Reagent-carrying substrate, reagent-containing microchannel structure, and reagent-containing microchannel device

Abstract

To provide a reagent-carrying base material capable of immobilizing a freeze-dried formulation even in a small container (e.g., a microchannel structure) smaller than the size of a syringe, and a microchannel structure containing a reagent having a microchannel in which a freeze-dried formulation is immobilized.SOLUTION: The present disclosure is related to a microchannel structure containing a reagent, which includes: a base material; a cover material arranged on one side of the base material; a spacer arranged between the base material and the cover material; and a microchannel that is partitioned by the base material, the cover material, and the spacer and extends in a direction perpendicular to the thickness direction of the base material. At least one of the base material and the cover material is a porous material having a pore size of 2.0 μm or less, and a freeze-dried formulation is immobilized in the microchannel.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present disclosure relates to a reagent-carrying substrate, a reagent-containing microchannel structure, and a reagent-containing microchannel device. [Background technology]

[0002] Freeze-drying has traditionally been used as a method for stably preserving pharmaceuticals. Drugs obtained by freeze-drying (hereinafter sometimes referred to as freeze-dried preparations) have the advantages of minimal changes in the substance's structure, maintaining their original shape, and good reconstitution. Furthermore, freeze-dried preparations can be stored for longer periods than liquid preparations, and can also be stored at room temperature.

[0003] The general method of freeze-drying involves first filling a dissolved drug into a vial or similar, partially sealing it with a rubber stopper, and freezing it at a low temperature (pre-freezing). Next, free water is sublimated and removed from the pre-frozen product under reduced pressure (primary drying). Next, the bound water remaining after the primary drying is sublimated and removed from the pre-frozen product (secondary drying). This results in a cotton candy- or spider web-like solid called a cake, which has a high porosity and has no moisture left from the frozen product, and is then stoppered under negative pressure and stored.

[0004] In recent years, reagent syringes (pre-filled syringes) filled with reagents such as freeze-dried preparations and powders have become available, but in order to reduce the amount of medicine and sample used, there is a demand for further miniaturization of reagent containers, and there is a demand for reagent containers smaller than the size of syringes.

[0005] In response to the demand for miniaturization of such reagent-containing containers, for example, Patent Document 1 discloses immobilizing a reagent on a microchannel device. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Special Publication No. 2007-501020 Summary of the Invention [Problem to be solved by the invention]

[0007] However, when a reagent solution is introduced into a microchannel, frozen, and then dried under high vacuum, it becomes difficult to control the temperature during freezing within the microchannel and the amount of ice sublimation during drying, which can cause the reagent to spray out from the opening of the microchannel structure during drying. Another possible method is to fill a small container with cake powder prepared in a vial, but this method has many issues and is not widely used. Therefore, drying the reagent solution at room temperature under low vacuum has been considered, but the resulting protein coating is not very bulky and has a small surface area, making it time-consuming to redissolve.

[0008] Therefore, there has been a demand for a method that allows freeze-dried reagents to be fixed in small containers. The present disclosure has been made in consideration of the above-mentioned problems, and has as its main object to provide a reagent-supporting substrate capable of immobilizing a freeze-dried formulation even in a small container (e.g., a microchannel structure) smaller than the size of a syringe, and a reagent-filled microchannel structure having a microchannel in which a freeze-dried formulation is immobilized. [Means for solving the problem]

[0009] The present disclosure provides a reagent-supported substrate having a porous substrate containing an inorganic material and a freeze-dried formulation supported in the pores of the porous substrate. In addition, in this disclosure, the thermal conductivity is 0.5 W m -1 ·K -1 The present invention provides a reagent-supporting substrate comprising a porous substrate having the above-mentioned material and a freeze-dried preparation supported in the pores of the porous substrate.

[0010] The present disclosure further provides a reagent-containing microchannel structure having a substrate, a cover material arranged on one surface of the substrate, a spacer arranged between the substrate and the cover material, and a microchannel partitioned by the substrate, the cover material, and the spacer and extending in a direction perpendicular to the thickness direction of the substrate, wherein the above-mentioned reagent-carrying substrate is arranged in the microchannel.

[0011] The present disclosure provides a reagent-filled microchannel structure comprising: a substrate; a cover material disposed on one surface of the substrate; a spacer disposed between the substrate and the cover material; and a microchannel partitioned by the substrate, the cover material, and the spacer and extending in a direction perpendicular to the thickness direction of the substrate, wherein at least one of the substrate and the cover material is a porous material having a pore size of 2.0 μm or less; and a freeze-dried preparation is immobilized in the microchannel.

[0012] The present disclosure further provides a reagent-containing microchannel device comprising: a substrate; a cover material arranged on one surface of the substrate; a spacer arranged between the substrate and the cover material; a microchannel partitioned by the substrate, the cover material, and the spacer and extending in a direction perpendicular to the thickness direction of the substrate; and a conductor layer arranged on the substrate in a region where the microchannel is formed, wherein the above-mentioned reagent-carrying substrate is arranged in the microchannel.

[0013] The present disclosure also provides a reagent-filled microchannel device comprising: a substrate; a cover material disposed on one surface of the substrate; a spacer disposed between the substrate and the cover material; a microchannel partitioned by the substrate, the cover material, and the spacer and extending in a direction perpendicular to the thickness direction of the substrate; and a conductor layer disposed on the substrate in a region where the microchannel is formed, wherein at least one of the substrate and the cover material is a porous material having a pore size of 2.0 μm or less, and a freeze-dried preparation is immobilized in the microchannel. [Effects of the Invention]

[0014] According to the reagent-carrying substrate of the present disclosure, it is possible to immobilize a freeze-dried reagent even in a small container (for example, a microchannel structure) smaller than the size of a syringe. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a schematic cross-sectional view illustrating a reagent-carrying substrate according to the present disclosure. [Figure 2] 1A and 1B are a schematic plan view and a cross-sectional view illustrating a reagent-containing microchannel structure according to a first embodiment of the present disclosure. [Figure 3] FIG. 1 is a schematic plan view illustrating a microchannel according to the present disclosure. [Figure 4] FIG. 1 is a schematic plan view illustrating a microchannel according to the present disclosure. [Figure 5] 1 is a schematic cross-sectional view illustrating a reagent-containing microchannel structure (first embodiment) according to the present disclosure. [Figure 6] 1A to 1C are schematic process diagrams illustrating a method for manufacturing a microchannel structure (first embodiment) according to the present disclosure. [Figure 7] 5A to 5C are schematic process diagrams illustrating another method for manufacturing the microchannel structure (first embodiment) of the present disclosure. [Figure 8] 10A and 10B are a schematic plan view and a cross-sectional view illustrating a reagent-containing microchannel structure according to a second embodiment of the present disclosure. [Figure 9] 1 is a schematic cross-sectional view illustrating a reagent-containing microfluidic device (first embodiment) according to the present disclosure. [Figure 10] FIG. 1 is a schematic cross-sectional view illustrating a reagent-containing microfluidic device (second embodiment) according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0016] Embodiments of the present disclosure will be described below with reference to the drawings and the like. However, the present disclosure can be implemented in many different forms, and should not be construed as being limited to the description of the embodiments exemplified below. Furthermore, to clarify the explanation, the drawings may schematically depict the width, thickness, shape, etc. of each part compared to the actual form, but these are merely examples and are not intended to limit the interpretation of the present disclosure. Furthermore, in this specification and each drawing, elements similar to those previously described with reference to the preceding drawings will be designated by the same reference numerals, and detailed descriptions may be omitted as appropriate.

[0017] In this specification, when describing a mode in which another component is placed on a certain component, the terms "above" or "below" are used, unless otherwise specified, to include both a case in which another component is placed directly above or below a certain component so as to be in contact with the component, and a case in which another component is placed above or below a certain component with another component interposed therebetween. Also, in this specification, when describing a mode in which another component is placed on the surface of a certain component, the terms "on the surface side" or "on the surface" are used, unless otherwise specified, to include both a case in which another component is placed directly above or below a certain component so as to be in contact with the component, and a case in which another component is placed above or below a certain component with another component interposed therebetween.

[0018] The reagent-carrying substrate, the reagent-containing microchannel structure, and the reagent-containing microchannel device of the present disclosure will be described in detail below.

[0019] A. Reagent-carrying substrate A-1. First aspect The reagent-supporting substrate in this embodiment is characterized by having a porous substrate containing an inorganic material and a freeze-dried preparation supported in the pores of the porous substrate. The reagent-carrying substrate in this embodiment will be described with reference to the drawings. Fig. 1 is a schematic cross-sectional view showing an example of a reagent-carrying substrate in the present disclosure. The reagent-carrying substrate 10 in the present disclosure has a porous substrate 1 containing an inorganic material and a freeze-dried preparation R carried in the pores of the porous substrate 1.

[0020] The porous substrate in the reagent-carrying substrate of this embodiment has good thermal conductivity due to the inorganic material contained in the porous substrate, making it easy to control the temperature during freeze-drying of the reagent solution. Furthermore, the freeze-dried formulation is captured and supported in the voids of the inorganic material, thereby ensuring its immobilization. Furthermore, the reagent-carrying substrate of the present disclosure can be easily adjusted in size by cutting. For example, the substrate can be cut to a size that can be placed in the microchannel of a microchannel structure, and then inserted and placed in the microchannel, thereby immobilizing the freeze-dried formulation in the microchannel.

[0021] 1. Porous base material The porous substrate in this embodiment contains a plurality of voids therein, and these voids usually preferably communicate with each other in the liquid-transfer direction of the microchannel, because this allows for efficient liquid transfer of reagent solutions and other liquids. The porosity of the porous substrate is not particularly limited, but is preferably 50% or more, and particularly preferably 75% or more. If it is above this value, a sufficient amount of the freeze-dried preparation can be supported. On the other hand, it is preferably 99% or less, and particularly preferably 97% or less. If it is below this value, the content of the inorganic material is sufficient, and excellent thermal conductivity due to the inorganic material can be ensured.

[0022] In this embodiment, the porosity refers to the proportion of voids in the porous substrate, It can be calculated as follows: Pv(%) = {(Va-Vt) / Va} × 100 (1) Pv (%): Porosity of porous substrate (volume %) Va: Apparent volume of porous substrate Vt: Theoretical volume of porous substrate Here, Va can be calculated from the length, width, and thickness values ​​of the inorganic porous substrate, and Vt can be calculated from the weight of the porous substrate, the weight ratio of the constituent materials, and the true specific gravity value of each of the constituent materials.

[0023] The thermal conductivity of the porous substrate is, for example, 0.5 W m -1 ·K-1 More than 0.7 W m is preferable, and 0.7 W m is particularly preferable. -1 ·K -1 If the value is equal to or greater than the above, the thermal conductivity of the porous substrate is sufficiently high, making it easy to control the temperature during freeze-drying. On the other hand, there is no particular upper limit to the thermal conductivity, but for example, it is 500 W m -1 ·K -1 Below 250 W·m -1 ·K -1 The following is the result.

[0024] Examples of inorganic materials include general inorganic materials, particularly ceramics made of metal oxides, as well as metals and carbon materials. The inorganic material is preferably fibrous or needle-like in shape, as this provides high strength and makes it easy to form a porous substrate.

[0025] Furthermore, the porous substrate is preferably an inorganic fiber molded body made by papermaking inorganic fibers or an inorganic fiber molded body formed into a net shape. Examples of inorganic fibers include glass fibers, alumina fibers, carbon fibers, and ceramic fibers.

[0026] Specific examples of inorganic fiber molded articles include glass paper, alumina fiber paper, carbon fiber paper, ceramic fiber paper, and films and sheets formed from the above inorganic fibers in a net shape, with glass paper being preferred among them.

[0027] The size of the inorganic fibers constituting the porous substrate is not particularly limited, and for example, the fiber diameter is preferably 0.1 μm or more, more preferably 1.0 μm or more. The fiber diameter is preferably 50 μm or less, more preferably 20 μm or less. The fiber diameter is the maximum diameter in a cross section perpendicular to the longitudinal direction of the inorganic fiber. Furthermore, the length of the inorganic fibers in the longitudinal direction (inorganic fiber length) is preferably 0.1 mm or more, more preferably 0.5 mm or more, and is preferably 50 mm or less, more preferably 20 mm or less.

[0028] The inorganic fibers constituting the inorganic fiber molded body are in contact with each other at their intersections, and these intersections may be bonded by a binder, or the fibers themselves may be entangled without a binder. The binder preferably contains a water-soluble resin. Specific examples of water-soluble resins that can be used include polyvinyl alcohol resins, (meth)acrylic resins, and epoxy resins. In this specification, "(meth)acrylic" means "acrylic" or the corresponding "methacrylic."

[0029] As described above, glass paper is particularly preferable as the porous substrate. The glass paper has a structure in which glass fibers are bound by a binder (a water-soluble resin). The glass paper preferably has a basis weight of 8 g / m 2 More preferably, 15 g / m 2 If the thickness is equal to or greater than the above value, the amount of glass fiber is sufficient and excellent thermal conductivity can be ensured. Preferably, it is 700 g / m 2 or less, more preferably 400 g / m 2 If the thickness is equal to or less than the above value, there is no risk of physically impeding the flow of the liquid, and there is no risk of impeding weight reduction.

[0030] Porous substrates containing inorganic materials, such as glass paper, have higher heat resistance and are resistant to dry heat sterilization treatments than resins and the like. Therefore, the porous substrate can be sterilized by dry heat sterilization before loading a lyophilized formulation. Such sterilized porous substrates, when used in the manufacture of microchannel devices used in detection tests for microbial contaminants such as endotoxins, can improve the accuracy of the detection test. Furthermore, unintended adverse effects of endotoxins on reactions occurring within the microchannels can be suppressed.

[0031] 2. Lyophilized formulation The reagent-carrying substrate in this embodiment has a lyophilized preparation carried in the pores of a porous substrate. Lyophilized preparations usually have a porous structure. A porous structure has a larger surface area than a non-porous structure, allowing for rapid mixing of the reagent and the sample, and also has advantages such as good reconstitution (resolubility). Here, the freeze-dried preparation in this embodiment may be any preparation having a moisture content and shape specific to freeze-dried preparations, but in particular, a freeze-dried preparation in this embodiment may be any preparation having a moisture content of 3.0% by mass or less, preferably 1.0% by mass or less, a foam cake structure with a wall thickness in the range of 0.1 μm to 10 μm, and a void diameter in the range of 10 μm to 500 μm, in which a wall structure (honeycomb-like or truss-like) can be observed under a microscope. In general, since the water in a drug product obtained by air drying is evaporated from the beginning, the water content of the drug product layer of several tens of microns or more is high, and the drug product is in a starch syrup state, and the wall structure described above is not observed.

[0032] The reagent used in the present disclosure is selected appropriately depending on the application of the reagent-carrying substrate and is not particularly limited. In the present disclosure, from the viewpoint of freeze-drying, proteins and chemical substances with unstable higher-order structures as liquids are preferable. Examples of the proteins include enzymes, antibodies, protein preparations that are cells or parts thereof, vaccines, etc., and examples of the chemical substances with higher-order structures include antibiotics, microRNA, aptamers, etc. The reagent may be used alone or in combination of two or more types.

[0033] For example, in recent years, when metastatic cancer is a concern, there has been a demand for microchannels that store, as a support with a wide adsorption area, antibodies or the like that recognize and adsorb cancer-specific cell surface antigens in the microchannel chamber to treat cancer cells that have dispersed from organs into the blood. The microchannel structure of the present disclosure can support such antibodies on a porous substrate within the channel, making it suitable for use as a cancer cell testing sensor.

[0034] The reagent-carrying substrate of the present disclosure can be obtained by impregnating the porous substrate with a reagent solution and freeze-drying it using a conventional method. Impregnation of the porous substrate with the reagent solution can be achieved by applying the reagent solution to the porous substrate or by immersing the porous substrate in the reagent solution. The application may be performed over the entire main surface of the porous substrate, or may be performed over a portion of the main surface (e.g., in a pattern). The reagent solution contains at least a reagent and a solvent that dissolves or disperses the reagent.

[0035] Freeze-drying is usually carried out by pre-freezing the reagent solution, followed by primary drying, in which free water is removed from the pre-frozen product by sublimation under reduced pressure, and secondary drying, in which bound water remaining after primary drying is removed from the freeze-dried cake by sublimation. These conditions are set appropriately depending on the type of reagent. For example, a freeze-dried product can be obtained by pre-freezing at −210 to −25°C for 10 minutes to 2 hours, drying at −50 to −10°C for 4 to 24 hours under reduced pressure of 5 Pa to 20 Pa (primary drying), and further drying at −20 to 55°C for 1 to 36 hours (secondary drying).

[0036] 3.Applications The reagent-carrying substrate according to the present disclosure can be cut to an appropriate size to be inserted into a small container smaller than the size of a syringe, and the freeze-dried reagent liquid can be immobilized in the small container. Specifically, by inserting and arranging the reagent-carrying substrate cut to an appropriate size into a microchannel of a microchannel structure, the freeze-dried reagent can be immobilized in the microchannel. Another application is a reagent-carrying substrate for subcutaneous implants. In this case, a biopharmaceutical or hormone can be freeze-dried and immobilized on the substrate for the purpose of treatment or temporary health management. Such a reagent-carrying substrate is sized to fit into an applicator and is placed subcutaneously through the applicator. The reagent is slowly released subcutaneously and absorbed intravenously.

[0037] A-2. Second mode The reagent-carrying substrate of this embodiment has a thermal conductivity of 0.5 W m -1 ·K-1 The present invention is characterized by comprising a porous substrate having the above-mentioned material and a freeze-dried preparation supported in the pores of the porous substrate.

[0038] The difference between the reagent-carrying substrate of this embodiment and the reagent-carrying substrate of the first embodiment is that the porous substrate of the first embodiment must contain an inorganic material, whereas the reagent-carrying substrate of this embodiment must contain an inorganic material with a thermal conductivity of 0.5 W m -1 ·K -1 The point is that the material has the above properties.

[0039] Such a material is not particularly limited, and may be either an organic material or an inorganic material. As the inorganic material, those described in the first embodiment above can be used. On the other hand, as an organic material, for example, when carbon graphite is contained in a thermoplastic resin, the apparent thermal conductivity increases, and this may be used as a fiber such as a spunbond. Other aspects of the reagent-carrying substrate of this embodiment are the same as those of the first embodiment, and therefore will not be described here.

[0040] B. Microchannel structure containing reagent (first embodiment) The present disclosure provides a reagent-containing microchannel structure comprising: a substrate; a cover material disposed on one side of the substrate; a spacer disposed between the substrate and the cover material; and a microchannel partitioned by the substrate, the cover material, and the spacer and extending in a direction perpendicular to the thickness direction of the substrate, wherein the reagent-carrying substrate shown in "A. Reagent-carrying substrate" above is disposed in the microchannel.

[0041] Fig. 2(a) is a schematic plan view showing an example of a reagent-containing microchannel structure according to the present disclosure, Fig. 2(b) is a cross-sectional view taken along line AA of Fig. 2(a), and Figs. 2(c) and 2(d) are cross-sectional views taken along line BB of Fig. 2(a). The freeze-dried formulation is omitted from Figs. 2(a) to 2(c), while the freeze-dried formulation R is fully illustrated in Fig. 2(d). The reagent-containing microchannel structure 100 shown in Fig. 2 includes a substrate 11, a cover material 12 disposed on one side of the substrate 11, a spacer 13 disposed between the substrate 11 and the cover material 12, and a microchannel 14. The microchannel structure has the above-described porous substrate 15 carrying the freeze-dried formulation R disposed in the microchannel 14.

[0042] 2, porous substrate 15 is disposed over the entire microchannel 14 in a plan view. In addition, porous substrate 15 is disposed over the entire microchannel 14 in the thickness direction of substrate 11. Each member will be described in detail below.

[0043] The reagent-containing microchannel structure of the present disclosure has the above-mentioned reagent-carrying substrate disposed in the microchannel. The porous substrate in the reagent-carrying substrate has good thermal conductivity, which facilitates temperature control during freeze-drying of the reagent introduced into the pores of the porous substrate, making freeze-drying within the microchannel easy. Furthermore, the freeze-dried preparation is captured and supported in the pores of the porous substrate, ensuring reliable immobilization. Therefore, the reagent-containing microchannel structure of the present disclosure is prevented from spraying out of the reagent from the opening.

[0044] 1. Microfluidic Channel The microchannel is defined by a substrate, a cover material, and a spacer, extends in a direction perpendicular to the thickness direction of the substrate, and functions to transport a liquid in the extension direction. The microchannel in the present disclosure is provided with a porous substrate having good thermal conductivity. Therefore, for the reasons described above, the reagent-containing microchannel structure in the present disclosure is prevented from causing the reagent to spurt out of the opening.

[0045] (1) Porous base material The porous substrate has multiple voids inside, contains inorganic material, or has a thermal conductivity of 0.5 W m -1 ·K -1 The porous substrate is a layer made of the above-mentioned material and disposed in the microchannel. Examples of the porous substrate include those similar to those described in "A. Reagent-carrying substrate" above.

[0046] Furthermore, when the porous substrate of the present disclosure is made of an inorganic material, it has better wettability to liquids than, for example, resin materials such as PET. Therefore, liquids passing through the pores of such porous substrates tend to spread and are easily drawn into the flow channel by capillary action, and the liquid flows more easily through the microchannel. Furthermore, by disposing a porous substrate containing an inorganic material in the microchannel, the amounts of various specimens and reagents used can be reduced compared to conventional microchannels.

[0047] The porous substrate may be disposed over a part or the entire microchannel in a plan view, but in normal applications, it is preferable that the porous substrate be disposed over the entire microchannel. In the present disclosure, the plan view means a view from the thickness direction of the substrate.

[0048] The term "arranged in a part of the microchannel" may mean that the microchannel is arranged in a part of a cross section perpendicular to the liquid-flow direction, or that the microchannel is arranged in a part of a cross section parallel to the liquid-flow direction.

[0049] In addition, in the thickness direction of the substrate, the electrodes may be disposed in a part of the microchannel or in the entirety thereof, but it is usually preferable that the electrodes be disposed in the entirety thereof.

[0050] (2) Lyophilized preparation The reagent-carrying substrate carries a freeze-dried preparation. Examples of freeze-dried preparations include those described in detail in "A. Reagent-carrying substrate 2. Freeze-dried preparation" above, and therefore further description will be omitted here. In the present disclosure, the region in which the freeze-dried preparation is supported on the porous substrate may be the entire porous substrate or a part of the porous substrate.

[0051] (3) Microchannel A microchannel is a tiny channel that generates micro effects when transporting liquid. In such a microchannel, the liquid is strongly affected by surface tension and behaves differently from liquid flowing through a normal large channel.

[0052] The channel width (W in FIG. 2(b)) of the microchannel in the present disclosure is preferably 50 mm or less, and particularly preferably 20 mm or less. On the other hand, it is preferably 20 μm or more, and particularly preferably 50 μm or more. Within the above range, the arrangement of the porous substrate becomes easy and capillary action can be generated. The channel width is the width of the microchannel in the channel cross section cut perpendicular to the extension direction of the microchannel.

[0053] The height of the microchannel (H in FIG. 2(b)) is preferably 10 mm or less, and particularly preferably 5 mm or less. On the other hand, it is preferably 50 μm or more, and particularly preferably 100 μm or more. Within the above range, the arrangement of the porous substrate becomes easy and capillary action can be generated.

[0054] The width of the microchannel may be constant or variable. For example, when the microchannel has a placement section (described later), the placement section may be wide, and the area other than the placement section may be narrow. Specifically, the width of the area other than the placement section in the microchannel is the width of the microchannel described above, and the width of the placement section in the microchannel may be 20 μm or more and 50 mm or less. If the width of the placement section in the microchannel is within the above range, the liquid can flow stably through the microchannel due to capillary action, and testing can be performed with high sensitivity.

[0055] The length of the microchannel is set appropriately depending on the type of reagent to be immobilized, the type of liquid to be delivered, the application of the microchannel structure, etc., and can be, for example, 5 mm or more, preferably 25 mm or more. The length can be 1000 mm or less, preferably 500 mm or less. The shape of the cross section of the microchannel cut perpendicular to the liquid delivery direction is usually rectangular, but may also be, for example, arched, trapezoidal, triangular, etc.

[0056] The shape of the microchannel in plan view is not particularly limited and may be linear, curved, branched, or a combination of these. One microchannel structure may contain one or more microchannels, or two or more microchannels. Specific embodiments of microchannels contained in the microchannel structure are shown in Figures 3 and 4. Figures 3(a) to (c) and Figures 4(a) to (c) are schematic plan views in which the cover material, the porous substrate in the microchannel, and the lyophilized preparation are omitted.

[0057] Figure 3(a) shows an embodiment in which multiple linear microchannels are arranged in parallel. In this case, the number of channels (N) can be increased, improving testing accuracy. Figures 3(b) and 3(c) show an embodiment in which two or three microchannels merge into one microchannel. In this case, it is possible to mix or react two or more liquids. Figure 4(a) shows an embodiment in which one microchannel branches into multiple microchannels in stages. In this case, it is possible to separate liquids in stages. Figure 4(b) shows an embodiment with a meandering shape. In this case, liquids can be retained in the microchannel for a long period of time, which makes it possible, for example, to maintain reaction times or more uniformly mix two or more substances.

[0058] In the present disclosure, as shown in Fig. 4(c), a placement section S for capturing and placing microparticles, cells, reagents, etc. may be provided midway along the microchannel 14. In this case, a porous substrate may or may not be placed within the placement section. The microchannel may have one placement section or multiple placement sections. The number of arrangement portions is appropriately selected depending on the number of reagents, etc., the application of the microchannel structure, etc. The arrangement position of the arrangement portion is not particularly limited, and can be, for example, the middle position of the microchannel. The shape of the arrangement portion in a plan view is not particularly limited, and examples thereof include a circle, an ellipse, a rectangle, a diamond, a polygon, etc.

[0059] 2. Base material The substrate in the present disclosure is a member that supports the spacer. Examples of materials for the substrate include organic materials and inorganic materials. An example of an organic material is a resin. Examples of resins include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), silicone resins such as polydimethylsiloxane (PDMS), acrylic resins, and epoxy resins. On the other hand, examples of inorganic materials include glass and silicon. When the microchannel structure according to the present disclosure is used as a sensor, it is preferable that at least the surface of the substrate facing the conductor layer be insulating.

[0060] The planar shape of the substrate is not particularly limited and may be any shape, such as rectangular, circular, or elliptical. The thickness of the substrate may be appropriately determined depending on the intended use of the microchannel structure.

[0061] The surface of the substrate on the spacer side may be subjected to a surface treatment or modification treatment. By performing the surface treatment or modification treatment, for example, it is possible to improve adhesion to the conductor layer described below. Examples of surface treatments include corona treatment, UV treatment, and anti-fogging treatment. Examples of modification treatments include modification treatment by coating with a material having a sulfonic acid group.

[0062] 3.Cover material Examples of materials for the cover material in the present disclosure include resin, ceramic, glass, semiconductor, and metal. Examples of the resin include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), vinyl chloride, polystyrene (PS), and polypropylene (PP). The cover material may be either transparent or opaque, with the former being preferred because it allows for visual observation of the introduction and flow of liquid.

[0063] The planar shape of the cover material is not particularly limited, but is preferably a shape that allows a microchannel having a desired structure to be obtained. The cover material may also have an opening, if necessary.

[0064] 4. Spacer The microchannel structure of the present disclosure has a spacer disposed between the substrate and the cover material. By providing a spacer between the substrate and the cover layer, a microchannel for transporting a reagent solution or other liquid can be formed. Examples of the spacer include a spacer (first spacer) having a porous substrate containing an inorganic material and a thermoplastic resin impregnated into the porous substrate, and a spacer (second spacer) that does not include the porous substrate containing the inorganic material. The planar shape of each spacer is not particularly limited, but it is preferable that it be a shape that allows the formation of a microchannel having a desired structure. Furthermore, each spacer may have an opening as necessary.

[0065] (1) First spacer The first spacer has a porous substrate containing the inorganic material described above and a thermoplastic resin impregnated into the voids of the porous substrate. Examples of the thermoplastic resin include polystyrene, polyester, polyvinyl chloride, polyethylene, and polypropylene resins. In the present disclosure, polystyrene and polyester resins are particularly preferred. This is because the thermoplastic resins have chemical resistance and can reduce elution.

[0066] The thermoplastic resin preferably has a melting point in the range of 60°C to 160°C, particularly in the range of 75°C to 120°C. If the melting point of the thermoplastic resin is higher than this range, the heating temperature during heat fusion with the cover material and the substrate becomes too high, which may cause thermal damage to the substrate. Furthermore, the thermoplastic resin may not be sufficiently impregnated into the porous substrate. Furthermore, if the melting point is lower than this range, the thermoplastic resin may be impregnated into areas other than the spacer formation area (for example, the area where the microchannel is formed).

[0067] The melt mass flow rate (MFR) of the thermoplastic resin is not particularly limited, but from the viewpoint of impregnation into the porous layer core material, it is preferably 5 g / 10 min or more, more preferably 15 g / 10 min or more. On the other hand, from the viewpoint of not impregnating into areas other than the spacer formation area of ​​the porous layer core material, it is preferably 150 g / 10 min or less, more preferably 100 g / 10 min or less. The melt mass flow rate (MFR) is a value measured by a method conforming to the provisions of JIS K7210:2014 at a measurement temperature of 190°C and a load of 2.16 kg.

[0068] In the first spacer, only one type of the above-mentioned thermoplastic resins may be used, or two or more types may be mixed and used.

[0069] The first spacer can be formed simultaneously with the formation of the microchannel in which the porous substrate is disposed. The method for forming the first spacer will be described later in "7. First manufacturing method for a microchannel structure containing a reagent (first embodiment)," and therefore will not be described here.

[0070] (2) Second spacer The material of the second spacer is not particularly limited as long as it does not contain a porous substrate containing an inorganic material, and examples thereof include resins. Examples of resins include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), vinyl chloride, polystyrene (PS), and polypropylene (PP). The resin may also be a curable resin such as a photocurable resin or a thermosetting resin. On the other hand, examples of inorganic materials include glass and quartz.

[0071] Examples of methods for forming the second spacer include a method in which a spacer substrate is cut into a desired shape using a plotter or the like with a laser cutter or the like. Another example is a method in which a molding die is prepared and resin molded. Another example is a method in which a curable resin layer of a desired shape is formed by a printing method, and then the curable resin layer is cured by light or heat to form a spacer of a desired shape. When a photocurable resin is used, for example, a method in which the photocurable resin is applied to the surface of a substrate and a spacer of a desired shape is formed by photolithography is used.

[0072] The second spacer may be disposed by bonding a resin sheet of a desired shape to one side of the substrate or one side of the cover material via an adhesive or pressure-sensitive adhesive. Alternatively, a heat-sealing layer may be used to bond the resin sheet to one side of the substrate or one side of the cover material by thermal lamination. The heat-sealing layer may be the same as that conventionally used as a heat-sealing layer.

[0073] Alternatively, double-sided tape may be used as the second spacer. When using double-sided tape, a microchannel may be formed in the double-sided tape by punching or the like, and then the double-sided tape may be attached to one surface of the substrate and one surface of the cover material.

[0074] The second spacer may be integrated with the substrate, and in this case, the materials used may be the same as those exemplified in "2. Substrate" above.

[0075] 5. Other configurations The microchannel structure of the present disclosure typically has two or more openings connected to the microchannel. The shape of the openings is not particularly limited and any shape can be adopted, including rectangular, circular, and elliptical shapes. The size of the openings is not particularly limited. The openings may be inlets for introducing liquids (reagent solutions or specimens).

[0076] When the opening is an inlet, as shown in Figures 5(a) and 5(d), the inlet O1 can be provided in the cover material 12. By forming the inlet in the cover material, it becomes easier to drip liquid into the inlet, and gravity acting on the dripped liquid can pressurize the liquid into the microchannel.

[0077] 5(b) and 5(c), the inlet O1 may be formed on the side surface of the microchannel structure, because in this case, the liquid can be introduced into the microchannel by standing the microchannel structure vertically in a container containing the liquid.

[0078] The openings other than the inlet may be air holes or outlets for discharging to the outside. The openings O2 other than the inlet may be provided in the cover material (FIGS. 5(a) and 5(c)), or may be provided in the end face of the microchannel structure or the spacer (FIGS. 5(b) and 5(d)). Alternatively, they may be provided in the substrate.

[0079] 6.Applications The reagent-containing microchannel structure according to the present disclosure can be used in applications requiring a reaction between a reagent and a liquid delivered to a microchannel, such as a microchannel structure for a testing device utilizing various antigen-antibody reactions, enzyme reactions, etc. In such testing, an optical method or an electrochemical method may be used. The reagent-containing microchannel structure can also be used as a storage container (reservoir) for the reagent.

[0080] The liquid to be used in the microchannels of the present disclosure is not particularly limited and may include, for example, aqueous solutions such as water, pH buffer solutions, Ringer's solution, isotonic solutions, and physiological saline. Also included are solutions in which organic solvents such as alcohols and oils are partially or completely replaced in order to change solubility or to extract into a liquid with a different solubility. Other examples include various specimens and samples other than specimens, such as blood (whole blood), plasma, serum, nasal swabs, pharyngeal swabs, gargle, nasal secretions, urine, saliva, lavage fluids, antibody solutions, and substrate solutions. These may be diluted as needed.

[0081] 7. First manufacturing method of reagent-containing microchannel structure (first embodiment) The reagent-containing microchannel structure of this embodiment can be manufactured by the following method. Fig. 6 is a schematic process diagram showing an example of a method for manufacturing a reagent-containing microchannel structure of this embodiment. As shown in Fig. 6, the method includes a preparatory step (Fig. 6(a)) of preparing a substrate 11, a cover material 12, and a porous substrate 51 containing an inorganic material, and arranging a thermoplastic resin layer 52 containing a thermoplastic resin between the substrate 11 and the porous substrate 51 and between the cover material 12 and the porous substrate 51 (Fig. 6(b)), and a thermocompression bonding step (Figs. 6(c) and 6(d)) of thermocompression bonding the substrate 11, the cover material 12, and the porous substrate 51 together via the thermoplastic resin layer 52. In the preparatory step, the thermoplastic resin layer is disposed in a region that overlaps in plan view with a region where the spacers 13 are formed. The thermocompression bonding step forms a spacer 13 (first spacer 131) having a porous substrate impregnated with a thermoplastic resin, and a microchannel 14 having a porous substrate 15 not impregnated with the thermoplastic resin, thereby producing a microchannel structure. Further, a freeze-drying step is performed in which the porous substrate 15 arranged in the microchannel 14 is impregnated with a reagent solution and freeze-dried, thereby producing a reagent-containing microchannel structure 100 having a reagent-supported substrate in which the freeze-dried formulation R is supported on the porous substrate 15 (FIG. 6(e)).

[0082] According to this method for manufacturing a microchannel structure, by using a porous substrate, the microchannel structure can be manufactured by thermocompression bonding the porous substrate, the substrate, and the cover material via a thermoplastic resin layer, simplifying the manufacturing process. Furthermore, the microchannel manufactured using the porous substrate can have a microchannel height corresponding to the thickness of the porous substrate, making it easy to control the size of the microchannel structure. Each step will be described in detail below.

[0083] (1) Preparation process This step involves preparing a porous substrate containing a substrate, a cover material, and inorganic fibers, and further disposing thermoplastic resin layers between the substrate and the cover material, and between the cover material and the porous substrate. The substrate and the cover material may be the same as those described above in "B. Microchannel structure containing a reagent (first embodiment) 2. Substrate" and "B. Microchannel structure containing a reagent (first embodiment) 3. Cover material," respectively. Examples of the porous substrate include those similar to those described above in "A. Reagent-carrying substrate 1. Porous substrate." The porous substrate can be impregnated with a thermoplastic resin, which will be described later, to form a spacer.

[0084] The thermoplastic resin layer is disposed between the substrate and the porous substrate, and between the cover material and the porous substrate, in an area that overlaps in plan view with the area where the spacer is formed, i.e., in an area other than the area where the microchannel is formed.

[0085] For example, a thermoplastic resin layer may be disposed on both main surfaces of the porous substrate in areas that overlap in plan with the area where the spacers are to be formed (P in FIG. 6). Alternatively, the thermoplastic resin layer may be formed on one surface of the substrate and one surface of the cover material in areas that overlap in plan with the area where the spacers are to be formed.

[0086] The thermoplastic resin layer may be arranged, for example, by forming a dry film made of a thermoplastic resin having openings in the region where the microchannel is to be formed in advance, and then attaching the dry film to both main surfaces of the porous substrate, or to one side of the substrate and one side of the cover material. Another example is a method in which a thermoplastic resin layer is formed on one side of the substrate and one side of the cover material, or on the entire both main surfaces of the porous substrate, a mask is formed in the region where the spacer is to be formed, and the thermoplastic resin layer other than the masked region is removed by etching.

[0087] The thermoplastic resin contained in the thermoplastic resin layer in the present disclosure may be the same resin as that described in "B. Microchannel structure containing reagent (first embodiment) 4. Spacer (1) First spacer" above, and therefore further description here will be omitted.

[0088] (2)Thermocompression bonding process This step involves thermocompression bonding the substrate, the cover material, and the porous substrate together via the thermoplastic resin layer, thereby causing the thermoplastic resin disposed in the spacer-forming region to impregnate the spacer-forming region of the porous substrate, forming a spacer having a porous substrate impregnated with the thermoplastic resin. This also results in the formation of a microchannel having a porous substrate not impregnated with the thermoplastic resin, resulting in a microchannel structure.

[0089] A preferred thermocompression bonding method is a method using a thermal laminator. The thermocompression bonding conditions are, for example, a temperature of 60°C to 250°C, preferably 75°C to 210°C, and a pressure of 0 kg / cm. 2 Larger than 40kg / cm 2 Less than 0.5 kg / cm, preferably 0.5 kg / cm 2 More than 10kg / cm 2 It can be within the following range:

[0090] The above-mentioned "(1) preparation step" and "(2) thermocompression bonding step" may be carried out independently or successively.

[0091] However, the method is not limited to the above, and for example, a method in which one side is supported by a planar support and the other side is pressed with a roll can also be used. In addition, the heat source may be on one side or both sides.

[0092] Alternatively, a laminate may be produced by bonding a substrate (or a cover material) and a porous substrate together with a thermoplastic resin layer interposed therebetween, and then the laminate and the cover material (or substrate) may be bonded together with the thermoplastic resin layer interposed therebetween. In this case, a release material may be provided on the laminate to protect it from scratches and dust during transportation or storage until the next process. In this state, it is also possible to drop a reagent solution onto a portion of the porous substrate and then carry the lyophilized preparation partially thereon by the reagent lyophilization step described below.

[0093] (3) Reagent freeze-drying process This step involves impregnating a porous substrate placed in a microchannel with a reagent solution and freeze-drying the impregnated porous substrate. When the inlet is located on the side of the microchannel structure, the reagent solution can be impregnated into the porous substrate placed in the microchannel by standing the microchannel structure vertically in a container containing the reagent solution. The freeze-drying method can be the same as the method described above in "A. Reagent-carrying substrate 2. Freeze-dried preparation."

[0094] 8. Second manufacturing method of reagent-containing microchannel structure (first embodiment) The reagent-containing microchannel structure of this embodiment can also be manufactured by the following method. FIG. 7 is a schematic process diagram showing another example of a method for manufacturing the reagent-containing microchannel structure of this embodiment. As shown in FIG. 7, for example, one surface of the substrate 11 and one surface of the cover material 12 are opposed to each other and attached via the second spacer 132 described above to produce a microchannel structure having a hollow structure X, a microchannel 14 (FIGS. 7(a) and 7(b)). Then, the reagent-containing microchannel structure 100 can be obtained by placing the porous substrate 15, cut to an appropriate size and carrying the freeze-dried formulation R, in the microchannel (FIG. 7(c)). The porous substrate 15 carrying the freeze-dried formulation R can be prepared by cutting the above-described "A. Reagent-carrying substrate" to an appropriate size.

[0095] As another manufacturing method, a microchannel structure having a microchannel 14 with a hollow structure X as shown in FIG. 7(b) is manufactured, and then a porous substrate cut to an appropriate size is inserted into the microchannel, and then the porous substrate is impregnated with a reagent solution and freeze-dried. As the porous substrate in the present disclosure, the same as "A. Reagent-carrying substrate 1. Porous substrate" can be used.

[0096] C. Microchannel structure containing reagent (second embodiment) The present disclosure provides a reagent-filled microchannel structure comprising: a substrate; a cover material disposed on one surface of the substrate; a spacer disposed between the substrate and the cover material; and a microchannel partitioned by the substrate, the cover material, and the spacer and extending in a direction perpendicular to the thickness direction of the substrate, wherein at least one of the substrate and the cover material is a porous material having a pore size of 2.0 μm or less; and a freeze-dried preparation is immobilized in the microchannel.

[0097] Fig. 8(a) is a schematic plan view showing an example of a microchannel structure according to this embodiment, Fig. 8(b) is a cross-sectional view taken along line AA of Fig. 8(a), and Figs. 8(c) and 8(d) are cross-sectional views taken along line BB of Fig. 8(a). The freeze-dried formulation is omitted from Figs. 8(a) to 8(c), while the freeze-dried formulation R is fully illustrated in Fig. 8(d). The microchannel structure 200 shown in Fig. 8 includes a substrate 11, a cover material 22 that is a porous material with a pore size of 2.0 µm or less and is disposed on one side of the substrate 11, a spacer 13 disposed between the substrate 11 and the cover material 22, and a microchannel 14. The freeze-dried freeze-dried formulation R is immobilized in the microchannel 14.

[0098] The microchannel structure in this embodiment uses a porous material with a pore size of 2.0 μm or less. Such a porous material has a small pore size, which prevents the reagent solution (liquid) from passing through before freeze-drying, but allows only the water vapor (gas) sublimated during freeze-drying to pass through after drying and decompression. If the pore size of the porous material is larger than the above value, the reagent solution before freeze-drying may spray out from the pores in the porous material. If no porous material is used, water vapor enters and exits only through the openings of the microchannel structure, which may cause the reagent to spray out from the openings during or after freeze-drying. This tendency becomes more pronounced when the thermal conductivity within the microchannel is low. When the thermal conductivity is low, it is difficult to heat the reagent solution uniformly when attempting to sublimate the water by heating it under reduced pressure after freezing it, resulting in temperature distribution in the reagent solution. Therefore, when using a porous material with a large pore size exceeding 2.0 μm, problems such as the liquefied reagent solution spraying out in areas where the temperature is partially elevated can occur. On the other hand, if the pore size is 2.0 μm or less, even if the thermal conductivity inside the microchannel is low, only water vapor (gas) can pass through the pores of the porous material, so the drying process can proceed without problems such as the reagent solution spraying out, and the reagent solution can be fixed inside the microchannel by freeze-drying. Furthermore, even if a porous material with a pore size of 2.0 μm or less is used for the cover material, it is possible to use a porous substrate arranged in the microchannel that contains an inorganic material, or a material with a thermal conductivity of 0.5 W m, as in the reagent-containing microchannel structure of the first embodiment described above. -1 ·K -1 If the material meets the above requirements, the water vapor sublimated under reduced pressure can be stably released from the open vent holes in the microchannel within the freeze-dryer profile, and unstable evaporation that would cause the reagent to spray out can be suppressed.

[0099] 1. Porous material The porous material in the present disclosure is preferably used for the cover material, but is not limited to this. A porous material may be used as the substrate, or both the substrate and the cover material may be porous materials.

[0100] The porous material of the present disclosure has voids inside. The pore size of the voids may be 2.0 μm or less, preferably 1.5 μm or less, and more preferably 1.0 μm or less. If the pore size is larger than the above value, the filled reagent may spray out from the pores of the porous material. There is no particular limitation on the lower limit of the pore size of the porous material, but for example, it is preferably 0.01 μm or more, and particularly preferably 0.1 μm or more. If it is smaller than the above value, sufficient drying cannot be performed. In this specification, the "pore size" of the pores of the porous material means the average value of the smallest pore size of the pores in a plane perpendicular to the thickness direction of the porous material (cover material or substrate). The pore size of the pores of the porous material can be measured, for example, using an electron microscope (SEM) or the like.

[0101] The porosity of the porous material is not particularly limited, but is preferably 0.1% or more, and more preferably 0.5% or more. On the other hand, it is preferably 40% or less, and more preferably 10% or less. The porosity of the porous material can be calculated by the method described above in "A. Reagent-carrying substrate."

[0102] Examples of the shape of the porous material include membranes, films, and sheets having a pore size of the above-mentioned specific value or less. The material of the porous material preferably contains a resin. Examples of the resin include fluororesins such as PTFE, PFA, PCTFE, and ETFE, and in the present disclosure, a porous PTFE sheet is particularly preferred. The resin film or sheet may be unstretched or stretched. When the resin is made porous by stretching, the pores typically have a minor axis and a major axis on a surface perpendicular to the thickness direction of the porous material. The porous material may also have a multilayer structure. For example, a porous resin sheet (e.g., a high-pore sheet (porous olefin film, pore size 1.0 μm or less: manufactured by Asahi Kasei Corporation)) having a fluororesin-containing water-repellent coating formed on its surface is inexpensive and can be used advantageously.

[0103] The thickness of the porous material is not particularly limited, but is preferably 10 μm or more, more preferably 30 μm or more, and is preferably 800 μm or less, more preferably 250 μm or less.

[0104] 2. Fixation of freeze-dried formulations The freeze-dried preparation in this embodiment may be immobilized within the microchannel, and may be immobilized on the porous substrate described above or on a porous substrate made of a resin, or may be disposed on the surface of a substrate, a cover material, or a spacer within the microchannel. Since at least one of the substrate and the cover material is made of the porous material described above, freeze-drying is possible within the microchannel even if the thermal conductivity within the microchannel is low, and a microchannel structure containing a reagent can be obtained without any problems.

[0105] 3. Other configurations The substrate, cover material, spacer, microchannel, and freeze-dried preparation in this embodiment are the same as those in "B. Reagent-containing microchannel structure (first embodiment)" above, and therefore will not be described here. Furthermore, the microchannel of the reagent-containing microchannel structure of this embodiment may be provided with the porous substrate described in the above section "B. Microchannel structure containing a reagent (first embodiment) 1. Microchannel (1) Porous substrate".

[0106] 3. Manufacturing method The reagent-containing microchannel structure of this embodiment can also be produced by the following method: For example, it can be produced by a step of making a microchannel structure having a hollow microchannel by placing one surface of a substrate and one surface of a porous cover material opposite each other and attaching them via the second spacer described above, and a freeze-drying step of introducing a reagent solution into the microchannel and freeze-drying the resultant.

[0107] D. Microfluidic Device Containing Reagent (First Embodiment) A reagent-containing microchannel device according to the present disclosure will be described with reference to the drawings. FIG. 9 is a schematic cross-sectional view showing an example of a reagent-containing microchannel device according to the present disclosure. The microchannel device 300 shown in FIG. 9 includes a substrate 11, a cover material 12 disposed on one side of the substrate, a spacer 13 disposed between the substrate 11 and the cover material 12, a microchannel 14 surrounded by the substrate 11, the cover material 12, and the spacer 13, extending perpendicular to the thickness direction of the substrate 11 and transporting a liquid in the extending direction, and a conductor layer 16 disposed on the substrate 11. A porous substrate 15 containing an inorganic material is disposed in the microchannel 14, and the porous substrate 15 carries a freeze-dried formulation R. In FIG. 9, the conductor layer 16 includes an electrode portion 16a and a terminal portion 16b.

[0108] The substrate, cover material, spacer, microchannel, porous substrate, and freeze-dried preparation in the microchannel device of the present disclosure are the same as those in "B. Microchannel structure containing reagent (first embodiment)" described above, and therefore will not be described here.

[0109] In the present disclosure, the conductor layer is preferably a layer having at least an electrode portion and a terminal portion. The electrode portion and the terminal portion are electrically connected, and the two may be connected directly or via a wiring portion.

[0110] The electrode part is usually a component for measuring a current value. Electrodes used in general electrochemical measurements can be used as the electrode part. Examples of materials for the electrode part include metal materials containing stable metal elements such as Au, Pt, Ag, Pd, and Ni, and carbon materials such as glassy carbon, carbon paste, graphite, and diamond-like carbon.

[0111] The conductor layer has one or more electrode parts. Examples of combinations of multiple electrode parts include a combination of a working electrode and a counter electrode (two-electrode system), a combination of a working electrode, a counter electrode, and a reference electrode (three-electrode system), and a combination of two working electrodes, a counter electrode, and a reference electrode (four-electrode system). The planar shape of the electrode part that serves as the working electrode is not particularly limited, but examples include a rectangle and a comb shape. Examples of methods for forming the electrode parts include photolithography, mask vapor deposition, screen printing, gravure printing, flexographic printing, and inkjet printing.

[0112] The terminal portion is a member electrically connected to an external measuring device. The material of the terminal portion can be the same as the material of the electrode portion described above, but metal materials are preferred because they have high conductivity. The material of the terminal portion may be the same as or different from the material of the electrode portion. The terminal portion may be formed simultaneously with the electrode portion or may be formed separately from the electrode portion. The measuring device may be a device used for general electrochemical measurements, such as a potentiostat or a current amplifier.

[0113] The wiring portion is a member that electrically connects the electrode portion and the terminal portion. The material of the wiring portion can be the same as the material of the electrode portion described above, but metal materials are preferable because they have high conductivity. The material of the wiring portion may be the same as or different from the material of the electrode portion. Furthermore, the terminal portion may be formed simultaneously with the electrode portion or separately from the electrode portion.

[0114] The reagent-containing microchannel device according to the present disclosure can be used for various purposes as described above in "B. Microchannel structure containing reagent (first embodiment) 6. Uses", particularly as a testing device.

[0115] E. Microfluidic Device Containing Reagent (Second Embodiment) A reagent-containing microchannel device according to this embodiment will be described with reference to the drawings. FIG. 10 is a schematic cross-sectional view showing an example of a reagent-containing microchannel device according to the present disclosure. The microchannel device 400 shown in FIG. 10 includes a substrate 11, a porous cover material 22 disposed on one side of the substrate, a spacer 13 disposed between the substrate 11 and the cover material 22, a microchannel 14 surrounded by the substrate 11, the cover material 22, and the spacer 13, extending perpendicular to the thickness direction of the substrate 11 and transporting a liquid in the extending direction, and a conductor layer 16 disposed on the substrate 11. A freeze-dried formulation R is immobilized in the microchannel 14. In FIG. 10, the conductor layer 16 includes an electrode portion 16a and a terminal portion 16b.

[0116] The substrate, porous material, cover material, spacer, microchannel, and freeze-dried preparation in the microchannel device of the present disclosure are the same as those in "C. Microchannel structure containing reagent (second embodiment)" above, and therefore their explanations are omitted here. The conductor layer is the same as those in "D. Microchannel device containing reagent (first embodiment)" above, and therefore their explanations are omitted here.

[0117] The microchannel device according to the present disclosure can be used for various purposes as described above in "B. Microchannel structure containing reagent (first embodiment) 6. Uses", particularly as a testing device.

[0118] The present disclosure is not limited to the above-described embodiments. The above-described embodiments are merely examples, and any configuration that is substantially identical to the technical idea described in the claims of the present disclosure and that provides similar effects is included within the technical scope of the present disclosure. [Example]

[0119] The present disclosure will be explained in more detail below with reference to examples.

[0120] (Example 1) Endotoxin sensor A three-layer structure was created by laminating 30 μm thick aluminum foil (Mitsubishi Aluminum Corporation), 450 μm thick glass paper 1 (FAP-50, Olivest Co., Ltd.), and 100 μm thick porous PTFE (polytetrafluoroethylene) (SEF-010, Chukoh Chemical Industry Co., Ltd.), and sterilizing it in an oven at 200°C for 90 minutes. After allowing it to cool to room temperature, 0.5 mL of endotoxin-free Otsuka Water (Otsuka Pharmaceutical Factory Co., Ltd.) was added to one test tube of the LAL freeze-dried reagent (Endospecy ES-24S, Seikagaku Corporation). The solution was then applied in a line to the glass paper underneath the PTFE sheet and allowed to diffuse naturally. The PTFE sheet was replaced, and the three layers were frozen in a freeze dryer. After vacuum drying (5 hours), the air was replaced with dry nitrogen gas and released. The LAL reagent was observed to be encapsulated in the glass paper and re-freeze-dried (reagent-supported substrate).

[0121] The glass paper (reagent-carrying substrate) carrying the reagent was cut to 2 mm x 10 mm, and inserted into and filled into the microchannels of a laminated microchannel device prepared by patterning vapor-deposited metal wiring on a PET sheet, as described in JP 2019-52921 A, to obtain a reagent-containing microchannel device (endotoxin sensor) according to the present disclosure.

[0122] An endotoxin test was performed using the resulting endotoxin sensor. Specifically, a Japanese Pharmacopoeia endotoxin standard was prepared in a buffer solution at 0.005, 0.01, and 0.02 EU / mL, a calibration curve (current value vs. endotoxin concentration curve) was created, and a voltage of 0.5 V was applied to a potentiostat (MAS) to measure the corresponding current value. This sensor showed endotoxin test results equivalent to those obtained after storage at 4°C for 3 months in a nitrogen-filled aluminum bag.

[0123] Example 2 5-mm-wide, 70-μm-thick styrene-based elastomer films were bonded at 5-mm intervals to both sides of a 200-μm-thick glass paper (Glass Paper 2, Model No. SMK-025, manufactured by Olivest Co., Ltd., volume porosity 90%). This was then placed between two 100-μm-thick PET sheets (Cosmoshine, manufactured by Toyobo Co., Ltd.) serving as a substrate and cover material, and the sheets were heat-sealed to produce a microchannel structure with a total thickness of 420 μm and a simulated channel with a channel height of 220 μm and a channel width of 5 mm. This was cut into 30-mm pieces to form a microchannel structure with openings at both ends (double-open type). Glucose oxidase (GLO-201, manufactured by Toyobo Co., Ltd.) was dissolved in a 50 mM Tris-HCl (manufactured by Junsei Chemical Co., Ltd.) aqueous solution at pH 7.2 at a concentration of 50 units / mL, filled into the channels, frozen in a freeze dryer, and dried for 25 hours to obtain a reagent-filled microchannel structure (first embodiment) according to the present disclosure.

[0124] Example 3 A microchannel structure with open ends was fabricated in the same manner as in Example 2, except that the PET sheet (cover material) on one side of the flow channel device of Example 2 was replaced with a 100 μm thick porous PTFE (polytetrafluoroethylene) sheet (Siporus (registered trademark) SEF-010: pore size (average minor axis of pores in a plane perpendicular to the thickness direction) 0.7 μm, manufactured by Chukoh Chemical Industry Co., Ltd.) as the cover material. A glucose oxidase solution was filled into the flow channel and freeze-dried to obtain a reagent-filled microchannel structure (first embodiment and second embodiment) according to the present disclosure.

[0125] (Comparative Example 1) A 70 μm thick styrene elastomer film (spacer) (40% opening, 0.7 mm diameter porous: Meiwa Gravure Co., Ltd.) was bonded to both sides of a 100 μm thick PET sheet core (Cosmoshine: manufactured by Toyobo Co., Ltd.) to form a 5 mm width. This was placed between two 100 μm thick PET sheets (Cosmoshine: manufactured by Toyobo Co., Ltd.) with a 5 mm gap between them and bonded with heat sealing to produce a microchannel structure with a total thickness of 420 μm, containing simulated channels with a channel height of 220 μm and a channel width of 5 mm, separated by spacers. This was cut to a length of 30 mm to form a microchannel structure with openings on both ends (open-ended type). Glucose oxidase (GLO-201: manufactured by Toyobo Co., Ltd.) was dissolved in a 50 mM Tris-HCl (manufactured by Junsei Chemical Co., Ltd.) pH 7.2 aqueous solution at a concentration of 50 units / mL, filled into the channel, frozen in a freeze dryer, and dried for 25 hours.

[0126] Example 4 A microchannel structure with open ends was fabricated in the same manner as in Comparative Example 1, except that the PET sheet (cover material) on one side of the microchannel structure of Comparative Example 1 was replaced with a porous material, 100 μm thick porous PTFE (polytetrafluoroethylene) (SEF-010: manufactured by Chukoh Chemical Industry Co., Ltd.), and a glucose oxidase solution was filled into the channel and freeze-dried to obtain a reagent-filled microchannel structure (second embodiment) of the present disclosure.

[0127] [Observation of reagent spraying] When the 10 flow path devices each of Examples 2 to 4 and Comparative Example 1 were observed for reagent spraying, spraying of frozen reagent was observed in 9 out of 10 flow path devices of Comparative Example 1, but no spraying was observed in Examples 2 to 4. Furthermore, when the temporarily attached PTFE sheet was peeled off, a PET sheet (covering material) was placed on top, and a 4 mm wide line of thermal lamination was performed on the thermal lamination sheet, readhesion was confirmed.

[0128] Example 5: Preparation of a glucose sensor Glass paper (FAP-50, manufactured by Olivest) was wrapped in aluminum foil and dry-heat sterilized at 200°C for 90 minutes. A vapor-deposited film containing Pd was formed on one side of the PET sheet substrate. Next, a positive photosensitive resist layer was formed on the Pd layer, exposed using a photomask, and then developed to form a resist pattern. Next, the Pd layer exposed from the resist pattern was removed by etching, and the resist pattern was peeled off. This resulted in the formation of a conductor layer having electrode portions, terminal portions, and wiring portions. The microfluidic device shown in Figure 9 was fabricated in the same manner as in Example 2, except that the substrate on which this conductor layer was formed and the dry-heat sterilized glass paper were used. An air vent hole (opening O2) was provided above the sensor detection electrode portion in the PET sheet cover material.

[0129] Ten microliters of a 50 mM Tris-HCl (Junsei Chemical Co., Ltd.) pH 7.2, 20 mM potassium chloride (Junsei Chemical Co., Ltd.), and 100 mM potassium ferricyanide (Junsei Chemical Co., Ltd.) aqueous solution was applied from the sample application side (opening O1 in Figure 9). 20 μL of a 50 unit / mL glucose oxidase (GLO-201: Toyobo Co., Ltd.) aqueous solution was also applied from the air vent hole, and the solution was applied to glass paper and freeze-dried to prepare a glucose sensor.

[0130] Blood glucose levels were measured using the fabricated sensor at a current value of 0.5 V using a potentiostat (MAS). Samples used were blood collected from the fingertip and blood to which glucose (Junsei Chemical Co.) had been added (52 mg / dL whole blood, 98 mg / dL whole blood, and 200 mg / dL adjusted blood, with blood glucose levels confirmed using a commercially available blood glucose meter, One Touch Ultra, and an LFS sensor (LifeScan)), and the corresponding current values ​​were obtained.

[0131] (Examples 6 to 10, Comparative Examples 2 to 5) A microchannel structure was obtained using the cover material and core material shown in Table 1. Three types of cover material were used: a PET sheet, a 50 μm thick, 1.5 mm square diamond-shaped hole poly sheet with an opening ratio of 7% (manufactured by Shin-Nihon ALC Industries Co., Ltd.), and a 100 μm thick porous PTFE sheet (Siporus (registered trademark) SEF-010: pore size (average minor axis of pores on a surface perpendicular to the thickness direction) 0.7 μm, manufactured by Chukoh Chemical Industry Co., Ltd.). The core material was a 200 μm thick glass paper (Glass Paper 2, model number SMK-025, manufactured by Olivest Co., Ltd., with a volume porosity of 90% and a thermal conductivity of 1.0 W·m -1 ·K -1 In addition to the above, a 160 μm thick PP nonwoven fabric sheet (PP spunbond, manufactured by Toray Industries, Inc.) and a PET sheet for forming a hollow structure were used, and similarly to Example 2 and Comparative Example 1, 9 types of microchannel structures for hollow or fiber-filled microchannel devices, 10 each, were fabricated using a base sheet, a core material, a cover sheet, and a heat-melting resin film for welding them. This was cut to a length of 30 mm to make it open at both ends, and glucose oxidase (GLO-201: manufactured by Toyobo Co., Ltd.) was dissolved in a 50 mM Tris-HCl (manufactured by Junsei Chemical Co., Ltd.) pH 7.2 aqueous solution at a concentration of 50 units / mL, filled into each channel, frozen in a freeze dryer, and dried for 25 hours. Table 1 shows the number of samples (out of 10) in which reagent spraying was observed.

[0132] [Table 1]

[0133] As can be seen from the results in Table 1, the enzyme solution was refrozen in all microchannel structures, but in all structures except those in which a porous PTFE sheet was used as the cover material (Examples 8 to 10) and those in which glass paper was used as the filler in the channel (Examples 6 to 8), some of the contents were observed to spray out during freeze-drying at the locations (cover material and opening) and frequencies shown in the table. [Explanation of symbols]

[0134] 1, 15 … Porous base material 10... Reagent-carrying substrate 11 … Base material 12... Cover material 13...Spacer 14... Microchannel 22 … Porous material (cover material) 100, 200... Microchannel structure containing reagent 300, 400... Microfluidic device containing reagents

Claims

1. A substrate; A cover material disposed on one surface side of the substrate; a spacer disposed between the substrate and the cover material; a microchannel defined by the substrate, the cover material, and the spacer and extending in a direction perpendicular to a thickness direction of the substrate; At least one of the substrate and the cover material is a porous material having a pore size of 2.0 μm or less, the porous material is a porous PTFE sheet, The thermal conductivity of the porous material is 0.5 W m ―１ ・K －１ That's all, A reagent-containing microchannel structure, wherein a freeze-dried preparation is immobilized in the microchannel.

2. A substrate; A cover material disposed on one surface side of the substrate; a spacer disposed between the substrate and the cover material; a microchannel defined by the substrate, the cover material, and the spacer and extending in a direction perpendicular to the thickness direction of the substrate; a conductor layer disposed on the substrate in a region where the microchannel is formed, At least one of the substrate and the cover material is a porous material having a pore size of 2.0 μm or less, the porous material is a porous PTFE sheet, The thermal conductivity of the porous material is 0.5 W m ―１ ・K －１ That's all, A reagent-containing microchannel device, in which a freeze-dried preparation is immobilized in the microchannel.

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