JP5196132B2 - Microchip - Google Patents

Description

  The present invention relates to a microchip useful as a micro-TAS (Micro Total Analysis System) suitably used for biochemical tests such as DNA, proteins, cells, immunity and blood, chemical synthesis, and environmental analysis. Relates to a microchip with a built-in liquid reagent, in which a liquid reagent for mixing or reacting with a sample to be tested or analyzed is previously incorporated in the microchip.

  In recent years, the importance of detecting, detecting or quantifying biological substances such as DNA (Deoxyribo Nucleic Acid), enzymes, antigens, antibodies, proteins, viruses and cells, and chemical substances in fields such as medicine, health, food, and drug discovery There have been proposed various biochips and microchemical chips (hereinafter collectively referred to as microchips) that can be easily measured. Microchips can perform a series of experiments and analysis operations performed in the laboratory within a chip of several centimeters square and several millimeters in thickness. However, it has many advantages such as being able to perform high-throughput, high-throughput testing, and obtaining test results immediately at the site where the sample is collected, and is suitably used for biochemical tests such as blood tests.

  The microchip usually has a fluid circuit inside thereof, and the fluid circuit is used to measure the sample introduced into the fluid circuit, to mix the sample (for example, blood, etc.) and the reagent. Various fluid treatments are performed. Such fluid treatment can be performed by applying a centrifugal force in an appropriate direction to the microchip.

  Among the microchips described above, the liquid reagent built-in microchip is a microchip in which a liquid reagent for mixing or reacting with a sample or a specific component in the sample is held in advance in the fluid circuit. One or a plurality of liquid reagent holding units for holding the liquid reagent are provided (see, for example, Patent Document 1 for a microchip having a liquid reagent holding unit). In addition, one or more reagent injection ports penetrating to the liquid reagent holding part for injecting the liquid reagent into the liquid reagent holding part are formed on one surface of the liquid reagent containing microchip. The reagent inlet is sealed by, for example, applying a sealing label (seal) or the like to the microchip surface after the liquid reagent is injected.

Here, when injecting the liquid reagent into the liquid reagent holding part, the injected liquid reagent flows backward through the reagent inlet and overflows on the microchip surface, or the liquid reagent partially scatters, Liquid reagent droplets may adhere on top. Such leakage or scattering of the liquid reagent hinders good adhesion between the sealing label (seal) and the microchip surface, and in this case, the liquid reagent may not be sealed with good sealing performance. . It is difficult to visually check the leakage and scattering of the liquid reagent on the surface of the microchip when the liquid reagent is injected, and when such leakage or scattering of the liquid reagent occurs, recognize this, At present, it is difficult to prevent the outflow of defective products.
JP 2007-285792 A

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a microchip capable of easily visually confirming the presence or absence of a liquid adhering to the surface.

  In the present invention, at least a first substrate having a groove on the surface and a second substrate are bonded so that a groove forming side surface of the first substrate faces the second substrate. Provided is a microchip having a fluid circuit therein, in which fine irregularities are formed on at least a part of the surface of the microchip.

  In one embodiment of the present invention, the microchip includes a liquid reagent holding unit for holding a liquid reagent that forms part of the fluid circuit, and a liquid reagent in the liquid reagent holding unit formed on the surface of the microchip. And a reagent injection port for injecting the liquid, and fine irregularities are formed around the reagent injection port.

  In another embodiment of the present invention, the microchip has a liquid reagent holding part for holding a liquid reagent that constitutes a part of the fluid circuit, and a liquid reagent holding part formed on the surface of the microchip. A reagent inlet for injecting a liquid reagent and a recess formed on the surface of the microchip so as to surround the reagent inlet, on the surface of the microchip positioned between the reagent inlet and the recess Fine irregularities are formed on the surface.

  In the present invention, the microchip bonds the first substrate having the groove on the surface and the second substrate so that the groove forming side surface of the first substrate faces the second substrate. When the first substrate is a transparent substrate, the fine irregularities are on the surface of the first substrate opposite to the surface facing the second substrate, and grooves are formed. It is preferable to be formed in part or all of the region. At this time, it is preferable that the fine unevenness is not formed in the surface region of the first substrate facing the surface region in contact with the second substrate.

  The microchip of the present invention may be configured by bonding a third substrate, a first substrate having grooves on both surfaces, and a second substrate in this order. In this case, the fine unevenness is on the surface of the second substrate or the third substrate opposite to the surface facing the first substrate, and in a part or all of the region where the groove is formed. Preferably it is formed. In this case, when the second substrate and the third substrate are transparent substrates, the fine unevenness is a surface region facing the surface region in contact with the first substrate in the second substrate or the third substrate. Preferably, it is not formed.

  The height of the fine irregularities is preferably in the range of 0.1 to 10 μm.

  According to the microchip of the present invention, the presence or absence of liquid such as a liquid reagent attached on the surface of the microchip can be easily confirmed visually or with an image recognition device such as a CCD camera. Therefore, a microchip with a sealing label (seal) having good adhesion between the microchip surface and a sealing label (seal) for sealing the reagent inlet can be efficiently produced.

  The microchip of the present invention is a chip capable of performing various chemical synthesis, inspection / analysis, and the like using a fluid circuit included in the microchip. In one preferred embodiment, the microchip includes a first substrate having grooves on the substrate surface, The second substrate is bonded so that the groove forming surface of the first substrate faces the second substrate. Such a microchip composed of two substrates includes a hollow portion formed by a groove provided on the surface of the first substrate and a surface of the second substrate facing the first substrate. A fluid circuit is provided.

  In another preferred embodiment, the microchip of the present invention is obtained by bonding a third substrate, a first substrate having grooves provided on both surfaces of the substrate, and a second substrate in this order. Become. The microchip including the three substrates includes a surface of the third substrate facing the first substrate and a groove provided on the surface of the first substrate facing the third substrate. A first fluid circuit, and a second substrate configured by a groove provided on a surface of the second substrate facing the first substrate and a surface of the first substrate facing the second substrate. And a two-layer fluid circuit. Here, “two layers” means that fluid circuits are provided at two different positions in the thickness direction of the microchip. The 1st fluid circuit and the 2nd fluid circuit may be connected by one or two or more penetration holes penetrated in the thickness direction formed in the 1st substrate.

  The method for bonding the substrates together is not particularly limited. For example, among the substrates to be bonded, at least one of the bonded surfaces of the substrates is melted and welded (welding method), and bonded using an adhesive. And the like. Examples of the welding method include a method in which the substrate is heated and welded; a method in which light is emitted from a laser or the like and the material is welded by heat generated during light absorption; and a method in which ultrasonic waves are used.

  The size of the microchip of the present invention is not particularly limited, and can be, for example, about several cm in length and width and about several mm to 1 cm in thickness.

  The material of each substrate constituting the microchip of the present invention is not particularly limited. For example, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polymethyl methacrylate (PMMA), polycarbonate (PC), polystyrene (PS) ), Polypropylene (PP), polyethylene (PE), polyethylene naphthalate (PEN), polyarylate resin (PAR), acrylonitrile-butadiene-styrene resin (ABS), vinyl chloride resin (PVC), polymethylpentene resin (PMP) Organic materials such as polybutadiene resin (PBD), biodegradable polymer (BP), cycloolefin polymer (COP), and polydimethylsiloxane (PDMS); inorganic materials such as silicon, glass, and quartz can be used.

  The first substrate, the second substrate, and the third substrate may be transparent substrates, and the substrate is made of a resin, and a colored substrate such as a black substrate is formed by adding carbon black or the like to the resin. However, in the case where the microchip is composed of two sheets of the first and second substrates, one substrate (for example, the first substrate which is a substrate having a groove forming a fluid circuit) is used as a transparent substrate. The other substrate (for example, the second substrate) is preferably a colored substrate such as a black substrate. When the substrate on the side where the grooves forming the fluid circuit are formed is a transparent substrate and the other substrate is a colored substrate, the substrates are bonded together by a welding method using light such as a laser. Since the bonding surface is mainly melted and bonded, deformation of the groove can be minimized. Further, when the microchip is composed of three substrates, ie, the first substrate, the second substrate, and the third substrate, the first substrate, which is the middle substrate, is a colored substrate such as a black substrate, and this is narrowed. It is preferable that the second and third substrates to be held are transparent substrates. As a result, even with a microchip consisting of three substrates, light is irradiated to a part (for example, a detection unit) containing a mixed liquid of a specimen and a liquid reagent to be examined and analyzed as described later. Optical measurement such as detecting the intensity (transmittance) of transmitted light can be performed.

  The method for forming grooves (pattern grooves) constituting the fluid circuit on the surface of the first substrate is not particularly limited, and examples thereof include an injection molding method using a mold having a transfer structure, an imprint method, and the like. it can. In the case of forming a substrate using an inorganic material, an etching method or the like can be used.

  In the microchip of the present invention, the fluid circuit (the first fluid circuit and the second fluid circuit in the case where two fluid circuits are provided) performs various processes appropriate for the liquid in the fluid circuit. In order to be able to do so, various parts arranged at appropriate positions in the fluid circuit are provided, and these parts are appropriately connected via fine flow paths.

  The microchip of the present invention is typically a liquid reagent built-in type microchip in which a liquid reagent is previously held in the chip, and the fluid circuit has a liquid reagent as one of the components constituting the liquid reagent. A liquid reagent holding unit for holding is provided. There may be only one liquid reagent holding part, or two or more liquid reagent holding parts. A “liquid reagent” is a substance (reagent) for mixing or reacting with a specimen to be examined / analyzed. Only one type of liquid reagent may be incorporated in one microchip, or two or more types of liquid reagents may be incorporated. Note that the “specimen” means a substance (for example, blood) to be examined / analyzed introduced into the fluid circuit, or a specific component (for example, a plasma component) in the substance.

  When the microchip of the present invention is a liquid reagent built-in type microchip having a liquid reagent holding part, a reagent injection port which is a through-hole penetrating to the internal liquid reagent holding part is provided on the surface of the substrate. Is normal. Such a microchip with a built-in liquid reagent is usually used after a liquid reagent is injected from the reagent inlet and then a label or seal for sealing the reagent inlet is attached to the surface of the microchip. Provided.

  In the present invention, the fluid circuit may include a part other than the liquid reagent holding part, such as a separation part for taking out a specific component from the specimen introduced into the fluid circuit; Sample measuring unit for measuring specific components. The same applies hereinafter.) Liquid reagent measuring unit for measuring liquid reagent; Mixing unit for mixing sample and liquid reagent; Examples include a detection unit for performing inspection / analysis (for example, detection or quantification of a specific component in a mixed solution). The microchip of the present invention may have all of these exemplified portions, or may not have any one or more. Moreover, you may have site | parts other than these illustrated site | parts. These portions are arranged at appropriate positions in the fluid circuit so as to perform a desired fluid treatment, and are connected through fine flow paths.

  The liquid mixture finally obtained by mixing the specimen and the liquid reagent is not particularly limited. For example, the liquid mixture that transmits the light by irradiating the portion (for example, the detection unit) containing the liquid mixture with light is transmitted. It is used for optical measurement such as a method for detecting intensity (transmittance), and inspection and analysis are performed.

  In a fluid circuit such as extraction of a specific component from a sample (separation of unnecessary components), measurement of a sample and / or a liquid reagent, mixing of a sample and a liquid reagent, introduction of the obtained mixture into a detection unit, etc. Various fluid treatments can be performed by sequentially applying a centrifugal force in an appropriate direction to the microchip. Application of centrifugal force to the microchip can be performed by placing the microchip on a device (centrifuge) that can apply centrifugal force. The centrifuge includes a rotor (rotor) and a rotatable stage installed on the rotor, and a centrifugal force is applied by placing a microchip on the stage and rotating the rotor. Can do. At this time, the direction of the centrifugal force applied to the microchip can be set to a desired direction by adjusting the angle of the microchip with respect to the rotor by rotating the stage.

  Here, the microchip of the present invention has fine irregularities formed on at least a part of its surface. When injecting a liquid reagent into the liquid reagent holding part, the injected liquid reagent flows backward through the reagent inlet and overflows on the surface of the microchip, or part of the liquid reagent scatters on the surface of the microchip. Liquid reagent droplets may adhere. By applying fine irregularities to the surface of the microchip, when liquid such as a liquid reagent adheres to the fine irregular surface, the surface area where the liquid has adhered does not cause irregular reflection of light. It looks darker than the area, and the presence or absence of liquid adhesion can be easily confirmed visually. On the other hand, the surface region to which no liquid is attached appears relatively bright due to irregular reflection due to fine irregularities. In this way, the presence or absence of liquid adhesion can be easily confirmed, thereby effectively preventing the outflow of defective products such as low adhesion of sealing labels or seals attached to the microchip surface. can do.

  The presence or absence of liquid adhesion can be sufficiently confirmed by visual observation, but may be performed using an image recognition device such as a CCD camera. When the image recognition apparatus is used, the brightness (brightness) of the surface is identified from the acquired image, and it is determined whether or not the liquid is attached.

  The height of the fine irregularities (distance from the bottom of the concave portion to the top of the convex portion) is not particularly limited, but is, for example, in the range of 0.1 to 10 μm, and preferably in the range of 1 to 5 μm. . If the height of the fine irregularities is less than 0.1 μm, it may be difficult to distinguish when the liquid is attached and when the liquid is not attached. On the other hand, if the height of the fine irregularities exceeds 10 μm, light reflection may occur despite the liquid adhering, and the liquid adhering surface may appear bright. The pitch of the fine unevenness, that is, the distance from the top of the projection to the next top is not particularly limited, but can be, for example, about 0.1 to 10 μm.

  As a method for forming fine unevenness on the substrate surface, a conventionally known method can be used. For example, when the substrate is produced by injection molding, blast treatment, discharge treatment or etching treatment is performed to form fine unevenness. And a method of forming fine irregularities by polishing the substrate surface using polishing paper or the like after forming the substrate or bonding the substrates together.

  FIG. 1 is a schematic perspective view showing an example of the microchip of the present invention, and FIG. 2 is a schematic cross-sectional view taken along the line II shown in FIG. A microchip 100 shown in FIGS. 1 and 2 includes a first substrate 101 that is a transparent substrate and a second substrate 102 that is a black substrate, each having a groove 103 that forms a fluid circuit on the surface. The substrate 101 is bonded so that the groove forming surface of the substrate 101 faces the second substrate 102. The upper surface of the microchip 100, that is, the surface opposite to the groove forming side (the second substrate 102 side) of the first substrate 101 is a surface region 105 having fine irregularities and a surface region not having fine irregularities. 106. In addition, the microchip 100 includes a reagent injection port 104 that is a through hole penetrating to a liquid reagent holding portion (not shown in FIG. 1) that is a part of the fluid circuit on the surface having the fine irregularities.

  The fine uneven surface of the microchip 100 will be described in more detail. First, the microchip 100 has a surface region 105 having fine irregularities around the two reagent injection ports 104 (see FIG. 1). When injecting a liquid reagent from the reagent injection port, the area where the liquid adheres due to overflowing on the microchip surface or part of the liquid reagent is often around the reagent injection port, As shown in FIG. 1, it is preferable to form a surface region having fine irregularities at least around the reagent inlet.

  In addition, in the case where the substrates are bonded to each other by a method in which the bonding surface of at least one substrate is melted and welded using light such as a laser, the fine irregularities on the microchip surface are grooves forming a fluid circuit. It is preferable to be formed in a part or all of the region where is formed. In the microchip 100, fine irregularities are formed only in the region A where the groove 103 is formed on the surface of the first substrate 101 opposite to the surface facing the second substrate 102, The surface region B (that is, the first substrate 101 in the first substrate 101) opposite to the surface region in contact with the second substrate 102 in the first substrate 101 (the bonded portion of the first substrate 101 to the second substrate 102). Of the surface opposite to the surface facing the second substrate 102, the surface region immediately above the bonded portion with the second substrate 102 does not have fine irregularities (see FIG. 2). By forming fine unevenness in the region where the groove is formed and not forming the fine unevenness in the surface region immediately above the bonded portion, light such as laser is irradiated from the surface side having the fine unevenness in the first substrate. Then, when melting and welding the bonded portion of one or both substrates, it is possible to avoid the problem that the irradiation light is scattered by fine unevenness and the transmittance of the irradiation light is reduced, and the substrate is efficiently Can be pasted together. In addition, the welding state of the bonded portion of one or both substrates can be confirmed using an image recognition device such as a CCD camera after the substrates are bonded, but fine irregularities are formed in the surface area immediately above the bonded portion. If so, the transparency of the first substrate 101, which is a transparent substrate, decreases, so that the confirmation may be difficult.

  In the case where the substrates are welded together using light such as a laser, when a transparent substrate and a colored substrate such as a black substrate are used like the microchip 100, the colored substrate has a higher light absorption rate. Primarily, the bonded portion of the colored substrate is melted and welded.

  FIG. 3 is a schematic cross-sectional view showing another example of the microchip of the present invention. A microchip 300 shown in FIG. 3 includes a second substrate 302 that is a transparent substrate, a first substrate 301 that is a black substrate, and has a groove 304 on one surface and a groove 305 on the other surface. The third substrate 303 which is a transparent substrate is bonded in this order. That is, the microchip 300 includes a fluid circuit (upper fluid circuit) formed by the groove 304 and the surface of the second substrate 302 on the first substrate 301 side, and the first of the groove 305 and the third substrate 303. 2 layers of fluid circuits (lower fluid circuit) formed by the substrate 301 side surface. Although not shown, the microchip 300 has a reagent inlet for injecting a liquid reagent onto the surface of the second substrate 302, and the reagent inlet is provided in the upper fluid circuit. It penetrates to the liquid reagent holding part. Then, fine irregularities are formed on a part of the upper surface of the microchip 300, that is, on the surface of the second substrate 302 opposite to the first substrate 301 side.

  In the microchip having such a configuration, the same can be said for the surface region where the fine unevenness is formed, as in the microchip including two substrates. That is, when the substrates are bonded together using light such as a laser, the fine irregularities on the surface of the microchip may be formed in a part or all of the region where the grooves constituting the fluid circuit are formed. preferable. In the microchip 300, fine irregularities are formed only in the region A ′ where the groove 304 is formed on the surface of the second substrate 302 opposite to the surface facing the first substrate 301. The surface region B ′ (that is, the second substrate 302) facing the surface region (the portion where the second substrate 302 is bonded to the first substrate 301) in contact with the first substrate 301 in the second substrate 302. In the surface on the opposite side of the surface facing the first substrate 301, the surface region immediately above the bonded portion with the first substrate 301 does not have fine irregularities (see FIG. 3).

  FIG. 4 is a schematic view showing still another example of the microchip of the present invention. FIG. 4 (a) is a schematic perspective view showing the periphery of the reagent inlet formed on the microchip surface, and FIG. 4 (b). FIG. 3 is a schematic cross-sectional view showing a peripheral portion of a reagent injection port. A microchip 400 shown in FIG. 4 includes a first substrate 401 having a groove that constitutes a fluid circuit, and a second substrate 402, and has a fluid circuit therein. A liquid reagent holding unit 403 is provided. A liquid reagent is held in the liquid reagent holding unit 403. A reagent injection port 405 for injecting a liquid reagent that penetrates to the liquid reagent holding unit 403 is formed in the first substrate 401. A recess 410 is provided on the surface of the first substrate 401 so as to surround the reagent injection port 405, and the microchip surface located between the recess 410 and the reagent injection port 405 has fine irregularities. A surface region 406 having fine irregularities is formed.

  As shown in FIG. 5A, when the sealing reagent 501 is pasted after the liquid reagent 502 is injected into the liquid reagent holding unit 403, the injected liquid reagent 502 is sealed by the surface tension. In some cases, the 501 and the surface of the first substrate 401 are distributed. In addition, as shown in FIG. 5B, when the liquid reagent 502 is injected, a part of the liquid reagent may scatter and the liquid reagent droplet 502 a may adhere to the surface of the first substrate 401.

  Even in such a case, by forming the recess so as to surround the reagent injection port, as shown in FIG. 6, the liquid reagent attached on the surface of the first substrate 401 is held in the recess 410, There is no oozing on the surface of the microchip outside the recess 410. Therefore, since the first substrate 401 and the sealing label 501 are bonded with good adhesion via the interfaces X and Y, the leakage of the liquid reagent after sealing is effectively avoided. be able to.

  Furthermore, if fine irregularities are formed on the microchip surface located between the reagent inlet 405 and the recess 410, the liquid reagent 502 is as shown in FIGS. 5 (a) and 5 (b). When it adheres to the surface of the microchip, it can be easily detected, so that the adhesion at the interface Z shown in FIG. 6 can be secured, and the reliability of the manufactured microchip is further increased. Can be improved.

  In addition, the shape of the recessed part 410 is not limited to circular shape, For example, it can be set as appropriate shapes, such as elliptical shape, rectangular shape, square shape, triangular shape. The width and depth of the groove are not particularly limited, and the amount of liquid reagent that can adhere to the microchip surface is normally considered to be about 0.1 to 5 μl. More specifically, although not particularly limited, the width and depth of the recess can be about 1 mm.

  When the microchip holds a plurality of liquid reagents, the microchip has a plurality of reagent inlets. In this case, it is preferable to provide a recess around each reagent inlet. The shapes of the plurality of recesses may be the same or different.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these.

<Example 1>
FIG. 7 is a CCD image showing the top surface of the microchip of this example. The microchip of this example includes a first substrate that is a transparent substrate and a second substrate that is a black substrate, each having a groove that forms a fluid circuit on one surface, and a groove forming side of the first substrate. The surface is bonded so as to face the second substrate, and the first substrate has fine irregularities on the surface opposite to the groove forming surface. FIG. 7 is a CCD image showing the surface on which the fine irregularities are formed. In the microchip of this example, the fine irregularities are formed on almost the entire surface of the first substrate.

  The microchip of this example was manufactured as follows. First, using a resin such as PET, a first substrate having a groove constituting a fluid circuit is produced by injection molding, and then this is formed into a flat plate-like second substrate having substantially the same outer shape (resin such as PET). The substrate to which carbon black was added was bonded by laser welding. In laser welding, after laminating the first substrate on the second substrate, laser irradiation is performed from the first substrate side, which is a transparent substrate, to mainly melt the bonding surface of the second substrate. The substrates were bonded by pressure-bonding both substrates. Next, a polishing process was performed on the surface of the first substrate of the obtained microchip to form fine irregularities in a region as shown in FIG. 7 to obtain a microchip having fine irregularities.

  FIG. 8 is a CCD image when a liquid reagent (test reagent aqueous solution) is attached to a part of the fine uneven surface of the microchip of the present embodiment shown in FIG. As is clear from FIG. 8, when the liquid adheres to the surface of the fine irregularities, the portion looks darker than the portion where the liquid does not adhere (round portion at the upper left of the microchip center). It turns out that it can confirm easily.

  FIG. 9 is a top view showing the fluid circuit structure of the microchip of this example. Actually, the grooves constituting the fluid circuit are formed on the surface of the first substrate opposite to the surface shown in FIG. 9, but in order to clearly show the fluid circuit structure, in FIG. The fluid circuit is shown by a solid line. The microchip of this example includes a sample tube mounting unit 901 for incorporating a sample tube such as a capillary containing whole blood collected from a subject, blood cells from the whole blood derived from the sample tube, and plasma components A plasma separating unit 902 for obtaining a sample, a sample measuring unit 903 for measuring a separated plasma component, two liquid reagent holding units 904a and 904b for holding a liquid reagent, and two liquid reagent measuring units 905a for measuring a liquid reagent, 905b, mainly composed of mixing units 906a to 906d for mixing the plasma component and the liquid reagent, and a detection unit 907 for performing inspection / analysis on the obtained mixed solution. The two liquid reagent holding units 904a and 904b have reagent injection ports 910a and 910b for injecting liquid reagents, respectively.

  The operation method of the microchip of the present embodiment is roughly as follows. The operation method described below is an example, and the present invention is not limited to this method. First, a sample tube from which a whole blood sample is collected is inserted into the sample tube mounting portion 901. Next, a centrifugal force is applied to the microchip in the right direction in FIG. 9 (hereinafter simply referred to as right direction; the same applies to the other directions below), and the whole blood sample in the sample tube is taken out, and then the downward direction is applied. The whole blood sample is introduced into the plasma separation unit 902 by centrifugal force and centrifuged to separate the plasma component and the blood cell component. When the whole blood sample is introduced into the plasma separation unit 902, the whole blood sample overflowing from the plasma separation unit 902 is accommodated in the waste liquid storage unit 908. By this downward centrifugal force, the liquid reagent M in the liquid reagent holding unit 904a is measured by the liquid reagent measuring unit 905a.

  Next, the separated plasma component is introduced into the sample measuring unit 903 by leftward centrifugal force. At this time, the measured liquid reagent M moves to the mixing unit 906b, and the liquid reagent N in the liquid reagent holding unit 904b is discharged from the liquid reagent holding unit 904b.

  Next, the measured plasma component and the liquid reagent M are mixed by the mixing unit 906a by the downward centrifugal force, and the liquid reagent N is measured by the liquid reagent measuring unit 905b. Next, leftward, downward, and leftward centrifugal forces are sequentially applied to move the mixed solution back and forth between the mixing units 906a and 906b, thereby sufficiently mixing the mixed solution. Next, the mixed liquid composed of the liquid reagent M and the plasma component and the measured liquid reagent N are mixed in the mixing unit 906c by upward centrifugal force. Next, rightward, upward, rightward, and upward centrifugal forces are sequentially applied to move the mixed solution back and forth between the mixing units 906c and 906d, thereby sufficiently mixing the mixed solution. Finally, the mixed liquid in the mixing unit 906c is introduced into the detection unit 907 by leftward centrifugal force. The liquid mixture in the detection unit 907 is subjected to optical measurement such as, for example, irradiating the detection unit 907 with light and measuring the intensity of the transmitted light.

<Comparative Example 1>
FIG. 10 is a CCD image showing the upper surface of the microchip of this comparative example. The microchip shown in FIG. 10 is the same as the microchip of Example 1 except that fine irregularities are not formed on the surface. FIG. 11 is a CCD image when a liquid reagent (test reagent aqueous solution) is attached to a part (the same position as FIG. 8) on the surface of the microchip of this comparative example shown in FIG. . As can be seen from FIGS. 10 and 11, when the fine unevenness is not formed, there is almost no difference in the surface brightness between the area where the liquid is attached and the area where the liquid is not attached. It turns out that it is very difficult to confirm whether it has adhered.

<Example 2>
FIG. 12 is a CCD image showing a partially enlarged top surface of the microchip of this example. The microchip shown in FIG. 12 is the same as that of Example 1 except that fine irregularities are formed only on the surface area where the liquid reagent holding portion 904a (see FIG. 9) is located on the microchip surface. In FIG. 12, a black line is a fluid circuit wall formed on the back side, that is, a region where a groove constituting the fluid circuit is not formed. Therefore, in the microchip of the present embodiment, the fine irregularities are formed only in the area around the reagent injection port and in which the groove constituting the fluid circuit is formed.

  FIG. 13 is a CCD image when a liquid reagent (test reagent aqueous solution) is attached to a part (right side of the reagent injection port) on the fine uneven surface of the microchip shown in FIG. As can be seen from FIG. 13, when the liquid adheres on the surface of the fine irregularities, the portion looks darker than the portion where the liquid does not adhere, and the presence or absence of the liquid can be easily confirmed.

<Example 3>
FIG. 14 is a CCD image showing a partially enlarged top surface of the microchip of this example. The microchip shown in FIG. 14 is the same as that of Example 1 except that the microchip surface is formed with fine irregularities only around the reagent inlet 910b of the liquid reagent holding unit 905a (see FIG. 9). .

  FIG. 15 is a CCD image when a liquid reagent (test reagent aqueous solution) is attached to a part (upper left of the reagent injection port) on the fine uneven surface of the microchip shown in FIG. As can be seen from FIG. 15, when the liquid adheres to the surface of the fine irregularities, the portion looks darker than the portion where the liquid does not adhere, and the presence or absence of the liquid can be easily confirmed.

  It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a schematic perspective view which shows an example of the microchip of this invention. It is a schematic sectional drawing in the II line | wire of FIG. It is a schematic sectional drawing which shows another example of the microchip of this invention. It is a schematic sectional drawing which shows another example of the microchip of this invention. It is a schematic sectional drawing explaining the state at the time of sticking the sealing label on the microchip shown by FIG. 4 with which the liquid reagent adhered to the surface. It is a schematic sectional drawing explaining a state when the label for sealing is affixed on the microchip shown by FIG. 4 with which the liquid reagent adhered to the surface. 2 is a CCD image showing the upper surface of the microchip of Example 1. FIG. FIG. 3 is a CCD image when a liquid reagent is attached to a part of the fine uneven surface of the microchip of Example 1. FIG. 1 is a top view showing a fluid circuit structure of a microchip of Example 1. FIG. 6 is a CCD image showing the upper surface of the microchip of Comparative Example 1. 6 is a CCD image when a liquid reagent is attached to a part of the surface of the microchip of Comparative Example 1. FIG. 4 is a CCD image showing a partially enlarged upper surface of the microchip of Example 2. It is a CCD image when a liquid reagent is made to adhere to a part on the fine uneven surface of the microchip of Example 2. 6 is a CCD image showing a partially enlarged upper surface of the microchip of Example 3. FIG. 5 is a CCD image when a liquid reagent is attached to a part of the fine uneven surface of the microchip of Example 3. FIG.

Explanation of symbols

  100, 300, 400 microchip, 101, 301, 401 first substrate, 102, 302, 402 second substrate, 103, 304, 305 groove, 104 reagent injection port, 105, 406 surface region having fine irregularities, 106 surface area without fine irregularities, 303 third substrate, 403 liquid reagent holding part, 405, 910a, 910b reagent inlet, 410 recess, 501 sealing label, 502 liquid reagent, 502a liquid reagent droplet, 901 Sample tube placement unit, 902 Plasma separation unit, 903 Sample measurement unit, 904a, 904b Liquid reagent holding unit, 905a, 905b Liquid reagent measurement unit, 906a, 906b, 906c, 906d Mixing unit, 907 detection unit, 908 Waste liquid reservoir Department.

Claims (4)

At least a first substrate having a groove on the surface and a second substrate are bonded together so that a groove forming side surface of the first substrate faces the second substrate. A microchip having
A liquid reagent holding unit for holding a liquid reagent constituting a part of the fluid circuit;
Reagent injection for injecting the liquid reagent into the liquid reagent holding portion formed on the second surface of the first substrate opposite to the first surface facing the second substrate. The entrance,
A recess formed on the second surface so as to surround the reagent inlet;
With
A microchip in which fine irregularities are formed on the second surface located between the reagent inlet and the recess. A microchip having a fluid circuit inside, wherein the second substrate, the first substrate having grooves on both surfaces, and the third substrate are bonded together in this order,
A liquid reagent holding unit for holding a liquid reagent constituting a part of the fluid circuit;
Reagent injection for injecting the liquid reagent into the liquid reagent holding portion formed on the second surface of the second substrate opposite to the first surface facing the first substrate. The entrance,
A recess formed on the second surface so as to surround the reagent inlet;
With
A microchip in which fine irregularities are formed on the second surface located between the reagent inlet and the recess. The second a surface, the microchip according to claim 1 or 2, further the fine irregularities on part or all of a region where the groove is formed is formed. The microchip according to any one of claims 1 to 3 , wherein a height of the fine unevenness is in a range of 0.1 to 10 µm.