Waste bag for biological waste, such as immunoassay waste

Abstract

A waste bag for biological waste from a blood analysis device is provided, as well as a cartridge including the waste bag, and a blood analysis device including the bag or the cartridge. The bag includes an envelope, a vent on an upper surface of the envelope for discharging gas, and an opening for receiving liquid waste and gas waste. The bag includes a superabsorbent polymer contained in the envelope, the superabsorbent polymer being in the form of beads.

Description

Technical Field

[0001] The present invention provides a waste bag for biological waste from a blood analysis device, a cassette including the waste bag, and a blood analyzer including the bag or the cassette. The bag includes an envelope, a vent for discharging gas on the upper surface of the envelope, and an opening for receiving liquid waste and gas waste. The bag includes a superabsorbent polymer accommodated in the envelope, and the superabsorbent polymer is in the form of beads. Background Art

[0002] Blood analysis machines are widely used in the medical field to analyze various characteristics in human blood. (For convenience, the term "blood analyzer" will be used throughout this specification to refer to a blood analysis machine. However, it should be recognized that the present invention is not intended to be limited to blood analyzers and can be used in urine, mucus, spinal fluid, and sperm analysis machines.) A blood sample is taken from a patient, and the blood is transferred into a blood analyzer. Then, the blood analyzer is used to determine the levels of specific components (e.g., blood gases and electrolytes) found in the blood.

[0003] When the blood analyzer has completed the analysis of the blood sample, the waste blood is transferred to a waste container. In the blood analyzer, liquids are used for performing assays, for calibrating the analyzer, and for rinsing the blood analyzer after analyzing the blood sample. These liquids are also transferred to the waste container. Gases are also used to rinse the blood analyzer, and these gases are also transferred to the waste container.

[0004] Therefore, a large amount of liquid and gas may be transferred into the waste container. If not handled properly, the liquid and gas may spill or leak, or cause "swelling" in the waste container. The waste container should be able to manage the waste liquid and gas. It should also be disposable and replaceable in a hygienic manner and comply with hazardous waste regulations. Blood and blood components may coagulate even after being analyzed, which increases the risk of blockage at the inlet and / or outlet of the waste container.

[0005] Known waste containers include open trays made of molded plastic and may be insufficient to avoid spills and leaks. Other known solutions include waste bags that stand upright in the device, which are undesirable from the perspectives of liquid flow and replaceability of the waste bag. A waste bag for a portable blood analyzer is described in WO9743988A1. Another device facilitating waste disposal is described in WO2016096845.

[0006] Accordingly, there is a need for a waste container for a portable hematology analyzer that is disposable, lightweight, and compact, and that can manage large volumes of liquid and gas while substantially preventing spillage and / or leakage of waste fluids. Importantly, the waste container should effectively allow gas to escape, avoid clogging, while effectively retaining waste liquids. The present invention aims to provide such a waste container. Summary of the Invention

[0007] The inventors have found that effective waste containment and effective gas evacuation can be achieved in a waste bag for a hematology analyzer while avoiding clogging or blocking of the gas outlet and the waste inlet openings. Accordingly, there is provided a waste bag for biological waste from a blood analysis device,

[0008] The bag includes an envelope formed of a liquid and gas impermeable film material,

[0009] The envelope includes opposing upper and lower surfaces,

[0010] The bag further includes a gas outlet in the upper surface of the envelope, wherein the gas outlet is covered by a gas permeable, liquid impermeable membrane,

[0011] The bag further includes an opening for receiving liquid waste and gas waste,

[0012] wherein the bag includes a superabsorbent polymer contained within the envelope,

[0013] wherein the superabsorbent polymer is in the form of beads.

[0014] There is also provided a disposable cartridge for a blood analysis device, the cartridge including a waste bag as described herein. There is also provided an immunoassay analysis device including a cartridge as described herein or a waste bag as described herein.

[0015] Further aspects of the invention are presented in the following drawings, specification text, and appended claims. Brief Description of the Drawings

[0016] The technology is illustrated in the accompanying schematic drawings, wherein:

[0017] Figure 1 A perspective view of one embodiment of a waste bag according to the present invention is shown.

[0018] Figure 2 A perspective view of one embodiment of a cartridge according to the present invention is shown, the cartridge including a waste bag.

[0019] Figure 3A diagram showing superabsorbent polymer beads and how they might contact a membrane.

[0020] Figure 4 A picture showing a filled waste bag containing blood and assay buffer. Detailed Description

[0021] As described above, the present invention relates to a waste bag for biological waste from a blood connectivity analysis device.

[0022] The biological waste output from the blood analysis device is typically a mixture of blood and blood components (such as plasma), various assay liquids, calibrators, and flushing liquids and gases. These components can enter the waste bag in various orders and combinations, which means that containing liquids and separating gases is important.

[0023] The waste bag includes an envelope formed of a liquid- and gas-impermeable film material. In this way, liquid waste and gas waste are disposed of in a hygienic manner. Typically, the maximum volume of the envelope is between 500 - 2000 ml, preferably between 800 - 1200 ml.

[0024] Those skilled in the art know suitable liquid- and gas-impermeable film materials and techniques for forming the envelope. Suitable liquid- and gas-impermeable materials are polymer films such as polyethylene (PE) film or polypropylene (PP) film, which can be single-layer or multi-layer, and optionally are laminates of different layers. For maximum gas impermeability, the polymer film is suitably coated with, for example, a metal layer. The envelope can be formed by cutting, folding, gluing, welding (such as heat welding) the film material as needed. The structure and material of the envelope allow the waste bag to expand as needed during use, but to shrink and / or fold together before use, thus occupying less space.

[0025] The envelope includes opposite upper and lower surfaces. In a preferred embodiment, as Figure 1 shown, the envelope consists of opposite upper and lower surfaces, wherein the opposite upper and lower surfaces are sealed to each other around their respective edges - that is, the envelope is formed of two film materials that are joined to each other near the edges.

[0026] For ease of manufacture, it is preferred that the upper and lower surfaces of the envelope have substantially the same shape. Thus, the envelope can have a major extension in the X-Y plane, and the upper and lower surfaces have substantially the same geometry in the X-Y plane. The bag also includes an opening for receiving liquid waste and gas waste. Suitably, the opening in the bag for liquid waste and gas waste is located at or adjacent to the seal between the upper and lower surfaces. This arrangement ensures that when liquid and gas enter the envelope and cause it to expand, the opening rises from the lower surface of the envelope. Thus, the liquid is encouraged to flow away from the opening, reducing the likelihood of the opening becoming blocked.

[0027] The opening for receiving liquid waste and gas waste can include a valve arranged to allow liquid waste to enter the envelope via the opening while substantially preventing liquid waste from leaving the envelope via the opening. Suitably, as Figure 1 shown, the opening can include one or more connecting elements that allow the bag to be reversibly locked to the corresponding elements of the waste tube in the blood analysis device when the waste bag is inserted in place and unlocked when the waste bag is to be removed. Locking the connecting elements of the bag opening to the corresponding elements of the waste tube provides a liquid-tight connection. Suitable connecting elements can be push-fit connecting elements or bayonet connecting elements.

[0028] Suitably, the opening for receiving liquid waste and gas waste is not located in the upper surface of the envelope. In this configuration, the positions of the exhaust port and the opening are remote from each other.

[0029] Suitably, the bag does not include any internal barriers or walls. In other words, the bag is defined only by the upper and lower surfaces of the envelope. Specifically, the bag does not include any internal barriers or walls in the gas path between the opening and the exhaust port, such that waste liquid and gas can flow unimpeded between the opening and the exhaust port. This arrangement allows the waste to be freely distributed within the bag.

[0030] As described above, the bag also includes an exhaust port in the upper surface of the envelope for discharging gas. The exhaust port is covered by a gas-permeable, liquid-impermeable membrane. Suitable gas-permeable, liquid-impermeable membranes are hydrophobic membranes such as PTFE membranes or fluoropolymer-treated membranes. The bag can include more than one exhaust port, each covered by a gas-permeable, liquid-impermeable membrane.

[0031] Table 1 List of suitable membranes

[0032] Membrane type Supplier (Emflon®) PTFE membrane Pall Versapor® RC membrane Pall Glass fiber medium (hydrophobic) membrane Pall

[0033] The gas-permeable, liquid-impermeable membrane prevents liquid from leaving the bag, but may become clogged or blocked if exposed to liquid, solid, and semi-solid waste. The clogged membrane prevents gas from flowing out of the bag, which can cause the bag to expand undesirably.

[0034] Preferably, the vent is substantially located at the center of the upper surface of the envelope. The "center" of the upper surface is defined as the point that is as far as possible from the opposite edges of the upper surface as determined in all directions. By having the vent in this position, the bag is allowed to expand as much as possible, creating a "dome" effect where the vent is located at the uppermost part.

[0035] The bag includes a superabsorbent polymer contained in the envelope, where the superabsorbent polymer is in the form of beads. Superabsorbent polymers (SAPs) are known in the field of personal hygiene products and are known to be able to absorb 200 - 300 times their own weight of liquid water. Suitable superabsorbent polymers can be selected from: polyacrylic acid (PAA), poly(meth)acrylic acid (PMA), and esters of PAA or PMA, as well as their copolymers or block copolymers. Polyacrylamide, either alone or as a copolymer or block copolymer, is also suitable. A person skilled in the art can select the SAP based on, for example, molecular weight or degree of crosslinking to optimize properties such as swelling.

[0036] By isolating liquid waste in the superabsorbent polymer, the risk of blood spillage and exposure to human materials is reduced.

[0037] Furthermore, since the superabsorbent polymer is in the form of beads, the superabsorbent polymer beads can move relatively freely within the bag and thus absorb liquid as needed. The superabsorbent polymer beads themselves, for example by having a substantially spherical shape, have a relatively small contact area with the gas-permeable, liquid-impermeable membrane. Thus, the membrane will not be submerged in liquid and will therefore maintain its venting performance. This is illustrated schematically in Figure 3 in the form of a schematic diagram.

[0038] Thus, agglomeration of the superabsorbent polymer (which can subsequently cause blockage of the openings and / or vents in the bag) can be avoided.

[0039] The superabsorbent polymer beads have the advantage that they can move smoothly past / over each other within the bag.

[0040] Suitably, the superabsorbent polymer beads have a substantially spherical shape. The superabsorbent polymer beads can have a three-dimensional geometry such as, but not limited to, spheres, hemispheres, ellipsoids, and / or volumetric polyhedra. The beads can be a mixture of various shapes. Preferably, the superabsorbent polymer beads have at least one curved surface.

[0041] This allows them to move smoothly past / over each other within the bag and minimizes the contact area with the membrane. Appropriately, during both the dry and wet phases, the surface friction between the beads and between the beads and the bag is low, enabling the beads to flow and move easily (i.e., freely flow) within the waste bag, which also helps to avoid blockage or clogging of the bag opening.

[0042] Appropriately, the superabsorbent polymer beads have an average particle size between 2.0 - 3.5 mm, preferably between 2.5 - 3.0 mm, in the dry state. A suitable supplier of SAP beads is Demi Co. Ltd.

[0043] A disposable cartridge for a blood analysis device is also provided, the cartridge including a waste bag as described herein. The cartridge is Figure 2 schematically shown in and has a general form of a "drawer" which is designed to be inserted into and removed from the lower part of the blood analysis device.

[0044] The disposable cartridge can be formed as a single piece of molded plastic or can be formed from plastic elements joined (welded or glued) together. The disposable cartridge will typically be provided in the form of a sealed unit (i.e., the base, walls, and lid are joined together such that it cannot be opened without breaking the cartridge).

[0045] It includes a substantially flat base, at least one side wall (e.g., 2, 3, or 4 side walls), and a substantially flat lid, wherein the base, the at least one side wall, and the lid define a substantially enclosed volume including the waste bag, and wherein the waste bag is arranged such that the vent of the waste bag is arranged furthest from the base of the cartridge.

[0046] In addition to the waste bag, the cartridge can also include one or more, and preferably two or more, and up to 9 buffer bags. The buffer bags contain the buffer liquid required to perform the analysis in the analysis device. Thus, the cartridge provides the buffer liquid for the analysis device. In the case where the analysis device is an immunoassay analysis device, the buffer bags will be assay buffer bags. By providing buffer bags in the cartridge, a closed system is obtained that contains buffer bags and also a waste bag for waste collection. This means that the user never has to directly contact the reagents, used samples, or any used reagents.

[0047] Appropriately, the waste bag has an internal volume equal to or greater than the total internal volume of all the assay buffer bags in the cartridge such that once used, all the assay buffer liquid can be contained within the waste bag.

[0048] In Figure 2In the illustrated embodiment, the waste bag is at least partially wrapped around the buffer bag in the cartridge such that a first portion of the waste bag is located between the buffer bag and the lid of the cartridge, and a second portion of the waste bag is located between the assay buffer bag and the base of the cartridge. Suitably, the vent of the waste bag is located in the first portion of the waste bag, and suitably, the opening of the waste bag is located in the second portion of the waste bag. This allows the openings for liquid and gaseous waste to be located at the bottom most, i.e., closest to the base, in the cartridge, while the vent can be located at the top most. In one aspect, the blood analysis device is an immunoassay analysis device. Accordingly, the present invention provides an immunoassay analysis device comprising a cartridge as defined herein or a waste bag as defined herein.

[0049] Description of the Drawings

[0050] Figure 1 Fig. shows a schematic perspective view of a waste bag (10) according to the present invention. The bag (10) comprises an envelope (12) of a liquid and gas impermeable film material. As shown, the envelope (12) comprises opposite upper (12a) and lower (12b) surfaces which are connected to each other via a seal (21) (i.e., a sealed edge). In Figure 1 the embodiment, only the upper and lower surfaces are present. The vent (14) is located on the upper surface of the envelope and is covered by a gas permeable, liquid impermeable membrane (16). The opening (18) is arranged for receiving liquid and gaseous waste into the bag (10). The bag comprises superabsorbent polymer (20) in the form of beads housed in the envelope. Figure 1 The waste bag (10) in is shown in a folded configuration ready to be accommodated within a cartridge (100).

[0051] Figure 2 Fig. shows a cartridge (100) according to the present invention (the lid is not shown for clarity). Figure 2 The upper figure in shows how the waste bag (10) is folded near the buffer bag (110); in this case, two buffer bags (110) are shown. Figure 2 The lower figure in shows the unfolded configuration showing how the waste bag (10) "wraps around" the buffer bag (110).

[0052] Figure 3 Fig. shows a hypothetical image of how the beads (20) of the superabsorbent polymer form spaces between each other and with the gas permeable, liquid impermeable membrane (16). Thus gas can pass through the channels between individual beads and between the beads and the membrane.

[0053] Figure 4Shows a photograph of a full waste bag (10) which has a liquid-impermeable membrane (16) and superabsorbent polymer beads (20, 20a) containing blood and assay buffer. Small spots (30) inside the membrane (16, a disc welded to the bag) indicate minimal blockage. In this way, the photograph shows that this membrane (16) still has sufficient gas-exhausting capacity. Example

[0054] Bead size test:

[0055] Test protocol

[0056] 1. A transparent folded waste bag is internally assembled with superabsorbent polymer beads from Demi and is ready for testing.

[0057] 2. Prepare a 1.2 L mixture of assay buffer and blood at a ratio of 120 (assay buffer) : 1 (blood) and inject it into the assay buffer bag of each solution pack.

[0058] 3. Assemble a solution pack including the folded waste bag and the assay buffer bag and get it ready for testing.

[0059] 4. Set up the test bench to test each solution pack according to the following steps:

[0060] a. Extract 4.5 mL of liquid from the assay buffer bag within 4 seconds, 35 times a day, and continue this action for a total of 7 days.

[0061] b. Inject all the liquid from step (a) into the waste bag at the same speed and frequency as in step (a). When the action in step (a) ends, stop injecting the liquid.

[0062] 5. After step 4, carefully remove the waste bag from the solution pack with the exhaust membrane side facing up. Visually inspect the state and appearance of the liquid absorbent material.

[0063] 6. Place the waste bag on top of a beaker while keeping the exhaust membrane side facing up.

[0064] 7. Make a small horizontal incision at the bottom of each tested waste bag. Place the waste bag for 24 hours to drain the remaining liquid.

[0065] 8. After step 7, measure and record the weight of the liquid drained from the waste bag.

[0066]

[0067] ( = Granular powder)

[0068] It can be seen that the superabsorbent polymer beads perform well compared to SAP powder and absorbent pads (such as absorbent pads used for packaging fresh meat). For the SAP beads of the present invention, no clogging of the exhaust film was observed.

[0069] The present invention has been described with reference to a plurality of embodiments. A person skilled in the art can combine elements from different embodiments as needed. All documents cited herein are incorporated by reference.

Claims

1. A waste bag (10) for biological waste from a blood analysis device, The bag (10) includes an envelope (12) formed of a liquid- and gas-impermeable film material, The envelope (12) includes opposite upper (12a) and lower (12b) surfaces, The bag (10) further includes an exhaust port (14) in the upper surface of the envelope (12) for exhausting gas, wherein the exhaust port (14) is covered by a gas-permeable, liquid-impermeable membrane (16), The bag (10) further includes an opening (18) for receiving liquid waste and gas waste, wherein, The bag (10) includes a superabsorbent polymer (20) housed in an envelope (12), wherein the superabsorbent polymer is in the form of beads (20a).

2. The waste bag (10) according to claim 1, wherein the envelope (12) consists of the opposite upper and lower surfaces (12a, 12b), and wherein the opposite upper and lower surfaces (12a, 12b) are sealed to each other near their respective edges.

3. The waste bag (10) according to claim 2, wherein the opening (18) for liquid waste and gas waste is located at or adjacent to the seal (21) between the upper and lower surfaces (12a, 12b).

4. The waste bag (10) according to any one of the preceding claims, wherein the envelope (12) has a major extension in the X-Y plane, and wherein the upper and lower surfaces (12a, 12b) have substantially the same geometry in the X-Y plane.

5. The waste bag (10) according to any one of the preceding claims, wherein the superabsorbent polymer beads (20a) have at least one curved surface and preferably have a substantially spherical shape.

6. The waste bag (10) according to any one of the preceding claims, wherein the superabsorbent polymer beads (20a) have an average particle size between 2.0 - 3.5 mm, preferably between 2.5 - 3.0 mm, in the dry state.

7. The waste bag (10) according to any one of the preceding claims, wherein the superabsorbent polymer beads (20a) are free-flowing within the waste bag (10).

8. The waste bag (10) according to any one of the preceding claims, wherein the opening (18) for receiving liquid waste and gaseous waste comprises a valve arranged to allow liquid waste to enter the envelope via the opening (18) while substantially preventing liquid waste from leaving the envelope via the opening (18).

9. The waste bag (10) according to any one of the preceding claims, wherein the opening (18) for receiving liquid waste and gaseous waste is not located in the upper surface (12a) of the envelope (12).

10. The waste bag (10) according to any one of the preceding claims, wherein the vent (14) is substantially located at the center of the upper surface (12a) of the envelope (12).

11. A disposable cartridge (100) for a blood analysis device, the cartridge comprising a waste bag (10) according to any one of the preceding claims.

12. The cartridge (100) according to claim 11, the cartridge comprising a substantially flat base, at least one side wall and a substantially flat lid, wherein the base, the at least one side wall and the lid define a substantially enclosed volume including the waste bag (10), wherein the vent (14) of the waste bag (10) is arranged furthest from the base of the cartridge (100).

13. The cartridge (100) according to any one of claims 11 - 12, further comprising one or more, and preferably two or more, and up to nine buffer bags (110).

14. The cartridge (100) according to any one of claims 11 - 13, wherein in the cartridge (100) the waste bag (10) has an internal volume equal to or greater than the total internal volume of all assay buffer bags (110).

15. An immunoassay analysis device comprising a cartridge (100) according to any one of claims 10 - 14 or a waste bag (10) according to any one of claims 1 - 10.

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