JP5545255B2 - Microchip and manufacturing method thereof - Google Patents

Description

  The present invention relates to a microchip having a fine channel structure that synthesizes and analyzes a microfluidic sample using a fine channel and a reaction vessel. Such a microchip is used as a microfluidic device applied as μTAS (Micro Total Analysis System), microreactor, Bio-MEMS or biochip. In this specification, such small fluid elements are collectively referred to as a microchip.

  In fields such as μTAS and Bio-MEMS, PDMS (polydimethylsiloxane) which is a kind of silicone resin is often used as a material for forming a microchip (see Patent Documents 1 and 2 and Non-Patent Document 1). ). There are several reasons why PDMS is preferred. For example, since PDMS is a transparent resin, the internal state can be observed from the outside when a microchip having a flow path and a reaction vessel is formed inside. PDMS can be easily molded by a casting method or an injection molding method, and a fine structure of several μm or less can be formed. Furthermore, since PDMS is self-adsorbing and not only for PDMS but also for glass, when assembling microchips between PDMS members or a combination of PDMS members and glass members, an adhesive is used. It can be mentioned that it is unnecessary.

  Many microchips using PDMS are manufactured by bonding a PDMS member having a fine channel structure and a PDMS member or glass member to be a lid. The bonding of these members is activated by exposing the surfaces of the members to be exposed to oxygen plasma or by irradiating with ultraviolet rays, and then the activated surfaces are closely adhered to each other and allowed to stand for a certain period of time. It is done by.

  As a mechanism of this bonding, a PDMS surface having a (—Si—O—) group or a glass surface is activated and brought into close contact, so that the surfaces of both members are composed of (—Si—O—Si—) siloxane bonds. It is believed that a strong bond is obtained by the occurrence of a covalent bond called Such a feature is not limited to PDMS, but is common to silicone resins having a (—Si—O—) group.

  However, this bonding method is effective only between members in which a covalent bond called a siloxane bond is generated by activating the bonding surface of the member with oxygen plasma or the like. Even if PDMS is used as one member, the other member to be joined to it has, for example, a (—Si—O—) group like a synthetic resin such as polypropylene that can form a fine structure at low cost by injection molding. When a non-silicone resin material or metal material is used, a siloxane bond cannot be formed, so that even if the bonding surface is treated with oxygen plasma or ultraviolet light, a strong bonding strength cannot be obtained.

  FIG. 7 shows an example of a microchip manufactured by bonding members made of, for example, a silicone resin and polypropylene. In this example, a silicone resin is used as the flow path plate 1 in which a groove serving as a flow path is formed, and polypropylene is used as the base plate 2 to be joined thereto. In the flow path plate 1, three grooves that become the fine flow paths 3 are formed, and holes 4 and 5 penetrating the flow path plate 1 are formed at both ends of each flow path 3. When the surface of the flow channel plate 1 on the side where the groove to be the flow channel 3 is formed and the surface of the base plate 2 are activated by oxygen plasma or the like and bonded together, the microchip of FIG. 7 is obtained. However, since the bonding strength between the silicone resin of the flow path plate 1 and the polypropylene of the base plate 2 is not sufficiently high, in this microchip, when a fluid sample is pressurized and introduced into a plurality of flow paths 3, There is a possibility that separation occurs between the flow path plate 1 and the base plate 2 due to the pressure, and fluid samples between the flow paths 3 are mixed with each other to cause cross contamination.

Instead of using a glass substrate as a member to be combined with a member made of PDMS, it is bonded to a PDMS member so that it can be firmly bonded to the PDMS member even when used as a resin substrate other than a silicone resin. It has been proposed to form a silicon oxide (SiO ₂ ) film on the surface of a resin substrate (see Patent Document 3). The silicon oxide film is formed by a vapor deposition method such as a vacuum deposition method, an ion plating method, a sputtering method, an atmospheric pressure CVD method, a low pressure CVD method, and a plasma CVD method.

JP 2000-27813 A JP 2001-157855 A JP 2005-257283 A

Anal. Chem. 1998, 70, 4974-4984

  The method of forming a silicon oxide film on the surface of a resin substrate other than PDMS to be bonded to the PDMS member increases the manufacturing cost because the silicon oxide film must be formed by a vapor deposition method such as a vacuum evaporation method. .

  Therefore, the present invention provides a microchip capable of obtaining strong bonding strength by a simple method even when a member to be bonded to a member made of silicone resin is a member made of a material other than silicone resin, and a method for manufacturing the microchip. It is intended to provide.

  The microchip of the present invention is configured by joining a flow path plate made of silicone resin to the surface of a base plate made of a material other than silicone resin via a silicone resin coating layer. The flow path plate is a molded product in which a groove serving as a flow path is formed on the joint surface with the silicone resin coating layer, whereby the groove and the groove are formed on the joint surface between the flow path plate and the silicone resin coating layer. A flow path having an inner surface made of a silicone resin coating layer surrounded by a silicone resin is formed. The base plate or the flow path plate is formed with at least one through hole connected to the flow path including the groove.

  In the microchip of the present invention, since the bonding between the flow path plate and the silicone resin coating layer is the bonding of the silicone resins, a sufficient bonding strength can be obtained. Also, between the base plate made of a material other than the silicone resin coating layer and the silicone resin, it is higher than when the flow channel plate surface and the base plate surface made of a material other than the silicone resin are activated and joined by oxygen plasma or ultraviolet irradiation. Bonding strength can be obtained.

  The reason for this is that the liquid silicone resin is applied on the base plate and then cured more than the case where the cured silicone resin is adhered to the base plate made of a material other than the silicone resin. It is mentioned that the adhesiveness is high. It is considered that the liquid silicone resin enters fine irregularities on the surface of the base plate material and is cured in that state, so that high adhesion can be obtained.

  The flow path is formed between the flow path plate and the silicone resin coating layer, and since there is a high bonding strength between the flow path plate and the silicone resin coating layer, peeling between members constituting the flow path is unlikely to occur. Cross contamination is unlikely to occur.

  All the inner walls of the flow path of the microchip of the present invention are formed of silicone resin. A similar structure can be formed by bonding silicone resin members together. However, since silicone resins are generally expensive, the microchip of the present invention using a material other than silicone resin for the base plate is inexpensive and has an equivalent structure. Can be formed.

  A microchip includes a microchip having only a flow path therein. The microchip having only such a flow path includes a microchip having a separation flow path for electrophoresis, a microchip for analysis such as a microchip constituting a liquid chromatograph, and a branching or merging. It can be used as a liquid feed control microchip for controlling the liquid.

  The microchip includes a microchip including a recess in addition to the flow path. The recess can be used for various applications such as a reaction chamber and a cell culture chamber. Unlike the fine irregularities on the surface of the base plate material, the concave portion is used as a reaction chamber, a cell culture chamber, or the like having a size that is about the same as or larger than the width of the flow path. Examples of the microchip provided with the recess include microchips used for inspection and reaction. The concave part of the microchip is connected to the flow path of the flow path plate, and the bottom and side surfaces inside the concave part have portions where the material of the base plate is exposed without being covered with the silicone resin coating layer. It can comprise so that the upper part of a recessed part may be covered with the silicone resin of the flow-path plate.

  In a microchip having a recess, there is a portion where the base plate material is exposed inside the recess, and therefore there is a boundary between the base plate material and the silicone resin coating layer at the opening edge of the recess. Since the bonding strength with the coating layer is also strong, there is little risk of cross-contamination from the interface.

  Having a portion where the material of the base plate is exposed on the inner bottom surface and side surface of the recess of the base plate plays an important role when this microchip is a microchip used for inspection or reaction. In such a microchip, a substance used for a test or reaction performed using the microchip is held in advance in a portion where the material of the base plate inside the recess is exposed. In such a microchip, an inspection probe or a reaction or synthesis substance is held in advance in a concave portion of a base plate, and then joined to a flow path plate to form a microchip. An example of such a test is gene polymorphism detection, and in the microchip in that case, probes that emit fluorescence corresponding to each of a plurality of polymorphic sites are individually held in the recesses of the base plate. In other microchips for biochemical examination or chemical reaction or chemical synthesis, reaction reagents according to measurement items, reactants for chemical reaction or chemical synthesis are held in the recesses of the base plate in advance, and then the flow path Bonded with the plate to form a microchip.

  As described above, when any treatment is performed on the concave portion of the base plate in advance, it is important that the inner surface of the concave portion of the base plate is not covered in the subsequent process. This can be realized only by joining the base plate and the flow path plate with the silicone resin coating layer. As introduced as a proposed prior art, in a method of forming a silicon oxide film on the surface of a resin substrate to be bonded to a PDMS member by a vapor deposition method such as a vacuum deposition method, something is previously formed in a recess of a base plate. Even if the treatment is performed, the silicon oxide film formed by the vapor phase growth method covers the entire inner surface of the concave portion of the base plate, so the microchip in which the substance used for the inspection or reaction is held in the concave portion of the base plate in advance. Cannot be realized.

  Silicone resin is a high molecular compound having a main skeleton with siloxane bonds, and PDMS is an example. In the present invention, the silicone resin is not limited to PDMS, and any silicone resin may be used. For example, a silicone resin in which the methyl group on the side chain of PDMS is substituted with fluorine can be used. Since any silicone resin can form a siloxane bond, the object of the present invention can be achieved.

  As the material of the base plate, non-silicone resin such as polypropylene, fluororesin, polystyrene, or polyolefin copolymer can be used. Of these, polypropylene is particularly useful because it is easy to mold into a fine structure and is an inexpensive material.

  As another material of the base plate, a metal such as a stainless alloy or an aluminum alloy can also be used.

  In the microchip manufacturing method of the present invention, a silicone resin member is bonded to a surface of a pace plate made of a material other than silicone resin with a silicone resin coating layer interposed.

The first embodiment of the microchip manufacturing method includes the following steps.
(A) It is composed of a base plate made of a material other than silicone resin, and a flow channel plate which is a molded product made of silicone resin and having a groove serving as a flow channel on one surface. Preparing a base plate and a flow path plate in which at least one through hole to be connected is formed in the base plate or the plate;

  (B) a step of applying a silicone resin liquid on the surface of the base plate to form a silicone resin coating layer;

  (C) a step of curing the formed silicone resin coating layer,

  (D) A step of activating one or both of the surface of the cured silicone resin coating layer and the surface on which the groove serving as the flow path of the flow path plate is formed by exposure to oxygen plasma or irradiation with ultraviolet light. , And

  (E) Then, the process of sticking together the surface of the silicone resin coating layer and the surface on which the groove to be the flow path of the flow path plate is formed.

The second embodiment of the microchip manufacturing method includes the following steps.
(A) It is composed of a base plate made of a material other than silicone resin, and a flow channel plate which is a molded product made of silicone resin and having a groove serving as a flow channel on one surface. Preparing a base plate and a flow path plate in which at least one through hole to be connected is formed in the base plate or the plate;

  (B) a step of applying a silicone resin liquid on the surface of the base plate to form a silicone resin coating layer;

  (C) A step of bringing the surface of the silicone resin coating layer into close contact with the surface on which the groove serving as the flow path of the flow path plate is adhered before the silicone resin coating layer is cured.

  The state before the silicone resin coating layer is cured means that the silicone resin coating layer and the flow path plate made of the silicone resin are used without performing the activation treatment of the step (D) in the first embodiment of the microchip manufacturing method. It means that the silicone resin coating layer is in an uncured state to such an extent that it can be firmly bonded if left in contact. For example, when using a two-component mixed silicone resin, a state within a pot life (a time during which the main agent and the curing agent are mixed and then cured with the progress of the reaction) is preferable.

  According to the microchip manufacturing method of the present invention, since the silicone resin layer is formed by the coating process, when the concave portion is provided on the surface of the base plate on which the silicone resin coating layer is formed, the silicone resin coating layer is formed only on the surface of the base plate. The silicone resin coating layer is not formed in the recess. In the concave portion on the surface of the base plate after becoming a microchip, there is a portion where the material of the base plate is left exposed. Therefore, this microchip manufacturing method is particularly useful when an inspection probe, a reaction reagent, a reaction product, or the like is held in advance in the recess of the base plate. In vapor phase growth methods such as vapor deposition, it is difficult to perform selective film formation that forms a film only on the surface of the base plate and does not form a film on the recess.

A preferred example of the coating step (B) is:
(B1) including a step of applying a silicone resin liquid in a thin layer having a uniform thickness on a flat surface of a member other than the base plate; and (B2) a step of transferring the applied silicone resin thin layer to the surface of the base plate. It is a process.

  In this preferred coating process, the silicone resin coating layer is formed by coating a silicone resin liquid in a thin layer with a uniform thickness on a flat surface, so that a recess is provided on the surface of the base plate on which the silicone resin coating layer is formed. Even if it is, the film thickness of the silicone resin coating layer can be made uniform.

  The microchip of the present invention is formed by bonding a flow path plate made of silicone resin to a surface of a base plate made of a material other than silicone resin through a silicone resin coating layer, so that it has a fine structure. Therefore, a microchip can be easily produced at a low cost by combining an easy-to-use silicone resin and another member.

  The inner wall of the channel of the formed microchip is formed only of silicone resin. In a field such as μTAS, a fine flow path is often used, and in this case, the flow of fluid in the flow path is strongly influenced by the physical characteristics of the inner wall of the flow path. For example, when the flow path inner wall is formed from a plurality of materials, the physical characteristics of both must be taken into account, making the design difficult. On the other hand, in the microchip of the present invention, since the inner wall of the flow path is formed only of the silicone resin, an easy device design is possible.

  Further, in the microchip of the present invention, since the flow path is sealed with the silicone member and the silicone thin film, even when the silicone thin film is peeled off at the interface between the base plate member, the sealing of the flow path portion is maintained. The possibility of cross contamination can be greatly reduced.

  In the case where the same structure is formed using only a silicone resin, the manufacturing cost increases because the silicone resin is an expensive resin material. Moreover, since a silicone resin is an elastic body, the rigidity as a device cannot be maintained. In the microchip of the present invention, since the material of the base plate can be freely selected, it is easy to increase the rigidity of the device.

  The production method of the present invention is a method of forming a silicone resin coating layer by applying a silicone resin liquid on the surface of a member made of a material other than a silicone resin, or by transferring after coating. Compared to a method of forming a silicon oxide film, this is a simple and low-cost manufacturing method.

  Moreover, compared with the manufacturing method which joins the conventional silicone resin members, the application process of a silicone resin liquid only increases as a process. Even if the coating process further includes a transfer process, such a coating process can be easily realized by existing techniques. The cost increase due to the increase in the coating process is not large, and the cost advantage of replacing the base plate with a material other than the silicone resin material is much greater.

It is a figure which shows the microchip of 1st Example, (A) is a horizontal sectional view, (B) is a vertical sectional view, (A) is sectional drawing in the YY 'line position of (B). (B) is sectional drawing in the XX 'line position of (A). It is a figure which shows the microchip of 2nd Example, (A) is a horizontal sectional view, (B) is a vertical sectional view, (A) is sectional drawing in the YY 'line position of (B). (B) is sectional drawing in the XX 'line position of (A). It is the figure which showed the manufacturing method of the microchip of the 2nd Example in order of a process, (A) is sectional drawing, (B) is a front view, (C) And (D) is sectional drawing. It is a top view which shows the flow-path plate for the microchip for a comparative experiment. It is the schematic which shows a comparative experiment method. It is a graph of the comparison experiment result about the activation process by plasma. These are the graphs of the comparative experiment result about the activation process by an ultraviolet-ray. It is a graph of the comparative experiment result of the Example which joined the Sylgard 184 (brand name) application layer as a silicone resin application layer in the state before drying, and the comparative example which performed the activation process by plasma. It is a graph of the comparative experiment result of the Example which joined the SIFEL8570 (trademark) application layer as a silicone resin application layer in the state before drying, and the comparative example which performed the activation process by plasma. It is a figure which shows the microchip manufactured based on a prior art, (A) is a horizontal sectional view, (B) is a vertical sectional view, (A) is the BB 'line position of (B). Sectional drawing and (B) are sectional drawings in the AA 'line position of (A).

FIG. 1 shows a first embodiment of a microchip. This embodiment is a microchip having only a flow path.
The base plate 10 is made of a material other than silicone resin. In this embodiment, polypropylene is used as the material of the base plate 10. On the surface of the base plate 10, a flow path plate 14 made of silicone resin is bonded via a silicone resin coating layer 12. PDMS is used as a silicone resin for the material of the coating layer 12 and the flow path plate 14.

  The flow path plate 14 is a molded product, and a groove serving as the flow path 16 and two through holes 18 and 20 connected to each groove are formed on the joint surface with the silicone resin coating layer 12. The through hole 18 is a liquid inlet, and the through hole 20 is a liquid outlet. The flow path 16 is formed on the joint surface between the flow path plate 14 and the silicone resin coating layer 12, and is composed of the groove of the flow path plate 14 and the silicone resin coating layer 12, and the inner surface is surrounded by the silicone resin. Yes.

  The microchip includes three flow paths, but the number of flow paths is not limited.

  Such a linear flow path can be used as a flow path for electrophoresis or a separation column for a liquid chromatograph. Here, a microchip having only a linear flow path is shown as the simplest example, but a microchip having a branched flow path for branching and merging can be similarly configured.

The microchip of this embodiment can be manufactured as follows.
(A) A flow that is a molded article in which a flat base plate 10 made of polypropylene, a groove made of PDMS, which becomes a flow path 16 on one surface, and through holes 18 and 20 connected to the other surface from the groove are formed. A road plate 14 is prepared. The grooves and through holes of the flow path plate 14 are formed at the time of molding such as a casting method.

  (B) A PDMS liquid is applied as a silicone resin liquid to the surface of the base plate 10 to form a silicone resin coating layer 12. As the PDMS solution, Sylgard 184 (a trade name of Dow Corning) is used and applied to a thickness of about 10 to 50 μm. The application method is not particularly limited, and application can be performed using a roller, a brush, or the like. Also, a coating layer by transfer may be formed by the method of FIG. 3 described as the manufacturing method of the second embodiment.

  Since the flow path is formed between the groove of the flow path plate 14 and the surface of the silicone resin coating layer 12, the dimensions in the flow path do not change even if the thickness of the silicone resin coating layer 12 changes. Therefore, it is not necessary to strictly control the thickness of the silicone resin coating layer 12.

  (C) The formed silicone resin coating layer 12 is cured. Curing is performed by heating. The heating and curing conditions are, for example, heating for 2 hours in an oven at 85 ° C.

  (D) A surface treatment is performed in order to activate the surface of the cured silicone resin coating layer 12 and the surface on which the grooves serving as the flow paths of the flow path plate 14 are formed. As an activation method, ultraviolet irradiation is performed. For ultraviolet irradiation, an ultraviolet light source (for example, a UV excimer light source (wavelength 172 nm) manufactured by USHIO ELECTRIC CO., LTD.) Is used to irradiate the surface to be activated with ultraviolet light for 2 minutes.

  As the activation treatment, exposure to oxygen plasma may be performed instead of ultraviolet irradiation. Here, both the surface of the silicone resin coating layer 12 and the surface of the flow path plate 14 are activated, but only one of them may be activated. Although only one of the activation treatments is inferior in bonding strength to both activation treatments, a certain degree of bonding strength can be obtained. It can also be activated.

  (E) Thereafter, the surfaces of both activated members are immediately brought into close contact with each other and left to be joined to form a microchip.

FIG. 2 shows a second embodiment of the microchip.
This microchip has a recess formed as a reaction chamber in addition to the flow path. Compared with the embodiment of FIG. 1, the difference is that a recess 22 is formed on the surface of the base plate in the middle of each flow path 16, and the other configuration is the same as that of FIG. Polypropylene is used as the material of the base plate 10a, and PDMS is used as the silicone resin of the silicone resin coating layer 12 and the flow path plate 14.

  The recess 22 formed on the surface of the base plate 10a is connected to the flow path 16 made of PDMS. The inner bottom surface and side surface of the recess 22 are not covered with the PDMS of the silicone resin coating layer 12, and the upper portion of the recess 22 is covered with the PDMS of the flow path plate 14.

  The recess 22 can be left exposed by the polypropylene that is the material of the base plate 10a. In this case, the microchip can be used as a chip for chemical reaction, chemical synthesis, cell culture, etc., and the reaction reagent, cells, and cell culture solution required for the recess 22 through the flow path 16 from the through hole 18 or 20. And so on.

  When this microchip is used as a biochemical reaction test or reaction chip, a test probe and a reaction reagent are held on the inner surface of the recess 22 before joining the flow path plate 14 to the base plate 10a. Necessary processing can be performed in advance. In the microchip of the present invention, even when the flow path plate 14 is joined to the base plate 10a by the silicone resin coating layer 12, the inner surface of the recess 22 is not covered with the silicone resin coating layer 12 but the material of the base plate 10a is exposed. Therefore, the inner surface treatment of the concave portion 22 becomes possible.

FIG. 3 shows a method for manufacturing the microchip of the embodiment of FIG.
(A) A base plate 10a made of polypropylene, a flow channel plate 14 which is a molded product in which a groove made of PDMS and forming a flow channel 16 on one surface and through holes 18 and 20 connected to the other surface from the groove are formed. Prepare. The base plate 10a has a flat plate shape, and a recess 22 is formed on the surface joined to the flow path plate 14 by molding or the like.

  A coating plate 30 is prepared. A concave portion 32 for forming a silicone resin coating layer is formed on the surface of the coating plate 30. The recess 32 has a flat bottom surface and a uniform depth. The depth of the recess 32 is about four times the thickness of the silicone resin coating layer to be formed. For example, the depth is 50 μm. The material of the coating plate 30 is not particularly limited, but is preferably made of a metal such as stainless steel because the bottom surface is flat and the concave portion 32 having a uniform depth can be formed and used repeatedly.

  A silicone resin liquid is applied to the recess 32 of the coating plate 30. For example, Sylgard 184 (trade name) made of PDMS is used as the silicone resin liquid. As a coating method, a silicone resin liquid is dropped into the recess 32, and flattened using a squeegee or the like so that the silicone resin liquid just fills the recess 32. Thereby, the silicone resin coating layer 12 having a thickness of 50 μm equal to the depth of the recess 32 is formed.

  (B) The coating roller 36 is rolled onto the uncured silicone resin coating layer 12, and the silicone resin coating layer 12 is transferred to the coating roller 36. The material of the roller 36 is not particularly limited, but is made of polyurethane, for example. Thereby, about half of the silicone resin coating layer 12 is transferred to the surface of the roller 36.

  (C) The silicone resin coating layer 12 transferred to the coating roller 36 is transferred to the surface of the base plate 10a where the recess 22 is formed. By this step, the silicone resin coating layer 12 is transferred only to the surface other than the concave portion 22 of the base plate base plate 10a. At this time, about half of the silicone resin coating layer 12 on the surface of the roller 36 is transferred to the surface of the base plate 10a.

  (D) The silicone resin coating layer 12 on the base plate 34 is heated and cured. The heat curing condition is, for example, heating for 2 hours in an oven at 85 ° C.

  Thereafter, in order to activate the surface of the flow path plate 14 and the surface of the silicone resin coating layer 12 to be joined to each other, activation is performed using an ultraviolet light source (for example, a UV excimer light source (wavelength 172 nm) manufactured by USHIO). Irradiate the surface to be irradiated with ultraviolet rays for 2 minutes.

  Also in this embodiment, the activation treatment may be performed by exposure to oxygen plasma instead of ultraviolet irradiation, and the activation may be performed not only on both surfaces to be joined but only on one of the surfaces.

  Thereafter, the surfaces of both activated members are immediately brought into close contact with each other and left to join to form a microchip.

  This manufacturing method assumes the embodiment of FIG. 2, but can also be applied to the embodiment of FIG.

  The microchip manufacturing method of the embodiment of FIGS. 1 and 2 has been described above in which the silicone resin coating layer is cured and the bonding surfaces of the members to be bonded are activated by plasma or ultraviolet light, and then both members are brought into close contact with each other It is the method of making it join.

  On the other hand, as another manufacturing method, before the silicone resin coating layer is cured, the surface of the silicone resin coating layer and the surface on which the groove serving as the flow path of the flow path plate is closely adhered are left to stand. The manufacturing method to be performed is also included in the manufacturing method of the present invention. In this case, activation processing by plasma or ultraviolet rays is not performed.

  The measurement results comparing the bonding strength when the silicone resin coating layer is formed and not formed according to the present invention will be described.

  The microchip used in the comparative experiment is a base plate made of polypropylene as in the embodiment shown in FIG. 1, and the flow path plate 14 includes grooves for the flow path 16 as shown in FIG. It consists of PDMS in which one through-hole 18 connected to the groove is formed. The channel plate 14 has a rectangular shape with an outer shape of 80 mm × 25 mm. The groove for the channel 16 has a width of 500 μm, a depth of 400 μm, a length of 60 mm, and a width of about 2 mm on both sides of the linear channel 16a. It has a shape in which twelve oval concave portions 16b having a length of about 3 mm are connected. The depth of the recess 16b is also 400 μm, the same as the depth of the flow path 16a.

  The peeling experiment shown in FIG. 5 was performed using the microchip 40 using the flow path plate 14 of FIG. A pipe 44 is connected to the through hole 18 of the microchip 40 from a pressure controller 42 including a blower, and air pressure is applied to the flow path 16 in the microchip 40 to measure the pressure when air leaks from the microchip 40. did.

  6A to 6D show the measurement results. “PP direct” on the left side is a comparative example, “with PDMS thin layer”, “Sylgard adhesion” or “SIFEL adhesion” on the right side is an example.

  FIG. 6A shows both surfaces to be joined as an activation treatment exposed to oxygen plasma. The activation conditions using oxygen plasma are an oxygen flow rate of 50 sccm, a pressure of 150 mTorr, an applied power of 50 W, and a processing time of 20 seconds. In the examples, “with PDMS thin layer” is obtained by forming a Sylgard 184 (trade name) coating layer made of PDMS as a silicone resin coating layer, curing it, and performing an activation treatment. The same activation treatment was performed in the comparative example.

  FIG. 6B shows a case where both surfaces to be joined as an activation treatment are irradiated with ultraviolet rays. The conditions for activation by ultraviolet rays are as shown in the production methods of the examples. In the examples, “with PDMS thin layer” is obtained by forming a Sylgard 184 (trade name) coating layer made of PDMS as a silicone resin coating layer, curing it, and performing an activation treatment. The same activation treatment was performed in the comparative example.

  In the example of FIG. 6C, a Sylgard 184 (trade name) coating layer made of PDMS was formed as a silicone resin coating layer, and the layers were adhered and bonded before curing. In this case, activation by oxygen plasma or ultraviolet rays is not performed. In the comparative example, activation by the same oxygen plasma as in FIG. 6A was performed.

  In the example of FIG. 6D, a liquid fluorine-based elastomer SIFEL8570 (registered trademark) coating layer was formed as a silicone resin coating layer, and was adhered and bonded before it was cured. Also in this case, activation by oxygen plasma or ultraviolet rays is not performed. In the comparative example, activation by the same oxygen plasma as in FIG. 6A was performed.

  According to this comparative experiment, when a PDMS member is bonded to a polypropylene member, the bonding strength is increased by 5 times or more by interposing a PDMS coating layer, and the bonding strength is increased by about 3 times when a liquid fluorine-based elastomer coating layer is interposed. You can see that

  1 and 2, the two through holes 18 and 20 connected to the flow path 16 are formed in the flow path plate 14, but in the present invention, the through holes 18 and 20 are formed in the base plate 10. It may be formed.

10, 10a Base plate 12 Silicone resin coating layer 14 Channel plate 16 Channel 18, 20 Through hole 22 Recess

Claims (8)

A flow path plate made of silicone resin is joined to the surface of a base plate made of a material other than silicone resin through a silicone resin coating layer.
The flow path plate is a molded product in which a groove serving as a flow path is formed on the joint surface with the silicone resin coating layer,
At least one through hole connected to the flow path consisting of the groove is formed in the base plate or the flow path plate,
A flow path in which an inner surface composed of the groove and the silicone resin coating layer is surrounded by a silicone resin is formed on a joint surface between the flow path plate and the silicone resin coating layer ,
A recess is formed on the surface of the base plate,
The recess is connected to the flow path, and the base plate material is not covered with the silicone resin coating layer on the inner bottom surface and side surface of the recess, so that a substance used for inspection or reaction can be held. A microchip having a portion, and the upper portion of the recess is covered with a silicone resin of the flow path plate . This microchip is a microchip used for inspection or reaction,
The microchip according to claim 1 , wherein a substance used for a test or a reaction performed using the microchip is held in advance in a portion where the material of the base plate is exposed inside the recess. . The microchip according to claim 1 or 2 , wherein the material of the base plate is a non-silicone resin selected from the group consisting of polypropylene, fluororesin, polystyrene, and a polyolefin copolymer. The microchip according to claim 1 or 2 , wherein a material of the base plate is a metal made of a stainless alloy or an aluminum alloy. A method for producing a microchip according to claim 1, comprising the following steps :
(A) a base plate made of a material other than silicone resin, and a flow path plate that is a molded product made of silicone resin and having a flow path groove formed on one surface thereof, and when the two plates are joined together wherein at least one through hole leading to channel formed by the groove is formed in the base plate or channel plate, a recess at the position leading to the flow path when in said base plate the both plates are joined Preparing a formed base plate and a flow path plate;
(B) a step of applying a silicone resin liquid on the surface of the base plate to form a silicone resin coating layer;
(C) curing the silicone resin coating layer,
(D) Activated by exposing one or both of the cured surface of the silicone resin coating layer and the surface of the flow path plate where the groove serving as the flow path is formed to oxygen plasma or by irradiating ultraviolet rays And (E) after that, the step of adhering the surface of the silicone resin coating layer and the surface of the flow path plate where the groove serving as the flow path is formed are bonded together ,
The step (B)
(B1) applying a silicone resin liquid in a thin layer with a uniform thickness on a flat surface of a member other than the base plate; and
(B2) Step of transferring the applied silicone resin thin layer to the surface of the base plate
Manufacturing method . A method for producing a microchip according to claim 1, comprising the following steps :
(A) When a base plate made of a material other than silicone resin and a flow path plate which is a molded product formed of silicone resin and having a flow path on one surface formed thereon, the two plates are joined. wherein at least one through hole leading to channel formed by the groove is formed in the base plate or channel plate, a recess at the position leading to the flow path when in said base plate the both plates are joined Preparing a formed base plate and a flow path plate;
(B) a step of applying a silicone resin liquid on the surface of the base plate to form a silicone resin coating layer;
(C) before the silicone resin coating layer is cured , including a step of adhering and bonding the surface of the silicone resin coating layer and the surface of the flow channel plate where the groove serving as the flow channel is formed ;
The step (B)
(B1) applying a silicone resin liquid in a thin layer with a uniform thickness on a flat surface of a member other than the base plate; and
(B2) Step of transferring the applied silicone resin thin layer to the surface of the base plate
Manufacturing method . The method for manufacturing a microchip according to claim 5 or 6 , wherein in the step of preparing the base plate in the step (A), a recess is formed on the surface of the base plate on which the silicone resin coating layer is formed. This microchip is used for inspection or reaction,
8. The method of manufacturing a microchip according to claim 7 , wherein in the step of preparing the base plate in the step (A), a substance used for inspection or reaction is held inside the recess.

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