New spacer forming method used for a biosensor

• US 20030046811A1
• Filed: 09/10/2001
• Published: 03/13/2003
• Est. Priority Date: 09/10/2001
• Status: Active Grant

• Current Assignee: Eumed Biotechnology Co., Ltd.
• Original Assignee: Eumed Biotechnology Co., Ltd.
• Inventors: Chang, Ching-Yu, Lee, Cherng-Jyh, Chen, Tzer-Ming
• Granted Patent: US 6,787,013 B2
• Time in Patent Office: Days
• US Class Current: 29/832
• CPC Class Codes: A61B 2562/0295 Strip shaped analyte sensors for apparatus classified in A61B5/145 or A61B5/157 disposable multilayered or laminated electrodes G01N27/307; details of handling chemical test elements G01N33/4875
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: C12Q 1/001 Enzyme electrodes
• CPC Class Codes: G01N 33/5438 Electrodes
• CPC Class Codes: Y10T 29/49105 Switch making
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing
• CPC Class Codes: Y10T 29/49126 Assembling bases
• CPC Class Codes: Y10T 29/4913 Assembling to base an electrical component, e.g., capacitor, etc.
• CPC Class Codes: Y10T 29/49155 Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/49156 with selective destruction of conductive paths

Abstract

A spacer forming method for a biosensor that has a biosensor possessing a capillary sampling channel and electrical connecting tracks for the use of a specific portable meter. A pair of electrodes is printed on an insulating base plate to be the transducer of the electrochemical biosensor by means of the screen-printing technology. The advanced thick-film printing technology is employed to construct the spacer component of the sampling channel that precisely controls the volume of a sample solution. Therefore, the spacer forming method reduces the usage of adhesive that otherwise causes a serious problem during a continuous punching procedure. Furthermore, the embedded switch pad on the biosensor is introduced to be instead of a micro switch in a connector of the portable meter.

Claims

1. A spacer forming method for a biosensor, the spacer forming method comprising the acts of:

printing the conductive matter on a substrate (1) to form a conducting layer by means of the screen printing or stainless stencil printing technology and drying the conductive matter as the requirements of the selected paste;

completely overlapping the conducting layer with an electrode layer by means of screen-printing or stainless stencil printing technology and drying the electrode layer as the requirements of the selected paste;

constructing an insulating layer (6) on the electrode layer by the screen-printing or stainless stencil printing technology and curing the insulating layer as the requirements of the selected paste;

disposing a spacer layer (9) on the insulating layer (6) by a stainless stencil printing technology, and curing the spacer layer as the requirements of the selected paste ; and

adhering a protecting layer with one side precoated partially with hydrophilic polymer to form the spacer layer (9) to reserve an inlet port (15) and an outlet port (16), and keeping the coated side to a sampling channel (13).

2. A biosensor produced by the acts in accordance with the spacer forming method in claim 1, wherein the biosensor comprising:

a substrate (1) formed as a base of the biosensor;

an anode conducting track (2) and a cathode conducting track (2′

) mounted on the substrate (1) to be a working electrode conducting track and a counter electrode conducting track respectively;

a pair of electrode tracks (4,4′

) disposed on the corresponding conducting track (2,2′

) to provide a suitable surface for electrochemical measurement of the biosensor;

a switch comprising a switch pad (5) and a conducting pad (3), wherein the switch pad (5) is constructed on a conducting pad (3), and the switch controls actuation of the electrical system when the biosensor is inserted in a connector of a meter;

an insulating layer (6) disposed on the electrode tracks (4,4′

) and the switch pad (5), and having an opening defined therein to construct a reaction area (7) and a connecting area (14);

a spacer layer (9) disposed on the insulating layer (6) and having a sample ditch (10) defined in the spacer layer (9) to correspond to the reaction area (7) and construct walls of the reaction area (7) to guide the sample solution flow;

a reagent layer (8) disposed on the reaction area (7) and re-dissolved rapidly when the reagent layer (8) contacts with the sample solution;

a protecting layer (11) having a hydrophilic membrane adhered on one face directed toward to the biosensor and transversely mounted on the sample ditch (10) of the spacer layer (9) to form an inlet port (15) and an outlet port (16) so that a sampling channel (13) is constructed inside the biosensor.

3. The biosensor as claimed in claim 2, wherein the substrate (10) is made of polymer materials selected from the following group comprising:

polyvinyl chloride (PVC), polyethylene terephthalate (PET), polycarbonate (PC), polypropylene (PP), polyethylene (PE), polybutylene terephthalate (PBT), polystyrene (PVDF), polyamide (PA), bakelite, fiberglass, glass, and ceramics.

4. The biosensor as claimed in claim 2, wherein the conducting tracks (2,2′

) and the conducting pad (3) are made of conductive materials selected from the following group comprising;

carbon paste, silver paste, silver chloride paste, gold paste, palladium paste, gold, platinum, and palladium.

5. The biosensor as claimed in claim 2, wherein the electrode tracks (4,4′

) and the switch pad (5) are made of materials selected from the following group;

carbon paste, gold paste, palladium paste, gold, platinum, and palladium.

6. The biosensor as claimed in claim 2, wherein the insulating layer (6) is made of materials selected from the following group:

acrylic resin, epoxy resin, polyurethane resin, silicon resin, phenol resin, alkyd resin, maleic alkyd resin, urea resin, and polyester resin.

7. The biosensor as claimed in claim 2, wherein the insulating spacer layer (9) is made of materials selected from the following group:

acrylic resin, epoxy resin, polyurethane resin, silicon resin, phenol resin, alkyd resin, maleic alkyd resin, urea resin, and polyester resin.

8. The biosensor as claimed in claim 2, wherein the reagent layer (8) is composed of an enzyme, a buffer solution, a carrier, an electrical mediator, and a surfactant.

9. The biosensor as claimed in claim 8, wherein the reagent layer (8) has a preferred composition comprising:

Glucose oxidase, PVA, Potassium ferricyanide, Phosphate buffer, and Triton X- 100.

10. The biosensor as claimed in claim 2, wherein material of the protecting layer is selected from polyvinyl chloride (PVC), polyethylene terephthalate (PET) and polypropylene (PP).

11. The biosensor as claimed in claim 2, wherein material of the hydrophilic membrane is selected from at least one of the following group:

Triton X- 100, polyoxymethylene sorbitan, starch, carboxymethyl cellulose, gelatin, acrylate, polyethylene glycol, polyvinyl alcohol, and polyvinylpyrrolidone.

12. The spacer forming method for a biosensor as claimed in claim 1, wherein the conducting layer is disposed on the substrate (1) by means of screen printing, stainless stencil printing, physical vapor deposition (PVD), chemical deposition (CVD), physical enhanced chemical vapor deposition (PECVD), and sputtering methods.

13. The spacer forming method for a biosensor as claimed in claim 1, wherein the electrode layer is disposed on the conducting layer by means of screen printing, stainless stencil printing, physical vapor deposition (PVD), chemical deposition (CVD), physical enhanced chemical vapor deposition (PECVD), and sputtering methods.

14. The spacer forming method for a biosensor as claimed in claim 2, wherein the switch is mounted on the connecting area (14).