Electrochemical biosensor test strip, fabrication method thereof and electrochemical biosensor

• US 6,805,780 B1
• Filed: 10/05/2001
• Issued: 10/19/2004
• Est. Priority Date: 04/06/1999
• Status: Expired due to Term

• Current Assignee: Allmedicus Company Limited
• Original Assignee: Allmedicus Company Limited
• Inventors: Lee, Jinwoo, Ryu, Junoh
• Primary Examiner(s): Olsen, Kaj K.
• Application Number:
  US09/958,259
• Time in Patent Office: 1,110 Days
• Field of Search: 204/403.01, 204/403.14, 204/409, 204/192.2
• US Class Current: 204/403.01
• CPC Class Codes: G01N 27/3272 Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels optical biosensors G01N33/52
• CPC Class Codes: G01N 33/5438 Electrodes

Abstract

Electrochemical biosensor test strip, fabrication method thereof and electrochemical biosensor are disclosed. The electrochemical biosensor test strip is fabricated by cutting a groove in a first insulation base in the breadth direction, forming two electrodes parallel to length direction on the first insulation base by sputtering using shadow mask, fixing a reaction material comprising an enzyme which reacts an analyte and generates current corresponding to the concentration of analyte across the two electrodes on the groove of the insulation base, and affixing a cover to the first insulation base. The groove of the first insulation base and the cover make a capillary at the position where the reaction material is fixed. The fabrication method can lower the cost for fabricating the test strip by forming thin electrodes.

Claims

1. An electrochemical biosensor test strip, comprising:

a first insulating substrate having a groove in a widthwise direction;

a pair of electrodes parallel in a lengthwise direction across the groove on the first insulating substrate;

a reagent for reacting with an analyst of interest to generate a current corresponding to the concentration of the analyte, the reagent being fixed in the groove of the fist insulating substrate; and

a second insulating substrate bonded into the first insulating substrate, the second insulating substrate forming a capillary space, along with the groove.

2. The electrochemical biosensor test strip as set forth in claim 1, wherein the electrodes are formed of a noble metal selected from the group consisting of gold, silver, platinum and palladium.

3. The electrochemical biosensor test stop as set forth in claim 1, wherein the electrodes are formed of a double layer structure comprising a lower layer of a metal and an upper layer of a noble metal select from the group consisting of gold, silver, platinum and palladium.

4. The electrochemical biosensor test strip as set forth in claim 1, wherein the first insulating substrate is formed of a polymer selected from the group consisting of polyethylene terephthalate, polyester, polycarbonate, polystyrene, polyimide, polyvinyl chloride, and polyethylene.

5. A biosensor system, comprising:

an electrochemical biosensor test stop of claim 1; and

a detector for displaying an analyte concentration in a sample, the detector being electrically connected with both the working electrode and the reference electrode, applying an electric potential across the two electrodes, and measuring the current generated as a result of the reaction between the reagent and the sample.

6. A method for fabricating an electrochemical biosensor test strip, comprising the steps of:

forming a groove in a first insulating substrate in a widthwise direction;

sputtering a metal material onto the first insulating substrate with the aid of a shadow mask to form a pair of electrodes parallel in a longwise direction across the groove on the first insulating substrate;

fixing a reagent within the groove of the first insulating substrate across a pair of the electrodes, the reagent reacting with an analyte of interest to generate a current corresponding to the concentration of the analyte; and

bonding a second insulating substrate onto the first insulating substrate, the second insulating substrate forming a capillary space, along with the groove in which the reagent is fixed.

7. The method as set forth in claim 6, wherein the electrodes are formed of a noble metal selected from the group consisting of gold, silver, platinum and palladium.

8. The method as set forth in claim 6, wherein the electrodes are formed of a double layer structure comprising a lower layer of a metal and an upper layer of a noble metal selected from the group consisting of gold, silver, platinum and palladium.

9. The method as set forth in claim 6, wherein the shadow mask is attached to the first insulating substrate by sue of a magnet.

10. The method as set forth in claim 6, wherein the shadow mask is formed of an aluminum alloy which is excellent in thermal transmission and magnetic properties.

11. The method as set forth in claim 6, wherein the shadow mask ranges, in thickness, from 0.1 to 0.3 mm.

12. The method as set forth in claim 6, wherein the sputtering step comprises:

applying an adhesive layer over the first insulating substrate to bond a mask film onto the first insulating substrate;

cutting the mask film and adhesive in a desired pattern;

removing the cut area from the mask film and adhesive and depositing a metal element over the resulting structure; and

removing the remaining mask film and adhesive.

13. The method as set forth in claim 6, wherein the fist insulating substrate is formed of a polymer selected from the group consisting of polyethylene terephthalate, polyester, polycarbonate, polystyrene, polyimide, polyvinyl chloride, and polyethylene.

14. The method as set forth in claim 6, further comprising the step for conducting an arc discharging or a plasma etching process over the first insulating substrate, prior to the sputtering step.

15. The method as set forth in claim 6, wherein the shadow mask has a three-dimensional structure suitable to fit to the groove of the first insulating substrate.

16. The method as set forth in claim 6, wherein the sputtering step is conducted using a collimater.