Diagnostic devices incorporating fluidics and methods of manufacture

• US 20040222091A1
• Filed: 06/01/2004
• Published: 11/11/2004
• Est. Priority Date: 12/02/2002
• Status: Active Grant

• Current Assignee: Siemens Healthcare Diagnostics Incorporated (Siemens AG)
• Original Assignee: Epocal Incorporated (Siemens AG)
• Inventors: MacZuszenko, Andrzel, Lauks, Imants
• Granted Patent: US 7,842,234 B2
• Time in Patent Office: Days
• US Class Current: 204/400
• CPC Class Codes: B01L 2200/025 Align devices or objects to ensure defined positions relative to each other
• CPC Class Codes: B01L 2200/0689 Sealing
• CPC Class Codes: B01L 2200/148 Specific details about calibrations
• CPC Class Codes: B01L 2200/16 Reagents, handling or storing thereof
• CPC Class Codes: B01L 2300/0645 Electrodes
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2300/0887 Laminated structure
• CPC Class Codes: B01L 2300/1805 Conductive heating, heat from thermostatted solids is conducted to receptacles, e.g. heating plates, blocks
• CPC Class Codes: B01L 2300/1827 using resistive heater
• CPC Class Codes: B01L 2400/0481 squeezing of channels or chambers
• CPC Class Codes: B01L 2400/0487 fluid pressure, pneumatics
• CPC Class Codes: B01L 2400/0683 mechanically breaking a wall or membrane within a channel or chamber
• 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: B01L 3/502715 characterised by interfacing components, e.g. fluidic, electrical, optical or mechanical interfaces
• CPC Class Codes: B01L 3/502723 characterised by venting arrangements
• CPC Class Codes: B01L 3/50273 characterised by the means or forces applied to move the fluids micropumps F04B19/006, of the membrane type F04B43/043
• CPC Class Codes: B01L 3/502738 characterised by integrated valves microvalves F16K99/0001
• CPC Class Codes: B01L 7/00 Heating or cooling apparatus autoclaves B01J3/04; Heat insulating devices
• CPC Class Codes: B32B 2038/047 Perforating
• CPC Class Codes: B32B 2425/00 Cards, e.g. identity cards, credit cards
• CPC Class Codes: B32B 37/06 : characterised by the heating method
• CPC Class Codes: B32B 37/10 : characterised by the pressing technique, e.g. using action of vacuum or fluid pressure
• CPC Class Codes: B32B 38/04 : Punching, slitting or perforating
• CPC Class Codes: G01N 2021/0193 : the sample being taken from a stream or flow to the measurement cell
• CPC Class Codes: G01N 2021/7756 : Sensor type
• CPC Class Codes: G01N 2035/00148 : Test cards, e.g. Biomerieux or McDonnel multiwell test cards
• CPC Class Codes: G01N 27/26 : by investigating electrochemical variables; by using electrolysis or electrophoresis
• 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 27/3274 : Corrective measures, e.g. error detection, compensation for temperature or hematocrit, calibration coding of calibration information G01N33/48771
• CPC Class Codes: G01N 27/403 : Cells and electrode assemblies

Abstract

The present invention relates to diagnostic devices incorporating electrode modules and fluidics for performing chemical analyses. The invented devices consist of a sensor array formed on an electrode module, the sensor array being contained within a fluidic housing. The electrode module is a laminate of a perforated epoxy foil and a photo-formed metal foil with sensor membranes deposited into the perforations. The fluidic housing is an element consisting of a plastic card-like body with fluidic conduits and a sealed fluid reservoir contained in a foil-lined cavity.

Claims

1. A diagnostic card for use with a card reader in sensing at least one component concentration of a fluid sample, comprising:

a card body

at least one component sensor located in a sensor region of the card body;

a sealed chamber defined in the card body outside the sensor region for containing a fluid;

a fluid conduit for fluidically connecting the chamber with the sensor region;

a valve located in the chamber for fluidically connecting the chamber to the fluid conduit; and

a delivery structure separate and distinct from the valve for forcing fluid from the chamber, when the chamber contains fluid, and into the fluid conduit.

2. The diagnostic card of claim 1, wherein the chamber is formed of a laminate of two opposed, plastic coated metal foil laminations bonded about their perimeter by a first heat seal made by melt bonding the plastic coatings of the laminations.

3. The diagnostic card of claim 2, wherein the heat seal has a width of at least 3 mm.

4. The diagnostic card of claim 1, wherein the chamber includes separate fill and vent openings for filling of the chamber with a fluid without pressurization.

5. The diagnostic card of claim 4, wherein the chamber is filled with fluid and the fill and vent openings are sealed to completely seal off the filled chamber.

6. The diagnostic card of claim 5, wherein the chamber is formed of a laminate of two opposed, plastic coated metal foil laminations bonded about their perimeter by a first heat seal made by melt bonding the plastic coatings of the laminations and the fill and vent openings are sealed by a second heat seal made by melt bonding the plastic coatings of the laminations about the fill and vent openings.

7. The card of claim 1, wherein the chamber is sealed by a chamber wall, the card body includes a valve seat and the valve includes a valve body displaceably received in the valve seat, the valve body and valve seat being shaped and constructed for rupturing a portion of the chamber wall upon displacement of the valve body relative to the valve seat.

8. The card of claim 2, wherein the valve includes a valve body displaceably received in a valve seat in the card body, the valve body being sandwiched between the laminations within the chamber, the valve body and valve seat being shaped and constructed for rupturing one of the laminations upon displacement of the valve body relative to the valve seat.

9. The card of claim 8, wherein the valve body is a rupture plug and the valve seat is a plug receiving bore in the card body.

10. The card of claim 9, wherein the plug and plug receiving bore include cooperating edges for rupturing the one of the laminations upon displacement of the plug in the plug receiving bore.

11. The card of claim 2, wherein the card body includes molded contours and one of the foil laminations is pressure-formed into the contours of the card body.

12. The card of claim 1, wherein the chamber has a chamber wall and a chamber volume and the delivery structure is formed by a flexible portion of the chamber wall which is deformable for reduction of the chamber volume.

13. The card of claim 1, wherein the chamber is made of a pair of opposed, plastic coated metal foil laminations defining the chamber wall and bonded about their perimeter by a first heat seal achieved by melt bonding the plastic coatings of the laminations about their perimeter, the card body further including a fill opening in communication with the chamber through one of the laminations for filling of the chamber with a fluid;

and a vent opening remote from the fill opening and in communication with the chamber through one of the laminations for venting of air in the chamber during filling of the chamber with the fluid, the fill and vent openings being sealable for complete sealing of the chamber by a second heat seal melt bonding the plastic coatings about the fill and vent openings.

14. An electrode module for use in a diagnostic card for sensing at least one component concentration in a fluid sample, comprising

a substantially planar insulator layer;

and

a substantially planar metal conductor layer laminated to the insulator layer;

the electrode module having a centrally located sensing region, a peripherally located contacting region and an intermediate heating region,

the insulator layer in the sensing region having a number of throughgoing apertures, a sensor membrane in each aperture for contact with the sample and for electrical contact with the conductor layer, the conductor layer being divided into a corresponding number of conductor elements and a heater contact element, each conductor element including a conductor path having a sensor end and an opposite contact pad end, the sensor ends being located in the sensing region of the module and below one of the apertures respectively and the contact pad ends being located in the contact region, the heater contact element being electrically insulated from the conductor elements and surrounding the sensing region in the heating region, the heater contact element having a connecting gap extending between the sensing and contact regions and the conductor paths extending through the connecting gap.

15. The electrode module as defined in claim 14, wherein the insulator layer is an epoxy resin foil and the conductor layer is a metal foil.

16. An electrode module as defined in claim 14, wherein the conductor paths are tortuously long to reduce thermal conduction along the conductor paths.

17. The electrode module as defined in claim 14, wherein the heater contact element includes a pair of connecting gaps located on opposite sides of the heating region and the conductor paths each extend through one of the connecting gaps.

18. The electrode module as defined in claim 14, wherein the heater contact element includes multiple connecting gaps corresponding in number to the conductor elements, each conductor path extending through one connecting gap.

19. The electrode module as defined in claim 18, wherein the connecting gaps and contact pad ends are positioned about the sensing region in such a way that all conductor paths are of equal length.

20. The electrode module as defined in claim 15, wherein the module has a rectangular shape and the contacting region extends along a pair of opposite sides of the electrode module, the module including eight apertures and eight conductor elements, the contact pad ends being symmetrically evenly distributed in the contacting region in two rows along the opposite sides and the sensor ends being symmetrically arranged in two parallel rows in the sensing region.

21. A diagnostic card for use with a card reader for sensing at least one component concentration of a fluid sample, comprising

a card body having a measurement cell for containing a sample fluid;

a passage for supplying the sample fluid to the measurement cell; and

an electrode module mounted to the card body and including a substantially planar insulator layer and a substantially planar metal conductor layer laminated to the insulator layer;

the electrode module having a centrally located sensing region, a peripherally located contacting region and an intermediate heating region,

the insulator layer in the sensing region having a number of throughgoing apertures, a sensor membrane in each aperture for contact with the sample fluid and for electrical contact with the conductor layer, the conductor layer being divided into a corresponding number of conductor elements and a heater contact element, each conductor element including a conductor path having a sensor end and an opposite contact pad end, the sensor ends being located in the sensing region of the module and below one of the apertures respectively and the contact pad ends being located in the contact region, the heater element being located in the heating region and electrically insulated from the conductor elements and surrounding the sensor region, the heater element having a connecting gap extending between the sensor and contact regions and the conductor paths extending through the connecting gap;

the electrode module being mounted to the card body for exposure of the sensor membranes to the measurement cell and for external access to the contact pad ends and the heater contact element.

22. The diagnostic card as defined in claim 21, wherein the insulator layer is an epoxy resin foil and the conductor layer is a metal foil.

23. The diagnostic card as defined in claim 21, wherein the insulator layer is adhesively bonded to the card body about the sensing region for preventing leakage of any fluid contained in the measurement cell about an edge of the electrode module to the conductor layer.

24. The diagnostic card as defined in claim 21, wherein the conductor paths are tortuously long to reduce thermal conduction along the conductor paths.

25. The diagnostic card as defined in claim- 21, wherein the heater element includes a pair of connecting gaps located on opposite sides of the heating region and the conductor paths respectively extend through one of the connecting gaps.

26. The diagnostic card as defined in claim 21, wherein the module has a rectangular shape and the contacting region extends along a pair of opposite sides of the electrode module, the module including eight apertures and eight conductor elements, the contact pad ends being symmetrically evenly distributed in the contacting region along the opposite sides of the electrode module and the sensor ends being symmetrically arranged in two parallel rows in the sensing region.

27. The diagnostic card of claim 21, further including a passage for draining excess fluid away from the measurement cell.

28. A diagnostic card reader for use with a diagnostic card having substantially planar opposite first and second surfaces, a measuring region and an electrode module located in the measuring region and having a conductor layer exposed in the first surface, the conductor layer being divided into a substantially central sensing region, a substantially peripheral contacting region including electrode contact ends, and an intermediate heating region surrounding the sensing region and including a heater contact element, the card reader comprising:

a housing;

a card cavity for receiving at least a portion of the diagnostic card to locate the conductor layer of the electrode module inside the card cavity;

a contacting arrangement for electrically contacting at least one of the electrode contact ends of the electrode module when the card is received in the card cavity; and

a first heater block for heating the sensing region of the electrode module when the card is received in the card cavity, the heater block having a first block portion for physically contacting the heater contact element of the electrode module and heating the heating region by direct thermal conduction, and a second block portion backset from the first portion to be spaced apart parallel to the sensing region of the electrode module when the first block portion is in physical contact with the heater contact element for heating the sensing region by indirect thermal transfer.

29. The card reader of claim 28, wherein the contacting arrangement includes at least one metal contacting element in the form of a formed metal film carried on a flex substrate mounted on a flexible support in the card reader'"'"'s card insertion orifice for resiliently contacting the contact end when the card is received in the card cavity.

30. The card reader as defined in claim 28, further comprising a second heater block for physically contacting the second surface of the card in the measuring region for heating at least the portion of the measuring region which coincides with the sensing region of the card and for heating any liquid within the card in the measuring region.

31. The card reader as defined in claim 30, wherein the heater block extends beyond the measuring region for heating fluid in any conduits in the card leading to and from the measuring region.

32. A diagnostic card for use with a card reader for sensing at least one component concentration of a fluid sample, comprising:

a planar card body having a pair of opposite planar surfaces;

at least one sensor located in a sensor region of the card body;

a sample entry port on one of the surfaces of the card;

a sample conduit within the card body for fluidically connecting the sample entry port to the sensor region; and

an adhesive gasket surrounding the sample entry port for forming a liquid seal about a conduits inserted into the sample entry port for sample fluid injection.

33. A method of forming a sealed fluid reservoir in a diagnostic card, comprising the steps of obtaining a diagnostic card body with a reservoir recess in a surface of the card body;

lining the recess with a first laminate of a plastic film layer and an aluminum foil layer, the foil layer contacting the card body and the first laminate extending beyond the recess;

placing a second laminate of a plastic film layer and an aluminum foil layer over the first laminate so that the plastic film layers contact one another; and

forming a sealed reservoir by heat bonding the film layers along a periphery of the first and second laminates forming a continuous heat bond line.

34. The method of claim 33, wherein the first laminate is pressure formed into the recess to closely follow a contour of the recess.

35. The method of claim 33, wherein the heat bond line has a minimum transverse width of 3 mm.

36. The method of claim 33, wherein the recess includes a filler passage and a vent passage and the method includes the additional steps of perforating the first laminate over the filler and vent passages to form filler and vent openings therein, filling the sealed reservoir after heat bonding of the film layers by injecting fluid through the filler opening, and sealing the reservoir by forming a second heat bond of the film layers about the filler and vent openings.

37. The method of claim 34, comprising the further step of, prior to placement of the second laminate, placing a rupture plug on the first laminate at a desired location of rupture so that the rupture plug is contained in the reservoir after heat bonding of the film layers.

38. The method of claim 37, wherein the card body includes a plug receiving bore, the first laminate is pressure formed into the recess to closely follow a contour of the recess and the plug receiving bore, the plug is shaped and sized to slidably fit into the plug receiving bore, and the plug is placed at the location of the plug receiving bore prior to placement of the second laminate.