Measuring device and measuring method for detecting analytes

• US 20060076249A1
• Filed: 09/07/2005
• Published: 04/13/2006
• Est. Priority Date: 09/09/2004
• Status: Active Grant

• Current Assignee: Analyticon Biotechnologies AG (77 Elektronika Muszeripari Kft.)
• Original Assignee: Analyticon Biotechnologies AG (77 Elektronika Muszeripari Kft.)
• Inventors: Meisegeier, Bernhard, Zwingmann, Detlev, Schaper, Reinhard, Oberstrass, Jurgen
• Granted Patent: US 7,658,825 B2
• Time in Patent Office: Days
• US Class Current: 205/792
• CPC Class Codes: C12Q 1/002 Electrode membranes
• CPC Class Codes: G01N 33/5438 Electrodes

Abstract

A measuring device for the detection and determination of the concentration of at least one analyte in a liquid medium consists of a polymeric carrier having biologically active specific binding molecules dried on its upstream portion. A multiple electrode set consisting of at least one reference electrode and at least one working electrode is located thereon in a downstream region. The working electrode is provided with biologically active specific binding molecules. The carrier has a sample application zone, which is adjoined, in the downstream direction, by a non-deformable, through-flow reaction and detection chamber, a variably dimensioned interstice, and a liquid absorption element. For a qualitative and quantitative analyte determination, two liquid media are applied in succession to the sample application zone. While the first can contain the wanted analyte, the second provides for the formation of an electrical signal.

Claims

1. A device for the detection and/or determination of the concentration of at least one analyte present in a liquid medium, consisting of

a) a strip-shaped carrier (20) having two longitudinal edges (24), to which carrier (20) a printed multiple electrode set consisting of at least one reference electrode (30) and at least one working electrode (40) is applied and

b) ligands which are suitable for binding a biologically active specific binding molecule or the analyte,

wherein the device

a) comprises a rigid reaction and detection chamber (50) adapted for continous flow of the medium along said strip-shaped carrier (20), said reaction and detection chamber being formed by an elongated support (52) applied to said longitudinal edges (24) of said carrier (20) having a cover (54) disposed on said support (52) and that

b) a liquid absorption element (60) is disposed downstream of said reaction and detection chamber (50).

2. The device as claimed in claim 1, wherein said carrier (20) is designed as a self-supporting flow surface for the liquid medium.

3. The device as claimed in claim 1, wherein said carrier (20) is unitary and consists of a polymeric, nonconducting, preferably rectangular material.

4. The device as claimed in claim 1, wherein said ligands and/or biologically active specific binding molecules are applied to said carrier (20).

5. The device as claimed in claim 4, wherein said ligands and/or said biologically active specific binding molecules are immobilized on said carrier (20).

6. The device as claimed in claim 1, wherein said carrier (20) is provided with a base coating which consists of proteins selected from the group consisting of the animal or human albumins and/or from the group consisting of the globulins and/or from the group consisting of the glycoproteins.

7. The device as claimed in claim 1, wherein said carrier (20) is provided with a base coating which consists of polypeptides, for example polyamino acids and/or degradation products of proteins, preferably of the supportive and connective tissue.

8. The device as claimed in claim 1, wherein a sample application zone (22) is formed on one end of said carrier (20).

9. The device as claimed in claim 8, wherein said sample application zone (22), or at least a part thereof, is treated with surface-active substances and possesses the ability to absorb the liquid medium.

10. The device as claimed in claim 8, wherein a mesh-like or porous material, preferably treated with surface-active substances, is provided on said sample application zone (22).

11. The device as claimed in claim 1, wherein each working electrode (40) and each reference electrode (30) is connected conductively to a conductive track (42) assigned thereto, and each conductive track (42) is conductively connected to an assigned contact (44) which is connectable to an electrical measuring apparatus.

12. The device as claimed in claim 11, wherein at least one of said electrodes (30, 40) and its assigned conductive track (42) and its assigned contact (44) consists of gold, silver, platinum, nickel, palladium, titanium, copper, or carbon.

13. The device as claimed in claim 1, wherein at least one of said electrodes (30, 40) consists of a dried graphite paste or is an electrode to be prepared from metal pastes and/or metal salt pastes by drying.

14. The device as claimed in claim 1, wherein at least one of said working electrodes (40) carries ligands and/or biologically active specific binding molecules, for example on its surface.

15. The device as claimed in claim 1, wherein reaction-nonspecific binding molecules are disposed and/or immobilized on at least one further working electrode (40).

16. The device as claimed in claim 1, wherein said ligands are applied as a solution having a concentration of 0.0007 to 0.7 mol/l, preferably of 0.035 to 0.35 mol/l.

17. The device as claimed in claim 1, wherein said ligands are formed from ribonucleic acids or deoxyribonucleic acids.

18. The device as claimed in claim 1, wherein said ligands consist of aminocarboxylic acids, preferably diaminocarboxylic acids.

19. The device as claimed in claim 18, wherein said ligands consist of non-monomeric homodet or heterodet aminocarboxylic acids of the composition R—

CH(NH₂)—

(CH₂)_n—

COOH linked in peptide-like form, for example of polyaminocarboxylic acids, where R stands for a proton or preferably for an amino, imino, hydroxyl, thiol, hydroxyalkyl, aminoalkyl or carboxyalkyl group and n assumes a value of from 0 to 6, preferably 0.

20. The device as claimed in claim 1, wherein said ligands consist of proteides or of proteins which preferably originate from the bacterium Streptomyces avidinii.

21. The device as claimed in claim 1, wherein for example for the detection of HbA1c, at least one ligand is a phenylboronic acid.

22. The device as claimed in claim 1, wherein said biologically active specific binding molecules possess binding sites for at least one ligand or are bound thereto.

23. The device as claimed in claim 1, wherein said biologically active specific binding molecules have at least one specific binding region for binding an analyte.

24. The device as claimed in claim 1, wherein a catalytically active protein is preferably covalently bonded to said biologically active specific binding molecules and/or said ligands or a number of catalytically active proteins are preferably covalently bonded to said biologically active specific binding molecules and/or said ligands.

25. The device as claimed in claim 1, wherein the elongated support (52) is divided in two and is permanently adhesively attached, in the form of two strips, to the two longitudinal edges (24) of said carrier (20).

26. The device as claimed in claim 25, wherein said strips consist of a polymer material and/or of a melt adhesive and possess the same thickness as said liquid absorption element (60).

27. The device as claimed in claim 25, wherein said strips only lie on one part of said two longitudinal edges (24) of said carrier (20), there being an interstice (70) between said strips and said liquid absorption element (60), from which interstice (70) said strips extend upstream on said longitudinal edges (24).

28. The device as claimed in claim 1, wherein said cover (54) consists of a polymeric, preferably rectangular, material and is connected to said elongated support (52) in such a way that it covers said carrier (20) and also said multiple electrode set and said liquid absorption element (60).

29. The device as claimed in claim 1, wherein said cover (54) only covers one or more parts of said carrier (20).

30. The device as claimed in claim 8, wherein said cover (54) possesses on its upstream side at least one slot-shaped and/or semicircular or polygonal recess (56) and/or opening (56), which is arranged in such a way that said sample application zone (22) of said carrier (20) can be charged with liquid medium.

31. The device as claimed in claim 1, wherein said liquid absorption element (60) is adhesively fixed to that side of said cover (54) which faces said carrier (20).

32. The device as claimed claim 1, wherein said cover (54) or at least a part thereof is treated with surface-active substances.

33. The device as claimed in claim 8, wherein the side of said cover (54) facing said carrier (20) in the region of said multiple electrode set, in particular above said working electrode(s) (40) and above said reference electrode (30) possesses hydrophilic properties and has, at least in part, a hydrophobic surface in the region of said sample application zone (22).

34. The device as claimed in claim 27, wherein said reaction and detection chamber (50) is open in the downstream and upstream directions and said interstice (70) borders on its downstream end.

35. The device as claimed in claim 11, wherein said liquid absorption element (60) is disposed on said carrier (20) at a downstream distance from said sample application zone (22) and covers said conductive tracks (42), for example rests directly thereon.

36. The device as claimed claim 1, wherein said liquid absorption element (60) consists of an absorbent porous fibrillar material and is fixed adhesively to said carrier (20).

37. The device as claimed in claim 36, wherein said porous material is constructed from at least one fiber layer or at least one fabric, which consists of cellulose fibers or glass fibers or mixtures thereof or is composed of organic polymers.

38. The device as claimed in claim 1, wherein said liquid absorption element (60) is treated with surface-active substances, preferably with those having hydrophilic properties.

39. The device as claimed in claim 9, wherein said surface-active substances contain hydrophilic groups, for example —

COOMe, —

OSO₃Me, —

SO₃Me, —

NH₂, ═

NH, —

NR₃⁺ and hydrophobic alkyl chains having from 10 to 18 carbons or alkylaryl groups.

40. The device as claimed in claim 9, wherein the surface-active substances used are preferably substances having the empirical formulae C₂₀H₃₇NaO₇S or C₁₈H₂₉NO₃S.

41. The device as claimed in claim 3, wherein said polymeric material is a polyethylene, a polystyrene, a polyurethane, a polyvinyl acetate, a polyester, for example polyethylene terephthalate, an epoxy resin, a methacrylic polymer, a polycarbonate, a polyvinyl chloride, or a copolymer of said compounds.

42. The device as claimed in claim 3, wherein said polymeric material is a foil, preferably manufactured from polyester, polycarbonate, or polyvinyl chloride.

54. In a method of detecting and determining the concentration of at least one analyte in body fluids such as whole blood, plasma, serum, urine, secretion, cerebrospinal fluid, and from extracts of body tissues, and from swab material, the improvement comprising using the device of claim 1.

43. A method for the production of a device (10) for the detection and determination of the concentration of at least one analyte dissolved in a liquid medium, wherein

a) an electrode material is worked to a paste and this paste is applied to a carrier (20) in such a way that a multiple electrode set consisting of at least one working electrode (40) and at least one reference electrode (30) and adjoining conductive tracks (42) and contacts (44) is formed,

b) said carrier (20) provided with said multiple electrode set is dried at elevated temperature,

c) ligands and/or biologically active specific binding molecules and/or catalytically active proteins are applied to said carrier (20), namely in said region of said multiple electrode set or in a region which is disposed upstream of said multiple electrode set and

d) an elongated support (52), a cover (54), and a liquid absorption element (60) are fixed to the carrier (20) thus obtained such that said cover (54) and said carrier (20) are spaced from one another.

44. The method as claimed in claim 43, wherein said paste contains ligands and/or biologically active specific binding molecules and/or catalytically active proteins and is applied by means of a screen printing technique.

45. The method as claimed in claim 43, wherein at least one of said dried electrodes (40) is coated with ligands and/or biologically active, specific binding molecules and/or catalytically active proteins, preferably with the aid of crosslinking molecules or coupling reagents.

46. The method as claimed in claim 43, wherein at least one of said dried electrodes (40) is coated with ligands and/or reaction-nonspecific binding molecules, preferably with the aid of crosslinking molecules or coupling reagents.

47. The method as claimed in claim 43, wherein liquid absorption element (60) is treated with a solution of a surface-active substance and dried, this substance, in a preferred embodiment, being a compound of the empirical formula C₂₀H₃₇NaO₇S or C₁₈H₂₉NO₃S, which is used in a concentration of from 0.001 to 5% w/v, preferably from 0.1 to 3% w/v.

48. A method for the detection and determination of the concentration of at least one analyte dissolved in a liquid medium using a device (10) which consists of at least one working electrode (40) and at least one reference electrode (30, wherein

a) a definable amount of said liquid medium is applied to a sample application zone (22) of said device (10),

b) a specified period of time is allowed to elapse in order to allow interaction of said analyte(s) with ligands and/or biologically active specific binding molecules and/or catalytically active proteins to take place,

c) a solution is applied to the sample application zone (22), which contains at least one reaction-specific substrate for a catalytically active protein or a number of catalytically active proteins,

d) said device (10) is connected to an electrical measuring apparatus, and

e) after an incubation time, an electrical signal is read off on said measuring apparatus connected to said device (10) for each analyte to be determined and a corresponding concentration of the respective analyte is assigned to this signal with the aid of a calibration curve.

49. The method as claimed in claim 48, wherein said definable amount is from 0.01 to 20 μ

l, preferably from 1 to 10 μ

l, and said specifiable period of time is between 5 and 600 seconds, preferably between 10 and 120 seconds and more preferably between 20 and 60 seconds.

50. The method as claimed in claim 48, wherein an amount of said solution containing reaction-specific substrate of between 0.1 μ

l and 500 μ

l, preferably between 1 μ

l and 100 μ

l and more preferably between 10 μ

l to 30 μ

l, is applied by pipette.

51. The method as claimed claim 48, wherein the incubation time is in a range of from 2 to 100 seconds, preferably from 5 to 30 seconds, and is more preferably 20 seconds.

52. The method as claimed in claim 48, wherein said electrical signal read off is compared with another electrical signal which originates from a second, nonspecific working electrode (40″

), this second working electrode (40″

) being provided with only reaction-nonspecific ligands or binding molecules.

53. (canceled)