Test apparatus, press-in method, and microfluidic device

Abstract

The present application relates to a test device that uses a microfluidic device to perform a test using a test liquid containing a test object. The test device includes a pressurizing section connected to a first opening, an opening / closing section that switches the open / close state of a second opening, and a control section that controls the pressurizing section and the opening / closing section. The control section controls the pressurizing section to pressurize the test liquid into the microfluidic device with the second opening closed by the opening / closing section, and controls the opening / closing section to open the second opening after the test liquid is pressed into the microfluidic device, and the pressurizing section to apply air pressure to the test liquid in the branch flow path to recover the test liquid into a recovery section.

Description

Technical Field

[0001] This disclosure relates to a test apparatus, a pressing method, and a microflow circuit device for measuring the pressure applied to a test flow circuit. Background Technology

[0002] To test the susceptibility of bacteria to antimicrobial agents, methods using microfluidic devices are known, such as those described in Japanese Patent Application Publication No. 2017-67620. For example, in Japanese Patent Application Publication No. 2017-67620, a microfluidic device is described that has an inlet and an outlet connected to the outside, and a flow path through which test liquid supplied from the inlet flows towards the outlet. Test liquid, initially introduced by pressurizing air from the inlet into the flow path, is then introduced into the fine flow path. A reaction section is provided in the flow path to store the test liquid supplied from the inlet, and an agent disposed in this reaction section acts on the bacteria. Summary of the Invention

[0003] It is known that when a microfluidic path is filled with test fluid, methods using capillary action and pressure, such as the method of injecting air as described in Japanese Patent Application Publication No. 2017-67620, are effective methods for reliably and rapidly filling the microfluidic path with test fluid. However, when test fluid is injected into a microfluidic device branching into multiple flow paths from a single inlet, differences in the liquid level (hydraulic head) sometimes occur between the flow paths or in the portion reaching each flow path from the inlet. This difference can cause flow within the test fluid in each flow path. If flow occurs within the test fluid in the reaction section, it may be impossible to observe accurate results.

[0004] This disclosure was made to solve such problems by providing a test apparatus, injection method, and microflow device that can suppress the flow of test fluid generated within the flow path to observe correct results.

[0005] The test apparatus disclosed herein is a test apparatus for performing tests using a test solution containing a sample using a microfluidic device. The microfluidic device has: a first opening for receiving the test solution; multiple branch flow paths communicating with the first opening; multiple microfluidic paths communicating with each branch flow path; a recovery unit disposed at the end opposite to the side of each branch flow path communicating with the first opening, for recovering a portion of the test solution; a second opening disposed at the recovery unit. The test apparatus includes a pressurizing unit connected to the first opening, which applies air pressure to force the test solution into the microfluidic path; an opening / closing unit for switching the opening and closing states of the second opening; and a control unit for controlling the pressurizing unit and the opening / closing unit. The control unit controls the second opening to be closed by the opening / closing unit, and the test solution is forcefully injected into the microfluidic path by the pressurizing unit. After the test solution is forcefully injected into the microfluidic path, the control unit controls the second opening to be opened by the opening / closing unit, and the test solution in the branch flow paths is recovered to the recovery unit by applying air pressure from the pressurizing unit.

[0006] The injection method disclosed herein is a method of injecting a test solution containing a sample into a microfluidic device. The microfluidic device has: a first opening for receiving the test solution; multiple branch flow paths communicating with the first opening; multiple microfluidic paths communicating with each branch flow path; a recovery section disposed at the end opposite to the side of each branch flow path communicating with the first opening, for recovering a portion of the test solution; and a second opening disposed in the recovery section. The injection method includes: closing the second opening; connecting a pipette that has aspirated the test solution to the first opening; injecting the test solution into the microfluidic path by discharging the aspirated test solution into the first opening; opening the second opening; and applying air pressure by the pipette to recover the test solution from the branch flow paths to the recovery section.

[0007] The microfluidic device disclosed herein is a microfluidic device used in tests using a test solution containing a sample, comprising: a first opening for receiving the test solution; a plurality of branch flow paths communicating with the first opening; a plurality of microflow paths communicating with each of the branch flow paths; a recovery section disposed at the end of each branch flow path opposite to the side communicating with the first opening, for recovering a portion of the test solution; and a second opening disposed in the recovery section.

[0008] The foregoing description, as well as other objects, features, aspects, and advantages of the invention, will become apparent from the following detailed description relating to the invention, which will be understood in conjunction with the accompanying drawings. Attached Figure Description

[0009] Figure 1 This is a diagram showing an example of the overall configuration of the test apparatus according to this embodiment.

[0010] Figure 2 This is a diagram showing an example of the peripheral configuration of the pipette nozzle in the test apparatus of this embodiment.

[0011] Figure 3 This is a block diagram illustrating the control of the test apparatus in this embodiment.

[0012] Figure 4 This is a diagram illustrating an example of the configuration of the microflow device according to this embodiment.

[0013] Figure 5 This is a diagram illustrating an example of the flow path configuration for injecting test fluid into the microfluidic device of this embodiment.

[0014] Figure 6 This is a diagram showing the state after the test fluid is injected into the flow path of the microfluidic device of this embodiment.

[0015] Figure 7 This is a diagram showing the state after the test liquid is discharged from the branch flow path of the microfluidic device of this embodiment.

[0016] Figure 8 This is a diagram illustrating a method for discharging test liquid from a branch flow path of the microfluidic device of this embodiment.

[0017] Figure 9 This is a diagram showing the state of the opening of the microfluidic device in this embodiment coated with sealing material.

[0018] Figure 10 This is a flowchart illustrating the pressing method of the test apparatus in this embodiment.

[0019] Figure 11A This is a partial top view of a branch flow path connected to multiple microflow paths, where a recovery section is provided at the end.

[0020] Figure 11B yes Figure 11A The cross-sectional view at the cutting line I of the recycling section shown.

[0021] Figure 11C This is a diagram showing a modified example of the recycling section. Detailed Implementation

[0022] Hereinafter, this embodiment will be described in detail with reference to the accompanying drawings. Furthermore, the same or equivalent reference numerals used in the drawings will not be repeated.

[0023] [Device Composition]

[0024] Figure 1 This is a diagram showing an example of the overall configuration of the test apparatus according to this embodiment. Figure 2 This is a diagram illustrating an example of the peripheral configuration of the pipette nozzle in the test apparatus of this embodiment. Figure 3 This is a block diagram illustrating the control of the test apparatus of this embodiment. It should be noted that the test apparatus of this disclosure is an apparatus for measuring the test solution by injecting a test solution containing a sample into the microfluidic path of a microfluidic device. As an example, the following describes an example of injecting a test solution into the microfluidic path to measure the sensitivity of bacteria to an antibacterial agent (pharmaceutical). The test solution contains a sample. The sample may also be a bacterium (in a specific example, a pathogenic bacterium). In a specific example, the test solution may also be a bacterial suspension. Of course, the test apparatus of this disclosure is not limited to the above-described test solution as long as the test solution is injected into the microfluidic path of the microfluidic device.

[0025] Reference Figures 1-3 The test apparatus 100 includes a test liquid setting unit 10, a pipette nozzle driving unit 12, a platform driving unit 13, a pump 14, a pipette nozzle 15, a platform 16, an opening and closing unit 30, an opening and closing driving unit 31, a coating unit 32, a pump 33, a coating driving unit 34, and a control unit 50.

[0026] The test solution setting section 10 is a bracket capable of arranging multiple test solution containers 5 containing test solutions. The test solution setting section 10 can arrange multiple test solution containers 5 relative to the test apparatus 100 on a bracket basis.

[0027] The pipette nozzle 15 is fitted with a detachable pipette nozzle 1, through which the test solution is drawn from or discharged from the test solution container 5. The pipette nozzle drive unit 12 enables the pump 14 connected to the pipette nozzle 15 and the pipette nozzle 15 to move horizontally and vertically. The pipette nozzle drive unit 12 can, for example, use an electromagnetic actuator or a stepper motor to freely move the pipette nozzle 15.

[0028] Platform 16 is a support component for mounting microfluidic devices. Platform 16 is formed in the shape of a flat plate, and the microfluidic devices are fixed to its upper surface. Platform drive unit 13 enables platform 16 to move horizontally. Platform drive unit 13 can, for example, move platform 16 freely via an electromagnetic actuator or a stepper motor. Alternatively, platform drive unit 13 can move platform 16 vertically without moving pipette nozzle 15 vertically. Furthermore, at least pipette nozzle drive unit 12 and platform drive unit 13 are moving mechanisms for changing the relative position of pipette nozzle 15 and microfluidic devices.

[0029] Although not shown, pump 14 includes, for example, a syringe, a plunger that reciprocates within the syringe, and a drive motor for driving the plunger. When connected to pipette nozzle 15 via piping, pump 14, by reciprocating the plunger, can adjust the air pressure within pipette nozzle 1 to draw the test solution into pipette nozzle 1 or to expel the test solution from pipette nozzle 1. Furthermore, while expelling the test solution from pipette nozzle 1, pump 14 can further move the plunger towards the syringe, thereby expelling air from pipette nozzle 1.

[0030] The opening / closing part 30 is a mechanism for opening and closing the opening (second opening) of the microfluidic device described later. Specifically, the opening / closing part 30 is a mechanism that controls the opening to a closed state by blocking the opening with an elastic member; for example, silicone resin 30a is provided at the front end of the rod-shaped support. The opening / closing part 30 is installed at a predetermined position relative to the pipette nozzle 15, and therefore moves to the position of the second opening by moving the pipette nozzle 15 to the opening (first opening) of the microfluidic device. The opening / closing drive part 31 drives the opening / closing part 30, which has moved to the position of the second opening, causing the silicone resin 30a to move up and down, pushing the silicone resin 30a to the second opening and blocking it, thus controlling the second opening to a closed state. In addition, in Figure 1 and Figure 2For the purpose of simplification, only one opening / closing part 30 is shown in the diagram. Multiple opening / closing parts 30 are provided as needed for the number of second openings to be opened and closed. In addition, the opening / closing drive unit 31 can not only move the silicone resin 30a up and down, but also move the opening / closing part 30 relative to the pipette nozzle 15.

[0031] The coating section 32 applies a sealing material to the opening or other opening of the microfluidic device to suppress the evaporation of the test liquid injected into the opening. Specifically, the coating section 32 is, for example, a nozzle that discharges a sealing material such as silicone oil into the opening, and a pump 33 applies the sealing material to the opening through this nozzle. The configuration of the coating section 32 is not limited to this; it can also be a mechanism that applies the sealing material to the opening using a brush or the like. The coating drive section 34 moves the coating section 32 to the position of the opening or other opening of the microfluidic device where the sealing material is applied, and drives the pump 33. Figure 1 and Figure 2 The diagram shows a configuration where the coating section 32 is equipped with the same moving mechanism as the pipette nozzle 15. However, the coating section 32 can also be equipped with a different moving mechanism than the pipette nozzle 15, with the coating drive section 34 moving the coating section 32. It should be noted that if the evaporation of the test solution is not a problem, the coating section 32 may not be provided in the test apparatus 100.

[0032] The control unit 50 controls the operation of the test apparatus 100. The control unit 50 includes a processor such as a CPU (Central Processing Unit), and memory such as ROM (Read Only Memory) and RAM (Random Access Memory). The memory stores the control program. The processor controls the operation of the test apparatus 100 by executing the control program. Alternatively, the memory of the control unit 50 may also include an HDD (Hard Disk Drive).

[0033] The control unit 50 controls the motor of the platform drive unit 13 to move the platform 16 in a manner that positions the microfluidic device at a predetermined location. Furthermore, after moving the microfluidic device to the predetermined position, the control unit 50 controls the motor of the pipette nozzle drive unit 12 to move the pipette nozzle 15 to allow the test liquid to drain into the opening of the microfluidic path of the microfluidic device. Next, the control unit 50 controls the opening / closing drive unit 31 to switch the opening / closing state of the opening (second opening) of the microfluidic device. Additionally, the control unit 50 controls the coating drive unit 34 to apply sealing material to the opening of the microfluidic device.

[0034] Specifically, the control unit 50 controls the motor of the pipette nozzle drive unit 12 to move the pipette nozzle 15 to the position of the predetermined test liquid container 5, and controls the pump 14 to draw the test liquid from the front end of the pipette nozzle 12. Then, the control unit 50 controls the motor of the pipette nozzle drive unit 12 to move the pipette nozzle 15 to the opening position of the microfluidic device, and controls the pump 14 to discharge the test liquid from the front end of the pipette nozzle 1.

[0035] The control unit 50 can be connected to a processing unit 200 implemented by a personal computer (PC) or a dedicated computer. The user can manage the testing apparatus 100 via the processing unit 200. For example, the processing unit 200 can set the movement amount of the platform 16 of the platform drive unit 13, the movement amount of the pipette nozzle 15 of the pipette nozzle drive unit 12, and the amount of test liquid drawn or discharged from the tip of the pipette nozzle 1 using the pump 14. The processing unit 200 can also be electrically connected to other devices arranged adjacent to the testing apparatus 100 to form a testing system.

[0036] [The structure of microflow circuit devices]

[0037] Figure 4 This is a diagram illustrating an example of the configuration of the microfluidic device according to this embodiment. Figure 4 The image shows a top view of the microflow device 2. The microflow device 2 is placed on platform 16 of the experimental apparatus 100.

[0038] like Figure 4 As shown, the microfluidic device 2 includes a plate-shaped component 20 and a flow path structure. The flow path structure includes an opening 21, an opening 22 (first opening), a branch flow path 23a, a microfluidic path 23b, a storage section 24, an opening 26 (third opening), a gas permeable membrane 27, a recovery section 28, and an opening 29 (second opening). Alternatively, the microfluidic device 2 may also be configured without the opening 26 (third opening).

[0039] An opening 22 is provided within the opening 21 and is the portion that connects the opening 21 to the branch flow path 23a. That is, the opening 22 is connected to one end of the branch flow path 23a. Test liquid is forced into the branch flow path 23a from the opening 22 using fluid pressure. The test liquid forced into the branch flow path 23a is further forced into the microflow path 23b. In this embodiment, air pressure is used as the fluid pressure. The opening 22 has, for example, a circular cross-section. The diameter of the opening 22 is, for example, 5 μm to 5 mm. In this embodiment, four branch flow paths 23a are connected to the opening 22. The four branch flow paths 23a are arranged radially with the opening 22 as the center.

[0040] In this embodiment, four branch flow paths 23a are connected to the opening 22, but the embodiments of the present invention are not limited to this. It is sufficient to connect at least one branch flow path 23a to the opening 22. Alternatively, two or three branch flow paths 23a may be connected to the opening 22. Furthermore, five or more branch flow paths 23a may be connected to the opening 22.

[0041] The branch flow path 23a extending from the opening 22 further branches into multiple microflow paths 23b. The branch flow path 23a and the multiple microflow paths 23b are connected in a manner that allows the test liquid to flow. The test liquid flowing in from the opening 22 flows through the branch flow path 23a to the branched microflow paths 23b. The cross-section of the branch flow path 23a and the microflow paths 23b is rectangular, and their widths are, for example, 1 μm to 1 mm. However, the depths (heights) of the branch flow path 23a and the microflow paths 23b are different. For example, the depth of the branch flow path 23a is 0.5 mm, while the depth of the microflow path 23b is less than 0.025 mm. Therefore, the flow resistance of the microflow path 23b is greater than that of the branch flow path 23a. Compared to branch flow path 23a, by increasing the flow resistance of microflow path 23b, as described later, the test liquid flowing in from opening 22 can flow in almost simultaneously relative to the multiple microflow paths 23b after temporarily filling branch flow path 23a. Furthermore, in this embodiment, one branch flow path 23a branches into 14 microflow paths 23b.

[0042] The branch flow path 23a is configured along the X-axis direction until it branches into multiple microflow paths 23b. After branching, each microflow path 23b is configured along the Y-axis direction. A storage section 24 is provided midway through each microflow path 23b after branching. Each microflow path 23b allows the test liquid flowing in from the opening 22 to flow in the storage section 24.

[0043] The storage section 24 contains a reagent and is connected to the opening 22 via a branch flow path 23a and a microflow path 23b, storing the test solution flowing in from the opening 22. In the storage section 24, the test solution reacts with the reagent. The reagent is, for example, an antibacterial agent. The reagent can be solid or liquid. The reagent is pre-loaded into the storage section 24. That is, the reagent is placed in the storage section 24 before the test solution flows into it. In this embodiment, the reagent is coated onto the entire storage section 24.

[0044] The storage section 24 is formed in the shape of a cuboid. The length of one side of the storage section 24 is, for example, 10 μm to 10 mm.

[0045] exist Figure 4In this design, 56 (14 x 4) storage compartments 24 are formed in the plate-shaped component 20. The test solution stored in each of the 56 storage compartments 24 has the same capacity. On the other hand, the types and amounts of the reagents placed in the 56 storage compartments 24 can be the same or different from each other.

[0046] A microflow path 23b located between the storage section 24 and the opening 26 is configured to allow the test liquid to flow. This microflow path 23b is arranged along the Y-axis. One end of the microflow path 23b is connected to the storage section 24, and the other end is connected to the opening 26. The microflow path 23b allows the test liquid flowing from the storage section 24 to flow into the opening 26.

[0047] The opening 26 is connected to the other end of the microfluidic path 23b. The opening 26 has a circular cross-section, for example. The diameter of the opening 26 is, for example, 5 μm to 5 mm.

[0048] Opening 26 is covered by gas-permeable membrane 27. Specifically, in Figure 4 In the plate-shaped component 20, 56 (14 x 4) openings 26 are formed. Of the 56 openings 26, 28 openings 26 formed at the positive Y-axis end of the plate-shaped component 20 are covered by a gas-permeable membrane 27, and 28 openings 26 formed at the negative Y-axis end of the plate-shaped component 20 are covered by a gas-permeable membrane 27. The two gas-permeable membranes 27 are respectively arranged along the X-axis direction.

[0049] The gas permeable membrane 27 has the function of allowing gas to pass through but preventing liquid from passing through. Examples of materials for the gas permeable membrane 27 include polytetrafluoroethylene (PTFE). The gas permeable membrane 27 preferably has water-repellent properties. The thickness of the gas permeable membrane 27 is 1 mm or less.

[0050] The gas-permeable membrane 27 is fixed to the plate-shaped component 20 by means of adhesive bonding, ultrasonic welding, etc. Examples of adhesives include photocurable resins, thermocurable resins, and pressure-sensitive resins.

[0051] The recovery section 28 is connected to the end of the branch flow path 23a opposite to the end connected to the opening 22, and is a part of the recovered test liquid. The recovery section 28 is formed in a cuboid shape. The length of one side of the recovery section 28 is, for example, 10 μm to 10 mm. A water-absorbing component such as a sponge may also be provided in the recovery section 28. This prevents backflow from the recovery section 28 to the branch flow path 23a and prevents the evaporation of the test liquid from the branch flow path 23a.

[0052] Opening 29 is connected to the end of recovery section 28 on the opposite side of the end connected to branch flow path 23a. From opening 22 to opening 29, the flow path 23a and recovery section 28 are configured to allow test liquid to flow. Furthermore, opening 29 is closed by being blocked by the silicone resin 30a of opening / closing section 30. By closing opening 29, test liquid flowing into branch flow path 23a is prevented from being discharged into recovery section 28 and opening 29; by opening opening 29, test liquid remaining in branch flow path 23a can be discharged into recovery section 28 and recovered.

[0053] Figure 5 This is a diagram illustrating an example of the flow path configuration for injecting test pressure into the microfluidic device of this embodiment. The plate-shaped component 20 includes... Figure 5 The upper first plate-shaped member 20a and the lower second plate-shaped member 20b. The second plate-shaped member 20b is stacked on top of the first plate-shaped member 20a. The second plate-shaped member 20b is disposed relative to the first plate-shaped member 20a. Figure 4 The negative direction (downward direction) of the Z-axis is shown.

[0054] The first plate-shaped component 20a and the second plate-shaped component 20b are formed into rectangular plates from a transparent material. Examples of materials for the first plate-shaped component 20a and the second plate-shaped component 20b include acrylic resins such as polymethyl methacrylate resin and glass. A flow path structure is formed in the first plate-shaped component 20a. Specifically, the first plate-shaped component 20a has an opening 22, a branch flow path 23a, a microflow path 23b, a storage section 24, an opening 26, and a recovery section 28 (see reference). Figure 4 The second plate-shaped component 20b functions as the lower surface of the opening 22, branch flow path 23a, microflow path 23b, storage section 24, opening 26, and recovery section 28. The thicknesses of the first plate-shaped component 20a and the second plate-shaped component 20b are not particularly limited, and are for example set to 0.5 mm to 3 mm. It should be noted that the second plate-shaped component 20b is directly fixed to the first plate-shaped component 20a by ultrasonic melting, but it can also be fixed by an adhesive.

[0055] In this embodiment, the test liquid drawn in by the pipette nozzle 1 is discharged into the opening 21 of the microfluidic device 2, and the discharged test liquid is pressurized with air pressure and forced into the microfluidic path 23b through the opening 22. To pressurize the test liquid into the microfluidic path 23b, a pressure-in pad (not shown) covering the opening 21 communicating with the microfluidic path 23b can also be provided. However, if a pressure-in pad is provided, and the pressure-in pad is pressed against the opening 21 to apply air pressure and force the test liquid into the microfluidic path 23b, there is a possibility that the test liquid may adhere to the pressure-in pad and become contaminated. Since the pressure-in pad is repeatedly used relative to other microfluidic devices, when measuring other test liquids, there is a possibility that previously measured test liquids may mix in (contaminate) and affect the test results.

[0056] Therefore, a pressure-in pad is prepared that can be installed on the pipette nozzle 1. When the test liquid is pressurized and forced into the microfluidic path 23b, the pressure-in pad covers the opening 21, and air pressure is simultaneously introduced from the pipette nozzle 1. Afterwards, the pressure-in pad and the pipette nozzle 1 can be discarded together. Thus, contamination of the test liquid can be prevented, and highly accurate test results can be obtained.

[0057] like Figure 5 As shown, the test liquid flowing in from the pipette nozzle 1 passes through the opening 22, the branch flow path 23a, and fills the microflow path 23b, the storage section 24, and the opening 26. However, in the microflow device 2, multiple microflow paths 23b are connected via the branch flow path 23a. Therefore, when the test liquid is injected into the microflow device 2, which branches from one opening 22 to multiple microflow paths 23b via the branch flow path 23a, if a difference occurs in the height (hydraulic head) of the liquid surface between each flow path or from the opening 22 to each flow path, flow will occur in the test liquid within each flow path due to this difference.

[0058] Figure 6 This is a diagram showing the state after the test fluid is injected into the flow path of the microfluidic device of this embodiment. Figure 6 The upper path shown is designated as path A, and the lower path as path B. The test liquid flowing in from opening 22 is divided into micro-flow paths 23b of path A and micro-flow paths 23b of path B via branch flow path 23a, and then reaches each opening 26 respectively. For example... Figure 6 As shown, because path B is farther from opening 22 than path A, the hydraulic head of opening 26 in path A is higher than that in path B. Due to the difference in hydraulic head between paths A and B, flow is generated in the test fluid between paths A and B to eliminate this difference. If flow occurs in the storage sections 24 of paths A and B, it may be impossible to observe accurate results.

[0059] Therefore, in this embodiment, after the test fluid is pumped into multiple microflow paths 23b, the test fluid remaining in the branch flow path 23a is discharged to the recovery section 28. By discharging the test fluid remaining in the branch flow path 23a, the multiple microflow paths 23b and the opening 26 are connected via the branch flow path 23a, making each flow path independent and not considered as a single flow path, thus preventing flow caused by hydraulic head difference.

[0060] Figure 7 This is a diagram showing the state after the test liquid is discharged from the branch flow path of the microfluidic device of this embodiment. Figure 7 The upper path shown is designated as path A, and the lower path as path B. Since the test fluid is discharged from branch flow path 23a, the microflow paths 23b of path A and 23b of path B cannot be considered as a single flow path via branch flow path 23a. Therefore, even if the hydraulic head of the opening 26 of path A is higher than that of the opening 26 of path B, no flow of test fluid will occur between path A and path B to eliminate this difference.

[0061] Figure 8 This diagram illustrates a method for discharging test liquid from a branch flow path of the microfluidic device of this embodiment. Figure 8 In this configuration, a plurality of microflow paths 23b are connected to a branch flow path 23a, and a recovery section 28 is connected to one end of the branch flow path 23a. An opening 29 is provided at the end of the recovery section 28 on the opposite side from the end connected to the branch flow path 23a. Although not shown, the branch flow path 23a is connected to the opening 22 at the end opposite to the end connected to the recovery section 28.

[0062] If the test liquid flows into branch flow path 23a, the flow resistance of each microflow path 23b is greater than that of branch flow path 23a. Therefore, unless branch flow path 23a is completely filled with test liquid, the test liquid will not flow into each microflow path 23b. To make the flow resistance of each microflow path 23b greater than that of branch flow path 23a, the cross-sectional area of ​​branch flow path 23a should be larger than that of each microflow path 23b. If the width of branch flow path 23a is the same as the width of each microflow path 23b, then the depth of branch flow path 23a should be greater than the depth of each microflow path 23b. For example, if the depth of branch flow path 23a is set to 0.5 mm, and the depth of each microflow path 23b is set to 0.001 mm, then the cross-sectional area of ​​branch flow path 23a can be 500 times the cross-sectional area of ​​each microflow path 23b.

[0063] When test liquid flows into branch flow path 23a, opening 29 is closed by the silicone resin 30a of opening / closing section 30. Therefore, the test liquid flowing into branch flow path 23a is not discharged to recovery section 28 during this stage. After branch flow path 23a is completely filled with test liquid, as... Figure 8 As shown, the test solution flows into each microfluidic path 23b almost simultaneously. Thus, the test solution flows into each microfluidic path 23b and each storage section 24.

[0064] Next, the silicone resin 30a blocking the opening and closing part 30 of the opening 29 is removed, and air is introduced through the opening 22 with the opening 29 open, thereby... Figure 8 As shown, the test liquid remaining in the branch flow path 23a is discharged to the recovery section 28. Additionally, air introduced through the opening 22 can utilize the air discharged from the pipette nozzle 1 to press in the test liquid. The recovery section 28 has a space (buffer space) to hold the discharged test liquid in the branch flow path 23a, which is larger than the volume of the branch flow path 23a.

[0065] Whether the test liquid in the branch flow path 23a is discharged into the recovery section 28 can be controlled by opening and closing the opening 29. The test liquid remaining in the branch flow path 23a is discharged into the recovery section 28 through the opening 22 by air.

[0066] In this embodiment, test liquid is injected into each microflow path 23b, and after the test liquid remaining in the branch flow path 23a is discharged to the recovery section 28, sealing materials such as silicone oil are applied to the openings 22, 26, and 29. Figure 9 This is a diagram showing the state of the opening of the microfluidic device in this embodiment coated with sealing material. (See diagram for reference.) Figure 9 As shown, silicone oil 33a is applied to openings 22, 26, and 29 in the coating section 32 (refer to...). Figure 8 By coating the openings 22, 26, and 29 with silicone oil 33a, the evaporation of the test liquid from each microfluidic path 23b through the openings 22, 26, and 29 can be suppressed. Furthermore, since a gas-permeable membrane 27 is provided at the opening 26, silicone oil 33a is coated at least at the openings 22 and 29.

[0067] The sealing material applied to openings 22, 26, 29, etc. is not limited to silicone oil 33a. Any material can be used as long as it remains in openings 22, 26, 29, etc. and inhibits the evaporation of the test liquid.

[0068] Next, the pressing method of the test apparatus in this embodiment will be described using a flowchart. Figure 10This is a flowchart illustrating the pressing method of the test apparatus in this embodiment. First, the control unit 50 of the test apparatus 100 controls the motor of the pipette nozzle drive unit 12 to move the pipette nozzle 15 to the position of the predetermined test liquid container 5, and controls the pump 14 to draw the test liquid from the front end of the pipette nozzle 15 into the test liquid container 5 (step S11). The control unit 50 controls the motor of the pipette nozzle drive unit 12 to move the pipette nozzle 15 to the position of the opening 22 of the microfluidic device 2 (step S12).

[0069] Furthermore, the position of the opening / closing part 30 relative to the pipette nozzle 15 is predetermined based on the position of the opening 29 relative to the opening 22 of the microfluidic device 2. Therefore, when the position of the pipette nozzle 15 is matched with the opening 22 of the microfluidic device 2 in step S12, the opening / closing part 30 moves to a position directly above the opening 29. The control unit 50 uses the opening / closing drive unit 31 to move the elastic member (silicone resin 30a) to a position blocking the opening 29 (step S13). The control unit 50 determines whether the opening 29 is closed based on whether the elastic member (silicone resin 30a) is moved to a position blocking all openings 29 (step S14). If it is determined that all openings 29 are not closed (no in step S14), the control unit 50 returns the process to step S13.

[0070] If it is determined that all openings 29 are closed ("Yes" in step S14), the control unit 50 controls the pump 14 to discharge the test liquid from the front end of the pipette nozzle 1 and press the test liquid into the flow path (branch flow path 23a, micro flow path 23b) of the microflow device 2 (step S15).

[0071] The control unit 50 determines whether the test fluid has been injected into the flow paths of all microfluidic devices 2 (step S16). Furthermore, the control unit 50 determines, for example, whether the test fluid has been injected into the flow paths of all microfluidic devices 2 based on the time it took to inject the test fluid into the flow paths of the microfluidic devices 2 and the remaining amount of test fluid in the pipette nozzle 1. If the test fluid has not been injected into the flow paths of all microfluidic devices 2 (not in step S16), the control unit 50 returns the process to step S15.

[0072] When the test liquid is injected into all the flow paths of the microfluidic device 2 (yes in step S16), the control unit 50 uses the opening and closing drive unit 31 to move the elastic member (silicone resin 30a) from the position of the blocked opening 29, opening the opening 29 (step S17). The control unit 50 controls the pump 14 to discharge air from the front end of the pipette nozzle 1, discharging the test liquid remaining in the branch flow path 23a to the recovery unit 28 (step S18).

[0073] The control unit 50 controls the motor of the pipette nozzle drive unit 12 to move the coating unit 32 to the positions of the openings 22, 26, and 29, and applies sealing material to the openings 22, 26, and 29 (step S19).

[0074] [Variation Example]

[0075] (1) In the test apparatus 100 of this embodiment, the opening 29 is closed by blocking the opening 29 with the silicone resin 30a of the opening and closing part 30, but it is not limited to this. As long as the structure switches the opening and closing state of the opening 29, it can be any structure. For example, if the opening 29 of the microflow device 2 is provided with an opening and closing mechanism (gate, etc.), the opening and closing part 30 can also be configured to switch the state of the opening and closing mechanism.

[0076] (2) In the test apparatus 100 of this embodiment, it is described that sealing material is applied to the openings 22, 26, and 29, but it is not limited to this. Any configuration is possible as long as the evaporation of the test liquid can be suppressed. For example, the evaporation of the test liquid can also be suppressed by installing a pre-prepared cover on the openings 22, 26, and 29.

[0077] (3) In the test apparatus 100 of this embodiment, for example, the cross-section of the opening 29 is formed into a circular shape and communicates with the recovery section 28. Therefore, when air is introduced from the opening 22 while the opening 29 is open and the test liquid remaining in the branch flow path 23a is discharged to the recovery section 28, depending on the pressure of the introduced air, not only is the test liquid discharged to the recovery section 28, but there is also a possibility of overflow from the opening 29. Therefore, the opening 29 is covered with a gas permeable membrane. Figure 11A-11C This is a diagram showing the structure of the recovery section and the opening according to a modified example. Figure 11A This is a top view of the portion at the end of a branch flow path 23a connected to multiple microflow paths 23b, where a recovery section 28 is provided. Figure 11B yes Figure 11A A cross-sectional view of the recycling section 28 at the cutting line I shown.

[0078] exist Figure 11B The diagram illustrates a gas-permeable membrane 27a covering opening 29. The gas-permeable membrane 27a can be made of the same material as the gas-permeable membrane 27 covering opening 26, or a different material, as long as it allows gas to pass through while preventing liquid from passing through. Examples of materials for the gas-permeable membrane 27a include polytetrafluoroethylene (PTFE). The gas-permeable membrane 27a preferably has water-repellent properties. The thickness of the gas-permeable membrane 27a is 1 mm or less.

[0079] By covering the opening 29 with the gas permeable membrane 27a, the test liquid remaining in the branch flow path 23a can be prevented from overflowing from the opening 29 when it is discharged to the recovery section 28. In addition, in order to keep the opening 29 closed, the opening 29 needs to be blocked from the gas permeable membrane 27a by the silicone resin 30a of the opening and closing section 30.

[0080] In this way, by further having a gas-permeable membrane 27a covering the opening 29 (the second opening), the risk of the test liquid not remaining in the recovery section 28 and being discharged from the opening 29 can be reduced when the test liquid remaining in the branch flow path 23a is discharged to the recovery section 28.

[0081] exist Figure 11B In this design, an opening 29 is provided at the end of the recovery section 28 opposite to the end connected to the branch flow path 23a. However, by providing an opening within the recovery section 28 itself, a structure without the opening 29 can be achieved. Even in a structure without the opening 29, air must still be introduced through the opening 22 while the opening in the recovery section 28 is open, and the test liquid remaining in the branch flow path 23a must be discharged into the recovery section 28. Therefore, depending on the pressure of the introduced air, not only may the test liquid be discharged into the recovery section 28, but there is also a possibility of overflow from the opening in the recovery section 28.

[0082] Figure 11C yes Figure 11B A modified example of the recovery section 28 is shown. Figure 11C The diagram illustrates an opening 28a formed by completely removing the first plate-shaped member 20a located on the upper surface of the recovery section 28. Furthermore, the opening 28a in the recovery section 28 is covered by a gas-permeable membrane 27b. By providing the opening 28a across the entire upper surface of the recovery section 28, the possibility of the entire gas-permeable membrane 27b coming into contact with the test liquid is eliminated, ensuring that air is always removed from the gas-permeable membrane 27b, facilitating the discharge of all test liquid remaining in the branch flow path 23a. It should be noted that the opening 28a does not need to cover the entire upper surface of the recovery section 28; it can be provided only on at least a portion of the upper surface of the recovery section 28, provided it is sufficiently large relative to the amount of test liquid discharged into the recovery section 28.

[0083] The gas permeable membrane 27b can be made of the same material as the gas permeable membrane 27 covering the opening 26, or it can be made of a different material, as long as it has the function of allowing gas to pass through while preventing liquid from passing through. Examples of materials for the gas permeable membrane 27b include polytetrafluoroethylene (PTFE). The gas permeable membrane 27b preferably has water-repellent properties. The thickness of the gas permeable membrane 27b is 1 mm or less.

[0084] By covering the opening 28a of the recovery section 28 with the gas permeable membrane 27b, the test liquid remaining in the branch flow path 23a can be prevented from overflowing from the opening 28a when it is discharged into the recovery section 28. In addition, in order to keep the opening 28a closed, the entire opening 28a needs to be blocked from the gas permeable membrane 27b by the silicone resin 30a of the opening and closing section 30.

[0085] Thus, the recovery section 28 has an opening 28a in at least a portion and a gas permeable membrane 27b covering the opening 28a, thereby enabling easy discharge of all test liquid remaining in the branch flow path 23a and reducing the risk that the test liquid will not remain in the recovery section 28 but will be discharged from the opening 28a.

[0086] [Way]

[0087] Those skilled in the art will understand that the above-described embodiments are specific examples of the following methods.

[0088] (Item 1)

[0089] One type of testing apparatus is a testing apparatus that uses a microfluidic device to perform a test using a test solution containing a sample. The microfluidic device includes: a first opening for receiving the test solution; multiple branch flow paths communicating with the first opening; multiple microfluidic paths communicating with each branch flow path; a recovery unit disposed at the end opposite to the side of each branch flow path communicating with the first opening, for recovering a portion of the test solution; and a second opening disposed in the recovery unit. The testing apparatus includes: a pressurizing unit connected to the first opening, for applying air pressure to force the test solution into the microfluidic path; an opening / closing unit for switching the opening and closing states of the second opening; and a control unit for controlling the pressurizing unit and the opening / closing unit. The control unit controls the second opening to be closed by the opening / closing unit, and the test solution is forcefully injected into the microfluidic path by the pressurizing unit. After the test solution is forcefully injected into the microfluidic path, the control unit controls the second opening to be opened by the opening / closing unit, and the test solution in the branch flow paths is recovered to the recovery unit by applying air pressure by the pressurizing unit.

[0090] According to the test apparatus described in item 1, the test liquid in the branch flow path can be discharged to the recovery section and recovered, thereby suppressing the flow of the test liquid generated in the flow path and observing the correct results.

[0091] (Item 2)

[0092] In the test apparatus described in item 1, the opening and closing part has a mechanism that controls it to be in a closed state by blocking the second opening with an elastic member.

[0093] According to the test apparatus described in item 2, since the second opening is blocked by an elastic member, the apparatus configuration can be simplified, and the second opening can be easily kept closed.

[0094] (Item 3)

[0095] In the test apparatus described in claim 1, the pressurizing section includes: a pipette for aspirating or discharging test liquid; and a moving mechanism for changing the relative position of the pipette and the microfluidic device, wherein the moving mechanism connects the pipette to the first opening, discharges the aspirated test liquid to the first opening, thereby pressurizing the test liquid into the microfluidic path.

[0096] According to the test apparatus described in item 3, test pressure can be easily injected into each microchannel of the microchannel device.

[0097] (Item 4)

[0098] The test apparatus described in item 1 further includes a coating section for coating a sealing material that inhibits the evaporation of the test liquid, and the microflow device also has a third opening, which is disposed on the downstream side when viewed from the side connected to the branch flow path. The coating section coats the sealing material at least at the first and third openings of the microflow path into which the test liquid is pressed.

[0099] According to the test apparatus described in item 4, the test liquid can be prevented from evaporating from the openings because a sealing material is applied to the first and third openings.

[0100] (Item 5)

[0101] In the test apparatus described in item 4, the sealing material is silicone oil.

[0102] According to the test apparatus described in item 5, since the sealing material is silicone oil, it is easy to apply the sealing material to the opening.

[0103] (Item 6)

[0104] One method of injection involves injecting a test solution containing a sample into a microfluidic device. The microfluidic device has: a first opening for receiving the test solution; multiple branch flow paths communicating with the first opening; multiple microflow paths communicating with each branch flow path; a recovery section disposed at the end opposite to the side of each branch flow path communicating with the first opening, for recovering a portion of the test solution; and a second opening disposed at the recovery section. The injection method includes: closing the second opening; connecting a pipette containing the test solution to the first opening; discharging the aspirated test solution into the first opening to inject the test solution into the microfluidic device; opening the second opening; and applying air pressure from the pipette to recover the test solution from the branch flow paths to the recovery section.

[0105] According to the injection method described in item 6, the test liquid in the branch flow path can be discharged to the recovery section and recovered, thus suppressing the flow of test liquid generated in the flow path and observing the correct results.

[0106] (Item 7)

[0107] In the pressing method described in item 6, the microfluidic device further includes a third opening disposed on the downstream side as viewed from the side communicating with the branch flow path, and also includes a step of applying a sealing material to at least the first and third openings of the microfluidic path in which the test liquid has been pressed in to inhibit the evaporation of the test liquid.

[0108] According to the pressing method described in item 7, since a sealing material is applied to the first and third openings, the test liquid can be prevented from evaporating from the openings.

[0109] (Item 8)

[0110] In the pressing method described in item 7, the sealing material is silicone oil.

[0111] According to the pressing method described in item 8, since the sealing material is silicone oil, it is easy to apply the sealing material to the opening.

[0112] (Item 9)

[0113] One type of microfluidic device is a microfluidic device used in a test using a test solution containing a sample, comprising: a first opening for receiving the test solution; a plurality of branch flow paths communicating with the first opening; a plurality of microflow paths communicating with each of the branch flow paths; a recovery section disposed at the end opposite to the side of each branch flow path communicating with the first opening, for recovering a portion of the test solution; and a second opening disposed at the recovery section.

[0114] According to the microfluidic device described in item 9, the test liquid in the branch flow path can be discharged to the recovery section and recovered, thus suppressing the flow of test liquid generated in the flow path and observing the correct results.

[0115] (Item 10)

[0116] In the microflow device described in item 9, the recovery section is a buffer space that is connected to the end of the branch flow path and is larger in volume than the branch flow path.

[0117] According to the microfluidic device described in item 10, since the recovery section is a buffer space with a volume larger than that of the branch flow path, all the test liquid remaining in the branch flow path can be recovered.

[0118] (Item 11)

[0119] In the microfluidic device described in item 10, a water-absorbing component is provided in the buffer space.

[0120] According to the microflow device described in item 11, backflow from the recovery section to the branch flow path can be prevented, and the evaporation of the test liquid from the branch flow path can be prevented.

[0121] (Item 12)

[0122] In the microflow path device described in item 9, the flow path resistance of the microflow path is greater than the flow path resistance of the branch flow path.

[0123] According to the microflow path device described in item 12, since the flow path resistance of the microflow path is greater than that of the branch flow path, the test liquid in the branch flow path can flow into each microflow path almost simultaneously.

[0124] (Item 13)

[0125] The microfluidic device described in item 9 also includes a gas-permeable membrane covering the second opening.

[0126] According to the microflow path device described in item 13, when the test liquid remaining in the branch flow path is discharged to the recovery section, the risk of the test liquid not remaining in the recovery section but being discharged from the opening can be reduced.

[0127] (Item 14)

[0128] In the microfluidic device described in item 9, the recovery section further comprises a gas-permeable membrane having an opening in at least a portion and covering the opening.

[0129] According to the microflow path device described in item 14, all test liquid remaining in the branch flow path can be easily discharged, and the risk of test liquid not remaining in the recovery section but being discharged from the opening can be reduced.

[0130] The embodiments of the present invention have been described above, but it should be considered that the embodiments disclosed herein are illustrative rather than restrictive in all respects. The scope of the invention is set forth in the claims and is intended to include all modifications within the meaning and scope equivalent to the claims.

Claims

1. A testing apparatus for performing tests using a test solution containing a sample, employing microfluidic devices. The microflow device has the following characteristics: The first opening receives the test solution; One or more branch flow paths, each having one end connected to the first opening and another end opposite to the first opening; Multiple microflow paths are connected to each of the branch flow paths between one end and the other end; A recovery section, located at the other end of each of the branch flow paths, has space for recovering a portion of the test liquid remaining in the branch flow paths; The second opening is located in the recycling section; The third opening is located at the end of multiple microflow paths. The test apparatus includes: a pressurizing section connected to the first opening, which applies air pressure to force the test liquid into the microflow path; The opening and closing part switches the opening and closing state of the second opening; The moving mechanism enables the pressurizing part and the opening / closing part to move horizontally as a whole, and enables the pressurizing part and the opening / closing part to move separately in the direction of gravity; The control unit controls the pressurizing unit, the opening and closing unit, and the moving mechanism. The pressurizing section has a pipette for drawing in or discharging the test solution. The third opening has a space that intersects the extension direction of the microflow path and extends along the direction of gravity. The moving mechanism moves the pipette to the position of the first opening, arranging the pipette and the opening / closing part in a positional relationship such that the opening / closing part is located at the second opening. The control unit causes the pipette to move horizontally towards the first opening and the opening / closing part to move horizontally towards the second opening as a single unit. The system is controlled so that the second opening is closed by the opening and closing part while the third opening is open, and the test fluid is pumped into the microfluidic path by the pipette. After the test liquid is injected into the microfluidic path, the system is controlled to keep the pipette in the position of the first opening and move the opening and closing part in the opposite direction to gravity to open the second opening. Air pressure is applied by the pipette to recover the test liquid remaining in the branch flow path to the recovery part.

2. The test apparatus as described in claim 1, characterized in that, The opening and closing part has a mechanism that controls it to be in a closed state by blocking the second opening with an elastic member.

3. The test apparatus as described in claim 1, characterized in that, The moving mechanism connects the pipette to the first opening, discharges the aspirated test liquid into the first opening, and thus forces the test liquid into the microfluidic path.

4. The test apparatus as described in claim 1, characterized in that, The moving mechanism also includes a coating section for coating a sealing material that inhibits the evaporation of the test liquid. The third opening of the microflow path device, when viewed from the side communicating with the branch flow path, is located on the downstream side. The coating section applies the sealing material to at least the first opening and the third opening of the microfluidic path into which the test liquid is pressed.

5. The test apparatus as described in claim 4, characterized in that, The sealing material is silicone oil.

6. A method for pressing in a test apparatus, comprising pressing a test sample containing a specimen into a microfluidic device. The microfluidic device has: a first opening for receiving the test liquid; One or more branch flow paths, each having one end connected to the first opening and another end opposite to the first opening; Multiple microflow paths are connected to each of the branch flow paths between one end and the other end; a recovery section is provided at the other end of each of the branch flow paths, having a space for recovering a portion of the test liquid remaining in the branch flow paths; a second opening is provided in the recovery section; The test apparatus includes a third opening located at the end of multiple microfluidic paths. The apparatus comprises: a pressurizing unit connected to the first opening, which applies air pressure to inject the test liquid into the microfluidic paths; an opening / closing unit that switches the opening / closing state of the second opening; a moving mechanism capable of moving the pressurizing unit and the opening / closing unit horizontally as a unit, and moving the pressurizing unit and the opening / closing unit separately in the direction of gravity; and a control unit that controls the pressurizing unit, the opening / closing unit, and the moving mechanism. The pressurizing unit has a pipette for aspirating or discharging the test liquid. The third opening has a space that intersects the extension direction of the microfluidic paths and extends in the direction of gravity. The moving mechanism moves the pipette to the position of the first opening, positioning the pipette and the opening / closing unit in a positional relationship similar to that of the second opening. The pressing method of the test apparatus includes: The step of moving the pipette towards the first opening and the opening / closing part towards the second opening in a horizontal manner; The step of closing the second opening by the opening and closing part while the third opening is open; The step of connecting the pipette that has drawn the test solution to the first opening; The step of discharging the aspirated test liquid into the first opening, thereby injecting the test liquid into the microflow path; After injecting the test solution into the microfluidic path, the pipette is held in the position of the first opening and the opening / closing part is moved in the opposite direction to gravity to open the second opening; and The step of applying air pressure through the pipette to recover the test solution remaining in the branch flow path to the recovery section.

7. The pressing method of the test apparatus as described in claim 6, characterized in that, The third opening of the microflow path device, when viewed from the side communicating with the branch flow path, is located on the downstream side. The pressing method further includes the step of applying a sealing material to at least the first opening and the third opening of the microfluidic path through which the test liquid is pressed in, to inhibit the volatilization of the test liquid.

8. The pressing method of the test apparatus as described in claim 7, characterized in that, The sealing material is silicone oil.

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