SENSOR UNIT, MEASURING METHOD AND PRODUCTION METHOD

Abstract

In a sensor unit, a sensor element having an optical behavior that depends on at least one analyte is in diffusive contact with an auxiliary medium, which is present in a reservoir in the sensor unit, via a membrane. The reservoir and the membrane, on the one hand, and sensor element, on the other hand, can be removed from one another in order to place the sensor unit in a measurement state. The auxiliary medium can serve to wet the sensor element during storage of the sensor unit or also for calibrating the sensor element.

Claims

1. A sensor unit comprising: a sensor element comprising an optical behavior, wherein the optical behavior depends on at least one analyte of a sample; a reservoir with an auxiliary medium; and a membrane wherein, in a preparation state of the sensor unit, the membrane enables a diffusive contact between the auxiliary medium and the sensor element, wherein the sensor unit is placed in a measurement state by removal from one another of the sensor element on the one hand and of the membrane and of the reservoir on the other hand.

2. The sensor unit according to claim 1, wherein the reservoir and the membrane are detachably connected to the sensor unit.

3. The sensor unit according to claim 2, further comprising a cap, wherein the cap is configured to cover the reservoir and the sensor element.

4. The sensor unit according to claim 3, wherein the sensor element is arranged on a support, the cap is detachably connected to the support, and the membrane is fastened in the cap.

5. The sensor unit according to claim 1, wherein the sensor unit further comprises: a sensor part, wherein the sensor element is attached to the sensor part; a reservoir part, wherein the reservoir is formed and the membrane is attached; and wherein the reservoir part and the sensor part are rotatable or displaceable with respect to one another.

6. The sensor unit according to claim 5, wherein the sensor part comprises a channel for guiding an optical waveguide.

7. The sensor unit according to claim 5, wherein the reservoir part comprises an opening through which the sensor element in the measurement state of the sensor unit is accessible from an environment of the sensor unit.

8. The sensor unit according to claim 1, wherein the auxiliary medium in the reservoir is configured as a storage medium for storing the sensor element in a wetted state in the sensor unit.

9. The sensor unit according to claim 8, wherein the storage medium comprises water or a lye.

10. The sensor unit according to claim 8, wherein the storage medium comprises an antimicrobial preservative.

11. The sensor unit according to claim 8, wherein the storage medium sets a defined state for calibrating the sensor element.

12. A sample vessel comprising: a sensor unit positioned in the sample vessel, wherein the sensor unit comprises: a sensor element comprising an optical behavior, wherein the optical behavior depends on at least one analyte of a sample; a reservoir with an auxiliary medium; and a membrane, wherein, in a preparation state of the sensor unit, the membrane enables a diffusive contact between the auxiliary medium and the sensor element, wherein the sensor unit is placed in a measurement state by removal from one another of the sensor element on the one hand and of the membrane and of the reservoir on the other hand.

13. The sample vessel of claim 12, wherein the reservoir and the membrane are detachably connected to the sensor unit.

14. The sample vessel of claim 13, further comprising a cap, wherein the cap is configured to cover the reservoir and the sensor element.

15. The sample vessel of claim 14, wherein the sensor element is arranged on a support, the cap is detachably connected to the support, and the membrane is fastened in the cap.

16. The sample vessel of claim 12, wherein the sensor unit further comprises: a sensor part, wherein the sensor element is attached to the sensor part; a reservoir part, wherein the reservoir is formed and the membrane is attached; and wherein the reservoir part and the sensor part are rotatable or displaceable with respect to one another.

17. The sample vessel of claim 16, wherein the sensor part comprises a channel for guiding an optical waveguide.

18. The sample vessel of claim 16, wherein the reservoir part comprises an opening through which the sensor element in the measurement state of the sensor unit is accessible from an environment of the sensor unit.

19. The sample vessel of claim 12, wherein the auxiliary medium in the reservoir is configured as a storage medium for storing the sensor element in a wetted state in the sensor unit.

20. The sample vessel of claim 19, wherein the storage medium comprises water or a lye.

21. The sample vessel of claim 19, wherein the storage medium comprises an antimicrobial preservative.

22. The sample vessel of claim 19, wherein the storage medium sets a defined state for calibrating the sensor element.

23. The sample vessel of claim 12, wherein the sample vessel is sterilized.

24. A method of measuring an analyte in a sample, the method comprising: providing a sample vessel with a sensor unit, wherein the sensor unit comprises: a sensor element comprising an optical behavior, wherein the optical behavior depends on at least one analyte of a sample; a reservoir with an auxiliary medium; and a membrane, wherein, in a preparation state of the sensor unit, the membrane enables a diffusive contact between the auxiliary medium and the sensor element, wherein the sensor unit is placed in a measurement state by removal from one another of the sensor element on the one hand and of the membrane and of the reservoir on the other hand; sterilizing the sample vessel; removing the sensor element, on the one hand, and the reservoir and the membrane, on the other hand, from one another in order to make the sensor element accessible from the sample vessel; filling the sample vessel with the sample; and performing a measurement of the analyte using the sensor element of the sensor unit.

25. A method for manufacturing a sensor unit, the method comprising: creating a cavity in a precut foil; attaching a sensor element to a transparent support, wherein the sensor element comprises an analyte dependent optical behavior; filling the cavity with an auxiliary medium; laying a membrane on the filled cavity and fastening the membrane to the foil, wherein the membrane is diffusive for the auxiliary medium; placing the support with the sensor element on the membrane, wherein the sensor element is configured toward the membrane in order to come into contact with the auxiliary medium diffused through the membrane; and fixing the support on the foil such that the foil together with the membrane and the cavity with the auxiliary medium can be removed from the support with the sensor element.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The present disclosure is explained in more detail below with reference to the attached schematic figures. The figures therefore are not intended to be construed as limitations of the invention to these specific embodiments.

[0048] FIG. 1 shows an embodiment of a sensor unit according one embodiment in sectional view.

[0049] FIG. 2 shows the embodiment of the sensor unit of FIG. 1 in plan view.

[0050] FIG. 3 shows a further embodiment of a sensor unit in sectional view in the preparation state.

[0051] FIG. 4 shows the embodiment from FIG. 3 in a sectional view in the measurement state.

[0052] FIGS. 5A-C illustrate the preparation for a measurement using a sensor unit illustrated in FIGS. 1 and 2.

DETAILED DESCRIPTION

[0053] The present disclosure will now be described more specifically with reference to the following embodiments. It is to be noted that the following description is presented herein for purpose of illustration and description only. It is not intended to be exhaustive or to be limited to the precise form disclosed.

[0054] FIG. 1 shows an embodiment of a sensor unit 1 of the present disclosure in sectional view. A sensor element 2 is fastened to a transparent support 3, in the example shown with a double-sided adhesive tape 21. Via a membrane 4, the sensor element 2 is in diffusive contact with an auxiliary medium 51, which is located in a reservoir 5. The reservoir 5 is delimited, apart from the membrane 4, by a cap 6, which is formed as a cavity in a foil 61. The foil 61 extends into a handle 62, which is only partially shown here. The membrane 4 is fixed to the foil 61 by a weld ring 41. Furthermore, the foil 61 is fastened to the support 3 via a weld ring 31. In the illustrated state, the sensor unit 1 is in the preparation state. The sensor element 2 is protected by the cap 6, in particular during irradiation for the purpose of sterilization. The diffusive contact between auxiliary medium 51 and sensor element 2 facilitated by membrane 4 ensures a wetting of sensor element 2 in the preparation state in which sensor unit 1 can be stored.

[0055] The foil 61 can be an aluminum foil or a plastic-aluminum composite foil, for example, low-density polyethylene (LDPE). The support 3 may be, for example, a cycloolefin copolymer (COC). The membrane 4 may be, for example, microporous polypropylene (PP).

[0056] The transparent support 3 allows light to pass through the support 3 to the sensor element 2 and/or to detect light from the sensor element 2 through the support 3 for the purpose of evaluating the optical behavior of the sensor element 2. This implies that “transparent” here means that the support 3 is transparent for relevant light wavelengths to such an extent that the measurement of the analyte is possible with a desired accuracy. In the same sense, the adhesive tape 21 must then also be transparent.

[0057] In the illustration, the membrane 4 is fastened to the foil 61 via weld ring 41. It would also be conceivable, for example, to fasten the membrane 4 with a clamping ring, wherein the clamping ring is then fastened to the foil 61, for example via a weld ring.

[0058] FIG. 2 shows a plan view of the sensor unit 1 shown in FIG. 1. Here, the handle 62 is shown completely. The sensor element 2 is indicated by a circle. By the handle 62, cf. FIG. 1, the cap 6 together with the reservoir 5 and the membrane 4 can be pulled off the support 3, wherein the connection provided by the weld ring 31 is released. More precisely, the weld ring 31 detaches from the support 3 and remains on the foil 61, while the connection provided by the weld ring 41 remains. The sensor element 2 is then accessible from outside the sensor unit 1. The sensor unit 1 is thus set into the measurement state.

[0059] FIG. 3 shows a sectional view of a further embodiment of the sensor unit 1. The sensor unit 1 is shown in the preparation state. The sensor unit 1 comprises a sensor part 20, to which the sensor element 2 is attached by support 3. The sensor unit 1 further comprises a reservoir part 50 in which the reservoir 5 is formed. The reservoir 5 is delimited on one side by the membrane 4 and likewise attached to the reservoir part 50. The reservoir 5 is delimited on other sides by a metallized foil 52. The foil 52 acts as a diffusion barrier. A channel 22 for a light guide is formed in the sensor part 20. A light guide can be passed to the support 3 via the channel 22 in order to guide light to the sensor element 2 through the light guide and via the support 3 and/or to guide light away from the sensor element 2. This serves to detect the optical behavior of the sensor substance in the sensor element 2. The reservoir part 50 furthermore has an opening 54, through which contact between a sample and the sensor element 2 is possible in the measurement state. In the preparation state shown, there is diffusive contact between the sensor element 2 and the reservoir 5 via the membrane 4, so that the auxiliary medium (not shown here) in the reservoir 5 or components thereof can reach the sensor element 2 by diffusion through the membrane 4.

[0060] Sensor part 20 and reservoir part 50 are rotatable relative to one another about an axis 200. By such a rotation, sensor unit 1 can be set into the measurement state shown in FIG. 4. Sensor part 20 and reservoir part 50 are sealed against one another by O-rings 53. Flange 56 on reservoir part 50 serves to fasten sensor unit 1 to a sample vessel. Depending on the configuration of the sample vessel and sensor unit 1, this fastening can be carried out differently. If, for example, the sample vessel is a bag made of plastic and the flange 56 is also made of plastic, then the bag and flange may be welded or else glued. If the sample vessel has a stronger wall, the flange may be connected to the wall, for example, by a screw connection or via a bayonet lock. In the embodiment shown, a retaining bracket 70 ensures the cohesion of reservoir part 50 and sensor part 20.

[0061] FIG. 4 shows the sensor unit 1 from FIG. 3 in the measurement state. Here, a sample can now reach the sensor element 2 through opening 54. In contrast, there no longer is diffusive contact between the reservoir 5 and the sensor element 2.

[0062] FIGS. 5A-C show a sequence of three stages before a measurement with a sensor unit 1 according to the present disclosure. The sensor unit 1, which corresponds to the embodiment shown in FIGS. 1 and 2, is inserted into a sample vessel 100, for instance adhesively bonded to the base of the sample vessel 100. At FIG. 5A, cap 6 covers the sensor element and the reservoir (not shown here, see FIGS. 1 and 2) and the handle 62 is angled and passed out of the sample vessel 100. In this state, the sample vessel 100 together with the sensor unit 1 can be irradiated for sterilization, and the sensor element is protected by the cap 6. The sample vessel 100 together with the sensor unit 1 can also be stored. In FIG. 5B, the cap 6 together with the reservoir and membrane (see FIGS. 1 and 2) is pulled off the sensor unit 1 by a force 65 on the handle 62, thus reaching the third stage, as shown in FIG. 5C. In FIG. 5C, the sensor element 2, fastened to the support 3, is accessible from the interior of the sample vessel 100.

[0063] The sample vessel 100 can then be filled with a sample. Subsequently, the measurement can be performed using the sensor element 2.

[0064] It is believed that the present disclosure and many of its attendant advantages will be understood by the foregoing description, and it will be apparent that various changes may be made in the form, construction, number and arrangement of the components without departing from the disclosed subject matter. The form described is merely explanatory, and it is the intention of the following claims to encompass and include such changes. Accordingly, the scope of the invention should be limited only by the claims appended hereto.