Method of forming an electrochemical sensor

• US 8,298,487 B2
• Filed: 01/18/2007
• Issued: 10/30/2012
• Est. Priority Date: 12/12/2000
• Status: Active Grant

• Current Assignee: Ascensia Diabetes Care Holdings AG (PHC Holdings Corporation)
• Original Assignee: Bayer Healthcare LLC (Bayer AG)
• Inventors: Brenneman, Allen J., Wogoman, Frank W.
• Primary Examiner(s): Bullock, In Suk
• Assistant Examiner(s): HYUN, PAUL SANG HWA
• Application Number:
  US11/654,954
• Publication Number:
  US 20070116603A1
• Time in Patent Office: 2,112 Days
• Field of Search: 264/271, 264/271.1, 264/279.1, 264/328.1, 264/63, 264/272.11, 264/239, 264/299, 422/82.01, 422/82.02
• US Class Current: 422/82.02
• CPC Class Codes: B01L 2200/12 Specific details about manufacturing devices
• CPC Class Codes: B01L 2300/0645 Electrodes
• CPC Class Codes: B01L 2300/0809 rectangular shaped
• CPC Class Codes: B01L 2300/0825 Test strips
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 3/5027 by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip B01L3/5023 takes precedence; micromixers B01F33/30; microreactors for synthesis B01J19/0093; microcapillary devices in general B81B1/00
• CPC Class Codes: B01L 3/502707 characterised by the manufacture of the container or its components by shaping or joining plastic parts B29C59/00, B29C65/00; by laminating B32B37/00; manufacture of microstructural devices in general B81C
• CPC Class Codes: B29C 2045/1477 Removable inserts, e.g. the insert being peeled off after moulding
• CPC Class Codes: B29C 45/14 incorporating preformed parts or layers, e.g. injection moulding around inserts or for coating articles B29C45/1671 takes precedence
• CPC Class Codes: B29C 45/14065 Positioning or centering articles in the mould
• CPC Class Codes: B29C 45/14639 for obtaining an insulating effect, e.g. for electrical components
• CPC Class Codes: B29C 45/14754 being in movable or releasable engagement with the coating, e.g. bearing assemblies
• CPC Class Codes: G01N 2021/0346 Capillary cells; Microcells
• CPC Class Codes: G01N 21/03 Cuvette constructions
• CPC Class Codes: G01N 27/4473 by electric means

Abstract

An electrochemical sensor with a capillary channel is formed by placing a sacrificial insert and electrodes on a sensor base and applying plastic material. After the plastic material is cured, the sacrificial is removed leaving a capillary channel in the sensor. The inserts may be removed by a tool including a clamp for clamping and holding each insert stationary and a sliding block to which the sensor is secured.

Claims

1. A method of molding an electrochemical sensor, the method comprising the acts of:

providing a first mold;

inserting a first electrical contact in the first mold;

inserting a second electrical contact in the first mold;

placing a sacrificial insert in the first mold;

closing the first mold with a second mold;

injecting material for forming the electrochemical sensor into the closed first and second molds;

curing the material;

opening the first and second molds with respect to each other; and

extracting the sacrificial insert from the cured material so as to leave a channel in the cured material and form the electrochemical sensor, the channel extending from a first end of the electrochemical sensor and terminating before a second end of the electrochemical sensor.

2. The method of claim 1 wherein the sacrificial insert comprises metal.

3. The method of claim 2 wherein the metal comprises stainless steel.

4. The method of claim 1 wherein the sacrificial insert comprises a material having a melt temperature higher than the melt temperature of the injected material.

5. The method of claim 1 further including disposing a reagent within the channel.

6. The method of claim 1 wherein the electrochemical sensor is adapted to analyze a liquid sample.

7. The method of claim 1 wherein the first mold includes a plurality of locator pins to assist in locating the first and second electrical contacts.

15. The method of claim 1, wherein the first end of the electrochemical sensor has a curved surface.

8. A method of forming an electrochemical sensor, the method comprising the acts of:

providing a sensor base;

placing a sacrificial insert on the sensor base;

placing a first electrical contact and a second electrical contact on the sensor base, the sacrificial insert being positioned between the first electrical contact and the second electrical contact;

placing plastic material on the sensor base and over the sacrificial insert; and

removing the sacrificial insert from the plastic material and the sensor base leaving a capillary channel in the plastic material so as to form the electrochemical sensor, the capillary channel extending from a first end of the electrochemical sensor and terminating before a second end of the electrochemical sensor.

9. The method of claim 8 wherein the sacrificial insert comprises metal.

10. The method of claim 9 wherein the metal comprises stainless steel.

11. The method of claim 8 wherein the sacrificial insert comprises a material having a melt temperature higher than the melt temperature of the plastic material.

12. The method of claim 8 further including disposing a reagent within the capillary channel.

13. The method of claim 8 wherein the electrochemical sensor is adapted to analyze a liquid sample.

16. The method of claim 8, wherein the first end of the electrochemical sensor has a curved surface.

14. A method of forming an electrochemical sensor, the method comprising the acts of:

providing a sensor base;

placing a sacrificial insert on the sensor base;

placing a first electrical contact and a second electrical contact in the sensor base, the sacrificial insert being positioned between the first electrical contact and the second electrical contact;

placing plastic material on the sensor base and over the sacrificial insert; and

removing the sacrificial insert from the plastic material and the sensor base leaving a capillary channel in the plastic material so as to form the electrochemical sensor, the capillary channel extending from a first end of the electrochemical sensor and terminating before a second end of the electrochemical sensor.

17. The method of claim 14, wherein the first end of the electrochemical sensor has a curved surface.