from the group consisting of Polyvinyl Pyrrolidone, Polyethylene Glycol, gelatin, dextran, polyvinyl alcohol, methylcellulose, carboxymethyl cellulose, albumin, chitin and a combination thereof.

7. The electrode test strip of claim 1, wherein the reactive film contains an electron medium.

8. The electrode test strip of claim 7, wherein the electron medium includes potassium ferricyanide.

9. The electrode test strip of claim 1, wherein the reactive film contains a nonionic surfactant.

10. The electrode test strip of claim 9, wherein the nonionic surfactant is selected from the group consisting of Triton X-100, lecithins, phosphatidyl choline, oleic acid, cyclodextrin and polyoxyethylene glycerine fatty acid ester.

11. The electrode test strip of claim 1, wherein the reactive film contains a buffer solution.

12. The electrode test strip of claim 11, wherein the buffer reagent of the buffer solution is selected from the group consisting of citric acid, dipotassium phosphate, potassium phosphate, Tris and borate.

13. The electrode test strip of claim 1, wherein the active species includes an enzyme, a protein or a chemical.

14. The electrode test strip of claim 13, wherein the active species is fixed in the reactive film.

15. The electrode test strip of claim 1, wherein the diameter of the first opening is it least equal to the channel trench width.

16. The electrode test strip of claim 1 further comprises a nitrate fiber film on the channel trench and under the first opening.

17. The electrode test strip of claim 1, when one of the first and second openings serves as a sample inlet, the other two openings serves as gas outlets.

18. A method of manufacturing a electrode test strip, comprising the steps of:

offering an insulating base plate;

printing a layer of conductive films to be a cathode and an anode, the cathode and the anode are isolated;

forming a first spacer and a second spacer on the conductive films to expose two ends of the cathode and the anode, wherein a channel trench is formed between the first and the second spacer;

spreading a reagent solution on a bottom surface of the channel trench;

drying the reagent solution to form a reactive film in the channel trench; and

forming a cover with a first opening on the spacer, wherein the first opening is located on the channel trench and two second openings are surrounded by the insulating base plate, the first spacer, the second spacer and the cover.

19. The method of the claim 18, wherein the reagent solution comprises an active species, a polymer, an electron medium, a nonionic surfactant and a buffer solution.

20. The method of the claim 19, wherein the polymer is about 1-4wt %.

21. The method of the claim 19, wherein the polymer is selected from the group consisting of Polyvinyl Pyrrolidone, Polyethylene Glycol, gelatin, dextran, polyvinyl alcohol, methylcellulose, carboxymethyl cellulose, albumin, chitin and a combination thereof.

22. The method of the claim 19, wherein the electron medium is about 1-10 wt %.

23. The method of the claim 19, wherein the electron medium includes potassium ferricyanide.

24. The method of the claim 19, wherein the nonionic surfactant is less than about 0.3 wt %.

25. The method of the claim 19, wherein the nonionic surfactant is selected from the group consisting of Triton X-100, lecithins, phosphatidyl choline, oleic acid, cyclodextrin and polyoxyethylene glycerine fatty acid ester.

26. The method of the claim 19, wherein the buffer solution is about 83.7-98 wt %.

27. The method of the claim 19, wherein the buffer reagent of the buffer solution is a selected from the group consisting of citric acid, dipotassium phosphate, potassium phosphate, Tris and borate.

28. The method of the claim 19, wherein between the steps of drying the reagent solution and forming a cover further comprises a step of covering a nitrate fiber film on the channel trench.