A flow channel tip and a method for injecting liquid into the flow channel tip.

Abstract

The present invention provides a flow channel tip that can suppress the incorporation of air when injecting liquid into the flow channel. [Solution] A flow channel chip having a path formed for liquid to flow, comprising: a first flow channel formed on a first surface of the flow channel chip; a second flow channel formed on a second surface facing the first surface; a connecting passage connecting the first flow channel and the second flow channel; an inlet for injecting liquid into the first flow channel or the second flow channel; and a connection port for connecting a liquid transfer mechanism for moving the liquid injected into the first flow channel or the second flow channel within the first flow channel or the second flow channel, wherein the inlet is formed in the connecting passage, the shape of the inlet is formed so that the inlet and a liquid injection tool inserted into the inlet come into contact, and when liquid is injected from the inlet with the liquid injection tool, the liquid is injected only into the other of the first flow channel or the second flow channel while one of the first flow channel or the second flow channel is blocked by the liquid injection tool.

Description

[Technical Field]

[0001] The present invention relates to a flow path chip having a liquid flow path formed therein and a method for injecting liquid into the flow path chip. [Background Art]

[0002] Flow path chips are used which enable processing such as measurement and analysis of liquid by forming a flow path on a substrate or the like and injecting liquid into the flow path. In particular, micro flow path chips capable of processing liquid with a small amount of liquid are widely used for analysis in fields such as medicine, the environment, and food. Patent Document 1 discloses a micro flow path chip in which a liquid flow path is formed on a substrate, pump chambers are provided at both ends of the flow path, and the position of the liquid injected into the flow path in the flow path can be adjusted. [Prior Art Literature] [Patent Literature]

[0003] [Patent Document 1] Japanese Unexamined Patent Publication No. 2023-172459 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] If air is mixed in when injecting liquid into a flow path chip, there is a possibility that a problem may occur when conveying the liquid to a desired position in the flow path. Particularly in a micro flow path chip in which pump chambers are formed at both ends of the flow path as described in Patent Document 1, it is necessary to inject liquid from the middle of the flow path rather than from the end of the flow path, so after liquid is injected from the injection port, the liquid inevitably branches to one side and the other side of the flow path. When the liquid branches, the possibility that air is mixed in particularly increases.

[0005] The present invention provides a flow path chip capable of suppressing air mixing when injecting liquid into a flow path. [Means for Solving the Problem]

[0006] The flow channel chip of the present invention is a flow channel chip having a path formed for the flow of liquid, comprising: a first flow channel formed on a first surface of the flow channel chip; a second flow channel formed on a second surface of the flow channel chip facing the first surface; a connecting passage connecting the first flow channel and the second flow channel; an inlet for injecting the liquid into the first flow channel or the second flow channel; and a connection port communicating with the flow channel for connecting a liquid transfer mechanism for moving the liquid injected into the first flow channel or the second flow channel within the first flow channel or the second flow channel, wherein the inlet is formed in the connecting passage, the shape of the inlet is formed so that the inlet and a liquid injection tool inserted into the inlet come into contact, and when the liquid is injected from the inlet with the liquid injection tool, the liquid is injected only into the other of the first flow channel or the second flow channel while one of the first flow channel or the second flow channel is blocked by the liquid injection tool. In the flow channel tip configured as described above, the inlet is formed in a communication passage connecting the first and second surfaces of the flow channel tip, and the shape of the inlet is formed to contact the liquid injector. As a result, when liquid is injected from the inlet, one side of the flow channel is blocked by the liquid injector, and the liquid is injected only into the other side of the flow channel from the inlet.

[0007] In the above configuration, the liquid injection device is a pipette, and the shape of the injection port may be formed to abut against the tip of the pipette. In the flow channel tip configured as described above, the shape of the inlet is formed so that the tip of the pipette comes into contact with the inlet. As a result, when liquid is injected from the inlet, one side of the flow channel is blocked by the pipette.

[0008] In the above configuration, the connection ports may be arranged on opposite sides of the inlet. In the flow channel chip configured as described above, liquid transfer mechanisms are connected to connection ports formed on opposite sides of the inlet, thereby adjusting the position of the liquid within the flow channel by sucking and pushing out the liquid injected into the flow channel from both sides of the inlet.

[0009] In the above configuration, the inlet may be configured to have a circular shape in cross-sectional view, formed such that its diameter gradually increases or decreases from the first flow path to the second flow path. In the flow channel tip configured as described above, the inlet is formed to have a circular shape in cross-section, with the diameter gradually increasing or decreasing toward the flow channel, so that a liquid injector having a similar shape can be brought into contact with the inlet.

[0010] The present invention can also be configured as a method for injecting liquid into a flow channel chip in which a path for liquid flow has been formed. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a flow channel tip that can suppress the mixing of air when a liquid is injected into the flow channel. [Brief explanation of the drawing]

[0012] [Figure 1] This is a perspective view showing an example of a flow channel chip. [Figure 2] Figure 1 is a plan view of the flow channel chip. [Figure 3] This is a cross-sectional view of the flow channel chip cut along line AA in Figure 2. [Figure 4] This is a cross-sectional view showing the process of injecting liquid into the flow channel tip using a pipette. [Modes for carrying out the invention]

[0013] Embodiments of the present invention will be described below with reference to the drawings shown as an example. Figure 1 is a perspective view showing a channel chip 1 as an example of a channel chip. Figure 2 is a plan view of the channel chip 1. Figure 3 is a cross-sectional view of the channel chip 1 cut along line AA in Figure 2. In Figures 1 and 2, the liquid channel formed on the inside or opposite side of the channel chip 1 is shown by a dashed line. The channel chip 1 forms a path for liquid to flow on a substrate. In this embodiment, a microchannel chip that circulates liquid through a microchannel in which at least one of the width or length (depth) of the channel is 1 mm or less will be described as an example. The channel chip 1 is formed of, for example, a resin such as a thermoplastic resin, thermosetting resin, or photocurable resin, glass, or polydimethylsiloxane (PDMS). Examples of thermoplastic resins include polycarbonate, polyethylene, polypropylene, polyvinyl chloride, polyester, acrylic, cycloolefin polymer (COP), and cyclic olefin copolymer (COC). Examples of thermosetting resins include phenolic resin, polyurethane, and thermosetting polyimide. The flow channel chip 1 can be manufactured by various molding methods, such as injection molding.

[0014] The flow channel chip 1 is formed in a flat plate shape having a predetermined thickness. The flat plate shape can also be described as the shape of a rectangular prism. Here, of the six outer surfaces that form the rectangular prism, the two surfaces with the largest area are called the first surface 2 and the second surface 3, respectively. In Figure 1, the first surface 2 forms the bottom surface and the second surface 3 forms the top surface. The second surface 3 can also be described as the surface opposite the first surface 2. On the first surface 2, a first flow channel 10 is formed, recessed to a predetermined depth from the surface of the first surface 2. On the second surface 3, second flow channels 20 and 30 are formed, recessed to a predetermined depth from the surface of the second surface 3. The second flow channel 20, the first flow channel 10, and the second flow channel 30 are formed in a straight line in this order when viewed from above. One end of the second channel 20 and one end of the first channel 10 are formed to overlap in a plan view, and the other end of the first channel 10 and one end of the second channel 30 are formed to overlap in a plan view. Connecting passages 40 and 50 are formed to connect one end of the first channel 10 and one end of the second channel 20, and the other end of the first channel 10 and one end of the second channel 30, respectively. The connecting passages 40 and 50 are circular cross-section holes that penetrate the channel tip 1 in the thickness direction, and the diameter of the holes is formed to gradually increase from the first surface 2 (first channel 10) to the second surface 3 (second channels 20, 30). The openings of the connecting passages 40 and 50 on the second surface 3 side function as inlets for injecting liquid into the first channel 10.

[0015] Connection ports 60 and 70 are formed at the other ends of the second flow channels 20 and 30, respectively. The connection ports 60 and 70 are circular cross-sectional holes that penetrate the flow channel tip 1 in the thickness direction. The connection ports 60 and 70 are formed by a large diameter portion 61 and 71 on the first flow channel 10 side, a small diameter portion 62 and 72 on the second flow channels 20 and 30 side, and flat surfaces 63 and 73 between the large diameter portion 61 and 71 and the small diameter portion 62 and 72. Both the large diameter portion 61 and 71 and the small diameter portion 62 and 72 are formed such that the diameter of the hole gradually decreases from the first surface 2 toward the second surface 3 (second flow channels 20 and 30). The large diameter portion 61 and 71, which are openings on the first surface 2 side of the connection ports 60 and 70, function as a suction device connection port for connecting an air suction machine for sucking up liquid or an extrusion device connection port for connecting an air blower for pushing out liquid. Connection ports 60 and 70 are located on opposite sides of each other, separated by connecting passages 40 and 50, which function as inlets.

[0016] Although not shown in the diagram, the first channel 10 and the second channels 20 and 30 are sealed by joining a cover having a flat surface to the first surface 2 and the second surface 3 of the channel chip 1. Possible types of covers include other channel chips (substrates), films, silicon, etc. For example, it is possible to form a sealed channel by joining another channel chip (substrate) with a flat surface to the surface of the channel chip 1 on which the channel is formed. The method of joining the channel chips (substrates) is not particularly limited, but for example, it is possible to join channel chips (substrates) to each other by heat fusion.

[0017] In the flow channel chip 1 formed as described above, the connection port 60 communicates with the second flow channel 20, the second flow channel 20 communicates with the communication passage 40, the communication passage 40 communicates with the first flow channel 10, the first flow channel 10 communicates with the communication passage 50, the communication passage 50 communicates with the second flow channel 30, and the second flow channel 30 communicates with the connection port 70. In other words, a single connected path is formed from the connection port 60 toward the connection port 70, making two round trips between the first surface 2 and the second surface 3. Liquid is injected into this path, and the position of the liquid within the path is adjusted by applying air to the liquid.

[0018] Hereinafter, a method for injecting a liquid into the flow channel chip 1 will be described. Fig. 4 is a cross-sectional view showing a state where a liquid is injected into the flow channel chip 1 by a pipette P. Fig. 4 shows an example in which a liquid is injected into the flow channel chip 1 using the communication passage 40 as an injection port. Note that reference sign P only illustrates the tip portion of the pipette. The tip portion of the pipette P has a truncated conical shape formed such that the diameter gradually decreases toward the tip. The shapes of the communication passages 40 and 50 are formed to match the shape of the tip portion of the pipette P. When the pipette P is inserted into the communication passage 40 from above, the outer circumference of the tip portion of the pipette P abuts against the inner circumference of the communication passage 40 over the entire circumference. Thereby, the second flow channel 20 is blocked by the pipette P. When a liquid is injected from the pipette P in this state, as indicated by the arrows in Fig. 4, the liquid does not flow into the second flow channel 20, but flows only into the first flow channel 10.

[0019] After injecting the liquid, the pipette P is removed from the communication passage 40. A cover is previously bonded to the first surface 2, and the cover is bonded to the second surface 3 after removing the pipette P. By bonding covers to the first surface 2 and the second surface 3 respectively, the flow channel chip 1 with a liquid injected into the flow channels is completed. In this state, an unillustrated air suction device or air blower is connected to the connection ports 60 and 70. The position of the liquid injected into the first flow channel 10 is adjusted by the air suction device or the air blower. For example, an air blower is connected to both the connection port 60 and the connection port 70, and the liquid injected into the flow channel is pushed out by the air blower, thereby adjusting the position of the liquid in the flow channel.

[0020] As described above, in the flow channel chip 1 of the present invention, the tip of the pipette P is brought into contact with the communication path 40, and in a state where the second flow channel 20 is blocked by the pipette P, the liquid is injected only into the first flow channel 10 from the pipette P. The liquid is injected only into the first flow channel 10 formed on the first surface 2 side, and does not flow into the second flow channel 20 formed on the second surface 3. Since the injected liquid does not branch, air entrainment between liquids can be suppressed. By suppressing air entrainment, accurate measurement and analysis of the liquid can be achieved. Further, when the liquid injected into the flow channel is conveyed by an air suction device or an air blower, the liquid can be conveyed to a desired position in the flow channel without being obstructed by the entrained air.

[0021] In the above embodiment, a micro flow channel chip having micro flow channels in which at least one of the vertical width or the horizontal width of the flow channel is 1 mm or less has been described as an example, but the flow channel width is not necessarily limited to 1 mm or less. The present invention is also applicable to flow channel chips having a flow channel width exceeding 1 mm.

[0022] In the above embodiment, the exemplified material, molding method, and bonding method between substrates of the flow channel chip are merely examples. As long as it has the flow channel shape shown in the above embodiment, the effect of the present invention can be exhibited regardless of the material of the substrate or the like.

[0023] In the above embodiment, an example in which the first flow channel 10 and the second flow channels 20, 30 are formed linearly in a plan view has been described, but the shape of the flow channel is not limited thereto. The first flow channel and the second flow channel may form complicatedly intertwined flow channels on a plane. Further, a flow channel that reciprocates between the first surface 2 and the second surface 3 a plurality of times may be formed. In that case, at least one of the communication paths that communicate the first surface 2 and the second surface 3 may function as an injection port.

[0024] In the above embodiment, an example was described in which the communication passage 40 is used as the inlet. Similarly, it is also possible to use the communication passage 50 as the inlet. By forming the inlet in the communication passage between the first surface 2 and the second surface 3, it is possible to configure the system to inject liquid only into the other of the first or second flow path while blocking one of the first or second flow path. In the above embodiment, a flow path chip with two communication passages, the communication passage 40 and the communication passage 50, was described as an example, but the present invention can be applied to any flow path chip in which at least one communication passage between the first surface 2 and the second surface 3 is formed.

[0025] In the above embodiment, an example was described in which pipette P is used as a liquid injection device for injecting liquid into the flow path. A micropipette capable of injecting small amounts of liquid, such as a few μL to several hundred μL, with high precision is preferably used as pipette P. It is also possible to use pipette P with a single-use (disposable) pipette tip attached to its tip. In addition to pipettes, droppers, syringes, dispensers, etc., can also be used as liquid injection devices. Micropipettes can be used when injecting specimens, nucleic acid samples, protein samples, cell suspensions, etc. Droppers, on the other hand, are suitable for easily injecting relatively large volumes of liquid and can be used when injecting washing solutions, culture media, buffers, etc. The flow path tip of the present invention has an injection port shape that can accommodate multiple types of liquid injection devices such as micropipettes and droppers, and the appropriate liquid injection device can be selected and used depending on the type of liquid used, the injection volume, the required precision, or the application. Furthermore, the fluid channel tip of the present invention can be suitably used as a single-use (disposable) fluid channel tip that is replaced after each analysis, thereby suppressing contamination between samples.

[0026] In the above embodiment, an example was described in which an air blower is connected to both connection port 60 and connection port 70 as a means of transporting the liquid injected into the flow path to a desired position. It is also possible to connect an air suction machine instead of an air blower to both connection port 60 and connection port 70 to suction the liquid. Air blowers and air suction machines are examples of liquid transport means, but the liquid transport means are not limited to these. Other means can be used as long as they can transport the liquid under pressure. Connection ports are formed at both ends of the flow path, and the liquid transport means only needs to be connected to the connection port formed at least at one end of the flow path. If the liquid transport means is connected to only one end of the connection port, the other end of the connection port also functions as a vent. In addition, in the above embodiment, an example was described in which the connection ports 60 and connection port 70 are formed on the first surface 2, but the connection ports may also be provided on the second surface 3. A filter may be installed between the connection port and the liquid transport means to prevent foreign matter from entering.

[0027] It goes without saying that the present invention is not limited to the embodiments described above. It goes without saying that those skilled in the art will understand this, - Apply the mutually interchangeable members and configurations disclosed in the above embodiments by appropriately changing their combinations. • Although not disclosed in the above embodiments, it is possible to appropriately substitute and modify the combinations of publicly known components and components that are interchangeable with those disclosed in the above embodiments. • Although not disclosed in the above embodiments, the members and components that a person skilled in the art could conceive of as substitutes for those members and components disclosed in the above embodiments based on prior art, etc., may be appropriately substituted, and their combinations may be modified for application. This is disclosed as one embodiment of the present invention. [Explanation of Symbols]

[0028] 1...flow channel tip, 2...first surface, 3...second surface, 10...first flow channel, 20...second flow channel, 30...second flow channel, 40...connecting passage, 50...connecting passage, 60...connecting port, 61...large diameter section, 62...small diameter section, 63...flat surface, 70...connecting port, 71...large diameter section, 72...small diameter section, 73...flat surface.

Claims

1. A channel chip in which a path for liquid to flow is formed, A first channel formed on the first surface of the channel tip, A second flow channel is formed on the second surface of the flow channel chip facing the first surface, A connecting passage that connects the first flow path and the second flow path, An inlet for injecting the liquid into the first or second flow path, It has a connection port communicating with the flow path for connecting a liquid transfer mechanism for moving the liquid injected into the first flow path or the second flow path within the first flow path or the second flow path, The inlet is formed in the communication passage, The shape of the inlet is formed such that the inlet and the liquid injector inserted into the inlet come into contact with each other. A flow channel tip characterized in that, when the liquid is injected from the inlet using the liquid injection device, the liquid is injected only into the other of the first or second flow channel while one of the first or second flow channels is blocked by the liquid injection device.

2. The aforementioned liquid injection device is a pipette, The flow channel tip according to claim 1, characterized in that the shape of the injection port is formed to contact the tip of the pipette.

3. The flow path chip according to claim 1, characterized in that the connection ports are arranged on opposite sides of the injection port.

4. The flow channel tip according to claim 1, characterized in that the injection port has a circular shape in cross-sectional view, formed such that its diameter gradually increases or decreases from the first flow channel to the second flow channel.

5. A method for injecting liquid into a channel chip in which a path for liquid flow has been formed, A step of injecting the liquid into only one of the first or second flow paths from an inlet formed in a communication passage that connects a first flow path formed on the first surface of the flow path tip and a second flow path formed on the second surface of the flow path tip facing the first surface; The process includes connecting a liquid transfer mechanism to a connection port communicating with the flow path, and moving the liquid injected into the first or second flow path within the first or second flow path. The shape of the inlet is formed such that the inlet and the liquid injector inserted into the inlet come into contact with each other. A method for injecting liquid into a flow channel tip, characterized in that when injecting the liquid from the inlet into either the first flow channel or the second flow channel, the liquid injection device is configured to inject the liquid while blocking the other of the first or second flow channel.

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