Extracting Liquid from a Punctureable Liquid Storage Container

Abstract

Embodiments described herein relate to a liquid extraction device for extracting liquid from a puncturable liquid storage container, the liquid extraction device comprising: a liquid storage container interface configured to provide a fluid connection to a volume of liquid in the liquid storage container, the liquid storage container interface comprising a liquid extraction outlet configured to allow liquid to be extracted from the liquid storage container; and a liquid extraction mechanism actuable from a first configuration to a second configuration, the liquid extraction mechanism configured to provide a pressure differential between a volume of gas in the liquid storage container and the liquid extraction outlet when the liquid extraction mechanism is actuated from the first configuration to the second configuration.

Description

[Technical field]

[0001] Field The present disclosure relates to devices and methods for extracting liquid from a puncturable liquid storage container, such as a blood collection tube. [Background technology]

[0002] background Point-of-care diagnostic devices are typically used to perform diagnostic tests, such as immunoassays, on biological samples (such as whole blood, serum, or plasma). To perform such diagnostic tests, the biological sample must be transferred to the diagnostic device. The diagnostic device is then inserted into an analytical device (or instrument) that controls the movement of fluids (e.g., biological samples, reagents, buffers, etc.) within the diagnostic device and performs the measurement of biomarkers to perform the diagnostic test.

[0003] Biological samples, such as whole blood or plasma, are typically collected from a subject using a puncturable liquid storage container, such as a blood collection tube, also commonly referred to as a venous blood tube or Vacutainer®. Existing systems for extracting liquid samples from a blood collection tube involve coupling the blood collection tube to a diagnostic device and then inserting the diagnostic device and coupled blood collection tube into an analytical device. Performing a diagnostic test can take several minutes, meaning that any remaining amount of biological sample in the blood collection tube cannot be used until the diagnostic device is removed from the analytical device after the diagnostic test is completed. Thus, a disadvantage of such existing systems is that the biological sample in the blood collection tube cannot be utilized until a particular diagnostic test is completed. A further disadvantage of existing systems is that the blood collection tube may contain solutions (e.g., control or calibration solutions) that may decompose if not maintained under certain conditions (e.g., a particular storage temperature such as 2-8°C).

[0004] Other existing systems require the blood collection tube to be uncapped before transferring the biological sample. For example, the biological sample may be manually transferred from the uncapped blood collection tube to the diagnostic device by a user (e.g., using a pipette). In an alternative example, an adapter device may be attached to the blood collection tube after uncapping the tube, and the adapter device is then attached to the diagnostic device to transfer the biological sample to the diagnostic device. Thus, a drawback of such existing systems is that a user of the diagnostic device must perform an additional manual operation to accomplish the transfer of the biological sample from the blood collection tube to the diagnostic device. Summary of the Invention [Problem to be solved by the invention]

[0005] Thus, there is a need for a device for extracting liquid from a liquid storage container (e.g., a blood collection tube) that allows for utilization of any remaining sample in the liquid storage container while a particular diagnostic test is being performed, minimizes handling time of the liquid storage container, and is easy to use. [Means for solving the problem]

[0006] overview This Summary introduces concepts that are described in more detail in the Detailed Description, and is not intended to identify essential features of the claimed subject matter, nor should it be used to limit the scope of the claimed subject matter.

[0007] According to one aspect of the present disclosure, there is provided a liquid extraction device for extracting liquid from a puncturable liquid storage container, the liquid extraction device comprising: a liquid storage container interface configured to provide a fluid connection to a volume of liquid in the liquid storage container, the liquid storage container interface comprising a liquid extraction outlet configured to allow liquid to be extracted from the liquid storage container; and a liquid extraction mechanism actuable from a first configuration to a second configuration, the liquid extraction mechanism configured to provide a pressure differential between a volume of gas in the liquid storage container and the liquid extraction outlet when the liquid extraction mechanism is actuated from the first configuration to the second configuration.

[0008] The liquid extraction device allows a user to activate a liquid extraction mechanism to extract liquid from a liquid storage container (such as a blood collection tube). Given that the liquid storage container interface is configured to provide a fluid connection to a volume of liquid in the liquid storage container, the user does not need to remove the cap of the blood collection tube or attach any form of adapter device to the blood collection tube. Thus, the liquid extraction device improves the ease of extracting liquid from a liquid storage container over existing systems.

[0009] The liquid extraction device may be suitable for extracting liquid from a blood collection tube and may include a blood collection tube interface configured to provide a fluid connection to a volume of liquid within the blood collection tube.

[0010] The liquid reservoir interface may be configured to allow removal of the liquid reservoir from the liquid reservoir interface after extraction of the liquid from the liquid reservoir, such that once a desired amount of liquid has been extracted from the liquid reservoir, the liquid reservoir may be reused while a particular diagnostic test is performed on the extracted liquid.

[0011] The liquid storage container interface can include at least one piercing element (e.g., a needle) configured to provide a fluid connection to a volume of liquid in the liquid storage container. The piercing element can also be configured to provide an attachment between the liquid extraction device and the liquid storage container. The piercing element can be configured to pierce the liquid storage container to provide a fluid connection to the volume of liquid. For example, the piercing element can be configured to pierce a septum of the liquid storage container, such as a septum of a blood collection tube.

[0012] The liquid extraction mechanism may comprise a piston movable within the receptacle, the piston being actuatable from a first configuration to a second configuration. The receptacle may be configured to receive a portion of a liquid storage container, such as an end of a blood collection tube, the end of the blood collection tube including a pierceable septum. The receptacle may comprise an outlet through which the extracted liquid from the liquid storage container may be removed. The outlet may be provided within an end wall of the receptacle. Alternatively, the outlet may be provided within a side wall of the receptacle. The liquid extraction device may further comprise a connector in fluid communication with the outlet, the connector configured to provide a fluid connection to a liquid processing device, such as a microfluidic cartridge.

[0013] The receptacle may include a septum defining an internal chamber within the receptacle. The liquid extraction outlet may be in fluid communication with the chamber within the receptacle. An outlet from the liquid extraction device may be provided in a wall of the chamber within the receptacle. The septum may include an opening comprising a pierceable seal, and the liquid reservoir interface is further configured to pierce the pierceable seal when the piston is in the second configuration to create a pressure differential between the volume of gas and the liquid extraction outlet.

[0014] The liquid reservoir interface may be attached to the piston such that the liquid reservoir interface may move with the piston when the piston is actuated from the first configuration to the second configuration.

[0015] The liquid extraction outlet can be in fluid communication with a chamber defined by the piston and the receptacle, the chamber being in fluid communication with the liquid extraction outlet. The chamber can be configured to store a quantity of liquid extracted from the liquid storage container.

[0016] The piston can be configured to increase a pressure of air in the chamber when the piston is actuated from the first configuration to the second configuration. To increase the pressure of air in the chamber, the piston can be configured to decrease a volume of the chamber when the piston is actuated from the first configuration to the second configuration.

[0017] The liquid extraction device may further comprise a sealing element configured to provide a seal between the piston and the receptacle when the piston is in the first configuration. The sealing element may seal the piston during actuation of the piston from the first configuration to the second configuration.

[0018] The liquid extraction mechanism can be configured to provide a pressure differential between the volume of gas within the collection tube and the liquid extraction outlet when the liquid extraction mechanism is in the second configuration.

[0019] The liquid extraction device may further comprise a seal failure element configured to fail the seal element when the piston is in the second configuration. When the seal element is failed, air may be released from the chamber, thereby creating a pressure differential between a liquid extraction outlet in fluid communication with the chamber and a volume of gas in the liquid storage container.

[0020] The seal-breaking element can include an opening configured to break the seal element when the piston is in the second configuration such that air within the chamber is released through the opening.

[0021] The liquid extraction device may further comprise an air filter configured to control the flow of air discharged through the opening. By controlling the flow of air discharged through the opening, the rate of change of pressure in the chamber (i.e., at the liquid extraction outlet) is slowed down. This slows down the extraction rate of liquid from the liquid storage container. In an example where the liquid storage container is a blood collection tube that stores a fixed volume of blood, slowing down the extraction rate of blood from the blood collection tube reduces the tendency for hemolysis to occur when blood is extracted.

[0022] The seal breaching element may be a first seal breaching element, and the liquid extraction device may further comprise a second seal breaching element configured to breach the seal element when the piston is actuated to a position between the first and second configurations. By including multiple seal elements, liquid may be extracted incrementally from the liquid storage container, thereby reducing a pressure differential created between the liquid extraction outlet and a volume of gas within the liquid storage container. In an example where the liquid storage container is a blood collection tube storing a fixed volume of blood, reducing the pressure differential reduces the tendency for hemolysis to occur during extraction of the blood.

[0023] The liquid extraction mechanism can be configured to provide a pressure difference between the volume of gas in the blood collection tube and the liquid extraction outlet during actuation of the liquid extraction mechanism from the first configuration to the second configuration. Providing a pressure difference during actuation of the liquid extraction mechanism allows liquid to be extracted from the liquid storage container when the liquid extraction mechanism is actuated. This means that liquid can be extracted from the liquid storage container using a lower pressure difference than in embodiments where a step change in pressure difference is provided. In an example where the liquid storage container is a blood collection tube storing a fixed volume of blood, reducing the pressure difference reduces the tendency for hemolysis to occur during the extraction of blood.

[0024] The piston can be configured to reduce a pressure in the chamber below a pressure of the volume of gas in the liquid storage container when the piston is actuated from the first configuration to the second configuration.

[0025] The liquid reservoir interface may comprise at least two needles, a first of the at least two needles configured to provide a fluid connection to a volume of liquid in the liquid reservoir, the first of the at least two needles in fluid communication with a liquid extraction outlet, a second of the at least two needles configured to provide a fluid connection to the liquid reservoir, and the liquid extraction mechanism configured to supply air through the second of the at least two needles. As in the above example, this allows liquid to be extracted during actuation of the liquid extraction mechanism, which in the example of blood extraction reduces the tendency for hemolysis to occur.

[0026] The liquid extraction device may further comprise an elastically deformable element configured to bias the piston outward from the first configuration towards the second configuration. The elastically deformable element allows for a controlled change in pressure, since the rate of change in pressure is dictated by the elastically deformable element, and not by the application of force by the user. Again, this may reduce the tendency for hemolysis to occur in instances where blood is extracted from a blood collection tube.

[0027] The liquid extraction device may further comprise at least one clip configured to hold the piston in a first configuration in which the elastically deformable element is in a deformed state. The at least one clip allows the liquid extraction mechanism to be activated by the action of the elastically deformable element when the piston is unclipped. In particular, the at least one clip avoids the need for a user to apply a downward force to deform the elastically deformable element. This minimizes the user action required to activate the liquid extraction mechanism, improving the ease of use of the device.

[0028] The liquid extraction device may further comprise a porous medium (e.g., a plasma separation membrane) in fluid communication with the liquid extraction outlet. Implementing a porous medium allows additional functionality to be provided by the liquid extraction device. As an example, implementing a plasma separation membrane allows plasma to be transferred to a liquid processing device such that diagnostic tests can be performed on the plasma, thereby avoiding the need for the liquid processing device to include a separate plasma separation membrane.

[0029] The liquid extraction mechanism may be external to the receptacle. The liquid extraction mechanism may comprise a plunger movable within the housing and an air transfer conduit in fluid communication with the housing and the receptacle, whereby actuation of the plunger transfers air from the housing to the receptacle (specifically, to the liquid storage container via the liquid extraction outlet). Alternatively, the liquid extraction mechanism may comprise a suction tab within the housing, the suction tab configured to transfer air from an internal chamber within the receptacle to the housing to provide a pressure differential between the volume of gas in the liquid storage container and the internal chamber.

[0030] According to another aspect of the present disclosure, there is provided a liquid extraction device for extracting liquid from a puncturable liquid storage container, the liquid extraction device comprising: a chamber having an outlet configured to vent the chamber; a first liquid storage container interface configured to provide a fluid connection to a volume of liquid in the liquid storage container, the first liquid storage container interface comprising a liquid extraction outlet in fluid communication with the chamber; and a second liquid storage container interface configured to provide a fluid connection to a volume of gas in the liquid storage container, the second liquid storage container interface configured to exhaust the volume of gas.

[0031] The liquid extraction device according to the present aspect allows liquid to be extracted from a liquid storage container using a device that does not have moving parts, and therefore the device has a simple structure and may be easier to manufacture.

[0032] The liquid extraction device may include a receptacle that houses a first liquid storage container interface and a second liquid storage container interface. The receptacle may be configured to receive a portion of a liquid storage container, such as an end of a blood collection tube, the end of the blood collection tube including a puncturable septum. A chamber may be provided within the receptacle. The ends of the first liquid storage container interface and the second liquid storage container interface may protrude into the chamber. The second liquid storage container interface may provide a fluid connection between the volume of gas and the chamber such that the second liquid storage container interface may vent the volume of gas to the chamber. Each liquid storage container interface may include a needle configured to puncture the liquid storage container (e.g., to puncture a septum of the blood collection tube).

[0033] According to a further aspect of the present disclosure, there is provided a liquid treatment apparatus comprising a liquid treatment device having one or more conduits and a liquid extraction device according to any of the above aspects, the liquid extraction device being in fluid communication with at least one of the one or more conduits.

[0034] The liquid treatment device may be suitable for use in performing diagnostic tests. The liquid extraction device may be integrated within the liquid treatment device. Alternatively, the liquid extraction device may be attachable to the liquid treatment device. For example, the liquid extraction device may be removably attachable to the liquid treatment device.

[0035] BRIEF DESCRIPTION OF THE DRAWINGS Specific embodiments are described below, by way of example only, and with reference to the accompanying drawings. [Brief description of the drawings]

[0036] [Figure 1] FIG. 2 is a schematic diagram of a first liquid extraction device in fluid communication with the cartridge. [Figure 2A] FIG. 2 is a schematic diagram of the attachment between the first liquid extraction device and the cartridge. [Figure 2B] FIG. 13 is a schematic diagram of the attachment between the second liquid extraction device and the cartridge. [Figure 3A] 1A-1C show a second liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 3B] 1A-1C show a second liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 3C] 1A-1C show a second liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 3D] 1A-1C show a second liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 4A] 1A-1D show a first liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 4B] 1A-1D show a first liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 4C] 1A-1D show a first liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 4D] 1A-1D show a first liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 5A] 13A-13D show a third liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 5B] 13A-13D show a third liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 5C]13A-13D show a third liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 5D] 13A-13D show a third liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 6A] 11A-11D show a fourth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 6B] 11A-11D show a fourth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 6C] 11A-11D show a fourth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 6D] 11A-11D show a fourth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 7A] 13A-13C show a fifth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 7B] 13A-13C show a fifth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 7C] 13A-13C show a fifth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 7D] 13A-13C show a fifth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 8A] 13A-13D show a sixth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 8B] 13A-13D show a sixth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 8C] 13A-13D show a sixth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 8D] 13A-13D show a sixth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 9A] 13A-13C show a seventh liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 9B] 13A-13C show a seventh liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 9C] 13A-13C show a seventh liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 9D] 13A-13C show a seventh liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 10A] 13A-13C show an eighth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 10B] 13A-13C show an eighth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 10C] 13A-13C show an eighth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 10D] 13A-13C show an eighth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 11A] 13A-13C show a ninth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 11B] 13A-13C show a ninth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 11C] 13A-13C show a ninth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 11D] 13A-13C show a ninth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 12A] 13A-13C show a tenth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 12B] 13A-13C show a tenth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 12C] 13A-13C show a tenth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 12D] 13A-13C show a tenth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 13A] 13A-13C show an eleventh liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 13B] 13A-13C show an eleventh liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 13C] 13A-13C show an eleventh liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 13D] 13A-13C show an eleventh liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 14A] 12A-12C show a twelfth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 14B]12A-12C show a twelfth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 14C] 12A-12C show a twelfth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 14D] 12A-12C show a twelfth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 15A] 13A-13C show a thirteenth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 15B] 13A-13C show a thirteenth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 15C] 13A-13C show a thirteenth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 15D] 13A-13C show a thirteenth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 15E] 13A-13C show a thirteenth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 16A] 13A-13C show a fourteenth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 16B] 13A-13C show a fourteenth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 16C] 13A-13C show a fourteenth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 16D] 13A-13C show a fourteenth liquid extraction device being used to extract liquid from a blood collection tube at various stages of the liquid extraction procedure. [Figure 17A] FIG. 16 shows a first embodiment of a plasma separation membrane configured for use with the liquid extraction device of FIGS. 3A-16D. [Figure 17B] FIG. 16B shows a second embodiment of a plasma separation membrane configured for use with the liquid extraction device of FIGS. 3A-16D. [Figure 17C] FIG. 16B shows a third embodiment of a plasma separation membrane configured for use with the liquid extraction device of FIGS. 3A-16D. [Figure 17D] FIG. 16B shows a fourth embodiment of a plasma separation membrane configured for use with the liquid extraction device of FIGS. 3A-16D. [Figure 18] FIG. 1 shows a blood collection tube being inserted vertically into a liquid extraction device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] Detailed Description Embodiments of the present disclosure are described below with particular reference to extracting liquid from blood collection tubes, however, it will be understood that the embodiments described herein can also be used to extract liquid from other sealed liquid storage containers into which a liquid collection interface (such as a needle) can be inserted.

[0038] FIG. 1 is a schematic diagram illustrating a first liquid extraction device 200 in fluid communication with a liquid treatment device in the form of a cartridge 100. As shown in FIG. 1, the cartridge 100 includes a number of chambers in fluid communication via a number of conduits 102. Specifically, the multiple chambers include a main chamber 104, a reagent chamber 106, a mixing chamber 108, a waste chamber 110, and a measurement chamber 112. The cartridge 100 also includes a number of valves 114, each of which controls the flow of fluid through a respective conduit 102. A sensor 116 is used to perform a measurement (e.g., an electrochemical measurement) on the solution in the measurement chamber 112.

[0039] Fluid flow between the chambers is controlled by an external pump 120 configured to apply positive or negative pressure to the main chamber 104 via a pump conduit 122. The positive or negative pressure distributes or aspirates fluid from one chamber to another depending on which of the valves 114 is open. For example, to aspirate reagent from the reagent chamber 106 to the main chamber 104 (e.g., to mix with a sample), the valve 114 between the reagent chamber 106 and the main chamber 104 is opened and a negative pressure is applied to the main chamber 104 by the pump 120.

[0040] The liquid extraction device 200 is in fluid communication with the cartridge 100 via the inlet conduit 14. As described in more detail below, the liquid extraction device 200 is configured to extract a liquid sample (e.g., blood) from a puncturable liquid storage container (e.g., a blood collection tube, not shown in FIG. 1). Once the liquid sample is extracted from the liquid storage container, it is transferred under pressure via the inlet conduit 14 to the metering chamber 16. The liquid sample can then be drawn from the metering chamber 16 through the outlet conduit 43 and into the main chamber 104 by applying negative pressure using the pump 120.

[0041] The sample can then be combined with one or more reagents in the main chamber 104 by aspirating the reagents from the reagent chamber 106 into the main chamber 104. The solution may be repeatedly transferred between the main chamber 104 and the mixing chamber 108 to mix the sample and reagents together. The solution can then be dispensed into the measurement chamber 112 where an electrochemical measurement is performed on the solution using the sensor 116. Any effluent from the main chamber 104 or the measurement chamber 112 can be transferred to the waste chamber 110.

[0042] As described in more detail below, the liquid extraction device 200 comprises a receptacle in the form of a cylinder 202 (or tube) in which a puncturable liquid storage container, such as a blood collection tube, is received. The liquid extraction device 200 also includes an actuatable liquid extraction mechanism in the form of a piston 204 that is actuatable within the cylinder 202 from a first liquid extraction mechanism configuration to a second liquid extraction mechanism configuration. In FIG. 1, the piston 204 is shown in the second liquid extraction mechanism configuration.

[0043] The liquid extraction device 200 includes a liquid reservoir interface (e.g., a blood collection tube interface) in the form of a needle 206 fixedly attached to a piston 204. The needle 206 is configured to pierce the liquid reservoir (e.g., by piercing a septum of the blood collection tube). The needle 206 includes a liquid extraction outlet 208 through which liquid extracted from the blood collection tube can flow.

[0044] The cylinder 202 also includes an outlet 216 that allows liquid to be removed from the liquid extraction device 200 upon its extraction from the blood collection tube. The outlet 216 is in fluid communication with the inlet conduit 14, thereby allowing liquid to be transferred from the liquid extraction device 200 to the cartridge 100.

[0045] The cartridge 100 further comprises a sample adequacy control chamber 24 that provides a visual indication to a user that a sufficient amount of liquid has been extracted from a liquid storage container (e.g., a blood collection tube). In particular, the sample adequacy control chamber 24 can provide a visual indication that a sufficient volume of liquid has been extracted for a particular diagnostic test. For example, as shown in FIG. 18, the sample adequacy control chamber 24 is configured to provide a visual indication through an optically transparent window 130 in a sidewall of the cartridge 100 that is located upward when the liquid extraction device 200 is in a vertical orientation (i.e., when the liquid extraction device 200 is used to extract liquid from a liquid storage container).

[0046] The sample adequacy control chamber 24 forms part of a first flow path in fluid communication with the inlet conduit 14 (which receives fluid extracted using the liquid extraction device 200). The cartridge 100 also includes a metering chamber 16 configured to store a specific volume of liquid. The first flow path includes the metering chamber 26, a connector conduit 22 providing a fluid connection between the metering chamber 16 and the sample adequacy control chamber 24, the sample adequacy control chamber 24, and an exhaust waste chamber 44 in fluid communication with the sample adequacy control chamber 24. The cartridge 100 further includes a second flow path comprising an outlet conduit 43 extending from an outlet port in the metering chamber 16. The outlet conduit 43 allows liquid to be aspirated into the main chamber 104 of the cartridge 100. Alternative embodiments may not include the metering chamber 16 or the connector conduit 22, in which case the outlet conduit 43 extends from an outlet port in the sample adequacy control chamber configured to meter a specific volume of liquid.

[0047] The second flow path (including the outlet conduit 43) provides a higher hydraulic resistance than the first flow path (which includes the sample adequacy control chamber 24, and optionally the metering chamber 16 and the outlet conduit 22). This means that the flow rate of liquid through the first flow path is higher than the flow rate through the second flow path. The higher flow rate through the first flow path means that liquid will flow into the sample adequacy control chamber 24 to provide a visual indication that a sufficient volume of liquid has been received, without filling the outlet conduit 43.

[0048] The outlet 216 of the liquid extraction device 200 shown in FIG. 1 is provided in the side wall of the cylinder 202. FIG. 2A shows the attachment between the first liquid extraction device 200 and the cartridge 100 in more detail. When the outlet 216 is provided in the side wall of the cylinder 202, fluid communication between the liquid extraction device 200 and the cartridge 100 can be provided by aligning the outlet 216 with a hole or via in the cartridge 100 that allows the passage of fluid into the inlet conduit 14. The alignment of the outlet 216 with the hole or via can be provided by attaching the liquid extraction device 200 to the cartridge 100 using a layer of adhesive (e.g., pressure sensitive adhesive).

[0049] 2B shows an alternative attachment of a liquid extraction device to a cartridge, in which a second liquid extraction device 300 is attached to the cartridge (e.g., cartridge 100). Similar to the liquid extraction device 200 shown in FIG 2A, the liquid extraction device 300 comprises a cylinder 302 in which a puncturable liquid storage container, such as a blood collection tube, is received.

[0050] The liquid extraction device 300 also includes a piston 304 that is movable from a first configuration to a second configuration within the cylinder 302. Attached to the piston 304 is a liquid reservoir interface (e.g., needle 306) that provides a path for air to enter the liquid reservoir and a path for liquid (e.g., blood) to exit the liquid reservoir.

[0051] However, in contrast to the liquid extraction device 200 shown in Figure 2A, the cylinder 302 includes an outlet 316 provided in an end wall 318 of the cylinder 302. As shown in Figure 2B, the outlet 316 in the cylinder 302 can be in fluid communication with a connector 322 protruding from a bottom of the cylinder 302. The connector 322 allows the liquid extraction device 300 to be attached to a cartridge by a push-fit type attachment (e.g., by inserting the connector 322 into a corresponding hole or opening in the cartridge), or by using a luer lock, or by any other suitable type of fluid connector.

[0052] It will be understood that these attachment mechanisms are not specific to the location of the outlet in the cylinder of the liquid extraction device. In particular, the liquid extraction device 300 shown in FIG. 2B may be attached to the cartridge using adhesive, and the liquid extraction device 200 shown in FIG. 2A may include a connector protruding from the side wall of the cylinder 202, allowing it to be attached to the cartridge 100 using a push-fit or luer lock mechanism, or any other suitable type of fluid connector. Alternatively, the liquid extraction devices 200, 300 shown in FIGS. 2A and 2B may be integrated into the cartridge. For example, the cylinders 202, 302 may be molded (or otherwise manufactured) with the cartridge 100.

[0053] Various embodiments of liquid extraction devices that can be used to extract a liquid sample (e.g., blood) from a puncturable liquid storage container (e.g., a blood collection tube) will now be described in more detail with reference to Figures 3A-17D.

[0054] An example of a blood collection tube that can be used with the embodiments shown in Figures 3A-17D is shown diagrammatically in Figure 3A. As shown in Figure 3A, blood collection tube 11 comprises a tubular container 13 sealed using a cap 15. Cap 15 comprises a septum 17 formed from a deformable material, such as rubber. Septum 17 is pierceable by a needle or cannula, thereby allowing the end of the needle or cannula to pass into the interior volume of tubular container 13. When the needle or cannula is removed from septum 17, the deformable material deforms to close the hole pierced by the needle or cannula, thereby resealing container 13. Blood collection tube 11 comprises a liquid volume 19 (e.g., blood) and a headspace that comprises a gas volume 21. Blood collection tube 10 comprises, for example, a Vacutainer® manufactured by Becton, Dickinson and Company, Franklin Lakes, New Jersey, USA.

[0055] 3A-3D show the second liquid extraction device 300 (shown in FIG. 2B) being used to extract liquid from the blood collection tube 11. FIG 3A shows the liquid extraction device 300 before the blood collection tube 11 is attached.

[0056] As described with reference to Figure 2B, the liquid extraction device 300 includes a receptacle in the form of a cylinder 302 (or tube) in which the blood collection tube 11 is received. The liquid extraction device 300 also includes an actuatable liquid extraction mechanism in the form of a piston 304 that is movable within the cylinder 302. The piston 304 is actuatable within the cylinder 302 from a first configuration (e.g., as shown in Figure 3B) to a second configuration (e.g., as shown in Figure 3D). Figure 3C shows the piston 304 between the first and second configurations.

[0057] The liquid extraction device 300 also includes a liquid reservoir interface configured to provide a fluid connection to the volume of liquid in the liquid reservoir. For example, as shown in this embodiment and in the embodiment described with reference to Figures 4A-17D, the liquid reservoir interface may be provided in the form of a blood collection tube interface. In the example shown in Figures 3A-3D, the blood collection tube interface is provided in the form of a needle 306. The needle 306 is fixedly attached to the piston 304, meaning that the needle 306 is movable together with the piston 304 in the cylinder 302. The needle 306 protrudes from the piston 304 and is configured to pierce the septum 17 of the blood collection tube 11, thereby providing a fluid connection to the volume of liquid 19 in the blood collection tube 11 and providing an attachment between the liquid extraction device 300 and the blood collection tube 11. The needle 306 comprises a liquid extraction outlet 308 through which the liquid extracted from the blood collection tube 11 can flow.

[0058] The piston 304 also includes a sealing element in the form of an O-ring seal 310 that extends around the circumference of the piston 304 at the bottom of the piston 304. The O-ring seal 310 forms a seal between the piston 304 and the cylinder 302 that prevents air from escaping from within the cylinder 302 when the piston 304 is in the position shown in Figures 3A-3C. The sealing element may alternatively be provided in the form of a molded plastic seal (i.e. molded with the piston 304) or an overmolded rubber seal.

[0059] The cylinder 302 in which the blood collection tube 11 is received includes an opening in the form of a recess 312 in an interior sidewall of the cylinder 302. The recess 312 extends around at least a portion of the circumference of the interior sidewall of the cylinder 302. The recess 312 provides a path for air to flow around the O-ring seal 310 when the piston 304 is moved to the second configuration shown in FIG. 3D. When the piston 304 is in the second configuration, the O-ring seal 310 is aligned with the recess 312, thereby allowing air to escape around the O-ring seal 310. As a result, the seal provided by the O-ring seal 310 is broken when the O-ring seal 310 is aligned with the recess 312 (i.e., when the piston 304 is in the second configuration).

[0060] The cylinder 302 also includes a stopper 314 that protrudes from the interior sidewall of the cylinder 302. The stopper 314 extends around at least a portion of the circumference of the interior wall. The stopper 314 prevents the piston 304 in the cylinder 302 from moving downward beyond the point at which the stopper 314 protrudes. The stopper 314 is provided to align the O-ring seal 310 of the piston 304 with the recess 312 of the cylinder 302. In particular, when the piston 304 abuts the stopper 314, the O-ring seal 310 is aligned with the recess 312 such that air can flow around the O-ring seal 310 through the recess 312. In the example shown in Figures 3A-3D, the stopper 314 is provided by a reduction in the cross-sectional area of ​​the interior volume of the cylinder 302. However, it will be appreciated that the stopper 314 may alternatively be provided in the form of a protrusion extending from the interior sidewall of the cylinder 302.

[0061] The cylinder 302 also comprises an outlet 316 that allows liquid to be removed from the liquid extraction device 300 upon its extraction from the blood collection tube 11. For example, the outlet 316 may be in fluid communication with a liquid processing device, such as a diagnostic cartridge (e.g., a microfluidic cartridge). Alternatively or additionally, the outlet 316 may comprise a valve that allows liquid to be extracted from the cylinder 302 via the outlet 316. Alternatively, the outlet 316 may comprise a seal that is punctured, ruptured, or torn when the liquid extraction device 300 is attached to the cartridge. In the example shown in Figures 3A-3D, the outlet 316 is located in an end wall 318 of the cylinder 302 and is in fluid communication with a connector 322 that provides attachment of the liquid extraction device 300 to the cartridge.

[0062] The cylinder 302 and the piston 304 together define a non-vented chamber 320 between the piston 304 and an end wall 318 of the cylinder 302. The liquid extraction outlet 308 is in fluid communication with the chamber 320. The volume of the chamber 320 decreases as the piston 304 moves toward the end wall 318 of the cylinder 302 (i.e., as the piston 304 moves from the first configuration to the second configuration). The stopper 314 defines a minimum volume of the chamber 320.

[0063] When the blood collection tube 11 is attached to the liquid extraction device 300 via the needle 306 , the chamber 320 is in fluid communication with the volume of liquid 19 via the needle 306 .

[0064] 3A-3D show a procedure for extracting liquid from a blood collection tube 11. As will be explained in more detail below, as the piston 304 moves from a first configuration to a second configuration, a pressure differential is created between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 308. Specifically, in the example shown in FIGS. 3A-3D, a pressure differential is created as the piston 304 is in the second configuration.

[0065] 3A shows the blood collection tube 11 disconnected from the liquid extraction device 300. To attach the blood collection tube 11 to the liquid extraction device 300, a user pushes the blood collection tube 11 down onto the needle 306 so that the needle 306 pierces the septum 17. At this point, shown in FIG. 3B, the needle 306 provides fluid communication between the volume of liquid 19 and the chamber 320. In the position shown in FIG. 3B (i.e., when the piston 304 is in the first configuration), there is no pressure difference between the volume of gas 21 and the liquid extraction outlet 308.

[0066] As the user applies further downward force to the blood collection tube 11, the piston 304 is displaced within the cylinder 302, decreasing the volume of the chamber 320, as shown in FIGURE 3C. Given that the chamber 320 is not vented, the decrease in the volume of the chamber 320 causes the pressure of the air in the chamber 320 to be higher than atmospheric pressure, because the O-ring seal 310 prevents air from escaping the chamber 320. This means that air is forced into the blood collection tube 11 through the needle 306, increasing the pressure of the volume of gas 21 within the blood collection tube 11.

[0067] Continuing to apply the downward force causes the piston 304 to move further downward, which further increases the pressure of the air in the chamber 320 and the blood collection tube 11 until the piston 304 reaches the second configuration shown in FIG. 3D. When the piston 304 is in the second configuration, the O-ring seal 310 is aligned with the recess 312 and is consequently broken, allowing the air to escape around the O-ring seal 310 through the recess 312. This means that the high pressure air in the chamber 320 is exhausted to the atmosphere. At this point, there is a pressure difference between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 308. Specifically, the pressure of the volume of gas 21 in the blood collection tube 11 is higher than the pressure at the liquid extraction outlet 308 (the same pressure as the chamber 320, i.e., atmospheric pressure). The pressure difference between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 308 pushes the liquid through the needle 306 and into the chamber 320 through the liquid extraction outlet 308.

[0068] Venting the chamber 320 allows the extracted liquid to be aspirated into the chamber of the cartridge to which the liquid extraction device 300 is attached (e.g., by a pump in fluid communication with the cartridge chamber, as described with reference to FIG. 1). Alternatively, extraction of liquid from the blood collection tube 11 may be performed when the liquid extraction device 300 is not attached to the cartridge. In this case, the liquid extraction device 300 can then be attached to the cartridge so that the extracted liquid can be aspirated into the cartridge chamber.

[0069] Once the liquid has been extracted from the blood collection tube 11, it can be disconnected from the liquid extraction device 300 by applying an upward force to the blood collection tube 11. This causes the needle 306 to withdraw from the septum 17, causing the septum 17 to reseal.

[0070] 4A-4D show a first liquid extraction device 200 being used to extract liquid from a blood collection tube 11. Fig. 4A shows the liquid extraction device 200 prior to attachment of the blood collection tube 11. The liquid extraction device 200 allows liquid to be extracted from an outlet 216 in a side wall of a cylinder 202 of the liquid extraction device 200.

[0071] Similar to the second liquid extraction device 300 shown in Figures 3A-3D, the liquid extraction device 200 shown in Figures 2A-2D includes an actuatable liquid extraction mechanism in the form of a piston 204 that is actuatable within a cylinder 202 from a first configuration (Figure 2B) to a second configuration (Figure 2D). Figure 2C shows the piston 204 between the first and second configurations.

[0072] The liquid extraction device 200 is fixedly attached to the piston 204 and includes a liquid reservoir interface (e.g., a blood collection tube interface) in the form of a needle 206 having the functionality of needle 306 shown in Figures 3A-3D. The needle 206 includes a liquid extraction outlet 208 through which liquid extracted from the blood collection tube 11 can flow.

[0073] In contrast to the liquid extraction device 300 shown in Figures 3A-3D, the liquid extraction device 200 comprises a first sealing element in the form of a first O-ring seal 210a and a second sealing element in the form of a second O-ring seal 210b. The first O-ring seal 210a extends around the circumference of the piston 204 at a top of the piston 204. The second O-ring seal 210b extends around the circumference of the piston 204 at a bottom of the piston 204. Each O-ring seal 210a, 210b forms a seal between the piston 204 and the cylinder 202.

[0074] 4A-4D, the piston 204 includes a piston section 204a located between O-ring seals 210a, 210b. The cross section of the piston section 204a is smaller than the cross section of the piston section in which the O-ring seals 210a, 210b are attached. The narrower piston section 204a provides a reservoir 224 between the piston 204 and the side wall of the cylinder 202. The reservoir 224 is placed in fluid communication with the liquid extraction outlet 208 upon failure of the second O-ring seal 210b (as described below).

[0075] The cylinder 202 is provided with an opening in the form of a first recess 212a extending around at least a portion of the circumference of an inner side wall of the cylinder 202. The first recess 212a is in fluid communication with a second recess 212b provided in an end wall 218 of the cylinder 202. The second recess 212b extends over a portion of the end wall 218 so as to be in fluid communication with the liquid extraction outlet 208 when the piston 204 is in the second configuration.

[0076] The first recess 212a provides a path for air to flow around the second O-ring seal 210b and into the reservoir 224 when the piston 204 is moved to the second configuration shown in FIGURE 2D. When the piston 204 is in the second configuration, the second O-ring seal 210b is aligned with the first recess 212a, thereby allowing air to escape around the second O-ring seal 210b.

[0077] The recesses 212a, 212b also provide a path for liquid to flow around the second O-ring seal 210b and into the reservoir 224. In particular, when the piston 204 is in the second configuration, the second O-ring seal 210b is aligned with the first recess 212a, allowing air to flow around the second O-ring seal 210b and into the reservoir 224. Liquid can then flow out of the liquid extraction outlet 208 and into the reservoir 224 via the first recess 212a and the second recess 212b.

[0078] An end wall 218 of the cylinder 202 provides a stop to prevent further downward movement of the piston 204. When the piston 204 contacts the end wall 218, the second O-ring seal 210b is aligned with the first recess 212a (as shown in FIG. 4D).

[0079] The cylinder 202 also includes an outlet 216 in a sidewall of the cylinder 202. The outlet 216 is aligned with a reservoir 224 when the piston 204 is in the second configuration (as shown in FIG. 4D).

[0080] The cylinder 202 and the piston 204 together define a chamber 220 between the piston 204 and an end wall 218 of the cylinder 202. The liquid extraction outlet 208 is in fluid communication with the chamber 220. The volume of the chamber 220 decreases as the piston moves from the first configuration to the second configuration. Initially, when the piston 204 is in the first configuration shown in FIG. 4B, the chamber 220 is vented via the outlet 216. Once the piston 204 has passed the outlet 216, the chamber 220 is no longer vented (as shown in FIG. 4C).

[0081] The liquid extraction device 200 shown in Figures 4A-4D extracts liquid from a blood collection tube 11, similar to the liquid extraction device 300 shown in Figures 3A-3D. In particular, as the piston moves from a first configuration to a second configuration, a pressure differential is created between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 208. Specifically, this pressure differential is created as the piston 204 is in the second configuration.

[0082] The blood collection tube 11 is attached to the liquid extraction device 200 in a manner similar to the liquid extraction device 300 shown in Figures 3A-3D. Once the blood collection tube 11 is attached, the volume of the chamber 220 is reduced by applying a downward force. Initially, when the piston 204 is in the position shown in Figure 4B, the downward movement of the piston 204 displaces air from the chamber 220 and expels it through the outlet 216 (e.g., to a vent cartridge). However, as the piston 204 moves past the outlet 216, the volume of the chamber 220 is reduced and the air in the chamber 220 is pressurized, thereby forcing the air through the needle 206 and into the blood collection tube 11 (Figure 4C). This increases the pressure of the volume 21 of gas in the blood collection tube 11.

[0083] As a result of the piston 204 moving further downwards, the pressure in the gas volume 21 increases further until the piston 204 reaches the second configuration (FIG. 4D). In the second configuration, the second O-ring seal 210b is aligned with the first recess 212a. This allows air from the chamber 220 (now having a very small volume) to escape through the first recess 212a, around the second O-ring seal 210b, and through the outlet 216. At this point, the chamber 220 and the liquid extraction outlet 208 are at atmospheric pressure, while the gas volume 21 is above atmospheric pressure. This pressure difference forces liquid through the needle 206, through the liquid extraction outlet 208 and the recesses 212a, 212b, and into the reservoir 224.

[0084] When the blood collection tube 11 is disconnected from the liquid extraction device 200, the reservoir 224 is vented via the needle 206. The extracted liquid can then be aspirated from the reservoir 224 into the chamber of the cartridge.

[0085] 5A-5D show a third liquid extraction device 400 being used to extract liquid from a blood collection tube 11. Fig. 5A shows the liquid extraction device 400 before attachment of the blood collection tube 11. The liquid extraction device 400 allows liquid to be extracted by generating a negative pressure in a chamber 420 of the liquid extraction device 400.

[0086] The liquid extraction device 400 includes a cylinder 402 (or tube) in which a blood collection tube 11 is received. The liquid extraction device 400 also includes an actuatable liquid extraction mechanism in the form of a piston 404 and a liquid reservoir interface (e.g., blood collection tube interface) in the form of a needle 406 having a liquid extraction outlet 408, each having the same function as the piston 304 and needle 306 of the liquid extraction device 300 shown in Figures 3A-3D. However, in contrast to the piston 304 of the liquid extraction device 300 shown in Figures 3A-3D, the piston 404 shown in Figures 5A-5D includes a sealing element in the form of an O-ring seal 410 that extends around the circumference of the piston 404 at the top of the piston 404.

[0087] Similar to the liquid extraction device 300 shown in Figures 3A-3D, the cylinder 404 of the liquid extraction device 400 shown in Figures 5A-5D includes an outlet 416 disposed in an end wall 418 of the cylinder 402. The outlet 416 is in fluid communication with a connector 422. Additionally, the cylinder 402 includes a recess 412 extending around at least a portion of the circumference of an interior sidewall of the cylinder 412. The recess 412 provides a path for air flow around the O-ring seal 410 when the O-ring seal 410 is aligned with the recess 412.

[0088] The cylinder 402 also includes a stopper 414 in the form of a protrusion extending from an interior sidewall of the cylinder 402. The stopper 414 extends around at least a portion of the circumference of the inner wall of the cylinder 402 and prevents upward movement of the piston 404 within the cylinder 402 beyond the point at which the stopper 414 protrudes. The stopper 414 is disposed to align the O-ring seal 410 of the piston 404 with the recess 412 when the piston 404 abuts the stopper 414.

[0089] The piston 404 and cylinder 402 together define a non-vented chamber 420 (as best shown in FIG. 5C) between the piston 404 and an end wall 418 of the cylinder 402. In contrast to the chamber 320 of the liquid extraction device 300 shown in FIGS. 3A-3D, the volume of the chamber 420 shown in FIGS. 5A-5D increases as the piston 404 is moved outwardly from the end wall 418 of the cylinder 402. A stopper 414 defines a maximum volume of the chamber 420.

[0090] The procedure for extracting liquid from the blood collection tube 11 is illustrated in Figures 5A-5D. As with the embodiment described above, liquid is extracted by creating a pressure differential between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 408 as the piston 404 moves from the first configuration to the second configuration. In the embodiment illustrated in Figures 5A-5D, the pressure differential is created during actuation of the piston 404 from the first configuration to the second configuration.

[0091] The blood collection tube 11 is attached to the liquid extraction device 400 in a manner similar to the embodiment described above. When attached as shown in FIG. 4B (i.e., with the piston 404 in the first configuration), there is no pressure difference between the volume of gas 21 and the liquid extraction outlet 408.

[0092] When the user applies an upward force to the blood collection tube 11, the piston 404 is displaced within the cylinder 402, increasing the volume of the chamber 420, as shown in FIG. 5C. Given that the chamber 420 is not vented, the increase in the volume of the chamber 420 reduces the pressure of the air in the chamber 420 to below atmospheric pressure, as the O-ring seal 410 prevents air from escaping the chamber 420. This means that there is a pressure difference between the volume of gas 21 in the blood collection tube 11 (which is at atmospheric pressure) and the liquid extraction outlet 408 into the chamber 420 (which is below atmospheric pressure). This pressure difference pushes liquid through the needle 406 and into the chamber 420 via the liquid extraction outlet 408.

[0093] As a result of the piston 404 moving further upwards by continuing to apply an upward force, the pressure of the air in the chamber 420 and the blood collection tube 11 is further reduced, thereby drawing more liquid from the blood collection tube 11. This continues until the piston 404 reaches the second configuration shown in FIG. 5D. When the piston 404 is in the second configuration, the O-ring seal 410 is aligned with the recess 412 and is consequently broken, allowing air to escape around the O-ring seal 410 via the recess 412. This means that the chamber 420 is vented to the atmosphere, thereby equalizing the pressure between the chamber 420 and the volume of gas 21 in the blood collection tube 11. The equalization of the pressure between the chamber 420 (and the liquid extraction outlet 408) and the volume of gas 21 stops the flow of liquid into the chamber 420. The venting of the chamber 420 allows liquid to be aspirated into the chamber of the cartridge. The blood collection tube 11 can then be disconnected from the liquid extraction device 400.

[0094] 6A-6D show a fourth liquid extraction device 500 being used to extract liquid from a blood collection tube 11. Fig. 6A shows the liquid extraction device 500 before attachment of the blood collection tube 11. The liquid extraction device 500 creates a pressure differential between a piston 504 and a chamber 520 provided between a side wall of a cylinder 502.

[0095] Similar to the previously described embodiments, the liquid extraction device 500 includes an actuatable liquid extraction mechanism (piston 504) movable within a cylinder 502 from a first configuration (FIG. 6B) to a second configuration (FIG. 6D).

[0096] 6A-6D, a cylinder 502 has a first cylindrical portion 502a having a first cross-section, a second cylindrical portion 502b having a second cross-section smaller than the first cross-section, and a tapered portion 502c (shown in FIG. 6C) between the first cylindrical portion 502a and the second cylindrical portion 502b. At the tapered portion 502c, the cross-section of the cylinder 502 decreases from the first cross-section to the second cross-section.

[0097] Similarly, the piston 504 comprises a first cylindrical piston portion 504a having a first cross-section, a second cylindrical piston portion 504b having a second cross-section smaller than the first cross-section, and a tapered piston portion 504c between the first cylindrical piston portion 504a and the second cylindrical piston portion 504b (shown in FIG. 6C). At the tapered piston portion 504c, the cross-section of the piston 504 decreases from the first cross-section to the second cross-section. The cross-section of the first cylindrical piston portion 504a is between the cross-sections of the first cylindrical portion 502a and the second cylindrical portion 502b. The cross-section of the second cylindrical piston portion 504b is smaller than the cross-section of the second cylindrical portion 502b such that the second cylindrical piston portion 504b is movable within the second cylindrical portion 502b.

[0098] Similar to the implementations described above, the liquid extraction device 500 includes a liquid reservoir interface (e.g., a blood collection tube interface) in the form of a needle 506 having a liquid extraction outlet 508. In the example shown in Figures 6A-6D, the liquid extraction outlet 508 is provided in a side wall of the piston 504 (specifically, in a side wall of the second cylindrical piston portion 504b). As a result, the piston 504 includes an L-shaped channel 524 (shown in Figure 6C) that connects the end of the needle 506 protruding from the piston 504 and the liquid extraction outlet 508.

[0099] The piston 504 also includes sealing elements in the form of a first O-ring seal 510a extending around the piston 504 at a top of the piston 504 (specifically around a top of the first cylindrical piston portion 504a) and a second O-ring seal 510b extending around the piston 504 at a bottom of the piston 504 (specifically around a bottom of the second cylindrical piston portion 504b). The O-ring seals 510a, 510b form a seal between the piston 504 and the cylinder 502, which prevents air from escaping from within the cylinder 502 when the piston 504 is in the position shown in Figures 6A-6C. Specifically, the first O-ring seal 510a forms a seal between the first cylindrical piston portion 504a and the first cylinder portion 502a, and the second O-ring seal 510b forms a seal between the second cylindrical piston portion 504b and the second cylindrical portion 502b.

[0100] The cylinder 502 also includes an outlet 516 that allows liquid to be removed from the liquid extraction device 500 upon its extraction from the blood collection tube 11. In the example shown in Figures 6A-6D, the outlet 516 is located in a side wall of the cylinder 502 (specifically, in a side wall of the second cylindrical portion 502b). The outlet 516 also acts as an opening to break the seal provided by the second O-ring seal 510b.

[0101] The cylinder 502 and the piston 504 together define a non-vented chamber 520 between the piston 504 and the interior sidewall of the cylinder 502. When the piston 504 is in the position shown in Figure 6C, the O-ring seals 510a, 510b prevent air from escaping the chamber 520. The volume of the chamber 520 decreases as the piston 504 moves toward the end wall 518 of the cylinder 502 (i.e., as the piston 504 moves from the first configuration to the second configuration).

[0102] An end wall 518 is provided at the end of the second cylinder portion 502b. The end wall 518 defines a stop that provides a range of movement for the piston 504. When the piston 504 abuts the end wall 518, the liquid extraction outlet 508 is aligned with an outlet 516 in the cylinder 502. As the piston 504 displaces downward (i.e., as the piston 504 moves from the position shown in FIG. 6B to the position shown in FIG. 6C), any air in the area between the end wall 518 and the bottom of the piston 504 escapes through the outlet 516.

[0103] The procedure for extracting liquid from the blood collection tube 11 is similar to that of the liquid extraction devices 200, 300 described above and is illustrated in Figures 6A-6D. That is, as the piston 504 moves from the first configuration to the second configuration, a pressure differential is created between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 508. Specifically, in the example illustrated in Figures 6A-6D, a pressure differential is created as the piston 504 moves to the second configuration.

[0104] The blood collection tube 11 is attached to the liquid extraction device 500 in a manner similar to the embodiment described above. Upon attachment, when a user applies a downward force to the blood collection tube 11, the piston 504 is displaced within the cylinder 502, decreasing the volume of the chamber 520, as shown in FIG. 5C. The decrease in the volume of the chamber 520 pressurizes the chamber 520, forcing air into the blood collection tube 11 through the needle 506 via the L-shaped channel 524 (FIG. 6C). This increases the pressure of the volume of gas 21 within the blood collection tube 11.

[0105] As a result of the piston 504 moving further downward, the pressure of the volume of gas 21 increases further until the piston 504 reaches the second configuration shown in FIG. 6D. When the piston 504 is in the second configuration, the liquid extraction outlet 508 is aligned with the outlet 516, which acts as an opening that breaks the seal of the chamber 520 provided by the second O-ring seal 510b, thereby allowing any air remaining in the chamber 520 to escape through the outlet 516. At this point, the pressure of the volume of gas 21 in the blood collection tube 11 is higher than the pressure at the liquid extraction outlet 508 (which is at atmospheric pressure). This pressure difference pushes liquid out of the liquid extraction device 500 through the needle 506 via the L-shaped channel 524 and the liquid extraction outlet 508. For example, liquid may be pushed into the chamber of the cartridge through the liquid extraction outlet 508. The blood collection tube 11 can then be disconnected from the liquid extraction device 500.

[0106] 7A-7D show a fifth liquid extraction device 600 being used to extract liquid from a blood collection tube 11. Fig. 7A shows the liquid extraction device 600 prior to attachment of a blood collection tube 11. The liquid extraction device 600 includes a separate vent chamber through which extracted liquid can be aspirated.

[0107] Similar to the above embodiment, the liquid extraction device 600 includes a cylinder 602 (or tube) in which the blood collection tube 11 is received. The liquid extraction device 600 also includes an actuatable liquid extraction mechanism in the form of a piston 604 and a liquid reservoir interface (e.g., blood collection tube interface) in the form of a needle 606 having a liquid extraction outlet 608.

[0108] The cylinder 602 includes a partition 626 that extends across a cross section of the cylinder 602. The partition 626 defines a separate chamber 628 within the cylinder 602. Specifically, the chamber 628 is defined between an end wall 618 of the cylinder 602 and the partition 626. Similar to the implementations above, the cylinder 602 includes an outlet 616 that allows liquid to be removed from the liquid extraction device 600. The outlet 616 is provided in a side wall of the cylinder 602 and is in fluid communication with the chamber 628. The outlet 616 can be vented (e.g., by connection to a vent cartridge), meaning that the chamber 628 is at atmospheric pressure.

[0109] Septum 626 further includes a sealed opening 630 (e.g., in the center of septum 626). Sealed opening 630 is puncturable such that opening 630 provides a fluid connection into chamber 628 when punctured.

[0110] Piston 604 comprises a support 632 attached to a deformable element in the form of a non-vented bellows chamber 620. Bellows chamber 620 is disposed between support 632 and a bulkhead 626. Bellows chamber 620 has bellows-shaped sides that allow the volume of bellows chamber 620 to be reduced from a first volume shown in FIG. 7B (i.e., when piston 604 is in a first configuration) to a reduced volume shown in FIG. 7D (i.e., when piston 604 is in a second configuration).

[0111] Needle 606 is mounted within support 632. Liquid extraction outlet 608 extends partially into bellows chamber 620 and is configured to pierce a sealed opening 630 in septum 626 when piston 604 is actuated to the second configuration. Needle 606 and liquid extraction outlet 608 may be provided, for example, in the form of a double-ended needle extending through support 632.

[0112] The procedure for extracting liquid from the blood collection tube 11 is illustrated in Figures 7A-7D. As with the embodiment described above, liquid is extracted by creating a pressure differential between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 608 as the piston 604 moves from the first configuration to the second configuration. In the embodiment illustrated in Figures 7A-7D, a pressure differential is created as the piston 604 is in the second configuration.

[0113] The blood collection tube 11 is attached to the liquid extraction device 600 in a manner similar to the embodiment described above. When attached as shown in FIG. 4B (i.e., with the piston 604 in the first configuration), there is no pressure difference between the volume of gas 21 and the liquid extraction outlet 608.

[0114] As a result of piston 604 moving downward, the volume of bellows chamber 620 decreases. Because bellows chamber 620 is not vented, the decrease in volume increases the air pressure within bellows chamber 620, forcing air through needle 606 and into blood collection tube 11. This increases the pressure of volume 21 of gas within blood collection tube 11.

[0115] As a result of the piston 604 moving further downwards, the pressure in the volume of gas 21 increases further until the piston 604 reaches the second configuration (FIG. 7D). In the second configuration, the liquid extraction outlet 608 pierces the sealed opening 630, placing the liquid extraction outlet 608 in fluid communication with the chamber 628, which is at atmospheric pressure. Thus, there is a pressure difference between the liquid extraction outlet 608 (which is at atmospheric pressure) and the volume of gas 21. This pressure difference forces liquid through the needle 606, via the liquid extraction outlet 608, and into the chamber 628.

[0116] When the blood collection tube 11 is disconnected from the liquid extraction device 600, the chamber 628 is vented via the opening 630 and the needle 606. The extracted liquid can then be aspirated from the chamber 628 of the liquid extraction device 600 into the chamber of the cartridge.

[0117] 8A-8D show a sixth liquid extraction device 700 being used to extract liquid from a blood collection tube 11. FIG. 8A shows the liquid extraction device 700 before the blood collection tube 11 is attached. The liquid extraction device 700 is used to pressurize the volume of gas 21 in the blood collection tube 11 and then generate a pressure difference between the volume of gas 21 and the liquid extraction outlet 708. The liquid extraction device 700 includes an elastically deformable element that slows down the rate of change of pressure when generating a pressure difference (when compared to the pressure difference generated using the liquid extraction devices 200, 300, 500). Using a slower rate of pressure change can reduce hemolysis that can occur during rapid blood flow when pressure changes are generated instantaneously. The elastically deformable element also allows for a controlled change of pressure because the rate of change of pressure is dictated by the elastically deformable element and not by the user applying an upward force on a piston (as with the liquid extraction device 400).

[0118] The liquid extraction device 700 comprises an actuatable liquid extraction mechanism in the form of a piston 704 movable from a first configuration (FIG. 8B) to a second configuration (FIG. 8D) within a cylinder 702. The liquid extraction device 700 also includes a liquid reservoir interface (e.g., a blood collection tube interface) in the form of a needle 706 having a liquid extraction outlet 708. The piston 704 comprises a sealing element in the form of an O-ring seal 710 that extends around the circumference of the piston 704 at an upper portion of the piston 704. The O-ring seal 710 provides a seal between the cylinder 702 and the piston 704.

[0119] The cylinder 702 also includes an outlet 716 that allows liquid extracted from the blood collection tube 11 to be removed from the liquid extraction device 700. The outlet 716 is provided in a side wall of the cylinder 702.

[0120] The piston 704 and the cylinder 702 together define a chamber 720. In particular, the chamber 720 is defined within the cylinder 702 between an end wall 718 of the cylinder 702 and the piston 704. The liquid extraction device 700 further includes a resiliently deformable element (shown in the form of a spring 734 in FIGS. 8A-8D ) disposed within the chamber 720. When compressed, the spring 734 biases the piston 704 outwardly from the end wall 718 of the cylinder 702.

[0121] The chamber 720 is vented when the blood collection tube 11 is initially attached to the liquid extraction device 700 (i.e., when the piston 704 is in the position shown in FIG. 8A) and when the spring 734 returns the piston 704 to its starting position (i.e., the second configuration shown in FIG. 8D). Once the piston 704 is actuated past the outlet 716 in the side wall of the cylinder 702, the chamber 720 is no longer vented (i.e., in the position shown in FIGS. 8B and 8C).

[0122] The procedure for extracting liquid from the blood collection tube 11 is illustrated in Figures 8A-8D. As with the embodiment described above, liquid is extracted by creating a pressure differential between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 708 as the piston 704 moves from a first configuration (Figure 8B) to a second configuration (Figure 8D). In the embodiment illustrated in Figures 8B-8D, the pressure differential is created during actuation of the piston 704 from the first configuration to the second configuration.

[0123] The blood collection tube 11 is attached to the liquid extraction device 700 in a manner similar to the embodiment described above. When attached, there is no pressure difference between the volume of gas 21 and the liquid extraction outlet 708.

[0124] As a downward force is applied to the blood collection tube 11, the piston 704 is displaced downward within the cylinder 702, past the outlet 716. Further downward movement decreases the volume of the chamber 720, thereby increasing the pressure of the air within the chamber 720. This forces air into the blood collection tube 11 through the needle 706, increasing the pressure of the gas volume 21 within the blood collection tube 11. The downward movement of the piston 704 also compresses the spring 734. At the end of the stroke (FIG. 8B), the piston 704 is in the first configuration, and the pressure of the air within the chamber 720 and within the blood collection tube 11 has increased, but there is no pressure difference.

[0125] As a result of the release of the downward force applied to the blood collection tube 11, an upward force is applied by the spring 734 to the piston 704. The upward force applied by the spring 734 increases the volume of the chamber 720, thereby decreasing the air pressure in the chamber 720. This creates a pressure differential between the liquid extraction outlet 708 and the volume of gas 21, forcing liquid through the needle 706 and into the chamber 720 (as shown in FIG. 8C). The spring 734 continues to apply an upward force to the piston 704 (thereby providing a pressure differential that results in the extraction of liquid) until the piston 704 returns to the second configuration (its starting position) shown in FIG. 8D.

[0126] When the blood collection tube 11 is disconnected from the liquid extraction device 700, the chamber 720 is vented via the needle 706. The extracted liquid can then be aspirated from the chamber 720 of the liquid extraction device 700 via the outlet 716 into the chamber of the cartridge.

[0127] 9A-9D show a seventh liquid extraction device 800 being used to extract liquid from a blood collection tube 11. FIG. 9A shows the liquid extraction device 800 prior to attachment of a blood collection tube 11. The liquid extraction device 800 can be used to extract liquid from a blood collection tube 11 similar to the liquid extraction device 700 shown in FIGS. 8A-8D, but includes an elastically deformable bellows chamber 820 in place of the spring 734 used in the liquid extraction device 700.

[0128] The liquid extraction device 800 comprises an actuatable liquid extraction mechanism in the form of a piston 804 movable within a cylinder 802 from a first configuration (FIG. 9B) to a second configuration (FIG. 9D). Similar to the liquid extraction device 600 shown in FIGS. 7A-7D, the piston 804 comprises a support 832 and a non-vented compressible bellows chamber 820 disposed between the support 832 and an end wall 818 of the cylinder 802. The bellows chamber 820 has bellows-shaped sides that allow the volume of the bellows chamber 820 to be reduced from a first volume shown in FIGS. 9A and 9D (i.e., when the piston 804 is in the second configuration) to a reduced volume shown in FIG. 9B (i.e., when the piston 804 is in the first configuration).

[0129] The liquid extraction device 800 also includes a liquid reservoir interface (eg, a blood collection tube interface) in the form of a needle 806 having a liquid extraction outlet 808. The liquid extraction outlet 808 is in fluid communication with a bellows chamber 820.

[0130] The cylinder 802 includes an outlet 816 that allows liquid extracted from the blood collection tube 11 to be removed from the liquid extraction device 800. The outlet 816 is in fluid communication with a connector 822 that provides attachment of the liquid extraction device 800 to a cartridge. The connector 822 is closed (not vented) during extraction of liquid from the blood collection tube 11 and only opens when the liquid extraction device 800 is attached to the cartridge.

[0131] The procedure for extracting liquid from the blood collection tube 11 is illustrated in Figures 9A-9D. As with the embodiment described above, liquid is extracted by creating a pressure differential between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 808 as the piston 804 moves from a first configuration (Figure 9B) to a second configuration (Figure 9D). In the embodiment illustrated in Figures 9B-9D, the pressure differential is created during actuation of the piston 804 from the first configuration to the second configuration.

[0132] The procedure for extracting liquid is the same as that of the liquid extraction device 700 shown in Figures 8A-8D. Finally, the blood collection tube 11 is first attached. A downward force is then applied, decreasing the volume of the bellows chamber 820, thereby increasing the air pressure in the bellows chamber 820 and in the blood collection tube 11 (Figure 9B). The downward force is then released, resulting in an upward force being applied to the piston 804 by the elastically deformable bellows chamber 820 (Figure 9C). This increases the volume of the bellows chamber 820, decreasing the air pressure in the bellows chamber 820, thereby creating a pressure differential that draws liquid from the blood collection tube 11 through the needle until the piston 804 returns to the second configuration (Figure 9D).

[0133] When the blood collection tube 11 is disconnected from the liquid extraction device 800, the bellows chamber 820 is vented via the needle 806. The extracted liquid can then be drawn from the chamber 820 of the liquid extraction device 800 via the outlet 816 into the chamber of the cartridge.

[0134] 10A-10D show an eighth liquid extraction device 900 being used to extract liquid from a blood collection tube 11. FIG. 10A shows the liquid extraction device 900 before the blood collection tube 11 is attached. The liquid extraction device 900 is used to extract liquid from a blood collection tube 11 using an elastically deformable element to generate a negative pressure in the chamber 920 (similar to the liquid extraction devices 700, 800 shown in FIGS. 8A-8D and 9A-9D). However, in contrast to the liquid extraction devices 700, 800, the liquid extraction device 900 includes a mechanism for releasing the elastically deformable element from a compressed state in order to apply an upward force to the piston 904. This eliminates the need for a downward force to be applied by the user to compress the elastically deformable element.

[0135] The liquid extraction device 900 comprises an actuatable liquid extraction mechanism in the form of a piston 904 movable from a first configuration (FIG. 10B) to a second configuration (FIG. 10D) within a cylinder 902. The liquid extraction device 900 also includes a liquid reservoir interface (e.g., a blood collection tube interface) in the form of a needle 906 having a liquid extraction outlet 908.

[0136] 10A-10D, a cylinder 902 includes a first cylindrical portion 902a having a first cross-section and a second cylindrical portion 902b having a second cross-section that is smaller than the first cross-section. An annular wall 902c joins the first cylindrical portion 902a to the second cylindrical portion 902b.

[0137] Similarly, the piston 904 comprises a first cylindrical piston portion 904a having a first cross section, a second cylindrical piston portion 904b having a second cross section smaller than the first cross section, and an annular surface 904c joining the first cylindrical piston portion 904a to the second cylindrical piston portion 904b. The cross section of the first cylindrical piston portion 904a is between the cross sections of the first cylindrical portion 902a and the second cylindrical portion 902b. The cross section of the second cylindrical piston portion 904b is smaller than the cross section of the second cylindrical portion 902b such that the second cylindrical piston portion 902b is movable within the second cylindrical portion 904b. A liquid extraction outlet 908 is provided at the bottom of the second cylindrical piston portion 904b.

[0138] The liquid extraction device 900 also includes an elastically deformable element in the form of a spring 934. The spring 934 is attached to the annular wall 902c of the cylinder 902 and to the annular surface 904c of the piston 904. When compressed, the spring 934 urges the annular surface 904c of the piston 904 outwardly from the annular wall 902c of the cylinder 902.

[0139] The piston 904 further includes a sealing element in the form of an O-ring seal 910 that extends around the circumference of the piston 904 at the bottom of the piston 904. Specifically, the O-ring seal 910 extends around the circumference of the second cylindrical piston portion 904b at the bottom of the second cylindrical piston portion 904b.

[0140] The cylinder 902 also includes an outlet 916 that allows liquid extracted from the blood collection tube 11 to be removed from the liquid extraction device 900. The outlet 916 is provided in a side wall of the cylinder 902. Specifically, the outlet 916 is provided in a side wall of the second cylindrical portion 902b.

[0141] The piston 904 (specifically, the second cylindrical piston portion 904b) and the cylinder 902 (specifically, the second cylindrical portion 902b) together define a chamber 920. In particular, the chamber 920 is defined between the second cylindrical piston portion 904b and an end wall 918 at the end of the second cylindrical portion 902b. The chamber 920 is vented when the O-ring seal 910 is actuated past the outlet 916 by application of an upward force from a spring 934 to the annular surface 902c.

[0142] The cylinder 902 further includes a resiliently deformable clip 936 that extends inwardly from an inner wall of the first cylinder portion 902a. The clip 936 hinges from the inner wall of the first cylinder portion 902a. The clip 936 extends far enough from the inner wall to hold the piston 904 in the position shown in FIG. 10A. In this position, the spring 934 is compressed and the piston 904 is held in place by the resiliently deformable clip 936. In particular, the spring 934 exerts an upward force that presses the first cylindrical piston portion 904a against the clip 936.

[0143] The elastically deformable clip 936 is dimensioned such that it can be pushed toward the inner wall of the first cylinder portion 902a by the rim of the cap 15 of the blood collection tube 11. When the clip 936 is displaced by the cap 15 toward the inner wall of the first cylinder portion 902a, the piston 904 is unclipped and is free to move upwards within the cylinder 902 (due to the upward force exerted by the spring 934).

[0144] A procedure for extracting liquid from a blood collection tube 11 is shown in Figures 10A-10D. As with the embodiment described above, liquid is extracted by creating a pressure differential between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 908 as the piston 904 moves from a first configuration (Figure 10B) to a second configuration (Figure 10D). In the embodiment shown in Figures 10B-10D, the pressure differential is created during actuation of the piston 904 from the first configuration to the second configuration.

[0145] Initially, the piston 904 is held in place in a first configuration by the elastically deformable clip 936. The blood collection tube 11 is attached to the liquid extraction device 900 by applying a downward force to the blood collection tube 11 such that the needle 906 pierces the septum 17. When the needle 906 is fully inserted through the septum 17, the cap 15 pushes the clip 936 outward toward the inner wall of the cylinder 902. This unclipping and releasing the piston 904, as shown in FIG. 10B. At this point, there is no pressure difference between the liquid extraction outlet 908 and the volume of gas 21.

[0146] As a result of the release of the piston 904 from the clip 936, an upward force is exerted on the piston 904 by the spring 934. The upward force exerted by the spring 934 increases the volume of the chamber 920, thereby decreasing the air pressure in the chamber 920. This creates a pressure differential between the liquid extraction outlet 908 and the volume of gas 21, forcing liquid through the needle 906 and into the chamber 920 (FIG. 10C). The spring 934 continues to exert an upward force on the piston 904 (thereby providing a pressure differential that results in the extraction of liquid) until the piston 904 reaches the second configuration (FIG. 10D).

[0147] When the blood collection tube 11 is disconnected from the liquid extraction device 900, the chamber 920 is vented via the needle 906. The extracted liquid can then be aspirated from the chamber 920 of the liquid extraction device 900 via the outlet 916 into the chamber of the cartridge.

[0148] 11A-11D show a ninth liquid extraction device 1000 being used to extract liquid from a blood collection tube 11. FIG 11A shows the liquid extraction device 1000 before attachment of a blood collection tube 11. The liquid extraction device 1000 extracts liquid similarly to the liquid extraction device 300 shown in FIGS. 3A-3D, but uses a piston 1004 that is actuated from a first configuration to a second configuration using an elastically deformable element rather than by application of force by a user.

[0149] Similar to the liquid extraction device 300 shown in Figures 3A-3D, the liquid extraction device 1000 shown in Figures 11A-11D includes an actuatable liquid extraction mechanism in the form of a piston 1004 movable within a cylinder 1002 from a first configuration to a second configuration. The liquid extraction device 1000 also includes a liquid reservoir interface (e.g., a blood collection tube interface) in the form of a needle 1006 having a liquid extraction outlet 1008.

[0150] The piston 1004 includes a sealing element in the form of an O-ring seal 1010 that extends around the circumference of the piston 1004 at the bottom of the piston 1004. The cylinder 1002 includes an opening in the form of a recess 1012 that extends around at least a portion of the circumference of an interior sidewall of the cylinder 1002. The recess 1012 provides a path for air to flow around the O-ring seal 1010 when the piston 1004 is in the second configuration, thereby compromising the O-ring seal 1010.

[0151] The cylinder 1002 also includes a stopper 1014 that protrudes from an inner sidewall of the cylinder 1002 and extends around at least a portion of the circumference of the inner wall to prevent downward movement of the piston 1004 within the cylinder 1002 beyond the point at which the stopper 1014 protrudes. The stopper 1014 is positioned to align an O-ring seal 1010 of the piston 1004 with a recess 1012 in the cylinder 1002 when the piston 1004 abuts the stopper 1014.

[0152] The cylinder 1002 also includes an outlet 1016 that allows liquid extracted from the blood collection tube 11 to be removed from the liquid extraction device 1000. The outlet 1016 is provided in an end wall 1018 of the cylinder 1002 and is in fluid communication with a connector 1022 that allows the liquid extraction device 1000 to be attached to a cartridge. The connector 1022 seals the chamber 1020 until the liquid extraction device 1000 is attached to a cartridge.

[0153] The piston 1004 and the cylinder 1002 together define a non-vented chamber 1020. Specifically, the chamber 1020 is defined between an end wall 1018 of the cylinder 1002 and the piston 1004. A liquid extraction outlet 1008 is in fluid communication with the chamber 1020.

[0154] In contrast to the liquid extraction device 300 shown in Figures 3A-3D, the liquid extraction device 1000 further comprises a support 1032 located within the cylinder 1002. The support 1032 extends across at least a portion of the cross section of the cylinder 1002, and may for example extend from an interior side wall of the cylinder 1002. The needle 1006 is fixedly mounted within the support 1020 and extends through it.

[0155] The piston 1004 is disposed below the support 1020. The piston 1004 comprises a central cylindrical portion 1004a with a central bore through which the needle 1006 is disposed. The central bore of the central cylindrical portion 1004a allows the piston 1004 to be slidably movable relative to the needle 1006. The central cylindrical portion 1004a is joined to an end 1004b to which an O-ring seal 1010 is attached. The central bore also extends through the end 1004b of the piston 1004. The piston 1004 also comprises elastically deformable clips 1004c extending upward from the end 1004. The clips 1004c are received in corresponding openings 1030 in the support 1020. The clips 1004c maintain the piston 1004 in the first configuration (FIG. 11B) until they are disengaged from the openings 1030. Clip 1004c and opening 1030 are dimensioned such that clip 1004c can be deformed out of engagement with opening 1030 by abutting cap 15 of blood collection tube 11 against clip 1004c.

[0156] The liquid extraction device further comprises a spring 1034 disposed between the end 1004b of the piston 1004 and the underside of the support 1020. When compressed, the spring 1034 urges the end 1004b of the piston 1004 outwardly from the support 1020.

[0157] The procedure for extracting liquid from the blood collection tube 11 is shown in Figures 11A-11D. As with the embodiment described above, liquid is extracted by creating a pressure differential between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 1008 as the piston 1004 moves from a first configuration (Figure 11B) to a second configuration (Figure 11D). In the embodiment shown in Figures 11B-11D, a pressure differential is created as the piston 1004 moves to the second configuration.

[0158] Initially, the piston 1004 is held in place in the first configuration by the elastically deformable clip 1004c. The blood collection tube 11 is attached to the liquid extraction device 1000 by applying a downward force to the blood collection tube 11 such that the needle 1006 pierces the septum 17. When the needle 1006 is fully inserted through the septum 17, the cap 15 pushes the clips 1004c outward, thereby pushing them out of engagement with the openings 1030 in the support 1020. This unclipping and releasing the piston 1004. Initially, there is no pressure difference between the liquid extraction outlet 1008 and the volume of gas 21.

[0159] As a result of the piston 1004 being released from the clip 1004c, a downward force is applied to the piston 1004 by the spring 1034. The downward force applied by the spring 1034 pushes the piston 1004 downward (outward from the support 1020), decreasing the volume of the chamber 1020, thereby increasing the air pressure in the chamber 1020 (as shown in FIG. 11C). The increasing air pressure in the chamber 1020 forces air through the needle 1006, thus increasing the air pressure in the blood collection tube 11. At this point, there is no pressure difference between the liquid extraction outlet 1008 (in the chamber 1020) and the volume of gas 21 in the blood collection tube 11.

[0160] Further downward movement of the piston 1004 by the spring 1034 results in a further increase in pressure in the volume of gas 21 until the piston 1004 reaches the second configuration (FIG. 11D). In the second configuration, the O-ring seal 1010 is aligned with the recess 1012. This allows air from the chamber 1020 to escape around the O-ring seal 1020 via the recess 1012. At this point, the chamber 1020 and the liquid extraction outlet 1008 are at atmospheric pressure, while the volume of gas 21 is above atmospheric pressure. This pressure difference forces liquid through the needle 1006 and into the chamber 1020 via the liquid extraction outlet 1008.

[0161] Once the chamber 1020 is vented, the extracted liquid can be aspirated from the chamber 1020 into the chamber of the cartridge. The blood collection tube 11 can then be connected or disconnected from the liquid extraction device 1000.

[0162] 12A-12D show a tenth liquid extraction device 1100 being used to extract liquid from a blood collection tube 11. FIG. 12A shows the liquid extraction device 1100 prior to attachment of the blood collection tube 11. The liquid extraction device 1100 uses a static attachment of the blood collection tube 11 to the needle 1106, and an actuatable liquid extraction mechanism is provided external to the cylinder 1102. Specifically, the liquid extraction mechanism is provided in the form of a plunger 1138.

[0163] Similar to the implementations described above, the liquid extraction device 1100 includes a cylinder 1102 into which a blood collection tube 11 is received. The liquid extraction device 1100 also includes a liquid reservoir interface (e.g., blood collection tube interface) in the form of a needle 1106. The needle 1106 is fixedly attached to an end wall 1118 of the cylinder 1102. When the blood collection tube 11 is attached to the liquid extraction device 1100, the cap 15 abuts the end wall 1118.

[0164] The needle 1106 comprises a liquid extraction outlet 1108. In the example shown in Figures 12A-12D, the liquid extraction outlet 1108 is the same as the outlet from the cylinder 1102. The liquid extraction device 1100 also comprises a connector 1122 that allows the liquid extraction device 1100 to be attached to a cartridge.

[0165] The liquid extraction device 1100 also includes an actuatable liquid extraction mechanism in the form of a plunger 1138 that is movable within a housing 1140 from a first configuration (FIGS. 12A and 12B) to a second configuration (FIGS. 12C and 12D). The interface between the plunger 1138 and the housing 1140 is sealed (e.g., using an O-ring or similar sealing element, not shown in FIGS. 12A-12D) so that air does not escape from the housing 1140 around the sides of the plunger 1138.

[0166] 12A-12D, the housing 1140 may be attached to a side wall of the cylinder 1102. The liquid extraction mechanism also includes an air transfer conduit 1142 in fluid communication with the housing 1140 and the liquid extraction outlet 1108. When the plunger 1138 is actuated from the first configuration to the second configuration, air is forced out of the housing 1140, through the air transfer conduit 1142 and to the liquid extraction outlet 1108.

[0167] The procedure for extracting liquid from the blood collection tube 11 is illustrated in Figures 12A-12D. When the plunger 1138 moves from a first configuration (Figure 12B) to a second configuration (Figure 12D), liquid is extracted by creating a pressure differential between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 1108. In the embodiment illustrated in Figures 12A-12D, a pressure differential is created when the plunger 1138 is in the second configuration.

[0168] The blood collection tube 11 is attached to the liquid extraction device 1100 by applying a downward force to the blood collection tube 11 such that the needle 1106 pierces the septum 17. The blood collection tube 11 is fully attached when the cap 15 abuts the end wall 1118 of the cylinder 1102.

[0169] Initially, the plunger 1138 is in a first configuration (FIG. 12B). The plunger 1138 is actuated to a second configuration by applying a downward force to the plunger 1138 to push the plunger 1138 into the housing 1140. Pushing the plunger 1138 into the housing 1140 displaces air within the housing 1140 into the air transfer conduit 1142 (FIG. 12C). Because the air transfer conduit 1142 is in fluid communication with the liquid extraction outlet 1108, air is forced into the blood collection tube 11 through the liquid extraction outlet 1108 and the needle 1106. This causes the pressure of the air within the blood collection tube 11 to increase.

[0170] When the liquid extraction outlet 1108 is vented, a pressure difference is created between the liquid extraction outlet 1108 and the volume of gas 21. The liquid extraction outlet 1108 may be vented in different ways. As a first example, the liquid extraction outlet 1108 may be connected to a cartridge that is vented after the plunger 1138 is depressed. As a second example, the connector 1122 may include a valve that is opened after the plunger 1138 is depressed. As a third example, the plunger 1138 may be depressed before attaching the liquid extraction device 1100 to the cartridge, and the connector 1122 may include a seal that is punctured, ruptured, or torn when the liquid extraction device 1100 is attached to the vented cartridge. Venting the liquid extraction outlet 1108 means that the liquid extraction outlet 1108 is at atmospheric pressure, while the volume of gas 21 is above atmospheric pressure. This pressure differential forces liquid through the needle 1106 and out the liquid extraction outlet 1108, thereby expelling the extracted liquid from the liquid extraction device 1100. The blood collection tube 11 can then be removed from the liquid extraction device 1100.

[0171] A modification to the tenth liquid extraction device 1100 includes two needles. The first needle is in fluid communication with the air transfer conduit 1142 and transfers air from the housing 1140 to the blood collection tube 11. The second needle provides a fluid connection to the volume of liquid 19 and provides an outlet from the liquid extraction device, with a liquid extraction outlet 1108 at atmospheric pressure. In this modified device, liquid is again extracted by creating a pressure difference between the volume of gas 21 and the liquid extraction outlet 1108 when the plunger 1138 moves from the first configuration to the second configuration. However, a pressure difference is created during the actuation of the plunger 1138 from the first configuration to the second configuration.

[0172] Specifically, actuation of the plunger 1138 transfers air from the housing 1140 through the air transfer conduit 1142 and the first needle into the blood collection tube 11, thereby increasing the pressure of the volume of gas 21 within the blood collection tube 11. Because there is a pressure differential between the volume of gas 21 and the liquid extraction outlet 1108, liquid is forced out of the second needle (e.g., into the chamber of a connected vent cartridge).

[0173] 13A-13D show an eleventh liquid extraction device 1200 being used to extract liquid from a blood collection tube 11. FIG. 13A shows the liquid extraction device 1200 prior to attachment of the blood collection tube 11. Similar to the liquid extraction device 1100 shown in FIGS. 12A-12D, the liquid extraction device 1200 uses static attachment of the blood collection tube 11 to the needle 1206, with an actuatable liquid extraction mechanism provided external to the cylinder 1202. Specifically, the liquid extraction mechanism is provided in the form of a pull tab 1244 that generates a negative pressure.

[0174] The liquid extraction device 1200 comprises a cylinder 1202 in which a blood collection tube 11 is received. The liquid extraction device 1200 also comprises a liquid reservoir interface (e.g., blood collection tube interface) in the form of a needle 1206. The cylinder 1202 comprises a septum 1226 that defines a non-vented chamber 1228 within an end of the cylinder 1202 (specifically, between the end wall 1218 and the septum 1226). The needle 1206 is fixedly attached to the septum 1226. When the blood collection tube 11 is attached to the liquid extraction device 1200, the cap 15 abuts the septum 1226.

[0175] The needle 1206 comprises a liquid extraction outlet 1208 in fluid communication with a chamber 1228. The liquid extraction device 1200 also comprises an outlet 1216 from the chamber 1228 provided in an end wall 1218. The outlet 1216 allows for the liquid extracted from the blood collection tube 11 to be removed from the liquid extraction device 1200. Furthermore, the liquid extraction device 1200 comprises a connector 1222 in fluid communication with the outlet 1216. The connector 1222 allows for the liquid extraction device 1200 to be attached to a cartridge.

[0176] The liquid extraction device 1200 further comprises an actuatable liquid extraction mechanism in the form of a pull tab 1244 joined to the housing 1240. The pull tab 1244 is movable from a first configuration (FIGS. 13A and 13B) to a second configuration (FIG. 13D). The interface between the pull tab 1244 and the housing 1240 is sealed such that air does not escape from the housing 1240 around the sides of the pull tab 1244.

[0177] 13A-13D, the housing 1240 may be attached to a side wall of the cylinder 1202. The liquid extraction mechanism also includes an air transfer conduit 1242 in fluid communication with the housing 1240 and the chamber 1228. When the pull tab 1244 is actuated (i.e., pulled) from the first configuration to the second configuration, air is forced out of the chamber 1228 and into the housing 1240 through the air transfer conduit 1242.

[0178] The procedure for extracting liquid from the blood collection tube 11 is illustrated in Figures 13A-13D. When the pull tab 1244 moves from a first configuration (Figure 13B) to a second configuration (Figure 13D), liquid is extracted by creating a pressure differential between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 1208. In the embodiment illustrated in Figures 13A-13D, the pressure differential is created during actuation of the pull tab 1244 from the first configuration to the second configuration.

[0179] The blood collection tube 11 is attached to the liquid extraction device 1200 by applying a downward force to the blood collection tube 11 such that the needle 1206 pierces the septum 17. The blood collection tube 11 is fully attached when the cap 15 abuts the septum 1226 of the cylinder 1202 (FIG. 13B).

[0180] Applying an upward force to the pull tab 1244 increases the volume of the housing 1240 (FIG. 13C). The increase in the volume of the housing 1240 draws air out of the chamber 1228 through the air transfer conduit 1242, decreasing the pressure of the air in the chamber 1228. This means that there is a pressure difference between the volume of gas 21 in the blood collection tube 11 (which is at atmospheric pressure) and the liquid extraction outlet 1208 (which is below atmospheric pressure). This pressure difference forces liquid through the needle 1206 and through the liquid extraction outlet 1208 into the chamber 1228.

[0181] Further upward movement of the pull tab 1244 maintains the negative pressure in the chamber 1228, thereby drawing more liquid from the blood collection tube 11. This continues until the pull tab 1244 reaches the second configuration shown in FIG. 13D. In this position, the volume of the housing 1240 is at a maximum and liquid is drawn from the blood collection tube 11 until the pressures in the volume of gas 21 and the liquid extraction outlet 1208 equalize.

[0182] When the blood collection tube 11 is disconnected from the liquid extraction device 1200, the chamber 1228 is vented via the needle 1206. The extracted liquid can then be aspirated from the chamber 1228 via the outlet 1216 into a chamber of the cartridge.

[0183] 14A-14D show a twelfth liquid extraction device 1300 being used to extract liquid from a blood collection tube 11. Fig. 14A shows the liquid extraction device 1300 prior to attachment of a blood collection tube 11. The liquid extraction device 1300 includes two needles 1306a, 1306b that allow for progressive extraction of liquid using positive pressure while a piston 1304 is actuated from a first configuration to a second configuration.

[0184] The liquid extraction device 1300 includes a cylinder 1302 (or tube) in which a blood collection tube 11 is received. The liquid extraction device 1300 also includes an actuatable liquid extraction mechanism in the form of a piston 1304 and a liquid reservoir interface (e.g., a blood collection tube interface) that includes a first needle 1306a and a second needle 1306b.

[0185] The cylinder 1302 includes a partition 1326 that defines a chamber 1328 in an end of the cylinder 1302. Specifically, the chamber 1328 is defined between the partition 1326 and an end wall 1318 of the cylinder 1302. The cylinder 1302 also includes an outlet 1316 that provides a fluid connection to the chamber 1328 and allows liquid extracted from the blood collection tube 11 to be removed from the liquid extraction device 1300.

[0186] A cylindrical support 1346 extends upwardly from the septum 1326. A first needle 1306a and a second needle 1306b are retained within the support 1346. The piston 1304 has an annular shape that supports the cap 15 of the blood collection tube 11 while passing around the support 1346. Two sealing elements in the form of inner and outer annular O-ring seals 1310 form seals between the piston 1304 and the cylindrical support 1346, and between the piston 1304 and the cylinder 1302.

[0187] The piston 1304, cylinder 1302, and cylindrical support 1346 together define a non-vented toroidal chamber 1320 between the piston 1304 and a septum 1326. The liquid extraction device 1300 also includes an air transfer conduit 1342 within the septum 1326 that provides a fluid connection between the chamber 1320 and the first needle 1306a. The end of the second needle 1306b is in fluid communication with a chamber 1328 at the end of the cylinder 1302 via a liquid extraction outlet 1308.

[0188] The procedure for extracting liquid from the blood collection tube 11 is illustrated in Figures 14A-14D. As with the embodiment described above, liquid is extracted by creating a pressure differential between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 1308 as the piston 1304 moves from the first configuration to the second configuration. In the embodiment illustrated in Figures 14A-14D, the pressure differential is created during actuation of the piston 1304 from the first configuration to the second configuration.

[0189] The blood collection tube 11 is attached to the liquid extraction device 1300 in a manner similar to the embodiment described above. When attached as shown in FIG. 14B (i.e., with the piston 1304 in the first configuration), there is no pressure difference between the volume of gas 21 and the liquid extraction outlet 1308.

[0190] The downward movement of the piston 1304 decreases the volume of the non-vented chamber 1320 and increases the pressure of the air within the chamber 1320. This forces air into the blood collection tube 11 via the air transfer conduit 1342 and the first needle 1306a, thereby increasing the pressure of the volume of gas 21.

[0191] At this point, there is a pressure difference between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 1308 (which is at the same pressure as the chamber 1328 at the end of the cylinder 1302). This pressure difference pushes liquid out of the blood collection tube 11 and into the chamber 1328 through the second needle 1306b and the liquid extraction outlet 1308 (as shown in FIG. 14C). In particular, air flows into the blood collection tube 11 through the first needle 1306a, while liquid flows out of the blood collection tube 11 through the second needle 1306b.

[0192] As a result of the continued downward movement of the piston 1304, air is transferred from the chamber 1320 to the blood collection tube 11, maintaining a pressure differential between the air in the blood collection tube 11 and the air in the chamber 1328. This results in a continued flow of liquid into the chamber 1328 until the piston 1304 reaches the second configuration (FIG. 14D) where it abuts the septum 1326. Liquid continues to flow into the chamber 1328 until the pressures in the volume of gas 21 and the liquid extraction outlet 1308 are equalized.

[0193] When the blood collection tube 11 is disconnected from the liquid extraction device 1300, the chamber 1328 is vented via the second needle 1306b and the liquid extraction outlet 1308. The extracted liquid can then be aspirated from the chamber 1328 of the liquid extraction device 1300 into the chamber of the cartridge.

[0194] 15A-15E show a thirteenth liquid extraction device 1400 being used to extract liquid from a blood collection tube 11. The liquid extraction device 1400 can be used to extract liquid from the blood collection tube 11 in stages. This reduces the pressure differential created between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 1408, reducing the tendency for hemolysis to occur during extraction of liquid from the blood collection tube 11.

[0195] The liquid extraction device 1400 has essentially the same structure as the liquid extraction device 300 shown in Figures 3A-3D, except that a plurality of openings (specifically, a first recess 1412a, a second recess 1412b, and a third recess 1412c) are provided in the inner side wall of the cylinder 1402. Other features of the cylinder 1402 shown in Figures 15A-15E (i.e., the stopper 1414, the outlet 1416, and the end wall 1418) have the same functions as the corresponding features of the cylinder 302 of the liquid extraction device 300 shown in Figures 3A-3D. Similarly, other features of the liquid extraction device 1400 shown in Figures 15A-15E (i.e., the piston 1404, the needle 1406, the liquid extraction outlet 1408, the O-ring seal 1410, and the chamber 1420) have the same functions as the corresponding features of the liquid extraction device 300 shown in Figures 3A-3D.

[0196] Each recess 1412 of the liquid extraction device 1400 shown in Figures 15A-15E extends around at least a portion of the circumference of the interior side wall of the cylinder 1402. Each recess 1412 provides a path for air flow around the O-ring seal 1410 when the O-ring seal 1410 is aligned with that recess 1412. A stopper 1414 is provided to align the O-ring seal with a third recess 1412c.

[0197] A procedure for extracting liquid from a blood collection tube 11 is illustrated in Figures 15A-15E. As will be explained in more detail below, as the piston 1404 moves from a first configuration to a second configuration, a pressure differential is repeatedly created between the volume of gas 21 in the blood collection tube 11 and the liquid extraction outlet 1408. Specifically, in the example illustrated in Figures 15A-15E, a pressure differential is created in response to (a) the O-ring seal 1410 of the piston 1404 being aligned with a first recess 1412a, (b) the O-ring seal 1410 of the piston 1404 being aligned with a second recess 1412b, and (c) the piston being in a second configuration (wherein the O-ring seal 1410 is aligned with a third recess 1412c).

[0198] The blood collection tube 11 is connected to the liquid extraction device 1400 in a manner similar to the liquid extraction device 300 shown in Figures 3A-3D. At this point, there is no pressure difference between the volume of gas 21 and the liquid extraction outlet 1408.

[0199] Applying a downward force to the piston 1404 reduces the volume of the chamber 1420, forcing air through the needle 1406 and into the blood collection tube 11. This increases the pressure of the gas volume 21 in the blood collection tube 11. As the piston 1404 moves further downward (to the position shown in FIG. 15B), the pressure of the air in the chamber 1420 and the blood collection tube 11 increases further until the piston 1404 reaches a first intermediate position between the first and second configurations. In the first intermediate position, the O-ring seal 1410 of the piston 1404 is aligned with the first recess 1412a (FIG. 15C). When the piston 1404 is in this position, the O-ring seal 1410 is broken, allowing air to escape around the O-ring seal 1410 through the first recess 1412a. This means that the high pressure air in the chamber 1420 is exhausted to the atmosphere. At this point, there is a pressure difference between the volume of gas 21 and the liquid extraction outlet 1408, which means that liquid is forced out of the needle 1406, through the liquid extraction outlet 1408 and into the chamber 1420 (as shown in Figure 15C).

[0200] After a portion of the liquid is extracted from the blood collection tube 11, further downward movement of the piston 1404 repressurizes the chamber 1420 and the volume of gas 21 until the piston 1404 reaches a second intermediate position between the first and second configurations. In the second intermediate position, the O-ring seal 1410 is aligned with the second recess 1412b (FIG. 15D). This breaks the O-ring seal 1410, thereby depressurizing the chamber 1420 and providing a pressure differential between the volume of gas 21 and the liquid extraction outlet 1408. This pressure differential forces more liquid out of the needle 1406 and into the chamber 1420 via the liquid extraction outlet 1408 (as shown in FIG. 15D).

[0201] Finally, as the piston 1404 moves further downward beyond the second intermediate position, the chamber 1420 and the volume of gas 21 are again repressurized until the piston 1404 reaches a second configuration (FIG. 15E) in which the O-ring seal 1410 is aligned with the third recess 1412c. This causes the O-ring seal 1410 to break, providing a pressure differential between the volume of gas 21 and the liquid extraction outlet 1408, forcing a final portion of the liquid out of the needle 1406 and into the chamber 1420 via the liquid extraction outlet 1408.

[0202] When the chamber 1420 is vented by air flow through the third recess 1412b, the liquid extracted from the blood collection tube 11 can be aspirated from the chamber 1420 into the chamber of the cartridge. The blood collection tube 11 can also be removed from the liquid extraction device 1400.

[0203] 16A-16D show a fourteenth liquid extraction device 1500 being used to extract liquid from a blood collection tube 11. The liquid extraction device 1500 extracts liquid from the blood collection tube 11 using a siphon-like effect.

[0204] The liquid extraction device comprises a cylinder 1502 having a partition 1526 that defines a chamber 1528 in an end of the cylinder 1502 (between the partition 1526 and an end wall 1518 of the cylinder 1502). An outlet 1516 is provided in a side wall of the cylinder 1502 and is in fluid communication with the chamber 1528. The outlet 1516 allows liquid extracted from the blood collection tube 11 to be removed from the chamber 1528.

[0205] The septum 1526 acts as a support for a liquid reservoir interface (e.g., a blood collection tube interface) that includes a first needle 1506a and a second needle 1506b. Each needle 1506 projects upwardly from the septum 1526 and has an end that extends partially into the chamber 1528.

[0206] The first needle 1506a is the longer of the two needles and is configured to provide a fluid connection to the volume of gas 21 in the blood collection tube 11. The second needle 1506b is shorter and is configured to provide a fluid connection to the volume of liquid 19 in the blood collection tube 11. The end of the second needle 1506b that protrudes into the chamber 1528 is the liquid extraction outlet 1508.

[0207] Unlike the above-described embodiment, operation of the liquid extraction mechanism is not required to extract liquid from the blood collection tube 11. Extraction of liquid from the blood collection tube 11 will be described with reference to Figures 16A to 16D.

[0208] The blood collection tube 11 is attached to the liquid extraction device 1500 in the same manner as in the above embodiment, and is fully attached to the liquid extraction device 1500 when the cap 15 abuts against the septum 1526 (as shown in FIG. 16B). In this position, the first needle 1506a vents the volume of gas 21 in the blood collection tube 11 to the chamber 1528 such that the pressure difference between the volume of gas 21 and the chamber 1528 is always equalized. The liquid extraction outlet 1508 is at atmospheric pressure, but there is a pressure head above the upwardly protruding end of the second needle 1506b (i.e., above the tip of the second needle 1506b). This means that there is a pressure difference between both ends of the second needle 1506b, and as a result, liquid is drawn into the chamber 1528 through the liquid extraction outlet 1508 (as shown in FIG. 16C). The extraction of liquid continues until (i) there is no pressure head above the tip of the second needle 1506b, or (ii) the liquid level in the chamber 1528 reaches the end of the first needle 1506a, such that volume 21 of gas is no longer expelled (as shown in FIG. 15D).

[0209] The blood collection tube 11 can then be removed from the liquid extraction device 1500. Once removed, the chamber 1528 is vented through the needles 1506a, 1506b, allowing extracted liquid to be aspirated from the chamber 1528 of the liquid extraction device 1500 into the chamber of the cartridge.

[0210] FIG. 18 shows a blood collection tube 11 being inserted into the cylinder of a liquid extraction device 400. In this example, the liquid extraction device 400 is integral with a cartridge 100 with the features described above with reference to FIG. 1. The blood collection tube 11 is shown inserted into the cylinder when the cartridge 100 is in a vertical orientation. FIG. 18 also shows an optically transparent window 130 in the side wall of the cartridge 100. The sample adequacy control chamber of the cartridge 100 is visible through the window 130.

[0211] Next, configurations that have been investigated for extracting liquid from a puncturable liquid reservoir are described.

[0212] Needle sizes investigated to provide a fluid connection to a puncturable liquid storage container (e.g., blood collection tube) were sizes 16G to 26G with typical lengths of 13 mm to 40 mm. Pressures generated when investigating process parameters were in the region of 100 mbar to 800 mbar, depending on the fill volume of the blood collection tube and the amount of air forced into the blood collection tube.

[0213] The primary failure mode of concern is hemolysis, which is typically in the range of 0-100 mg / dl. In general, more hemolysis occurs at (i) higher pressures (either when more air is displaced into the liquid reservoir or when the liquid reservoir has a higher fill level), (ii) higher shear stresses (either from a longer needle length or a sharper needle inlet (angled instead of flat)), and (iii) higher flow rates (when using larger sized needles, lysis can occur at the needle outlet).

[0214] Higher hematocrits slow down the flow of liquid and may even block narrow bore needles. This means that shorter needles are better for higher hematocrit samples as the flow is faster (because the shorter length creates less hydraulic resistance). The suitability of shorter needle lengths for higher hematocrit samples must be balanced against the likelihood of hemolysis and needle blockage. Shorter needles are not necessarily better for low hematocrit flows and are more likely to induce lysis at higher flow rates. A similar tradeoff exists for larger bore needles, which allow for higher flow rates and resulting faster delivery times, but with the risk of higher lysis at the needle exit. This tradeoff can be mitigated by making the exit from the needle as smooth as possible, so that the tendency of higher flow rates to induce lysis at the needle exit is minimized.

[0215] Lower pressures (e.g., 100 mbar to 300 mbar, corresponding to the introduction of 0.5 ml of air into a 1.5 ml headspace) give a much wider window of process parameters regarding needle dimensions and geometry with respect to hemolysis sensitivity. This is because very little hemolysis is observed at these pressures. The drawback is the slow delivery time. Typical blood volumes delivered are about 350 μl using 500 μl of air, as sub-milliliter volumes can be tolerated in delivery times of about 10 seconds, and implementing this pressure range is the most robust approach to combat lysis sensitivity.

[0216] The effect of a small needle bore at low operating pressures is the potential for occluded bore at high hematocrits. The effect of a larger needle bore is the risk of the tube cap coming off when the needle is removed, as well as the need for high insertion forces to puncture the septum. In general, the needle size range of 20G to 21G has been found to provide a good balance between these considerations.

[0217] Needle length is an effective way to adjust the flow rate by varying hydraulic resistance. Considerations that influence needle length include (i) the trade-off between the required flow rate, percentage hematocrit range, and risk of hemolysis, and (ii) the tip of the needle must always be below the surface of the blood at the lowest potential fill volume, thereby affecting the overall length of the device.

[0218] With regard to the needle inlet geometry, the subcutaneous opening compresses blood flow at the diamond opening resulting in high shear forces and increased lysis. Changing the needle opening profile aids in flow without localized high pressure areas.

[0219] Test results identified consistently good performance from test pressures up to 300 mbar using 20-21 G needles with lengths of 13-35 mm. Preferably, the needles are 21 G needles with lengths of 35 mm, preferably including a 30 degree tip, and more preferably including an anti-core finish. At least 300 μl of blood was extracted from Vacutainer® blood collection tubes across a blood hematocrit range of 20% to 65%, with extraction times varying from 2 seconds to 20 seconds.

[0220] Variations or modifications of the systems and methods described herein are described in the following paragraphs.

[0221] The blood extraction devices described above may include a porous medium, such as a membrane, mesh, or fabric, to achieve additional functions. The porous medium may incorporate reagents or specific surface chemistries to deplete undesired materials from the sample, or may promote reactions with specific materials to aid in further processing or analytical determinations. For example, the porous medium may be provided to induce cell lysis to expose cellular contents.

[0222] A specific example is a plasma separation membrane that filters the blood as it is extracted from the blood collection tube 11. Specifically, the plasma separation membrane may filter the blood so that the plasma is extracted by a liquid extraction device. The plasma can then be aspirated into the cartridge.

[0223] A plasma separation membrane 1600 is shown in Figure 17A pressed against the bottom of the piston. The pressure differential created by the operation of the liquid extraction mechanism draws liquid through the plasma separation membrane 1600, thereby filtering plasma from the blood.

[0224] As shown in FIG. 17B, a hydrophilic mesh 1602 may be placed on top of the plasma separation membrane 1600 (i.e., so that the extracted liquid passes through the hydrophilic mesh 1602 before passing through the plasma separation membrane 1600). This improves wetting of the membrane 1600 and ensures that the entire area of ​​the membrane is in contact with the blood, thereby improving the flow of liquid through the membrane 1600. The hydrophilic mesh 1602 also allows the device to be handled (e.g., rotated in different orientations) without affecting the plasma extraction process. Similarly, membranes and / or meshes can be placed on both sides of the plasma separation membrane 1600 to aid in extraction and provide a driving force for further fluid flow, for example, similar to lateral flow techniques.

[0225] 17C, the cylinder may have protrusions 1604 extending upward from the end wall of the cylinder and positioned to contact the plasma separation membrane 1600 when the piston is in the second configuration. These features facilitate liquid transport from the bottom of the plasma separation membrane 1600. The surface and adjacent areas of the protrusions 1604 may be provided with a material or coating that exhibits wetting properties for passive extraction of plasma.

[0226] A smaller volume chamber 1606 above the plasma separation membrane may also be implemented. The use of a smaller volume chamber 1606 improves membrane wettability and ensures that the entire area of ​​the membrane is in contact with the blood (similar to the hydrophilic mesh shown in FIG. 17B).

[0227] Finally, as shown in Figure 17D, a small distance between the plasma separation membrane 1600 and the end wall of the cylinder can be implemented, resulting in a shallow chamber 1608 (e.g., less than 100 μm in height). Again, this promotes liquid transport from the bottom surface of the plasma separation membrane 1600.

[0228] As mentioned above, other porous media may be substituted for the plasma separation membrane shown in Figures 17A-17D to provide additional functionality.

[0229] In embodiments where air is exhausted from an outlet from the liquid extraction device (i.e., an outlet in the cylinder) to provide a sudden difference in pressure between the volume of gas in the blood collection tube and the liquid extraction outlet, an air filter may be implemented downstream of the outlet from the liquid extraction device. The air filter slows down the release of air from the outlet from the liquid extraction device, which means that the pressure difference is generated more gradually rather than in a sudden step change. By controlling the pressure difference in this way, the tendency for hemolysis to occur in the extracted blood is reduced. In contrast, a sudden step change in pressure can result in aggressive extraction of blood, increasing the likelihood of hemolysis.

[0230] Although the above embodiments are described with respect to extracting liquid from a blood collection tube, such as a Vacutainer®, it will be appreciated that the above embodiments are also suitable for extracting liquid from other forms of puncturable liquid storage containers that may differ in size and / or shape from a blood collection tube. In such cases, the dimensions of the cylinder and piston may be adapted to the size and shape of the liquid storage container from which the liquid is to be extracted. For example, although the above embodiments are described with reference to a cylindrical tube in which the blood collection tube 11 is received, it will be appreciated that tubes and pistons of other cross sections may be implemented to enable extraction of liquid from other liquid storage containers.

[0231] Additionally, although the above embodiments use a liquid reservoir interface (e.g., a blood collection tube interface) in the form of one or more needles, other blood collection tube interfaces may be implemented so long as they are capable of providing a fluid connection to the volume of liquid in the liquid reservoir (e.g., to the volume of liquid 19 in the blood collection tube 11).

[0232] The term "needle" in the above embodiments is not intended to be limited to metal needles, but is intended to cover other piercing elements configured to pierce the septum of a blood collection tube, such as a piercing element integral with a piston. The needles described herein may have different configurations. For example, one or more needles used in the above embodiments may have a beveled or blunt tip, may include an anti-coring mechanism, and may be formed from a variety of materials, such as stainless steel tubing or injection molded plastic.

[0233] Although particular embodiments are described above using elastically deformable elements such as springs and bellows chambers, it will be appreciated that other elastically deformable elements (e.g., O-rings) may be implemented to provide the functionality of the elements used in these embodiments.

[0234] While certain embodiments utilize one or more sealing elements attached to the piston, the sealing elements may alternatively be attached to the inner wall of the cylinder. In embodiments utilizing recesses aligned with the sealing elements, the recesses may alternatively be provided in the surface of the piston. Although the above embodiments describe sealing elements in the form of O-ring seals, the sealing elements may alternatively be provided in the form of molded plastic seals or overmolded rubber seals.

[0235] Finally, although the above embodiments have been described with reference to a force applied by a user to activate the liquid extraction mechanism, it will be appreciated that the liquid extraction mechanism may alternatively be activated without the need for user input (e.g., under the control of a motor).

[0236] As a general point, although the above embodiments have been described with respect to extracting liquid for use in diagnostic tests performed using the cartridge, it will be appreciated that the liquid extraction device described above is suitable for extracting liquid from liquid storage containers (e.g. blood collection tubes) for a wide range of other purposes.

[0237] The singular terms "a" and "an" should not be construed to mean "only one." Rather, unless otherwise specified, they should be construed to mean "at least one" or "one or more." The word "comprising" and its derivatives, including "comprises" and "comprise," includes each of the features listed but does not exclude that one or more additional features are also included.

[0238] The above embodiments have been described by way of example only, and the described embodiments are to be considered in all respects only as illustrative and not restrictive. It will be understood that modifications of the described embodiments can be made without departing from the scope of the invention. It will also be apparent that there are many variations which have not been described but which are within the scope of the appended claims.

Claims

1. 1. A liquid extraction device for extracting liquid from a puncturable liquid storage container, comprising: a liquid reservoir interface configured to provide a fluid connection to a volume of liquid in the liquid reservoir, the liquid reservoir interface comprising a liquid extraction outlet configured to allow liquid to be extracted from the liquid reservoir; a liquid extraction mechanism operable from a first configuration to a second configuration; Equipped with A liquid extraction device, wherein the liquid extraction mechanism is configured to provide a pressure differential between a volume of gas in the liquid storage container and the liquid extraction outlet when the liquid extraction mechanism is actuated from the first configuration to the second configuration.

2. The liquid extraction device of claim 1 , wherein the liquid reservoir interface is configured to allow removal of the liquid reservoir from the liquid reservoir interface after extraction of liquid from the liquid reservoir.

3. The liquid extraction device of claim 1 , wherein the liquid reservoir interface comprises at least one needle configured to provide the fluid connection to the volume of liquid in the liquid reservoir.

4. The liquid extraction device of claim 1 , wherein the liquid extraction mechanism comprises a piston movable within a receptacle, the piston being actuatable from the first configuration to the second configuration.

5. The liquid extraction device of claim 4 , wherein the liquid reservoir interface is attached to the piston.

6. The liquid extraction device of claim 4 , wherein the liquid extraction outlet is in fluid communication with a chamber defined by the piston and the receptacle, the chamber being in fluid communication with the liquid extraction outlet.

7. 7. The liquid extraction device of claim 6, wherein the piston is configured to increase the pressure of air in the chamber when the piston is actuated from the first configuration to the second configuration.

8. The liquid extraction device of claim 7 , further comprising a sealing element configured to provide a seal between the piston and the receptacle when the piston is in the first configuration.

9. 9. The liquid extraction device of claim 8, wherein the liquid extraction mechanism is configured to provide the pressure differential between the volume of gas in the liquid storage vessel and the liquid extraction outlet when the liquid extraction mechanism is in the second configuration.

10. 10. The liquid extraction device of claim 9, further comprising a seal failure element configured to fail the seal element when the piston is in the second configuration.

11. 11. The liquid extraction device of claim 10, wherein the seal-breaking element includes an opening configured to break the seal element when the piston is in the second configuration, such that air within the chamber is released through the opening.

12. The liquid extraction device of claim 11 , further comprising an air filter configured to control the flow of air emitted through the opening.

13. 11. The liquid extraction device of claim 10, wherein the seal failure element is a first seal failure element, and the liquid extraction device further comprises a second seal failure element configured to fail the seal element when the piston is actuated to a position between the first configuration and the second configuration.

14. 7. The liquid extraction device of claim 6, wherein the liquid extraction mechanism is configured to provide the pressure differential between the volume of gas in the liquid storage container and the liquid extraction outlet during operation of the liquid extraction mechanism from the first configuration to the second configuration.

15. 15. The liquid extraction device of claim 14, wherein the piston is configured to reduce the pressure in the chamber below the pressure of the volume of gas in the liquid storage vessel when the piston is actuated from the first configuration to the second configuration.

16. the liquid reservoir interface comprises at least two needles; a first needle of the at least two needles configured to provide the fluid connection to the volume of liquid in the liquid storage container, the first needle of the at least two needles in fluid communication with the liquid extraction outlet; a second needle of the at least two needles configured to provide a fluid connection to the liquid reservoir; The liquid extraction device of claim 14 , wherein the liquid extraction mechanism is configured to supply air through the second needle of the at least two needles.

17. 5. The liquid extraction device of claim 4, further comprising a resiliently deformable element configured to bias the piston outwardly from the first configuration towards the second configuration.

18. 18. The liquid extraction device of claim 17, further comprising at least one clip configured to hold the piston in the first configuration in which the elastically deformable element is in a deformed state.

19. The liquid extraction device of claim 1 , further comprising a porous medium in fluid communication with the liquid extraction outlet.

20. 1. A liquid extraction device for extracting liquid from a puncturable liquid storage container, comprising: a chamber, the chamber comprising an outlet configured to vent the chamber; a first liquid reservoir interface configured to provide a fluid connection to a volume of liquid in the liquid reservoir, the first liquid reservoir interface comprising a liquid extraction outlet in fluid communication with the chamber; a second liquid reservoir interface configured to provide a fluid connection to a volume of gas in the liquid reservoir, the second liquid reservoir interface configured to evacuate the volume of gas; and A liquid extraction device comprising:

21. A liquid treatment device, comprising: a liquid treatment device comprising one or more conduits; A liquid extraction device according to any one of claims 1 to 20. Equipped with The liquid extraction device is in fluid communication with at least one of the one or more conduits.

22. 22. A liquid treatment apparatus according to claim 21, wherein the liquid extraction device is integrated within the liquid treatment device.

23. 22. A liquid treatment apparatus according to claim 21, wherein the liquid extraction device is attachable to the liquid treatment device.

24. 24. A liquid treatment apparatus according to claim 23, wherein the liquid extraction device is removably attachable to the liquid treatment device.

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