Abstract
The invention relates to a sealed bag containing a reference fluid for the calibration or quality control of a sensor element for measuring body fluid parameters, the bag comprising peripheral walls of a first layered material. The bag further comprises an access port formed by an opening in the first layered material, wherein the opening is sealed by a cover of a second layered material, wherein the second layered material is more resistant to oxidation by the reference fluid than the first layered material.
Claims
1. A sealed bag containing a reference fluid for the calibration or quality control of a sensor element for measuring body fluid parameters, the bag comprising peripheral walls of a first layered material; wherein the bag further comprises an access port formed by an opening in the first layered material, wherein the opening is sealed by a cover of a second layered material, and wherein the second layered material is more resistant to oxidation by the reference fluid than the first layered material.
2. The sealed bag according to claim 1, wherein the first layered material comprises an inner polymer layer in contact with the reference fluid, an outer polymer layer, and a gas barrier layer between the inner and outer polymer layers.
3. The sealed bag according to claim 2, wherein the gas barrier layer of the first layered material is made of aluminium.
4. The sealed bag according to claim 1, wherein the inner polymer layer of the first layered material is made of a heat-sealable material.
5. The sealed bag according to claim 1, wherein an inner polymer layer of the first layered material is made of polyolefin.
6. The sealed bag according to claim 1, wherein an outer polymer layer of the first layered material is made of polyethylene terephthalate or polyamide.
7. The sealed bag according to claim 1, wherein the second layered material comprises at least a first polymer layer, a second polymer layer, and a first gas barrier layer between the first and second polymer layers.
8. The sealed bag according to claim 7, wherein the first gas barrier layer of the second layered material is made of aluminium oxide or silicon oxide.
9. The sealed bag according to claim 7, wherein the first polymer layer of the second layered material is made of a heat-sealable material.
10. The sealed bag according to claim 7, wherein the first polymer layer of the second layered material is made of polyolefin.
11. The sealed bag according to claim 7, wherein the second polymer layer of the second layered material is made of polyethylene terephthalate or polyamide.
12. The sealed bag according to claim 7, wherein the second layered material comprises at least a first additional polymer layer between the first and second polymer layers.
13. The sealed bag according to claim 7, wherein the second layered material further comprises a second gas barrier layer.
14. The sealed bag according to claim 13, wherein the second gas barrier layer of the second layered material is made of aluminium oxide or silicon oxide.
15. The sealed bag according to claim 12, wherein the second layered material further comprises a second additional polymer layer between the first and second polymer layers.
16. The sealed bag according to claim 12, wherein the first and/or second additional polymer layers of the second layered material are made of polyethylene terephthalate.
17. The sealed bag according to claim 1, wherein at least one of the layers composing the first layered material is a bi-axially oriented polymer.
18. The sealed bag according to claim 1, wherein at least one of the layers composing the second layered material is a bi-axially oriented polymer.
19. The sealed bag according to claim 1, wherein the cover is attached to the peripheral wall from the inside of the bag.
20. The sealed bag according to claim 1, wherein the cover is attached to an attachment portion of the peripheral wall at the periphery around the opening.
21. The sealed bag according to claim 1, wherein the first and second layered materials are joined to each other with the inner polymer layer of the first layered material in sealing engagement with the first polymer layer of the second layered material.
22. The sealed bag according to claim 1, wherein the reference fluid comprises at least one analyte selected from the group consisting of CO.sub.2, O.sub.2, K.sup.+, Na.sup.+, Ca.sup.2+, Cl.sup., glucose, lactate, haemoglobin, creatinine, creatine and urea.
23. The sealed bag according to claim 1, wherein the reference fluid comprises creatinine and/or creatine.
24. The sealed bag according to claim 1, wherein the reference fluid comprises oxygen.
25. The sealed bag according to claim 1, further comprising a sealing element adapted for being pierced by an access probe.
26. The sealed bag according to claim 1, further comprising a support element attached to an inner surface of the bag.
27. The sealed bag according to claim 26, wherein the support element and the inner surface of the bag are made from the same material.
28. The sealed bag according to claim 26, wherein the support element comprises at least one passage for receiving an access probe.
29. The sealed bag according to claim 28, wherein the opening is aligned with the passage through the support element.
30. The sealed bag according to claim 26, wherein the cover is arranged between the support element and the peripheral wall around the opening.
31. A reference fluid bag assembly comprising a sealed bag according to claim 1, and an access probe adapted for insertion into the sealed bag through the access port by piercing the second layered material, the access probe being further adapted for withdrawing the reference liquid there through.
32. A container adapted for providing an analysis instrument for measuring parameters of a body fluid with a plurality of reference fluids for sensor calibration and/or sensor quality control, the container comprising at least one bag assembly according to claim 31.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0075] Preferred embodiments of the invention will be described in more detail in connection with the appended drawings, which show schematically in
[0076] FIG. 1 an embodiment of a sealed bag with an access system;
[0077] FIG. 2 a container with a plurality of sealed bags according to the embodiment of FIG. 1;
[0078] FIG. 3 a support element for use with a sealed bag according to some embodiments of the invention;
[0079] FIG. 4 a cross-sectional view of a sealed bag according to some embodiments of the invention, with a support element and a sealing element;
[0080] FIG. 5 a side elevation detail of a sealed bag with an access port according to one embodiment;
[0081] FIG. 6 a top elevation detail of the sealed bag of FIG. 5;
[0082] FIG. 7 a cross-sectional detail of the sealed bag of FIG. 6 along line VII-VII;
[0083] FIG. 8 cross-sectional detail of a first layered material according to one embodiment; and in
[0084] FIG. 9 a cross-sectional detail of a second layered material according to one embodiment.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0085] FIG. 1 shows a simplified depiction of a sealed bag 4 according to the invention, having an access system. The sealed bag 4 with access system is a bag assembly 1. The bag assembly 1 comprises a sealed bag 4 shaped as an envelope and containing a reference fluid and a support element (not visible). The sealed bag 4 has heat-sealed joints 5, 6 at the end-parts and along the side 7 of the bag 4. The bag has an access port 100 formed as an opening in the peripheral walls of the bag. The opening is sealed by a cover. The access port 100 defines an access location where an access probe 9 may penetrate the bag for withdrawing the reference fluid. The cover is made of materials that are resistant to oxidation by the reference fluid even when broken, e.g. by an access probe 9. Thereby the issue of parasitic hydrogen generation is overcome. The bag assembly 1 is furthermore provided with a sealing element 8 capable of sealing an opening in the bag pierced by an access probe 9 as indicated in the upper part of the figure. The sealing element 8 is placed at the access location defined by the access port 100.
[0086] The access probe 9 may be connected to a lid or other element (not shown) of a container. The sealing element 8 is made from butyl rubber and the access probe is made from ABS in this specific embodiment.
[0087] FIG. 2 depicts a container 2 in the shape of a box-like member and lid 3. The box-like member and the lid 3 is made from ABS. The box-like member contains several sealed bags 4 of which at least one is a sealed bag 4 according to the invention. The lid 3 may comprise access probes (not shown) for piercing the sealed bags 4 and further devices (not shown) for connecting the sealed bags 4 to a sample chamber of an analysis instrument with e.g. a creatine and/or creatinine sensor, a glucose sensor, and/or a lactate sensor.
[0088] FIG. 3 depicts a support element 10 for use in a bag assembly 1. The support element 10 is shaped as a longitudinal element with rounded ends 11, 12. Furthermore, the support element 10 is equipped with passages in the form of holes 13, 14 positioned symmetrically with respect to each end. The holes 13, 14 are intended to receive an access probe for withdrawal of reference fluid from a sealed bag. Indeed, one hole would be sufficient, however, the two holes 13, 14 positioned symmetrically with respect to each end of the support element 10 facilitate the production and mounting of the support element 10.
[0089] In FIG. 4, a support element 10 is mounted in the interior of a sealed bag 4. The support element 10 is mounted on the inner wall 15 of the sealed bag 4, such that it is in contact with the inner polymer layer. The bag has an access port 100 formed as an opening in the peripheral walls, which is sealed by a cover as described above. On the outer wall 16 of the sealed bag 4 is mounted a sealing element 8 at the location of the hole 13 in the support element 10.
[0090] Details of the access port 100 are now explained with reference to the schematic drawings in FIGS. 5-7. An envelope shaped sealed bag 4 has peripheral walls made of a first layered material. The peripheral walls have an opening, here shown as a circular opening 101, which is sealed by a cover 20 attached to the peripheral walls from the inside. The cover is made of a second layered material. The second layered material, including any internal layers of the second layered material, is made of materials that are more resistant to oxidation by the reference fluid than the first layered material. A welding seam 102 is formed between the cover 20 and the peripheral walls of the bag 4 at attachment portions thereof, thereby sealing the cover 20 to the peripheral walls. A support element 10 may be attached to an inner surface of the peripheral walls of the bag 4 as described before. A first end 11 of the support element has a passage 13 adapted for receiving and guiding an access probe there through when the access probe pierces the bag 4. The passage 13 is aligned with the opening 101 of the access port 100.
[0091] FIG. 8 shows one embodiment of a first layered material 110 for forming the peripheral walls of the sealed bag 4. The first layered material 110 has an inner polymer layer 111 adapted for contact with the reference fluid, an outer polymer layer 112 adapted for forming an outside face of the bag 4, and a gas barrier layer 113 arranged between the inner polymer layer 111 and the outer polymer layer 112. The inner polymer layer 111 of the first layered material 110 is made of a heat-sealable material, such as polyethylene (PE). The outer polymer layer 112 of the first layered material 110 is made of polyethylene terephthalate (PETP) or polyamide (PA). The gas diffusion barrier layer 113 of the first layered material is typically made of aluminium (Al). While the layer 113 provides a reliable gas diffusion barrier, it may oxidise when exposed to the reference fluid, e.g. upon being pierced by an access probe for withdrawing the reference fluid. As a consequence, hydrogen is produced which may cause interference with calibration and quality control procedures. To avoid such interference, the access port 100 features a cover 20 made of a second layered material that is more resistant to oxidation by the reference fluid than the first layered material.
[0092] FIG. 9 shows one embodiment of a second layered material 120 for forming the cover 20 of the access port 100. The second layered material 120 has a first polymer layer 121, a second polymer layer 122, and a first gas barrier layer 123 between the first polymer layer 121 and the second polymer layer 122. The first polymer layer 121 of the second layered material 120 is made of a heat-sealable material, such as polyethylene (PE). The second polymer layer 122 of the second layered material 120 is made of polyamide (PA). The first gas barrier layer 123 of the second layered material 120 is made of aluminium oxide (AlOx). The second layered material 120 further comprises a first additional polymer layer 124 between the first polymer layer 121 and the second polymer layer 122. The first additional polymer layer 124 acts as a support layer for the first gas barrier layer 123. The second layered material 120 further comprises a second gas barrier layer 125 between the first polymer layer 121 and the second polymer layer 122, which is separated from the first gas barrier 123 layer by the first additional polymer layer 124. The second gas barrier layer 125 of the second layered material 120 is made of aluminium oxide (AlOx). The second layered material 120 further comprises a second additional polymer layer 126 between the first polymer layer 121 and the second polymer layer 122. The second additional polymer layer 126 acts as a support layer for the second gas barrier layer 125. The first and second additional polymer layers 124, 126 are made of polyethylene terephthalate (PETP). The second layered material 120 thus has the following layer sequence going from the first polymer layer 121 to the second polymer layer 122: first polymer layer 121; first gas barrier layer 123; first additional polymer layer 124, second gas barrier layer 125, second additional polymer layer 126; second polymer layer 122. The gas barrier layers 123, 125 of the second layered material 120 are made of aluminium oxide (AlOx), which is more resistant to oxidation by aqueous reference solutions than aluminium (Al), which is used for the gas barrier 113 in the first layered material 110.
[0093] The polymer layers 111, 112 of the first layered material 110 and the polymer layers 121, 122, 124, 126 of the second layered material 120 are made of bi-axial polymer material.
Example 1
[0094] According to this example, a first layered material is provided. The first layered material has a layer sequence as described above with respect to FIG. 8, and layer thicknesses and materials as follows from Table 1, wherein adhesive layers for binding the layers together, typically polyurethane based adhesive layers, are omitted:
TABLE-US-00001 TABLE 1 Layer Material Thickness inner polymer PE 80 m gas barrier Al 9 m outer polymer PETP 12 m
Example 2
[0095] According to this example, a second layered material is provided. The second layered material has a layer sequence as described above with respect to FIG. 9, and layer thicknesses and materials as follows from Table 2, wherein adhesive layers for binding the layers together, typically polyurethane based adhesive layers, are omitted:
TABLE-US-00002 TABLE 2 Layer Material Thickness first polymer PE 80 m first gas barrier AlOx 50 nm first additional polymer PETP 12 m second gas barrier AlOx 50 nm second additional polymer PETP 12 m outer polymer PA 15 m
Example 3
[0096] According to this example, a container with a plurality of reference fluid bag assemblies is disclosed. The container may be a container as schematically shown in FIG. 2. The container is for providing a plurality of different reference fluids for the calibration and/or quality control procedures to be performed at regular intervals in an instrument for the analysis of body fluids, such as blood or urine, with respect to different parameters. The instrument is typically one that is adapted to measure different parameters simultaneously on the same sample using an array of sensors including electrochemical sensors, such as amperometric sensors, which are integrated within the same sample chamber. The different reference fluids are contained in envelope shaped sealed bags. The bags remain sealed for safe storage and transportation. Upon installation, the sealed membranes forming the bags are perforated by means of cooperating access probes for allowing withdrawal of the respective reference fluids from the bag. Different reference fluids may be provided in the same cassette container, wherein each reference fluid is contained in its own sealed bag placed at a specified position in the cassette container. At least one of the reference fluids is provided in a sealed bag according to an embodiment of the invention with an access port formed by an opening in a first layered material defining peripheral walls, wherein the opening is sealed by a cover of a second layered material, and wherein the second layered material is more resistant to oxidation by the reference fluid than the first layered material. For example, the reference fluid may have a relatively high content of creatinine of above 300 M, a relatively high content of creatine of above 300 M, and a relatively low content of oxygen with a partial pressure of between 0 mmHg and 20 mmHg.
[0097] It is to be understood that the present disclosure includes permutations of combinations of the optional features set out in the embodiments described above. In particular, it is to be understood that the features set out in the appended dependent claims are disclosed in combination with any other relevant independent claims that may be provided, and that this disclosure is not limited to only the combination of the features of those dependent claims with the independent claim from which they originally depend.
