HK1160516A - Disposable dispensing cartridge for medical assay instrumentation - Google Patents

Description

Disposable dispensing cartridge for medical assay instruments

Technical Field

The present invention relates to disposable dispensing cartridges, and more particularly to disposable dispensing cartridges for medical assay instruments such as immunoassays that are simple and inexpensive to manufacture.

Background

Medical assay instruments require the use of reagents and/or samples that are stored in the machine and added to the prepared sample, such as a blood sample in an immunoassay. In a typical medical testing instrument, a prepared sample is added to a test tube or other container mounted on the machine. The particular reagents required for a given test are brought into position from a tray or carousel containing a number of different reagents. When in place, the reagent container is opened and a dropper is inserted into the reagent to extract a volume of fluid. The pipette is then moved by the machine to a position directly above the cuvette and the required volume of reagent is typically dispensed into the cuvette by a positive displacement pump, such as a syringe driven by a stepper motor. After dispensing the reagent, the pipette is then moved out of position, the pipette tip is rinsed and rinsed, or alternatively discarded in the case of a disposable pipette. This dispensing process is complex and expensive, particularly when the pipette is rinsed and rinsed after each dispensing of reagent. Furthermore, the machine needs to move the pipette from the reagent container to the cuvette and then to another location where the wash pipette is located. Such movement increases the complexity of the machine, resulting in an increased risk of component failure. In addition, the movement of the machine results in a longer cycle time for each reagent dispense. This in turn limits the throughput of the machine and thus the speed at which the laboratory returns test results to the health care professional.

A known solution to this problem is to provide a cassette containing a reagent reservoir and a multi-purpose dispensing tube. This solution is advantageous because the dispensing tube does not need to be flushed or discarded after each dispensing. Moreover, the movement of the machine is limited to the transfer of the desired cartridge to the dispensing station. As soon as the transfer of the reagent is completed, the next reagent cartridge will be brought into position.

In WO 2005/019092, a reagent dispensing cartridge comprises a reagent reservoir, a reagent dispensing assembly in communication with the reagent reservoir, and an actuator assembly. The reagent dispensing assembly includes a reagent metering chamber, a piston that moves within the metering chamber, and two spring-loaded check ball valves. The reagent reservoir includes a collapsible fluid bladder supported in a rigid shell. Displacement of the piston in one direction causes an amount of fluid to enter the metering chamber through a valve located between the fluid reservoir and the metering chamber, and displacement of the piston in the other direction causes fluid to exit the metering chamber. However, the dispensing cartridge is complex to manufacture and is not disposable.

WO 2006/048643 discloses a dispensing system that dispenses sub-milliliter volumes of reagent and includes a cartridge, an armature, and a nozzle assembly. The cartridge includes a hollow body divided by a valve seat into a first chamber and a second chamber. The first chamber forms a reservoir which, in use, holds a reagent to be dispensed by the system. The second cavity defines an axial armature bore in which the armature is movable. The nozzle assembly retains the armature in the bore. The reagent dispensing system also includes a solenoid coil of conventional construction having an orifice. The second chamber of the cartridge is adapted to be mounted within the bore, thereby causing the magnetic field generated by the coil to move the armature. Movement of the armature causes reagent from the reservoir to be expelled through the nozzle assembly. Here, the disposable part comprising the cartridge, the armature and the nozzle assembly is rather complex and expensive to manufacture.

The kit disclosed in patent WO 2007/122387 comprises a reagent reservoir in communication with a deformable dispensing tube which is at least partially compressible to dispense a known volume of reagent from the tube. The compression of the tube is performed by a hammer actuated by a piezoelectric actuator. Disposable cartridges, while simple, are inconvenient to use. In fact, since the tube has a very small internal diameter, the volume of fluid dispensed by one penetration of the tube is of the order of 100 nanoliters. Dispensing larger volumes of reagent requires circulating the ram, which may slow down the dispensing operation. Moreover, dispensing precise volumes of reagent requires careful alignment of the tube and the hammer, an operation that must be performed for each cassette, and requires special skill training for the operator.

Disclosure of Invention

The present application discloses a disposable dispensing cartridge that overcomes at least some of the limitations of the prior art.

According to various embodiments, a disposable dispense cassette may comprise: a reservoir adapted to contain a solvent to be dispensed; a chamber in fluid communication with the reservoir through a first one-way valve, the chamber comprising an outlet portion and a second connection portion, the outlet portion comprising a second one-way valve that allows solvent to exit the chamber; wherein the disposable cartridge is connectable to a pressure control device through the second connection portion, the pressure control device being adapted to apply a reduced pressure within the chamber to draw a predetermined volume of solvent from the reservoir through the first one-way valve into the chamber; and adapted to apply an elevated pressure within the chamber, drawing a defined volume of solvent out of the chamber via the second one-way valve; and wherein the second connection portion comprises a check valve arranged to allow gas, but not solvent, to flow into and/or out of the chamber via the second connection portion.

In an embodiment, the check valve may be a liquid-tight, gas-permeable membrane.

In another embodiment, the check valve may further comprise a movable part loaded with a compression spring, the movable part being arranged to block or open a gas passage when the pressure control device is disconnected from or connected to the disposable cartridge, respectively.

In yet another embodiment, the reservoir is removably attachable to the chamber.

In yet another embodiment, the reservoir may comprise a spout which may fit into the first connecting portion of the chamber, thereby attaching the reservoir to the chamber.

In yet another embodiment, the first one-way valve may be included in the first connection portion.

In yet another embodiment, the reservoir may comprise a flexible portion adapted to deform to equalize pressure within the reservoir when the predetermined volume of solvent is drawn from the reservoir. The reservoir may be a flexible bag.

In yet another embodiment, the disposable cartridge may further comprise agitation means arranged to agitate the solvent contained within the reservoir.

In a further embodiment, the agitation means may comprise excitation means and a rod excited by the excitation means to cause the reservoir to vibrate.

In a further embodiment, the rod may be a magnetic rod having two opposite poles and the excitation means is an excitation coil.

In yet another embodiment, the rod may be L-shaped and a portion of the rod is disposed within the excitation coil such that another portion rotates when the excitation device is actuated.

In yet another embodiment, the first and second one-way valves may be duckbill valves.

In yet another embodiment, the chamber may be a capillary tube.

In yet another embodiment, the chamber may be adapted to hold a predetermined volume of solvent comprised between 10 μ l and 100 μ l.

The disposable cartridges disclosed herein do not include the pressure control device or any mechanism for drawing solvent into or out of the chamber, and are therefore simple and inexpensive to manufacture. Moreover, the disclosed disposable cartridge is suitable for efficiently and quickly delivering the amount of solvent required in a typical medical assay instrument, for example dispensing a volume of solvent comprised in the range between 10 μ l and 100 μ l.

Drawings

The invention will be better understood by means of the description of an embodiment illustrated by way of example and by fig. 1, fig. 1 representing a disposable portion capsule according to an embodiment.

Detailed Description

Fig. 1 represents a cross-sectional view of a disposable portion capsule 1 according to an embodiment. The disposable cartridge 1 comprises a reservoir 2 to be filled with a solvent such as a reagent or a sample and a chamber 3 having a fixed volume. The chamber 3 is in fluid communication with the reservoir 2 through a first one-way valve 4, which first one-way valve 4 allows solvent to flow from the reservoir 2 into the chamber 3, but not in the opposite direction.

In the embodiment of fig. 1, the reservoir is a flexible reservoir 2, for example made of a flexible layer material, for example a polymeric film, welded around its periphery to form a bag. The reservoir 2 comprises a spout 11 preferably made of a rigid material. The spout 11 is connected to the chamber 3 such that the reservoir 2 is removably attached to the chamber 3. In the example of fig. 1, the flexible reservoir 2 is removably attached to the chamber 3 by fitting the spout 11 into a first connection portion 19 in fluid communication with the chamber 3, the first connection portion 19 comprising the first one-way valve 4. The reservoir 2 is filled with solvent through the spout 11 or through a separating plug 20 that seals the aperture in the flexible reservoir 2. As solvent is pumped into the chamber 3, the flexible reservoir 2 collapses in a controlled manner until the solvent can be substantially emptied.

An advantage of the cartridge configuration comprising the removably attached reservoir 2 is that the solvent in the reservoir 2 is not in contact with air or gas when a volume of solvent is drawn into the capillary tube 3 during a dispensing operation. Moreover, the solvent can be easily changed in the distribution box 1, if necessary.

Other configurations of the reservoir 2 are also possible. For example, the reservoir 2 may comprise a rigid portion and a flexible portion, thereby providing a variable volume of solvent within the reservoir 2 without requiring air or gas introduction in the reservoir 2 during dispensing. For example, the reservoir 2 may comprise a deformable membrane (not shown) and/or a bellows (also not shown) adapted to deform or collapse in accordance with the volume of solvent drawn from the reservoir 2 into the chamber 3, thereby equalizing the pressure within the reservoir 2. In the example of fig. 1, the chamber 3 has a capillary shape extending into the reservoir 2 and comprising an outlet portion 8 at the lower end of the chamber 3. The outlet portion 8 comprises a second one-way valve 5 which allows the solvent to exit the chamber 3 through the outlet portion 8, but not in the opposite direction. The upper end of the chamber 3 forms a second connection portion 9. This preferred configuration allows reducing the size of the disposable cartridge 1. Alternatively, the cartridge 1 may also be arranged such that the outlet portion 8 extends from the base of the reservoir 2 out of the reservoir 2 and the second connection portion 9 extends from the top of the reservoir 2.

In an embodiment, the disposable cartridge 1 is constituted by a two-part housing 12 (only a part of which is visible in fig. 1) surrounding the reservoir 2. Each part of the two-piece housing 12 may be secured together using screws (not shown), or using any other convenient fastening method, allowing for easy opening of the two parts of the case 1. When opened, reservoir 2 may be attached to chamber 3 or removed from chamber 3. The two-part housing 12 may be made of a plastic molded part.

In a preferred variant of embodiment, the cartridge 1 comprising the reservoir 2 and the chamber 3 is made in a single piece, for example by a plastic moulding manufacturing process.

The second connection portion 9 of the chamber 3 is intended to be connected to a pressure control device (not shown). During a dispensing operation, the pressure control means applies a reduced pressure within the chamber 3, thereby drawing solvent from the reservoir 2 through the first one-way valve and into the chamber 3. After a predetermined volume of solvent has been maintained in the chamber 3, the pressure control means applies an elevated pressure in the chamber 3 and a determined volume of solvent flows out of the chamber 3 through the one-way valve 5 and the outlet portion 8.

In an embodiment not shown, the pressure means comprise an in-out type pump, allowing the chamber 3 to be at an elevated pressure or a reduced pressure. The pressure device may further comprise a flow meter for accurately measuring a volume of solvent, for example with an accuracy of the order of a few nanoliters. The pressure device may further comprise a control circuit connected to the pump and the flow meter, the control circuit controlling the pump in dependence of the volume measured by the flow meter, e.g. actuating the pump to start pumping solvent into the chamber 3 or to deactivate the pump when it is determined that a volume of solvent has been pumped into the chamber 3.

Other arrangements of the pressure means are also possible. For example, the pressure device may be a vent system including an actuator to effect movement of the piston, or any other device capable of placing the capillary tube at an elevated or reduced pressure.

In the embodiment of fig. 1, the second connection portion 9 comprises a check valve 6, which is formed by a liquid-tight but gas-permeable membrane 21. For example, the diaphragm 21 may be a porous polytetrafluoroethylene diaphragm that allows the pressure control device to apply a reduced or elevated pressure within the chamber 3 while avoiding solvent flow through the check valve 6. Other configurations of the check valve 6 are possible as long as the valve 6 is adapted to allow gas, but not solvent, to flow into and/or out of the chamber 3 through the second connection portion 9. In this configuration, when the pressure control device is connected to the disposable cartridge 1, a reduced or increased pressure can be applied into the chamber 3, and when the pressure control device is disconnected from the disposable cartridge 1, the pressure in the chamber 3 remains constant.

In another embodiment, shown in fig. 1, the check valve 6 further comprises a movable part 10 loaded with a compression spring 17. When the pressure control device is disconnected from the disposable cartridge 1, the movable portion 10 is pushed upwards inside the second connecting portion 9 by the spring 17, the side wall of the movable portion 10 abuts against the inner wall of the second connecting portion 9, blocking the gas passage. Once the pressure control means is connected to the second connection portion 9, the movable portion moves downwards within a portion of the second connection portion 9 having an inner diameter larger than the rest of the connection portion 9, so that the movable portion 10 opens the gas passage. The movable part 10 may comprise a seal 23, such as an O-ring, to ensure a good seal. Alternatively, the check valve 6 may be formed by the movable portion 10 and the spring 17, without including the diaphragm 21.

The disposable cartridge 1 disclosed herein does not include the pressure control device itself or any mechanism for drawing solvent to and from the chamber 8, and is therefore simpler and less expensive than conventional disposable cartridges. The disposable cartridge 1 can be easily connected and disconnected from the pressure control device during the connection and/or disconnection process, while maintaining the measured volume of solvent in the chamber 8 if required.

In the embodiment of fig. 1, the first and second one-way valves are duckbill valves made of silicone or any other flexible material, such as rubber or synthetic elastomer. Each of the two duckbill valves 4, 5 may include two lips (not shown) and an integral base (also not shown), thereby defining a generally cylindrical opening. In the closed position, the lips abut each other, thereby preventing the passage of solvent. In the open position, the lip responds to positive pressure by spreading apart, thereby allowing the solvent to flow at the desired pressure.

The one-way valves 4, 5 may be any other type of one-way valve as long as the function of the valve does not damage the components of the solvent, such as red blood cells, when the solvent flows through the valve 4, 5. Possible alternatives for the one-way valves 4, 5 typically include diaphragm check valves, swing check valves, flap valves.

A needle (not shown) may be connected to the outlet portion 8 of the chamber 3. The needle may be replaced, for example, between each dispensing operation, or may be discarded along with the entire cartridge 1. In the latter case, the needle may be fixedly attached to the outlet portion 8 and possibly made in one piece with the disposable cartridge 1 itself.

In another variant of embodiment, the outlet portion 8 does not comprise a needle and the second duckbill valve 5 acts as an outlet nozzle. Alternatively, the end of the outlet portion 8 is pointed and the second duckbill valve 5 is located just above or within the pointed end of the outlet portion 8.

The disposable cartridge 1 disclosed herein may be sized for its use in a medical testing instrument. For example, the disposable cartridge 1 may be adapted to accurately dispense a volume of solvent comprised in the range between 10 μ l and 100 μ l. For this purpose, the fixed volume of capillary tube 3 may have a volume capable of holding a quantity of solvent comprised in the range between 10 μ l and 100 μ l.

A plurality of the disposable cartridges 1 disclosed herein may be used in a device (not shown) for performing a medical assay. During a dispensing operation, one or more disposable cartridges 1 having reservoirs 2 filled with solvent may be displaced from a storage position of the device towards one or more dispensing positions of the device at which dispensing of the solvent is to be performed. Each of the disposable cartridges 1 may include an information support (not shown), such as a bar code or located on an outer surface of the cartridge 1, or alternatively, an RFID tag attached to the disposable cartridge 1 is stored or used in magnetic form. Each of the one or more dispensing locations may comprise a reader (also not shown) for reading the information contained in the information support. The reader may be an optical reader for reading bar codes or include a short-range reading circuit for reading RFID tags.

In an embodiment, the disposable cartridge 1 further comprises agitation means 7 arranged to agitate the solvent comprised in the reservoir 2. For example, in the case where the reservoir 2 contains a blood sample including platelets and serum, the platelets may separate from the serum and settle on the bottom of the reservoir 2 over time when the sample is not agitated. The agitation means 7 can then advantageously be used to re-disperse the platelets in the serum.

In the example of fig. 1, the agitation means is formed by a reciprocating actuator 7 comprising a rod 13 and an excitation means 14. The excitation means 14 are adapted to oscillate the rod 13 linearly, as indicated by the double arrow in fig. 1, and to vibrate the reservoir 2 in accordance with the oscillating movement of the rod 13. The rod 13 may be mounted coaxially in a guide 15 fixed to the cartridge housing 12. In the exemplary embodiment of fig. 1, the rod is a magnetic rod comprising two opposite poles and can be actuated by an excitation coil 14 supplied by an alternating current.

Other configurations of the agitation means 7 are also possible. For example, the rod 13 may be L-shaped and a portion of the rod is arranged within the excitation coil 14 such that the other portion rotates when the excitation device 14 is actuated. In an embodiment not shown, the lever 13 is moved by mechanical means, for example by connecting the lever 13 to a conventional cam device (not shown). Alternatively, the agitation means 7 may be based on ultrasound treatment, such as an ultrasound probe.

The disclosure is susceptible to various modifications and alternative forms, and specific examples thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the disclosure is not to be limited to the particular forms or methods disclosed, but to the contrary, the disclosure is to cover all modifications, equivalents, and alternatives.

For example, in an embodiment not shown, the reservoir 2 is made of a rigid material and comprises a vent hole for allowing gas to enter the reservoir 2 to equalize the pressure inside the reservoir 2 when dispensing the reagent. A vent hole may be included in the plug 20. The rigid reservoir 2 is further defined by the enclosed volume provided by the two-part housing 12. In the latter configuration, the secure two-piece housing 12 should be provided with a liquid-tight seal. In the latter configuration, the first one-way valve 4 is preferably placed near the lower wall of the housing 12 having the outlet portion 8, and the second one-way valve 5 may extend outside the housing 12, so as to maximize the drainage of the solvent into the chamber 3 and out of the reservoir 2. The inclined shape of the lower wall of the housing 12 as shown in fig. 1 may further optimize solvent drainage. The reservoir 2 may also be arranged around the chamber 3, which may allow for a more compact geometry of the cartridge 1. The cartridge 1 may also have a cylindrical cross-section. In the latter case, the reservoir 2 may be concentric with the chamber 3, resulting in a compact disposable cartridge 1.

Reference numerals and features

1 Disposable dispensing Box

2 reservoir

3 Chamber

4 first check valve

5 second check valve

6 check valve

7 agitating device

8 outlet section

9 second connection part

10 movable part

11 nozzle

12 two-piece housing

13 bar

14 exciting coil

15 guide member

17 spring

19 first connection part

20 plugs

21 diaphragm

23 sealing element.

Claims (15)

1. A disposable dispensing cartridge comprising:

a reservoir adapted to contain a solvent to be dispensed;

a chamber in fluid communication with the reservoir through a first one-way valve disposed between the reservoir and the chamber such that solvent can flow directly from the reservoir into the chamber through the first one-way valve, the chamber including an outlet portion at a first end of the chamber and a second connection portion at an opposite second end of the chamber, the outlet portion of the chamber including a second one-way valve that allows solvent to flow in a direction away from the chamber; wherein the content of the first and second substances,

the disposable cartridge being connectable to a pressure control device through the second connection portion, the pressure control device being adapted to apply a reduced pressure within the chamber, drawing a predetermined volume of solvent from the reservoir into the chamber via the first one-way valve; and adapted to apply an elevated pressure within the chamber to draw the predetermined volume of solvent out of the chamber via the second one-way valve; and wherein

The second connection portion comprises a check valve arranged to allow gas, but not solvent, to flow into and/or out of the chamber via the second connection portion.

2. The disposable dispensing cartridge of claim 1, wherein the check valve comprises a liquid-tight, gas-permeable membrane.

3. The disposable dispensing cartridge of claim 1, wherein the check valve further comprises a movable portion loaded with a compression spring, the movable portion being arranged to block or open a gas passage when the pressure control device is disconnected from or connected to the disposable cartridge, respectively.

4. The disposable dispense cartridge of claim 1 wherein said reservoir is removably attached to said chamber.

5. The disposable dispensing cartridge of claim 4, wherein the reservoir comprises a spout that can be fitted into the first connection portion of the chamber, thereby attaching the reservoir to the chamber.

6. The disposable dispensing cartridge of claim 5, wherein the first one-way valve is included in the first connecting portion.

7. The disposable dispensing cartridge of claim 1, wherein the reservoir includes a flexible portion adapted to deform upon said drawing of a predetermined volume of solvent from the reservoir to equalize pressure within the reservoir.

8. The disposable dispensing cartridge of claim 7, wherein the reservoir is a flexible bag.

9. The disposable dispensing cartridge of claim 1, further comprising an agitation device arranged to agitate the solvent contained within the reservoir, a portion of the agitation device being located within the interior of the reservoir.

10. The disposable dispensing cartridge of claim 9, wherein the agitation means comprises an excitation means and a lever that is excited by the excitation means to cause the reservoir to vibrate.

11. The disposable dispensing cartridge of claim 10, wherein the lever is a magnetic lever having two opposite poles and the energizing means is an energizing coil.

12. The disposable dispensing cartridge of claim 11, wherein the lever is L-shaped and a portion of the lever is disposed within the excitation coil such that another portion rotates when the excitation device is actuated.

13. The disposable dispensing cartridge of claim 1, wherein the first and second one-way valves are duckbill valves.

14. The disposable dispense cartridge of claim 1 wherein said chamber is a capillary tube.

15. The disposable dispense cartridge of claim 1 wherein said chamber is adapted to hold a predetermined volume of solvent comprised between 10 μ l and 100 μ l.