Analysis device and method for inspecting analysis device

Abstract

To provide an analysis device that can maintain stability of a dispensed sample in a dispensation part while protecting a surface, and can perform stable measurement.SOLUTION: An analysis device has a hydrophilic or porous channel area that is surrounded by a hydrophobic channel wall provided inside or on a substrate. The analysis device is provided, on its surface, with a dispensation part in which a sample is dispensed, an area B that is provided to surround the dispensation part and covered by a regulation member not permeated with the specimen, and an area A that is formed adjacent to a side of the area B not facing the dispensation part. The boundary between the area A and the area B is provided with a step in a thickness direction of the analysis device, and the step satisfies requirements (i) or requirements (ii). (i) The area A is lower than the area B. (ii) The area A is higher than the area B and the area A is covered by the regulation member not permeated with the sample.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an analytical device having a hydrophilic or porous flow channel region surrounded by hydrophobic flow channel walls provided in or on a substrate. [Background technology]

[0002] In recent years, analytical devices that utilize small-sized microchannels to efficiently perform biochemical analysis on a single chip have been attracting attention in a wide range of fields, including biochemical research, medicine, drug discovery, healthcare, the environment, and food.

[0003] In the early 1990s, photolithography and molds were used to form micrometer-sized fine channels on glass or silicon, and analytical devices were developed that could perform sample pretreatment, stirring, mixing, reaction, and detection on a single chip. As a result, miniaturization of testing systems, rapid analysis, and reduction of specimens and waste liquids were realized.

[0004] Electrochemical analysis, which measures the potential between electrodes immersed in the sample to be analyzed, is widely used in fields such as medicine and the environment. Conventional electrochemical analysis is performed by technicians using sophisticated equipment, which limits the fields and resources available for measurement. Therefore, there is a need for inexpensive, easy-to-use, disposable electrochemical analysis devices for use in developing countries and depopulated areas with insufficient medical facilities, medical care at disaster sites, and airports where the spread of infectious diseases must be prevented at the border.

[0005] Non-Patent Document 1 proposes a filter paper-based measurement device for measuring sodium and potassium ion concentrations. This device has a dispensing section for dispensing the sample. The dispensed sample permeates from the dispensing section into the working and reference electrode regions, electrically connecting the two electrodes and enabling potential difference measurement. To achieve a stable potential at the reference electrode, the device deposits KCl ion crystals on the reference electrode. During measurement, KCl dissolves in the sample, maintaining a high concentration of Cl ions in the reference electrode region and achieving a stable reference electrode potential. Furthermore, an ion-selective membrane formed to cover the working electrode selects only the ions to be measured, allowing measurement to be performed without being affected by other ions.

[0006] Patent Document 1 also discloses a method for measuring the concentration of a specific protein contained in a biological sample. A fluorescent substance is placed in a sensing area defined by a hydrophobic barrier formed on a paper substrate, and the concentration of the specific protein is measured by analyzing the fluorescent signal generated by reaction with the sample. It is stated that the sensing area formed by the hydrophobic barrier and the biological sample dispensing section may be the same area.

[0007] Furthermore, Patent Document 2 proposes a configuration in which the sensing area and the sample dispensing section are the same area to improve measurement sensitivity, and the sample dispensing section is covered with a restricting member that prevents the sample from penetrating around it so that the sample is dispensed only to the required area. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent No. 6415827 [Patent Document 2] Japanese Patent Publication No. 2023-48923 [Non-patent literature]

[0009] [Non-Patent Document 1] Nipapan Ruecha, Orawon Chailapakul, Koji Suzuki and Daniel Chitterio “Fully Inkjet-Printed Paper-Based Potentiometric Ion-Sensing Devices” Analytical chemistry August 29, 2017 Published, 89, pp.10608-10616 Summary of the Invention [Problem to be solved by the invention]

[0010] However, with the above-mentioned configuration, when a sufficiently large amount of sample is dispensed into the dispenser, the sample may spread over the restricting member, making it impossible to retain a sufficient amount of sample in the dispenser.Furthermore, when the device is transported after dispensing, the sample may flow out of the dispenser due to the impact of transportation. Therefore, it is necessary to retain a sufficient amount of sample in the dispensing section so that the measurement is not affected even if there is an impact during transportation.

[0011] An object of the present invention is to stably maintain the sample dispensed into the dispenser portion in the vicinity of the dispenser portion in the above analytical device. [Means for solving the problem]

[0012] The present invention provides an analytical device having a hydrophilic or porous flow path region surrounded by hydrophobic flow path walls disposed within or on a substrate, comprising: The surface of the analytical device is a dispensing unit into which the sample is dispensed; an area B that is adjacent to the periphery of the dispensing section and is provided so as to surround the dispensing section, and is covered with a restricting member that is impermeable to the sample; an area A formed adjacent to the area B on a side not facing the dispensing portion; is established, The analytical device is characterized in that a step is provided in the thickness direction of the analytical device at the boundary between the region A and the region B on the surface of the analytical device, and the step satisfies either the following requirement (i) or (ii): (i) The area A is lower than the area B. (ii) The region A is higher than the region B, and the region A is covered with a restricting member that is impermeable to the sample. The present invention also provides a testing method for a sample using the above analytical device, wherein the boundary between the region B and the region A is included in the range in which the sample spreads when the sample is dispensed. [Effects of the Invention]

[0013] As described above, according to the present invention, it is possible to provide a microchannel device that can protect the surface of the device while maintaining the stability of the dispensed sample in the dispenser, thereby enabling stable measurements. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a top view showing the configuration of an analytical device P1 according to Example 1. FIG. [Figure 2] FIG. 2 is a simplified view showing a CC′ cross section of the analytical device P1 shown in FIG. [Figure 3] 1 is a schematic diagram of an analytical device P1 in Example 1 in which a sample is dispensed. FIG. [Figure 4] FIG. 10 is a top view showing the configuration of an analysis device P2 according to a second embodiment. [Figure 5] 1 is a diagram showing the shapes of a regulating member 11, a regulating member cutout portion 12, and a regulating member cutout portion 13 in the vicinity of a dispensing portion according to Examples 1 and 2. FIG. [Figure 6] FIG. 10 is a top view showing the configuration of an analysis device P3 according to a third embodiment. [Figure 7] FIG. 10 is a schematic cross-sectional view of an analytical device P3 according to Example 3. [Figure 8]FIG. 10 is a top view showing the configuration of another form of the analysis device P3 according to the third embodiment. [Figure 9] 10 is a schematic cross-sectional view of another configuration of the analytical device P3 according to Example 3. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0015] The analytical device of the present invention is an analytical device having a hydrophilic or porous flow path region surrounded by hydrophobic flow path walls provided inside or on a substrate, and is characterized in that the surface of the analytical device is provided with: a dispensing section into which the sample is dispensed; an area B adjacent to the periphery of the dispensing section, provided so as to surround the dispensing section and covered with a regulating member that is impermeable to the sample; and an area A formed adjacent to the side of area B that is not facing the dispensing section, and the surface of the analytical device is provided at the boundary between area A and area B in the thickness direction of the analytical device, and the step satisfies either of the following requirements (i) or (ii). (i) The area A is lower than the area B. (ii) The region A is higher than the region B, and the region A is covered with a restricting member that is impermeable to the sample.

[0016] Furthermore, the testing method of the present invention is a testing method using the above-mentioned analytical device, characterized in that when the sample is dispensed, the boundary between the area A and the area B is included in the range in which the sample spreads.

[0017] In the present invention, the terms "dispensing section," "area B," and "boundary between area A and area B" refer to the area on the surface of the analytical device where the sample spreads.

[0018] The dispensing section, area B, and the boundary between area A and area B according to the present invention will be described in detail in Examples 1 to 3 below, but when the amount of sample is large, the sample may wet and spread into area A (see Figure 9(c)). [Example]

[0019] Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. Note that the following embodiments are merely examples, and the present invention is not limited to the contents of the embodiments. Furthermore, in the following drawings, components that are not necessary for explaining the embodiments are omitted from the drawings. The analytical device according to the present invention has a hydrophilic or porous flow channel surrounded by hydrophobic flow channel walls provided inside or on a substrate.

[0020] [Example 1] <Flow path configuration> The analytical device P1 according to the first embodiment will be described with reference to FIGS. 1 and 2, which are schematic diagrams. FIG. 1 is a simplified top view of the analytical device P1. FIG. 2 is a simplified view showing the CC′ cross section of the analytical device P1 shown in FIG.

[0021] The analytical device has a hydrophilic or porous flow channel region surrounded by hydrophobic flow channel walls provided inside or on a substrate. A flow channel pattern is formed in the porous substrate and has flow channel chamber 1, flow channel chamber 2, and flow channel 3. Flow channel 3 connects flow channel chamber 1 and flow channel chamber 2.

[0022] A reference electrode 7 is placed in the flow channel chamber 1. The top and side surfaces of the reference electrode 7 are covered with ionic crystals 10. The reference electrode 7 has a lead wire that extends continuously from inside the flow channel chamber 1 onto the flow channel wall 5 as a contact point during measurement.

[0023] A working electrode 8 is disposed in the flow channel chamber 2. The top and side surfaces of the working electrode 8 are covered with an ion-selective membrane 9 containing a component with ion selectivity. The working electrode 8 has a lead wire that continuously extends from inside the flow channel chamber 2 onto the flow channel wall 5. A dispensing unit 6 that dispenses the sample will be described later.

[0024] In Example 1, a hydrophobic resin was placed on a porous paper substrate with a thickness L1 of 0.1 mm and a porosity of 50%, and then thermally fixed to form a flow path pattern as a flow path wall 5 that was impermeable to samples.

[0025] In this example, a paper substrate was used as the porous substrate, but the porous substrate is not limited to paper. The porous substrate may be any material that generates capillary action in a liquid, and may have a porous structure such as open cells or nanofibers inside, or a mesh-like structure. Alternatively, resin, glass, an inorganic substrate, fabric, metal paper, etc. may be used.

[0026] In this embodiment, the flow path pattern is formed by applying a hydrophobic resin and then thermally fixing it, but the present invention is not limited to this. Any method may be used as long as the flow path pattern can be formed, such as by cutting a porous paper substrate to leave only the flow path shape, or by forming the flow path walls with a wax printer.

[0027] <Electrode formulation> The electrode formulation according to Example 1 will be explained with reference to FIG. A reference electrode 7 using Ag / AgCl was provided in the flow channel chamber 1. 1.8 mg of KCl ion crystals 10 were placed on the reference electrode 7.

[0028] On the other hand, a working electrode 8 made primarily of carbon is provided in the flow channel chamber 2. Note that instead of the carbon electrode, an electrode 8 made of a conductive polymer such as PEDOT:PSS (a dispersion of polyethylenedioxythiophene and polystyrene sulfonic acid) may be used. Also, a material such as Ag / AgCl, which has traditionally been used as the base of a reference electrode, may be used.

[0029] A Na ion selective membrane 9 was formed so as to cover the working electrode 8. The ion selective membrane 9 was made of the following material. Ion-selective material bis(12-crown-4) [Bis(12-crown-4)] 3.0wt% Potassium tetrakis(4-chlorophenyl)borate as an anion scavenger 0.5wt% o-nitrophenyl octyl ether 64.0wt% Polyvinyl chloride 32.5wt% In this example, the reference electrode 7, the working electrode 8, and the ion selective membrane 9 are formed in the shapes, sizes, and materials described above, but are not limited to these.

[0030] The material of the ionic crystal 10 is not limited to KCl ionic crystals as long as it contains Cl ions. The mass of the ionic crystal 10 to be placed is not limited to this, but is within the range of mass that results in a saturated solution when the KCl ionic crystal is dissolved in pure water with a volume equivalent to the volume of the flow channel chamber 1.

[0031] Furthermore, when measuring the total amount of ions in a sample, the ion selective membrane 9 is not necessarily required.

[0032] <Shape of dispensing part and dispensing method> This will be explained using Figures 1 and 2. In this embodiment, the dispensing section 6 shown in Fig. 1 is a region on the exposed surface X of the ion selective membrane 9 shown in Fig. 2. The exposed surface X is formed by a circle with a diameter of 4 mm centered at the center of the working electrode 8, and its area is approximately 12.6 mm 2 is. Furthermore, a restricting member 11 is provided to prevent the sample from coming into contact with areas other than the dispensing section, and a restricting member cutout portion 12, which is a cutout portion of the restricting member 11, is provided near the dispensing section 6.

[0033] Here, region A refers to the region on the surface of the analytical device cut out as the restriction member cutout portion 12 in the restriction member 11, and region B refers to the region on the restriction member 11 adjacent to the dispensing portion 6 and sandwiched between region A. In this case, region A is positioned opposite the dispensing portion with region B in between.

[0034] For example, a laminate film made of PET (polyethylene terephthalate) can be used as the regulating member 11. In this embodiment, a laminate film made of PET with a thickness of 50 μm is used.

[0035] The dispensing part 6 has a width of φ5 mm from the center of the working electrode 8, and this part is not covered by the restricting member 11. The restricting member cutout part 12 is formed in a doughnut shape by cutting out the restricting member 11 with an inner diameter of φ7.5 mm and an outer diameter of φ9.5 mm.

[0036] Therefore, by dispensing the specimen onto the exposed surface X, it can be brought into sufficient contact with the ion selective membrane 9 over a wide contact area, and the specimen does not come into contact with the substrate in areas other than the dispensed area.

[0037] In order to dispense a sufficient amount of specimen onto the ion selective membrane 9, the specimen is dispensed with a contact area larger than the area of ​​the dispensing part 6. The specimen dispensed here is in an amount that touches the boundary between region A and region B, as shown in FIG. 3(d).

[0038] <Sample penetration> The permeation of the sample will now be described. After the sample is dispensed onto the exposed surface X shown in Figure 2, ions contained in the sample and selected by the ion selective membrane 9 permeate toward the working electrode 8. In parallel with this permeation, the sample spreads over the exposed surface X, comes into contact with the porous substrate present around the ion selective membrane 9, permeates into the porous substrate, and then, by capillary action, permeates into the flow channel 3 and the flow channel chamber 1 in that order. While the sample permeates the flow channel chamber 1, ions contained in the sample in contact with the exposed surface X are selected by the ion selective membrane 9, and the measurement potential of the working electrode 8 required for measuring the electrolyte concentration is stabilized.

[0039] <Measurement of sample concentration> The measurement of analyte concentration will now be described. 2 by capillary action and reaches the KCl ion crystals 10 covering the reference electrode 7, the KCl ion crystals 10 dissolve in the sample, and the Cl ion concentration in the solution in the flow channel chamber 1 becomes saturated. At this time, if the measurement potential of the working electrode 8 is stable, the sample concentration can be measured, and the measurement of the sample concentration is completed after a predetermined measurement time has elapsed.

[0040] In this embodiment, "ion selection by the ion selective membrane" and "permeation of the specimen into the reference electrode" proceed in parallel, so that the working electrode potential is likely to be stable when the specimen reaches the reference electrode 7.

[0041] In this example, the case where exposed surface X is the dispensing section 6 has been described. If the dispensed volume of the sample is equal to or greater than the volume that can reach flow channel chamber 1 via the upper part of exposed surface X, flow channel chamber 2, and flow channel 3, a sufficient amount of sample can be brought into contact with ion selective membrane 9, and the sample concentration can be measured with good accuracy between the working electrode and the reference electrode.

[0042] [Comparative Example 1] In order to explain the effects of Example 1 in more detail, Comparative Example 1 will be presented. <Flow path configuration and dispenser shape> The shape of the flow path wall of the analytical device was the same as in Example 1. The configurations of the reference electrode, working electrode, ion selective membrane, etc. were also the same as in Example 1. However, the restricting member 11 was configured so that only the dispensing portion was exposed.

[0043] [Effects of Example 1] [Advantages of Example 1 over Comparative Example 1] The advantages of Example 1 over Comparative Example 1 will be described. FIG. 3 is a schematic diagram showing the dispensing process into the analytical device P1.

[0044] 3(a) shows the state immediately after dispensing onto the ion selective membrane 9 in Comparative Example 1. Here, the sample tends to remain in the dispensing portion due to surface tension, but when the amount of sample is large, the sample spreads onto the restricting member 11 due to the wettability relationship between the sample and the restricting member 11, as shown in FIG.

[0045] 3(c) shows the case where the specimen is dispensed off-center from the ion selective membrane 9. In this case, in terms of the wettability relationship between the specimen, the ion selective membrane 9, and the restricting member 11, if the restricting member 11 has better wettability than the ion selective membrane 9, the specimen will flow from the ion selective membrane 9 toward the restricting member 11.

[0046] Furthermore, even if the dispenser is in the state shown in Figure 3(b), if the tip is transported after dispense, the sample may move due to inertia caused by acceleration, or the sample may move due to inertia during deceleration or the impact of stopping, resulting in the state shown in Figure 3(c).

[0047] 3(d) shows the configuration of Example 1. In the configuration of Example 1, by providing restricting member cutout portion 12 around the dispensing portion, during sample dispensing, the wetted and spread dispensed sample is pinned at the boundary between area A and area B, i.e., the boundary between restricting member 11 and restricting member cutout portion 12. This pinning effect makes it possible to suppress the wet spreading of the sample, and to keep the sample in the dispensing portion.

[0048] In this example, it was confirmed that the effect could be obtained if the width of region B was 1.0 mm to 1.5 mm, region A was 50 μm lower than region B (step 50 μm), and the width was 1.0 mm or more.

[0049] Therefore, in contrast to Comparative Example 1, which does not have any special structure on the regulating member near the dispensing section, Example 1 provides a structure around the dispensing section that pins the sample, making it possible to retain the sample in any position, and by maintaining a sufficient amount of sample in the dispensing section even during measurement, stable measurement becomes possible.

[0050] [Example 2] The following describes the analytical device P2 in Example 2. In this example, only the differences from Example 1 will be described, the same members will be given the same reference numerals, and the description of similar parts will be omitted.

[0051] FIG. 4 is a top view showing a schematic configuration of the analysis device P2. FIG. 5(a) shows the shape of the restricting member 11 near the dispensing unit 6 as viewed from above in Example 1, and FIG. 5(b) shows the shape of the restricting member 11 near the dispensing unit 6 as viewed from above in Example 2.

[0052] 5(b), in this example, the restricting member cutout portions 13 provided in the restricting member 11 are discontinuous, that is, portions of the restricting member 11 are not cut out locally, and the restricting member 11 covers the working electrode 8. In contrast to the restricting member cutout portions 12 in Example 1, in Example 2, the donut-shaped restricting member cutout portions 12 are formed such that the restricting member 11 remains at equal intervals at three positions, each corresponding to an angle of 20°. In other words, the restricting member cutout portions 13 are provided at three positions at equal intervals, each corresponding to an angle of 100°.

[0053] [Advantages of Example 2 over Example 1] The advantages of the second embodiment over the first embodiment will be described. In Example 1, as shown in FIG. 5(a), the restricting member cutout portion 12 is continuous, so that a part of the working electrode 8 is exposed from the cutout portion.

[0054] Incidentally, when dispensing a sample, if the sample comes into direct contact with the exposed working electrode 8 due to, for example, unintentional scattering, the sample comes into direct contact with the electrode without passing through the ion selective membrane 9, and the desired results may not be obtained. Therefore, it is desirable that the working electrode 8 is not exposed so that the sample does not come into contact with it. Therefore, in this embodiment, the restriction member cutout portion 12 in the first embodiment is made discontinuous to form a restriction member cutout portion 13 so that the restriction member 11 remains on the working electrode 8 .

[0055] Here, in the portions without cutouts, i.e., between adjacent cutout portions 13 of the restricting member, the specimen attempts to wet and advance on the restricting member 11, but the wetting and spreading of the specimen is suppressed by the surface tension of the specimen and the pinning effect of the cutout portions 13 of the restricting member. Here, if the distance between the restricting members 11 between adjacent cutout portions 13 of the restricting member is equal to or less than a certain width, the surface tension of the specimen can suppress the spreading of the droplet itself.

[0056] In the configuration of this embodiment, fetal bovine serum (hereinafter referred to as "FBS") is used as the sample and PET is used as the regulating member 11. Here, the wetting and spreading is determined by the wetting relationship between the ion selective membrane 9 and the FBS and PET. In this embodiment, the gap between adjacent regulating member cutout portions 13 is at an angle of 20° with the dispensing portion as the center, but this angle is not limited to this depending on the sample and the material of the regulating member 11.

[0057] Therefore, even if notches are not provided around the entire circumference of the restricting member 11 near the dispensing section as in Example 1, the restricting member 11 is left to protect the areas that need to be covered to prevent contamination by unintended impurities, such as scattering of the sample during dispensing. By providing notches in other areas, it becomes possible to retain the sample in any position, and a sufficient amount of sample can be maintained in the dispensing section even during measurement, enabling stable measurement.

[0058] [Example 3] The following describes the analytical device P3 in Example 3. In this example, only the differences from Example 1 will be described, the same members will be given the same reference numerals, and the description of similar parts will be omitted. FIG. 6 is a top view showing a schematic configuration of the analysis device P3. FIG. 7 is a cross-sectional view of the dispensing section of the analytical device P3 shown in FIG.

[0059] In this embodiment, a step is provided on the regulating member 11 by attaching a further regulating member 14 on the regulating member 11 near the outer periphery of the dispensing part 6 .

[0060] 7(a), area A is the area on the regulating member 14, and area B is the area on the regulating member 11 sandwiched between the dispensing unit and area A. In this case, area A is positioned opposite the dispensing unit, with area B sandwiched between them.

[0061] As in Example 1, the dispensing part 6 has a width of φ5 mm from the center of the working electrode 8, and this portion is not covered by the restricting member 11. In addition, by providing a restricting member 14 with an opening having an inner diameter of φ7.5 mm from the center of the dispensing part 6 on the restricting member 11, a structure higher than the restricting member 11 (a step in the thickness direction of the analytical device) is formed, as shown in Figure 7(a). Here, the restricting member 14 uses a PET laminate film with a thickness of 50 µm, the same as the restricting member 11.

[0062] [Effects of Example 3] When a sufficient amount of sample is dispensed into the dispensing section 6, the sample spreads from the dispensing section to wet area B, but as shown in Figure 7(b), the presence of the restricting member 14 allows the sample to be pinned by the edge of the inner circumference of the restricting member 14, thereby retaining the sample in the dispensing section.

[0063] 7(c), by stacking a restricting member 15 with a hole of an even larger outer diameter on the restricting member 14 of FIG. 7(a) (the step is formed in a staircase shape by region B and region A which is one or more steps higher than region B), even if the amount of sample that arrives exceeds the pinning effect at the edge of FIG. 7(a) and the sample spreads over the edge and wets the restricting member 14, the sample will be pinned at the edge of the inner periphery of the restricting member 15. Increasing the number of points at which the sample is pinned in this way makes it possible to firmly hold the sample in the dispensing section.

[0064] 8 and 9(a), a structure taller than the restriction member 11 may be formed by providing the restriction member 14 on the restriction member 11 with an inner diameter of 7.5 mm and an outer diameter of 9.5 mm from the center of the dispensing portion. In this structure, as shown in FIG. 9(b), the sample is first pinned at the inner edge of the restriction member 14 as described above. If an amount of sample dispensed exceeds this pinning effect, the sample will wet and spread over the restriction member 14, which is region A, as shown in FIG. 9(c). When the sample reaches the outer edge of the restriction member 14, a pinning effect similar to that in Example 1 is achieved. Therefore, in this example, the sample can be pinned at two points: the inner edge and the outer edge of the restriction member 14.

[0065] Although the flow channel of the present invention has been described as an example of a flow channel surrounded by a flow channel wall formed of a hydrophobic resin disposed inside a porous substrate, the flow channel may also be a flow channel using a hydrophobic sheet such as PET as the substrate and having its surface rendered hydrophilic by plasma treatment, corona discharge treatment, or surface coating with a hydrophilic polymer. Examples of hydrophilic polymers that can be used include polyethylene glycol (PEG), EVAL (EVOH), poval (PVOH), and polymers containing phosphorylcholine groups. A coating layer formed by applying and drying a liquid blend consisting of hydrophilic inorganic fine particles, polymer fine particles dispersed in an aqueous medium, and a reactive organic fluorine compound may also be used. The hydrophilicity of the flow channel allows the analyte to migrate. Furthermore, by providing a restricting member such as that of the present invention on the flow channel so as to have a gap between the flow channel and the restricting member, capillary action due to the gap between the flow channel and the restricting member can also be added, thereby accelerating the analyte migration. Alternatively, a hydrophobic sheet may be used as the substrate, and a flow path made of a porous material may be provided on the surface of the sheet. The flow path of the present invention may be any hydrophilic or porous flow path surrounded by a hydrophobic flow path wall provided inside or on the substrate.

[0066] <Summary> As described above, by providing a notch in the regulating member 11 or by stacking additional regulating members to create a height difference, it is possible to pin the sample and retain the sample in the dispensing section even if it is subjected to impact during transportation, etc., thereby making it possible to provide a microchannel device that can perform stable measurements.

[0067] The disclosure of this embodiment includes the following configurations and methods. [Configuration 1] An analytical device having a hydrophilic or porous flow path region surrounded by hydrophobic flow path walls disposed within or on a porous substrate, The surface of the analytical device is a dispensing unit into which the sample is dispensed; an area B that is adjacent to the periphery of the dispensing section and is provided so as to surround the dispensing section, and is covered with a restricting member that is impermeable to the sample; an area A formed adjacent to the area B on a side not facing the dispensing portion; is established, An analytical device characterized in that a step is provided in the thickness direction of the analytical device at the boundary between the region A and the region B on the surface of the analytical device, and the step satisfies either the following requirement (i) or (ii). (i) The area A is lower than the area B. (ii) The region A is higher than the region B, and the region A is covered with a restricting member that is impermeable to the sample. [Configuration 2] The analytical device according to configuration 1, wherein the step satisfies the requirement (i), and the region A is a region where the regulating member is not present and is formed in a doughnut shape. [Configuration 3] An analytical device according to configuration 1, wherein the step satisfies the requirement (i) and the region A is formed by discontinuously providing regions where the regulating member is not present. [Configuration 4] 2. The analytical device according to configuration 1, wherein the step satisfies the requirement (ii) and the region A is formed in a doughnut shape. [Method 1] A testing method using the analytical device according to any one of configurations 1 to 4, A method for testing a sample, characterized in that the boundary between the region A and the region B is included in the range in which the sample spreads when the sample is dispensed. [Explanation of symbols]

[0068] 1. Flow chamber (flow chamber 1) including reference electrode 7 2. Flow path chamber (flow path chamber 2) including working electrode 8 3: Flow channel connecting flow channel chamber 1 and flow channel chamber 2 5. Channel wall 6. Dispensing section 7...Reference electrode 8...Working electrode 9. Ion-selective membrane Ionic crystals containing 10···Cl ions 11. Regulating member 12 Regulating member cutout 13. Regulating member cutout 14. Regulating member 15. Regulating member S... Specimen X···Exposed surface of ion-selective membrane 9

Claims

1. An analytical device having a hydrophilic or porous flow path region surrounded by hydrophobic flow path walls disposed in or on a substrate, The surface of the analytical device is a dispensing unit into which the sample is dispensed; an area B that is adjacent to the periphery of the dispensing section and is provided so as to surround the dispensing section, and is covered with a restricting member that is impermeable to the sample; an area A formed adjacent to the area B on a side not facing the dispensing portion; is established, An analytical device characterized in that a step is provided in the thickness direction of the analytical device at the boundary between the region A and the region B on the surface of the analytical device, and the step satisfies either the following requirement (i) or (ii). (i) The area A is lower than the area B. (ii) The region A is higher than the region B, and the region A is covered with a restricting member that is impermeable to the sample.

2. 2. The analytical device according to claim 1, wherein the step satisfies the requirement (i), and the region A is a region where the regulating member is not present and is formed in a doughnut shape.

3. The analytical device according to claim 1 , wherein the step satisfies the requirement (i), and the region A is formed by discontinuously providing regions where the regulating member is not present.

4. The analytical device according to claim 1 , wherein the step satisfies the requirement (ii) and the region A is formed in a doughnut shape.

5. A testing method using the analytical device according to any one of claims 1 to 4, A method for testing a sample, characterized in that the boundary between the region A and the region B is included in the range in which the sample spreads when the sample is dispensed.

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