Pore device

Abstract

To provide a pore device that is less prone to bonding failures or breakage during lamination or when in use.SOLUTION: A pore device includes: a holding plate 16 with a cavity 12 that houses a pore chip 13; and an upstream plate 14 and a downstream plate 15 that sandwich the holding plate 16. The upstream plate 14, the downstream plate 15, or the holding plate 16 is provided with a groove 23 that connects the cavity 12 with the outside.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a pore device used for the purpose of detecting and analyzing viruses, bacteria, proteins, and DNA by electrophoresis. [Background technology]

[0002] In recent years, nanopores have been used to analyze particles such as viruses, bacteria, proteins, and DNA (see, for example, Patent Document 1). A nanopore is a minute hole with a diameter of several μm to several nm provided in a membrane, and flow paths are connected to both sides of the nanopore. A liquid containing particles, etc. is passed through one flow path, and a liquid not containing particles, etc. is filled in the other flow path, and appropriate different electric potentials are applied between the two flow paths. Then, the liquid containing particles, etc. introduced from one flow path passes through the nanopore and flows out into the other flow path, at which time a change occurs in the electric potential. By observing this change, the characteristics of the particles, etc. can be analyzed.

[0003] For ease of use, nanopores are configured as a device called a nanopore device. A nanopore device mainly consists of a nanopore chip and two flow path plates that sandwich it from above and below. The nanopore is provided in the membrane of the nanopore chip, and an inlet is provided on one surface of the nanopore chip and an outlet is provided on the other surface. Each of the two flow path plates has a fine flow path through which a liquid flows, and when the nanopore chip is sandwiched between the two flow path plates, each flow path is connected to the inlet and outlet of the nanopore chip, respectively. In general, a minute hole in a membrane with a diameter of micron order is called a micropore, and a minute hole with a diameter of nanon order is called a nanopore, but since the terms are not strictly distinguished, in the following explanation, both are collectively called a pore.

[0004] A more specific example of the configuration of the pore device will be described with reference to FIG. 1. The pore chip 61 (FIG. 1(c)) is composed of a substrate 62 made of silicon or SiO2, and a membrane 63 made of silicon nitride (Si3N4) provided on one side of the substrate. The membrane 63, which is 20 to 50 nm thick, has minute holes (pores) 64 with diameters of several μm to several nm. The pore chip 61 is generally configured to reinforce such a thin membrane 63 by integrating it with the substrate 62. The pore chip 61 is accommodated in a cavity 52 of a module body 53 (FIGS. 1(a) and (b)) that has a cavity 52 for accommodating the pore chip 61. The module body 53 is roughly composed of an upper flow path plate 54, a lower flow path plate 55, and a holding plate 56 that is sandwiched between them, has a cavity 52, and has the same height as the pore chip 51. The upstream flow path plate 54 is composed of two plates, with the lower plate (pore chip side) having an upstream flow path 57, and the other plate (upper side) having a vertical flow path 58 connecting the upstream flow path 57 to the surface of the module body 53. The downstream flow path plate 55 is similarly composed of two plates, with the upper plate (pore chip side) having a downstream flow path 59. The vertical flow path 60 connecting the downstream flow path 59 to the surface of the module body 53 is provided so as to penetrate the holding plate 56 and the upstream flow path plate 54.

[0005] The module body 53 of the pore device is produced by stacking a plurality of plate materials as described above, and each plate material must be stacked closely, without any gaps between them. The plate material for the module body 53 is preferably a material that is transparent so that the inside can be observed, and is also chemically and mechanically strong, and cycloolefin polymer (COP) is suitable as such a material. As a method for tightly bonding COP plates, the applicant of the present application has proposed bonding the COP plates after subjecting them to water plasma treatment (Patent Documents 2 and 3). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2020-046314 A [Patent Document 2] JP 2020-011403 A [Patent Document 3] JP 2022-190586 A [Patent Document 4] JP 2020-011304 A [Patent Document 5] JP 2020-085578 A (paragraph number 0041) [Patent Document 6] International Publication No. 2019 / 008736 (Paragraph No. 0034) Summary of the Invention [Problem to be solved by the invention]

[0007] When manufacturing a pore device, a pore chip is inserted into the cavity of a holding plate, and the top and bottom of the pore chip are sandwiched between the upper and lower flow plates to stack them. During this process, the air in the cavity may not be able to escape and may remain in the cavity under high pressure. In particular, when stacking pore devices under reduced pressure and heated atmosphere to exhaust the small amount of air remaining between the holding plate and both flow plates, the air in the cavity expands, which may cause excessive force to be applied to the stacked parts of the pore device, resulting in poor bonding or damage. The air inside may also expand during use. In these cases, excessive force may be applied to the stacked parts of the pore device, resulting in poor bonding or damage.

[0008] The present invention has been made to solve such problems, and its object is to provide a pore device that does not suffer from poor bonding or damage during stacking or use. [Means for solving the problem]

[0009] The present invention, which has been made to solve the above problems, is a pore device that includes a retaining plate having a cavity for accommodating a pore chip, and an upstream flow path plate and a downstream flow path plate that sandwich the retaining plate, and is characterized in that a groove is provided in the upstream flow path plate, downstream flow path plate or retaining plate to connect the cavity to the outside.

[0010] The pore device is constructed by placing a pore chip in a cavity of a holding plate included in the pore device and sandwiching it between an upper flow path plate and a lower flow path plate. In the pore device according to the present invention, at least one of the upper flow path plate, the lower flow path plate, and the holding plate is provided with a groove (relief groove) that connects the cavity with the outside of the pore device. Effect of the Invention

[0011] In the pore device according to the present invention, the upstream flow plate, downstream flow plate, or holding plate is provided with a groove (relief groove) that connects the cavity to the outside, so that when the pore chip is accommodated in the cavity and the upstream flow plate, downstream flow plate, and holding plate are densely stacked, the air in the cavity can escape to the outside through the relief groove. Even if the air in the cavity expands during use, the air can escape to the outside through the relief groove. As a result, the pore device according to the present invention does not suffer from poor bonding or damage during manufacture (when stacking the components such as the upstream flow plate, downstream flow plate, and holding plate) or during use. [Brief description of the drawings]

[0012] [Figure 1] Plan view (a), cross-sectional view (b) of the module body of a conventional pore device, and enlarged cross-sectional view (c) of the pore tip. [Diagram 2] FIG. 2A is a plan view of a pore device using a module body according to one embodiment of the present invention, FIG. 2B is a perspective cross-sectional view of the plan view taken along the bb plane, and FIG. 2C is a cross-sectional view of the plan view taken along the cc plane. [Diagram 3] FIG. 2 is a plan view of unit plates L1 to L10 constituting an upstream flow path plate, a holding plate, and a downstream flow path plate of a module body according to one embodiment of the present invention. [Figure 4] FIG. 13 is a plan view of unit plates cL1 to cL10 that constitute the module body of the comparative pore device. [Diagram 5] 1 is a flow chart of a method for manufacturing a pore device. [Figure 6] Photographs (a) and (b) of a pore device including an embodiment of the present invention and a comparative pore device taken from above, and enlarged photographs (c) and (d) of the pore tip portion viewed from below of each pore device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] FIG. 2(a) shows a plan view of a pore device using a module according to one embodiment of the present invention, and FIG. 2(b) shows a bb-plane perspective cross-sectional view of the plan view. For ease of explanation, the internal flow paths and passages are shown in the bb-plane perspective cross-sectional view in the drawing with appropriate forward and backward movements. FIG. 2(c) shows a cc-plane cross-sectional view of the plan view of FIG. 2(a). Note that the holes and protrusions for alignment and pressurization mentioned in FIG. 3 are omitted in FIG. 2.

[0014] This pore device 10 is composed of a module body 11 and a pore chip 13 housed in a cavity 12 formed inside the module body 11. The pore device 10 as a whole is a plate-like shape with a planar shape of approximately 25×25 mm and a thickness of approximately 1 mm. The pore chip 13 is a plate-like shape with a planar shape of approximately 5×5 mm and a thickness of 0.4 mm. Therefore, in Figures 2(b) and (c), it is shown enlarged in the thickness direction.

[0015] The module body 11 is constructed by stacking 10 unit plates, of which the top three (L1, L2, L3) constitute the upper flow path plate 14, the bottom three (L8, L9, L10) constitute the lower flow path plate 15, and the middle four (L4, L5, L6, L7) constitute the holding plate 16. The cavity 12 is formed in the holding plate 16. The upper flow path 17 is formed in the upper flow path plate 14, and the lower flow path 18 is formed in the lower flow path plate 15. The upper flow path 17 and the lower flow path 18 are formed so as to flow above and below the pore chip 13 inside the pore device 10, respectively, and are formed so as to cross the pore chip 13 at an intersection while being at different upper and lower positions. In both the upper flow path 17 and the lower flow path 18, introduction paths 19, 20, 21, and 22 running vertically through the module body 11 are formed at both ends of each flow path 17, 18 so as to open to the top surface of the pore device 10. Holes 31, 32 for connecting the upper and lower flow paths 17, 18 to the upper and lower openings of the pore chip 13 in the cavity are provided in the lowest unit plate L3 of the upper flow path plate 14 and the uppermost unit plate L8 of the lower flow path plate 15, respectively.

[0016] In the module body 11 of this embodiment, a clearance groove 23 connecting the cavity 15 to the outside of the pore device 10 is formed in the unit plate L3 of the upstream flow path plate 14 that contacts the holding plate 16.

[0017] FIG. 3 shows a plan view of the unit plates L1 to L10 constituting the upper flow path plate 14, the holding plate 16, and the lower flow path plate 15. The unit plates L1 to L3 constitute the upper flow path plate 14, the unit plates L4 to L7 constitute the holding plate 16, and the unit plates L8 to L10 constitute the lower flow path plate 15. Among these, the unit plate L2 has an upper flow path 17, the unit plate L3 has an escape groove 23, the unit plates L4 to L7 have cavities 12, and the unit plate L9 has a lower flow path 18. The unit plates L3 and L8 have holes 31 and 32 that communicate the upper flow path with the pore chip, respectively. The holes provided on both sides of all the unit plates L1 to L10 are provided for alignment when all the unit plates L1 to L10 are stacked. Moreover, the protrusions provided on both edges of the unit plates L1 to L10 are provided for the convenience of handling when the unit plates L1 to L10 are stacked.

[0018] For comparison, a plan view of unit plates cL1 to cL10 constituting a module body without an escape groove is shown in Fig. 4. Unit plate cL3 has no escape groove, and is otherwise the same as unit plates L1, L2, and L4 to L10 in Fig. 3. A pore device using this module body is called a comparative pore device.

[0019] The manufacturing method of the pore device 10 (and the comparative pore device) is as follows (FIG. 5). First, the unit plates L1 to L10 are cut out from a sheet as a material (S1). A COP film can be used as the sheet as a material. A cutting machine can be used for cutting out the unit plates. Next, the unit plates L1 to L10 are subjected to a plasma surface treatment using water (H20) as a plasma gas to make the surfaces hydrophilic (S2). In the manufacturing method of the pore device of this embodiment, the plasma surface treatment may be performed under atmospheric pressure or under reduced pressure, but it is preferable to perform the treatment under reduced pressure because the hydrophilic treatment can be performed without being affected by nitrogen in the atmosphere and the like, and sterilization treatment can be performed simultaneously with the hydrophilic treatment (see, for example, Patent Document 4). The plasma surface treatment using water (H20) as a plasma gas under reduced pressure can be performed, for example, using AQ-2000 (product name) manufactured by Samco Co., Ltd. The plasma conditions can be, for example, as follows. Process gas: H2O (water vapor) Flow rate: 12 sccm Pressure: Approx. 7 Pa High frequency power: 50 W Processing time: 80 seconds The preferred high frequency power is 10 to 400 W / 1200 cm 2 The preferable pressure in the plasma processing chamber is 1 to 200 Pa, the preferable amount of water vapor introduced into the plasma processing chamber is 2 to 50 sccm, and the preferable processing time is 2 to 600 sec. In order to strengthen the bonding between the unit plates L1 to L10, it is preferable to immerse the hydrophilized unit plates L1 to L10 in an adsorbent liquid (e.g., an aqueous solution of aminopropylmethoxysilane), remove them from the adsorbent liquid, wash them with water, and dry them, thereby coating the surfaces of the unit plates L1 to L10 with the adsorbent (S3). When applying plasma surface treatment to the 10 unit plates L1 to L10, the plasma surface treatment may be applied to each unit plate in sequence, or, for example, the plasma surface treatment may be applied to all unit plates arranged on a carrier tray, or the plasma surface treatment may be applied to a sheet material and then the unit plates may be cut out using a cutting machine, so that the plasma surface treatment may be applied to multiple unit plates at the same time. In addition, the plasma surface treatment may be applied to both sides of the unit plates or sheets at the same time. By applying plasma surface treatment to both sides of the unit plates or sheets at the same time, the bonding strength can be further improved and the treatment time can be shortened. When the treatment is applied to a sheet, the process in FIG. 5 is performed with S2 first and S1 last.

[0020] The unit plates L1 to L10 are stacked while being aligned using the alignment holes (at this time, the pore tip is inserted into the cavity 12) (S4), and a force is applied from above and below the 10 stacked unit plates (pressurizing step, S5). This completes the pore device. The unit plates L1 to L10 can be aligned, for example, by passing a positioning pin through the alignment holes. The pressurizing step is desirably performed under a reduced pressure and heated atmosphere, so that the minute amount of air remaining between the unit plates L1 to L10 can be exhausted. The reduced pressure and heated atmosphere can have a pressure of about 0.1 to 10 kPa, a temperature of about 60 to 160°C, a loading pressure of about 0.1 to 5 MPa, and a loading time of about 0.1 to 60 min.

[0021] The pressurization may be performed at once after all ten unit plates L1 to L10 are laminated, or the unit plates L4 to L7 of the holding plate 16 are laminated, the pore chip is inserted into the cavity, and the unit plates L3 and L8 are laminated above and below it, and then the first pressurization is performed, and then the unit plates L1, L2, L9, and L10 are laminated above and below it, and the second pressurization is performed on the whole. In this case, the first pressurization is performed because the unit plates L3 and L8 are each a single film and are flexible, so that the film follows the shape of the pore chip 13 to improve adhesion, or the lamination of L3, L8, the pore chip, and the holding plate can be strengthened by pressing without passing through the space of the upper and lower flow paths. In addition, in order to strengthen the bond between the pore chip and the upper and lower unit plates L3 and L8, it is preferable to perform plasma surface treatment on the pore chip as well.

[0022] It is known that the effect of plasma surface treatment (hydrophilicity and bonding strength) decreases over time in membranes made of COP films and silicon nitride (Si3N4). Therefore, the manufacturing method of the pore device of this embodiment preferably includes a step of maintaining and recovering the hydrophilicity of the pore device by immersing the pore device 10 in an aqueous solution after treating it with oxygen plasma, performing plasma surface treatment using oxygen as plasma gas under atmospheric pressure or reduced pressure immediately before flowing a liquid containing particles or the like into the flow path of the pore device 10 (see, for example, Patent Documents 5 and 6), or performing ultraviolet irradiation. This step is not particularly limited as long as it can maintain and recover the hydrophilicity of the pore device, but plasma surface treatment under reduced pressure is more preferable in that the plasma gas can easily flow into and diffuse into the flow path and the membrane and flow path can be sufficiently treated. Furthermore, this step is more preferable in that the plasma surface treatment using water as plasma gas can be simultaneously performed to hydrophilize and sterilize the membrane and flow path. This step is effective not only for the pore device of this embodiment but also for the pore device of the comparative example.

[0023] Photographs of the pore device 10 including the embodiment of the present invention and the comparative pore device thus manufactured are shown in Figs. 6(a) and (b) taken from the top. The pore device 10 (Fig. 6(a)) is almost transparent over the entire surface, and all unit plates L1 to L10 appear to be neatly joined, but the comparative pore device (Fig. 6(b)) has white areas around the cavities, suggesting that they are not completely joined. In addition, enlarged photographs of the pore chip portion seen from the bottom of the pore device are shown in Figs. 6(c) and (d). No defects are seen in the pore device 10 including the embodiment of the present invention (Fig. 6(c)), but white areas are seen around the pores in the comparative pore device (Fig. 6(d)), suggesting that the pore chip (membrane) is damaged. In the pore device 10, the escape groove 23 is thought to prevent excessive load from being applied to the pore chip.

[0024] In the above embodiment, the escape groove 23 is provided in the unit plate L3 directly above the cavity 12, but it may be provided in the unit plate L8 directly below, or in the unit plates L4 and L7 that form the cavity 12. Two or more of these may be provided at the same time. The direction of the escape groove 23 is arbitrary, and it does not have to be a straight line. In other words, it is sufficient that the escape groove 23 is provided so that the pressure in the cavity 12 and the pressure outside the pore device are the same.

[0025] In the above embodiment, all the unit plates are cut out from one COP sheet, but the flow path plate and the holding plate may be cut out from different plate materials. In that case, the holding plate can be cut out from one thick plate material. Also, the unit plates L1 and L2 can be cut out from one thick plate material, and the introduction channels 19, 20, 21, 22 and the upstream flow path 17 can be provided to create the upstream flow path plate. In this case, the holding plate, which is a single thick plate material, and the upstream flow path plate (L1 and L2), which is also a single thick plate material, are laminated via the unit plate L3, which is a flexible film, so that the adhesion with the pore chip 13 is further improved. [Explanation of symbols]

[0026] 10…Pore device 11, 53...Module body 12, 52…Cavity 13, 51…Pore tip 14, 54...Upstream road board 15, 55...Downstream road plate 16, 56...retention plate 17, 57...Upstream route 18, 59...downstream path 19, 20, 21, 22, 58, 60...Introduction path 23...Relief groove

Claims

1. A pore device comprising a retaining plate having a cavity for accommodating a pore chip, and an upstream flow path plate and a downstream flow path plate sandwiching the retaining plate, characterized in that a groove is provided in the upstream flow path plate, downstream flow path plate or retaining plate connecting the cavity to the outside.

2. The pore device according to claim 1 , wherein the groove is provided in the upstream flow plate.

3. The pore device according to claim 1 , wherein the retaining plate, the upstream flow path plate and the downstream flow path plate are made of COP.

4. The pore device according to claim 1 , wherein the upstream flow path plate and the downstream flow path plate each consist of a flow path plate having a flow path and a flat plate having no flow path.

5. The pore device of claim 1 , wherein the retaining plate comprises a plurality of plates.

6. a plasma surface treatment process for hydrophilizing the mutual bonding surfaces of the holding plate, the upstream flow path plate, and the downstream flow path plate, each of which has a groove on one of the bonding surfaces, with water plasma; an adhesion preparation step of coating the surfaces of the support plate, the upstream flow path plate, and the downstream flow path plate that have been subjected to the surface treatment step with an adsorbent; A chip accommodating step of accommodating a pore chip in the cavity of the holding plate that has undergone the bonding preparation step; a pressurizing step in which the upper and lower sides of the holding plate containing the pore chip are sandwiched between the upper flow path plate and the lower flow path plate that have been subjected to the bonding preparation step, and pressure is applied; A method for producing a pore device comprising:

7. A method for producing a pore device as described in claim 6, comprising a step of treating the pore device with plasma using oxygen or water as a raw material.

Images