Reaction plate

Abstract

Provided is a reaction plate included in a biochemical reaction substrate used for allergy test or the like, whereby 1) a stable test can be performed by performing sufficient cleaning even when the number of times a reaction area is cleaned is reduced, and / or 2) the same test can be performed in an outer peripheral section and a central section of the reaction area by matching the detection sensitivity of the outer peripheral section and the detection sensitivity of an inner peripheral section of the reaction area. The reaction plate included in a biochemical reaction substrate has: a reaction area in which a specific binding substance that specifically reacts with a test substance in a specimen is immobilized; and an outflow prevention wall formed so as to surround the reaction area. A part where the reaction area and the outflow prevention wall abut is larger than a corner R of 0.10 mm.

Description

Reaction Plate

[0001] The present invention relates to a reaction plate to be incorporated into a biochemical reaction substrate for measuring the amount of a sample substance having physiological activity based on a biochemical reaction process such as an immunoassay.

[0002] Testing for biological substances, which checks the presence and amount of substances in the body, is important for understanding health conditions and determining treatment methods. Furthermore, in today's increasingly diverse living environments, there is a need to perform a wide variety of tests for biological substances, and there is a demand for faster and more sensitive testing. For example, when treating allergic diseases, it is important to first understand the allergic disease that one is suffering from. In recent years, there have been a wide variety of causes of allergies, and identifying the cause is necessary to receive appropriate treatment, such as using appropriate medications.

[0003] Various methods for testing allergies are known, including, for example, a method described in Patent Document 1 in which IgE antibodies against specific allergens in a blood sample collected from a subject are quantified by solid-phase sandwich immunoassay. In this method, a solid-phase support such as a glass filter is prepared by adsorbing a ligand-capturing antibody and blocking protein adsorption sites other than the ligand-capturing antibody adsorption site with a blocking agent such as casein. A specific allergen, such as a dust mite or pollen, is bound to the ligand, and this is mixed with a blood sample to form a complex between the specific allergen bound to the ligand and the IgE antibody against the specific allergen in the blood sample. A mixture containing this complex is then added to the solid-phase support on which the ligand-capturing antibody is adsorbed, allowing the ligand portion in the complex to bind to the ligand-capturing antibody. Next, an anti-IgE antibody labeled with an enzyme or the like is added, allowing the IgE antibody portion in the complex to bind to the labeled anti-IgE antibody. Next, excess labeled anti-IgE antibody that has not bound to the complex is removed, and a color reaction according to the type of label is carried out to detect the labeled anti-IgE antibody that has bound to the IgE antibody. The detection results obtained are compared with a calibration curve prepared in advance using labeled IgE antibody, and the IgE antibody against the specific allergen in the blood sample is quantified.

[0004] To perform the above test, a method and device for testing for the presence or absence of allergies is known, using a biological reaction substrate in which a specific allergen is bound to a porous filter of the biological reaction substrate. Another example of a method and device for testing for the presence or absence of allergies using a biological reaction substrate is a biochemical reaction substrate as described in Patent Document 2. The substrate includes a reaction plate, an absorbent, a storage container having a reaction plate storage section for storing the reaction plate, an absorbent storage section for storing the absorbent, and an insulated section, and a cover attached to the storage container so as to cover at least a portion of the reaction plate and absorbent stored in the storage container. The reaction plate has a reaction area in which a specific binding substance that specifically reacts with a test substance in a sample is immobilized, and a flow path section connecting the absorbent and the reaction area. The cover has an injection hole for injecting a sample or the like into the reaction plate.

[0005] JP 2011-133285 A International Publication No. WO2019 / 151468

[0006] For example, the test using the reaction plate described in Patent Document 2 has a reaction area in which a specific binding substance (e.g., an antigen (allergen)) that reacts specifically with the test substance in the sample is immobilized, and a flow path section that connects the absorber and the reaction area, and the cover has an injection hole for injecting the sample, etc. into the reaction plate, so the number of test steps can be reduced (e.g., the step of absorbing cleaning liquid from the reaction area in order to drain the cleaning liquid can be reduced), making it easier to perform the test.

[0007] Using such a reaction plate, testing is carried out in an analytical device through the following processes: (1) a diluted sample adding step in which a sample (which may be diluted and will hereinafter also be referred to as a "diluted sample") is dispensed into a reaction area of ​​the reaction plate of the biochemical reaction substrate and allowed to bind to IgE immobilized in the reaction area; (2) a sample washing step in which washing is performed with a washing solution to remove unreacted sample components in the reaction area; (3) a labeled antibody adding step in which an anti-IgE antibody (a so-called labeled secondary antibody, hereinafter also referred to simply as a "labeled antibody" in this specification) labeled with an enzyme such as ALP (alkaline phosphatase) is added to allow binding of the IgE antibody to the labeled antibody; (4) a labeled antibody washing step in which washing is performed with a washing solution to remove unreacted labeled antibody; and (5) an inspection step in which a chemiluminescent substrate is added and the chemiluminescence intensity is photographed with a camera. In particular, in the (4) labeled antibody washing step, washing is performed multiple times (for example, about 10 times) to wash the labeled antibody, and the more times this labeled antibody washing step is performed, the longer the washing step time becomes, which poses a problem that it is not possible to shorten the test time. Note that the "(4) labeled antibody washing step" refers to a series of steps that start from a state in which the labeled antibody added in step (3) has been removed (discharged) from the reaction area, and that include injecting a washing solution into the reaction area, stirring the washing solution, and removing (discharged) the washing solution, and the "number of labeled antibody washing steps" refers to the number of times this series of steps has been performed.

[0008] Therefore, the inventors reviewed the number of times the labeled antibody was washed and confirmed whether a fewer number of washes than the previous method would affect the test results. As a result of this confirmation, as shown in Figure 10(b), unnecessary luminescence was confirmed in the reaction area around the outflow prevention wall that separates the reaction area. It was found that this was due to the presence of labeled antibody that had not been completely washed away remaining in the reaction area around the outflow prevention wall, causing the luminescence of the labeled antibody that had not been completely washed away. It was also found that the presence of such unnecessary luminescence could lead to problems such as inaccurate testing or the need to increase the number of wash steps.

[0009] Furthermore, the reaction area of ​​the reaction plate described in Patent Document 2 is coated in advance with an immobilizing agent such as a polymer, and a specific binding substance (e.g., an antigen (allergen)) that specifically reacts with a test substance in a specimen is immobilized to the reaction area via the immobilizing agent. However, it has been found that if the immobilizing agent is not coated to a uniform thickness over the entire surface of the reaction area, the amount and density of the specific binding substance immobilized in the reaction area will vary depending on the immobilization site, resulting in a problem in that even the same specific binding substance will produce different test results depending on the site.

[0010] For example, the reaction area in the reaction plate described in Patent Document 2 is surrounded by a spill prevention wall at its outer edge. Therefore, when the reaction plate is coated with an immobilizing agent, the immobilizing agent is attracted by the surface tension of the inner wall of the spill prevention wall, resulting in a thicker coating film of the immobilizing agent in the reaction area around the spill prevention wall. This can result in a thicker coating film in the reaction area around the spill prevention wall than in the center of the reaction area. This can lead to problems such as different detection sensitivity between the center of the reaction area and the outer periphery around the spill prevention wall, resulting in different test results. Therefore, to perform stable testing, it is possible to use only the center of the reaction area. However, this increases the area of ​​the reaction area, which increases the amount of sample (sample dilution solution), antibody, washing solution, etc. used, resulting in a longer washing process time and making it difficult to shorten the test time.

[0011] Therefore, the present invention has been made to solve such problems, and aims to: 1) provide a reaction plate that allows stable testing by ensuring reliable cleaning even when the number of times the reaction area is cleaned is reduced, and / or 2) provide a reaction plate that allows similar testing to be performed in the outer periphery and the center by matching the detection sensitivity between the outer periphery and the center of the reaction area.

[0012] The reaction plate according to the present invention, which solves the above-mentioned problems, is a reaction plate to be incorporated into a biochemical reaction substrate, and is characterized in that it has a reaction area in which a specific binding substance that reacts specifically with a test substance in a specimen is immobilized, and an outflow prevention wall formed so as to surround the reaction area, and the portion where the reaction area and the outflow prevention wall abut against each other forms a corner R, and the corner R is greater than 0.10 mm.

[0013] In the reaction plate according to the present invention, it is preferable that the corner R is greater than 0.12 mm.

[0014] In the reaction plate according to the present invention, it is preferable that the angle formed between the outflow prevention wall and the reaction area is 91 degrees or more.

[0015] In the reaction plate according to the present invention, it is preferable that the angle formed between the outflow prevention wall and the reaction area is 95 degrees to 130 degrees.

[0016] Furthermore, it is preferable that the reaction plate according to the present invention has a flow path section that is connected to the reaction area, prevents the specimens, etc. from flowing out when the specimens, etc. in the reaction area are stirred, and is capable of discharging the specimens, etc. after stirring.

[0017] In the reaction plate according to the present invention, it is preferable that the flow path portion has a slope formed so as to rise from the reaction area.

[0018] Furthermore, in the reaction plate according to the present invention, it is preferable that the flow path portion is formed from the reaction area to an end of the reaction plate, and that the width of the flow path of the flow path portion at the end is narrower than the width of the reaction area.

[0019] In the reaction plate according to the present invention, it is preferable that the flow path portion includes a flow path wall that is continuous with the outflow prevention wall, and the flow path wall is formed in a streamlined shape along the flow path of the flow path portion.

[0020] In addition, in the reaction plate according to the present invention, it is preferable that the outflow prevention wall has an opening that opens toward any end of the reaction plate, and the flow path portion is formed between the opening and the end.

[0021] In addition, in the reaction plate according to the present invention, it is preferable that the flow path wall of the flow path portion is curved in a streamlined shape along the flow path so that the width of the flow path narrows from the reaction area toward the end, and is formed so that the width of the flow path widens on the end side.

[0022] In the reaction plate according to the present invention, it is preferable that the surface of the reaction area has a coating film that fixes the specific binding substance to the reaction area.

[0023] Furthermore, the method for manufacturing a reaction plate according to the present invention is a method for manufacturing a reaction plate to be incorporated into a biochemical reaction substrate, the method comprising: a reaction area in which a specific binding substance that reacts specifically with a test substance in a specimen is immobilized; and an outflow prevention wall formed to surround the reaction area, the portion where the reaction area and the outflow prevention wall abut each other forming a corner R, the corner R being greater than 0.10 mm; and a method for manufacturing a reaction plate to be incorporated into a biochemical reaction substrate, the method comprising: rotating the reaction plate to coat the reaction area with an immobilizing agent for immobilizing the specific binding substance that reacts specifically with the test substance in the specimen in the reaction area.

[0024] According to the present invention, the reaction plate has a predetermined corner radius where the reaction area and the outflow prevention wall abut, so that even if the number of washes during the washing process is reduced, reliable washing can be performed, reducing the amount of liquid remaining in the reaction area around the outflow prevention wall, thereby improving test accuracy. Furthermore, according to the present invention, the reaction plate has a coating film with a uniform thickness that fixes the specific binding substance to the reaction area, so that detection sensitivity is consistent between the outer periphery and the center of the reaction area, improving test accuracy. Furthermore, according to the present invention, the flow path of the flow path section that communicates with the reaction area is preferably streamlined, so that cleaning during the washing process is more reliable and test accuracy is improved. Furthermore, because the end of the flow path is formed to expand outward, it is possible to prevent liquid from leaking from the flow path section even if the liquid absorption performance of the absorbent body decreases.

[0025] 5 is a perspective view of an analytical device that performs a test using a reaction plate according to an embodiment of the present invention. FIG. 6 is a perspective view of a biochemical reaction substrate into which a reaction plate according to an embodiment of the present invention is incorporated. FIG. 7 is an exploded view of a biochemical reaction substrate into which a reaction plate according to an embodiment of the present invention is incorporated. FIG. 8 is a perspective view of a reaction plate according to an embodiment of the present invention. FIG. 9 is a cross-sectional view taken along line A-A in FIG. 4. FIG. 10 is an enlarged view of part B in FIG. 11. FIG. 12 is a perspective view of a modified example of a reaction plate according to an embodiment of the present invention. FIG. 13 is a plan view of a modified example of a reaction plate according to an embodiment of the present invention. FIG. 14 is a top view for explaining the arrangement of antigens (allergens) in the reaction area of ​​a reaction plate. Illustrative detection results of a test, where (a) is a view explaining the detection results of a test using a reaction plate according to an embodiment of the present invention, and (b) is a view explaining the detection results of a conventional reaction plate.

[0026] The reaction plate according to the present invention will be described below with reference to the drawings. Note that the following embodiments do not limit the invention according to each claim, and not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0027] 7 is a perspective view showing a modified example of a reaction plate according to an embodiment of the present invention; FIG. 8 is a plan view showing a modified example of a reaction plate according to an embodiment of the present invention; FIG. 9 is a top view for explaining the arrangement of antigens (allergens) in the reaction area of ​​a reaction plate; and FIG. 10 is a diagram for explaining the detection results of a test, where (a) is a diagram for explaining the detection results of a test using a reaction plate according to an embodiment of the present invention, and (b) is a diagram for explaining the detection results of a conventional reaction plate.

[0028] 1, a reaction plate 10 according to this embodiment is incorporated into a biochemical reaction substrate 5 and is inserted into an input section 3 of an analyzer 1 together with a reagent cartridge 6 containing a specimen and a cleaning solution for testing. The analyzer 1 comprises a housing 4 having an operation panel 2 and the input section 3 in which the reagent cartridge 6 and the biochemical reaction substrate 5 are mounted. The input section 3 can be opened and closed by an attached door (not shown).

[0029] The interior of the analyzer 1 is divided into an installation area, a barcode reading area, a dispensing area, a mixing area, a detection area, and a drainage area. Arranging each area on the same straight line increases area efficiency, allowing the analyzer 1 to be made more compact. A guide means (e.g., a moving table) for guiding the biochemical reaction substrate 5 from the installation area to the drainage area may also be attached. For example, the mixing area and the dispensing area may overlap, and adjacent areas may overlap.

[0030] As shown in FIG. 2 , the reaction plate 10 according to this embodiment can be incorporated into a biochemical reaction substrate 5 for use. The biochemical reaction substrate 5 need only be capable of housing the reaction plate 10 according to this embodiment therein, and may further include a cover 30 and / or a storage container 40. The cover 30 has a substantially circular injection hole 31 formed therein, and is configured so that when the reaction plate 10 according to this embodiment is housed therein, the injection hole 31 is positioned corresponding to the reaction area 11 of the reaction plate 10. The bottom of the storage container 40 may be formed with a concave heat-insulating portion 43, which can be configured so that a heater of an analytical device (described later) can contact the bottom to heat the reaction area 11. The cover 30 may also have an uneven anti-slip means 35 formed on its outer peripheral sidewall, which can be configured to allow an examiner to securely grip the biochemical reaction substrate 5.

[0031] 3, the storage container 40 is formed with a reaction plate storage section 41 for storing the reaction plate 10 according to this embodiment, and may further be provided with an absorber storage section 42 for storing the absorber 20 made of a porous material such as a sponge that can sufficiently absorb liquid. Note that, when the reaction plate 10 according to this embodiment and the absorber 20 are stored in the storage container 40, the tip of the flow path section 12 formed in the reaction plate 10 according to this embodiment is arranged to abut against the absorber 20.

[0032] As shown in FIG. 4 , the reaction plate 10 according to this embodiment may be any shape that can be fitted into a reaction plate storage section 41 formed in a storage container 40 without any problems, and may have, for example, a plate-shaped base section 14 that can be fitted into the reaction plate storage section 41. Furthermore, the reaction plate 10 includes an outflow prevention wall 13, which may be erected from the base section 14. The outflow prevention wall 13 may be, for example, a roughly annular wall, and the interior of the outflow prevention wall 13 defines a reaction area 11. Furthermore, the reaction plate 10 includes a flow path that communicates with the reaction area 11, and the flow path includes a slope 15 and constitutes at least a part of the flow path section 12. The outflow prevention wall 13 may have any shape that does not stagnate during drainage, and may be formed, for example, in a circular or elliptical shape. The reaction area 11 inside the outflow prevention wall 13 may also be formed in a circular or elliptical shape.

[0033] As shown in FIGS. 3 to 5 , a slope 15 that constitutes a flow path is provided at a position facing the absorbent 20 from the reaction area 11. The flow path is defined by a pair of flow path walls 12X and 12Y extending from the outer periphery of the outflow prevention wall 13. The pair of flow path walls 12X and 12Y are preferably curved in a streamlined shape along the flow path so that the width of the flow path (including the slope 15) (i.e., the distance between the pair of flow path walls 12X and 12Y) continuously changes. For example, as shown in FIGS. 4 and 5 , the distance between the pair of flow path walls 12X and 12Y gradually narrows and then gradually widens from the reaction area 11 toward the end side 15′ of the slope 15. The pair of flow path walls 12X and 12Y define a flow path (including the slope 15) for draining the sample or the like dispensed into the reaction area 11. The drained liquid discharged through the flow path is absorbed by the absorbent 20. In other words, the pair of flow path walls 12X and 12Y have slopes 15 formed to rise up from the reaction area 11 so that by tilting the biochemical reaction substrate 5, specimens and the like can be discharged from the reaction area 11 through the flow path toward the absorbent 20 without waste.

[0034] The flow path walls 12X and 12Y are preferably formed continuously with the outflow prevention wall 13 and configured in a curved shape from the outflow prevention wall 13 to the flow path walls 12X and 12Y, preferably without any sharp corners. If there is a visible "seam" at the joining point between the inner wall portions of the flow path walls 12X and 12Y and the inner wall portion of the outflow prevention wall 13, for example, if there is an uneven shape such as a sharp protruding shape, a concave shape, or a recessed shape, or if there is a stepped shape, the liquid being discharged is likely to remain at the seam, and the liquid, etc., is likely to remain at the seam without being completely discharged. As a result, this increases the number of cleaning steps required during inspection. Therefore, it is preferable that the portion connecting the outflow prevention wall 13 to the flow path walls 12X and 12Y be curved in a streamlined shape, and it is preferable that there is no visible seam.

[0035] Furthermore, even if the heights of the top surfaces of the two walls are different (there is a gap) at the locations where the flow path walls 12X and 12Y contact the outflow prevention wall 13, samples and the like are likely to remain in the gap and not be able to be completely discharged, so it is preferable that the top surface be formed continuously and without gaps so that no gaps occur.

[0036] The inclined surface 15 constituting the flow path is preferably formed at an angle of about 5° to 70° from the base portion 14 (or the reaction area 11), with the angle of the inclination being more preferably 12° to 50°, even more preferably 17° to 35°, and the most preferable angle being 23°. The greater the angle of the inclination of the inclined surface 15, the more effectively it can prevent leakage of the solution dispensed into the reaction area 11, but on the other hand, it becomes more likely that the solution will be difficult to drain.

[0037] In this way, the flow path section 12 includes a flow path formed from the reaction area 11 to the end side 15′, and the length of the end side 15′ of the flow path constituted by the flow path section 12 in the width direction (the short side direction of the base section 14, i.e., the distance between the flow path walls 12X and 12Y) is formed to be narrower than the length of the longest point in the reaction area 11, and the end side 15′ of the flow path constituted by the flow path section 12 is formed so that, in side view, the inclined surface 15 abuts at an acute angle against the upper surface of the absorber 20 (the angle formed by the upper surface of the absorber 20 and the extension surface of the inclined surface 15 is an acute angle).

[0038] As shown in Figures 5 and 6, the side surface (inner surface) of the outflow prevention wall 13 facing the reaction area 11 is preferably inclined outward relative to the vertical direction from the base portion 14 on which the reaction area 11 is formed. The angle θ between the inner surface of the outflow prevention wall 13 and the surface of the reaction area 11 is preferably 91° or more when viewed from the reaction area 11 side. If the angle is 91° to 135°, the sample or the like dispensed into the reaction area 11 can be prevented from leaking out of the reaction area 11 during agitation. More preferably, the angle θ is 95° to 130°, and even more preferably, 95° to 125°, 95° to 120°, 97° to 115°, or 97° to 113°. By making the angle θ greater than 90°, binding of the sample or the like in the reaction area 11 during agitation and washing of unreacted sample or the like with a washing solution can be performed without leaving any residual liquid. On the other hand, if the angle θ is too large, stirring may cause the specimen or the like to overflow the outflow prevention wall 13 and flow out of the reaction area 11. Therefore, by setting a preferable angle θ, it is possible to achieve the object of the present invention.

[0039] In addition, the shape of the vertical cross section of the base portion 14 at the portion where the inner surface of the outflow prevention wall 13 abuts against the reaction area 11, i.e., the continuous portion between the outflow prevention wall 13 erected from the base portion 14 and the base portion 14 on the reaction area 11 side, forms a corner R.

[0040] By forming this corner R, it is possible to prevent the specimen or the like dispensed into the reaction area 11 from remaining at the periphery of the reaction area 11 (around the outflow prevention wall 13 in the reaction area) when it is attempted to be drained, and for example, it is possible to prevent the labeled antibody that is attempted to be drained from remaining at the periphery of the reaction area 11. As a result, it is possible to improve the accuracy of the test.

[0041] The corner R (the radius of the corner R) is preferably greater than 0.10 mm, more preferably greater than 0.12 mm, and even more preferably 0.25 mm or greater. The corner R may be 0.75 to 0.11 mm, 0.60 to 0.12 mm, 0.50 to 0.12 mm, 0.40 to 0.20 mm, or 0.35 to 0.25 mm. By making the corner R greater than 0.10 mm, binding of specimens and the like in the reaction area 11 during stirring and washing of unreacted specimens and the like with a washing solution can be performed without leaving any residual liquid. On the other hand, if the corner R is too large, stirring may cause specimens and the like to overflow the outflow prevention wall 13 and flow out of the reaction area 11.

[0042] As described above, the reaction plate 10 according to this embodiment has the outflow prevention wall 13 formed so as to surround the reaction area 11, and a predetermined corner R is formed at the contact point between the inner surface of the outflow prevention wall 13 and the reaction area 11. By forming the corner R in this manner, it is possible to prevent the sample from flowing out of the reaction area 11 even when the biochemical reaction substrate 5 is stirred in the analyzer 1, and to reduce the amount of excess liquid remaining in the reaction area 11 after the sample is drained after stirring, with fewer washings.

[0043] Furthermore, it is preferable that an immobilizing agent for immobilizing the specific binding substance is coated on the surface of the reaction area 11. For example, a polymer (copolymer) can be used as the immobilizing agent, and there is no particular limitation as long as it can immobilize the specific binding substance. For example, a conventionally known polymer containing multiple photoreactive groups can be used.

[0044] A method for coating the surface of the reaction area 11 with the immobilizing agent can be used (sometimes referred to as spin coating), in which an amount of immobilizing agent sufficient to coat the reaction area 11 is poured into any location within the reaction area 11 of a reaction plate 10 comprising a reaction area 11 not coated with an immobilizing agent and an outflow prevention wall 13 (preferably, a flow path section 12), and then the reaction plate 10 is rotated. When coating by rotation, not only the surface of the reaction area 11 but also the inner wall surfaces of the outflow prevention wall and the flow path wall can be coated with the immobilizing agent. As a result, the effect of smoothing the flow of liquid when discharging a cleaning solution or the like in a washing step can be obtained.

[0045] Furthermore, the reaction plate 10 of the present invention has rounded corners at the contact points between the reaction area 11 and the outflow prevention wall 13, which allows the thickness of the coating layer of the immobilizing agent to be more consistent than when there are no rounded corners. Without the rounded corners, the immobilizing agent coated during rotation may bounce off the outflow prevention wall 13; as a result, the thickness of the coating layer at the outer periphery of the reaction area 11 (near the outflow prevention wall 13) may be thicker than the thickness of the coating layer at the center of the reaction area.

[0046] The rotation speed for coating the fixing agent may be any speed that results in a uniform thickness of the coating layer after coating, and any speed can be appropriately selected. The rotation speed may be constant or may be gradually increased. When the speed is gradually increased, three or more speed stages may be set. The rotation conditions for producing the fixing agent coating layer are preferably divided into two stages, with the first stage being a low speed and the second stage being a high speed.

[0047] Furthermore, if necessary, a blocking agent may be applied in advance to the entire surface of the reaction area 11. The blocking agent can suppress non-specific adsorption in the reaction area 11. As the blocking agent, a synthetic polymer not derived from animals or plants, such as polyethylene glycol, can be used using common techniques, and can be appropriately selected and used depending on the material of the reaction plate 10, the properties of the target substance such as an antigen, the specimen such as blood, and the reagent such as the washing solution.

[0048] Furthermore, when the inside of the outflow prevention wall 13 is defined as the reaction area 11, coating the inner wall surfaces of the reaction area 11 and the outflow prevention wall 13 with a blocking agent can make the affinity (e.g., hydrophilic, hydrophobic, or water-repellent) of the inside of the outflow prevention wall 13 and the reaction area 11 with liquids such as specimens the same, which has the secondary effect of making it easier to discharge the specimens.

[0049] The reaction plate according to this embodiment may include components other than the reaction area 11, the flow path section 12, the outflow prevention wall 13, the base 14, and the inclined surface 15. For example, as shown in Figures 7 and 8, the reaction plate 10' may be formed so that the end side of the flow path section 12 is spaced apart so as to further expand in diameter outward.

[0050] The reaction plate 10' may also have a pair of protrusions 16 extending from the base 14 near the positions where the flow path walls 12X and 12Y of the flow path section 12 connect to the outflow prevention wall 13. Furthermore, the tip of the flow path section 12 may be formed to have an upper surface 17 that is substantially parallel to the upper surface of the protrusions 16. Such protrusions 16 and upper surface 17 facilitate handling of the reaction plate 10'. For example, when coating the reaction areas 11 with an immobilizing agent or immobilizing a specific binding substance in the reaction areas 11, the reaction plate 10' can be handled by gripping the protrusions 16 with a tool or machine. Furthermore, when storing multiple reaction plates 10', even if they are stacked on top of each other, the protrusions 16 and upper surface 17 abut against the back surface of the base 14, allowing for stable storage.

[0051] Furthermore, it is preferable to position the protruding portion 16 of the reaction plate 10' at a position where it does not come into contact with the inner walls of the flow path walls 12X and 12Y and / or the outflow prevention wall 13. If the protruding portion 16 comes into contact with the inner walls of the flow path section 12 and / or the outflow prevention wall 13, the protruding portion 16 will protrude into the inner wall, which may result in liquid remaining in the protruding portion when the specimen or the like is discharged, thereby increasing the number of discharge steps.

[0052] A specific binding substance (e.g., an antigen) is immobilized on the reaction area 11 of the reaction plate 10 according to this embodiment. Only one type of specific binding substance may be immobilized, but preferably multiple types are immobilized. This is because multiple types of substances can be detected in a single test. Furthermore, one type of specific binding substance may be immobilized not only in one location but also in multiple locations. This is because the detection accuracy for one type of substance can be improved.

[0053] For example, in the reaction plate 10 of FIG. 9 , 25 types of antigens 50 are arranged and immobilized in the reaction area 11; and each type of antigen 50 is immobilized in three locations (three spots). That is, in the reaction plate of FIG. 9 , a plurality of sets 51 (e.g., 3 spots / set) of antigens 50 are arranged in a predetermined number of sets 51 (e.g., 75 spots / 25 sets). By arranging the antigens in this manner, the number of antigens 50 placed in the reaction area 11 (the so-called n number) can be increased by the number of spots (e.g., n = 3), and the area within the reaction area 11 can be effectively utilized (wasted space can be eliminated). Furthermore, by arranging the antigens in the form of sets 51 as described above, it is possible to easily distinguish them from other antigens, thereby preventing contamination of the reaction results with other antigens in the test.

[0054] Next, the operation of the analyzer 1 for performing allergy testing using the biochemical reaction substrate 5 incorporating the reaction plate 10 according to this embodiment will be described. As shown in Fig. 1, the biochemical reaction substrate 5 and the reagent cartridge 6 are set in the input unit 3. The reagent cartridge 6 is a member that contains a specimen (including a diluted specimen) and reagents.

[0055] Thereafter, in the analyzer 1, the specimen and reagents in the reagent cartridge 6 are dispensed into the reaction area 11 of the biochemical reaction substrate 5. For example, the analyzer 1 is provided with a dispensing nozzle, and the reagent cartridge 6 is also provided with a tip, and the tip housed in the reagent cartridge 6 is fitted to the tip of the dispensing nozzle to aspirate the specimen, reagent, etc. in the reagent cartridge 6 from the reagent cartridge 6. The aspirated specimen, reagent, etc. can then be dispensed into the reaction area 11 through the injection hole 31 of the biochemical reaction substrate 5.

[0056] This dispensing is performed through a diluted specimen adding step in which the specimen is dispensed into a reaction area of ​​a reaction plate of a biochemical reaction substrate and allowed to bind to IgE immobilized in the reaction area; a specimen washing step in which unreacted specimen components in the reaction area are washed with a washing solution to remove them; a labeled antibody adding step in which a labeled antibody is added and the IgE antibody is allowed to bind to the labeled antibody; a labeled antibody washing step in which unreacted labeled antibody is washed with a washing solution to remove them; and a chemiluminescent substrate adding step in which a chemiluminescent substrate is added.

[0057] After use in dispensing, the tip is separated from the dispensing nozzle and returned to a predetermined position in the reagent cartridge 6. At this time, by returning the used tip to its original position, there is no need to provide a location for collecting used tips, which allows the size of the reagent cartridge to be reduced.

[0058] After dispensing, the movable table can be reciprocated in this state to agitate the specimen, reagent, and washing solution dispensed into the reaction area 11 of the biochemical reaction substrate 5 as needed during the reaction process. The direction of the reciprocating motion of the movable table is along the short side direction of the biochemical reaction substrate 5. By reciprocating in this direction, the possibility of the specimen or the like passing through the flow path 12 due to agitation is eliminated, and drainage to the absorber 20 side is prevented.

[0059] When stirring is completed, the movable table is transported to the drainage section to drain the specimen and the like dispensed into the reaction area 11. In this drainage step, the substrate holder of the movable table is tilted so that the biochemical reaction substrate 5 held on the substrate holder is tilted with the absorber 20 facing downward, and the specimen and the like dispensed in the reaction area 11 are drained into the absorber 20 through the flow path of the flow path section 12. Any configuration may be employed for the mechanism for tilting the substrate holder. For example, a stopper may be provided at the end of a guide member that guides the movable table, a tilting cam may be provided on the substrate holder, and the movable table may be moved to a position where the tilting cam abuts against the stopper, causing the tilting cam to rise. Since the substrate holder is connected to the movable table via its rotation axis, the substrate holder is tilted around the rotation axis in accordance with the operation of the tilting cam.

[0060] After the specimen and other liquids have been drained, the reaction area 11 of the biochemical reaction substrate 5 is moved to the detection camera. The detection camera is then lowered, and the light-shielding member attached to its tip is brought into close contact with the biochemical reaction substrate 5, blocking external light from entering the biochemical reaction substrate 5 and the testing device. In this state, the presence or absence of luminescence from the labeled antibody can be detected, thereby detecting the presence or absence of an allergic reaction. The luminescence of the labeled antibody is caused by the luminescent substrate that is luminescent by the labeled anti-IgE antibody, which is dispensed in the dispensing step. This luminescence substrate is allowed to react in the reaction area 11 under specified environmental conditions for a specified time, and the intensity of the luminescence obtained as a result of this reaction is measured by the detection camera.

[0061] 10(a) is a photograph showing the test results when the reaction plate 10 according to the present embodiment was used and the number of washes was set to three, which is half or less than the number of washes conventionally performed. Also, FIG. 10(b) is a photograph showing the test results when a conventional reaction plate was used and the number of washes was set to three, which is also half or less than the number of washes conventionally performed. Each wash (each wash) may be performed to the extent that the sample or other object to be washed is sufficiently mixed with the washing solution, and the time and stirring method may be set appropriately.

[0062] As is clear from Figure 10(b), when a conventional reaction plate was used and the number of washings was reduced to half or less of the conventional number, unintended luminescence was observed at the outer edge of the reaction area 11 (near the outflow prevention wall 13). Therefore, luminescence due to the labeled anti-IgE antibody could not be clearly observed at the outer edge of the reaction area 11. This is because the solution containing the labeled antibody that should have been washed remained, indicating insufficient washing. Although the results are not shown, to perform sufficient washing using a conventional reaction plate, washing was required seven or more times.

[0063] In contrast, as is clear from Figure 10(a), in the reaction plate 10 according to this embodiment, no unintended luminescence is observed at the outer edge of the reaction area 11, indicating that no liquid remains. Therefore, a clear luminescence state based on the labeled anti-IgE antibody can be confirmed. Note that the above-mentioned "sufficient washing" refers to a level where, when the luminescence of the labeled antibody is detected with a detection camera, there is no noise due to unreacted residual labeled anti-IgE antibody, or where the detection does not pose a problem.

[0064] As described above, in an allergy test using the reaction plate 10 according to this embodiment, it is possible to increase the sensitivity of the test, reduce the test time and labor required, and perform the test efficiently.

[0065] Next, the effects of the "corner R at the point where the reaction area 11 and the outflow prevention wall 13 meet" and the "angle θ between the reaction area 11 and the outflow prevention wall 13" of the reaction plate 10 according to this embodiment will be explained with reference to examples.

[0066] For the reaction plates 10 of each example and comparative example, the corner R of the example was set to about 0.3 mm, the angle θ of Example 1 was set to 100°, the angle θ of Example 2 was set to 110°, and the angle θ of Example 3 was set to 120°; the corner R of the comparative example was set to 0.1 mm, and the angle θ of Example 3 was set to 100°.

[0067] As described above, a plurality of sets 51 (e.g., 3 spots / set) of antigens 50 are arranged in a predetermined number of sets 51 (e.g., 75 spots / 25 sets) in the reaction area 11 of the reaction plate 10 in each of the examples and comparative examples. When the antigens 50 contained in each set 51 bind to a sample and emit light from the labeled antibody, the extent to which the intensity of the light emission varies within the reaction area 11 was confirmed. The light emission intensity was confirmed by measuring the intensity of the light emission resulting from the reaction using a detection camera after the above-described dispensing step and reaction step, with the reaction area shielded from light.

[0068] The average luminescence intensity of the "periphery" was calculated by setting the average luminescence intensity of the "center" when using the reaction plates of each Example and Comparative Example as 100. The "periphery" in the Examples and Comparative Examples was defined as the area located within 1.2 mm from the outflow prevention wall 13, and the "center" was defined as the remaining area.

[0069] The central and peripheral parts of the reaction area 11 are defined as follows: the peripheral part is defined as the part located within 1.2 mm from the outflow prevention wall 13, and the central part is defined as the remaining part.

[0070] The "center" of the reaction area 11 refers to the region within a given distance (for example, the radius (including the minor and major axes)) from the center point of the reaction area 11 when the reaction area 11 is substantially circular (including circular and elliptical shapes), and the "periphery" of the reaction area 11 refers to the region outside the center. In the case where the corner R of the present invention is 0.1 mm or less and the formed angle is 100°, the peripheral region may be the portion where the luminescence intensity is 75 or less, 71 or less, 70 or less, 65 or less, or 60 or less, when the average luminescence intensity of the center is 100. The specific binding substance immobilized on the boundary between the peripheral region and the center is defined as the peripheral region.

[0071] In the reaction plates of the Examples and Comparative Examples, antigens were used as specific binding substances, and the antigens were arranged in three spots per set. However, specific binding substances immobilized on the boundary between the outer periphery and the center were considered to be located in the outer periphery, and if even one of the three spots in one set was located in the outer periphery, the three spots per set were considered to be located in the outer periphery for evaluation.

[0072] As shown in Table 1 above, the average ratio of the emission intensity of the outer periphery to the emission intensity of the center was 86% for Example 1, 97% for Example 2, and 92% for Example 3. In contrast, the ratio for the comparative example was 71%, which revealed that the emission intensity of the outer periphery was about 30% lower than that of the center. If the variation in emission intensity reaches 30%, it will affect the detection results when measuring the emission intensity with a detection camera, and therefore it will be understood that the detection results for the outer periphery cannot be used for effective inspection.

[0073] Furthermore, the luminescence intensities of three randomly selected sets of spots (spot A, spot B, and spot C) arranged at the same positions on the periphery of the reaction area of ​​the reaction plates of the Example and Comparative Example were compared. Spot A was closest to the center of the reaction area, and spot C was furthest from the center of the reaction area. In the set, if the luminescence intensity of spot A was taken as 100%, the luminescence intensities of spots B and C in the Comparative Example were 84% and 61%, respectively, whereas the luminescence intensities of spots B and C in Example 2 were 100% and 91%, respectively.

[0074] As described above, in Examples 1 to 3, it was confirmed that the luminescence intensity in the outer periphery was approximately equal to that in the center, and that the luminescence intensity in each spot arranged in the outer periphery was also constant. Therefore, the reaction area 11 up to the vicinity of the outflow prevention wall 13 can be effectively utilized as a reaction area, which allows for space saving in the reaction area 11 and makes it possible to reduce the size of the reaction plate 10. Furthermore, by making the reaction plate 10 the same size as conventional plates, it becomes possible to arrange more antibodies 50, and it is also possible to increase the number of allergens that can be tested with one sample.

[0075] In the above-described reaction plate 10 according to the present embodiment, the injection hole 31 and the reaction area 11 of the biochemical reaction substrate 5 are formed in a circular shape, but these shapes are not limited to a circle and may be formed in, for example, an elliptical shape. It is clear from the claims that such modified or improved embodiments are also included within the technical scope of the present invention.

[0076] Furthermore, the reaction plate 10 according to the present embodiment described above can be a transparent or colored plate, but using a black plate allows for more sensitive measurements. Furthermore, the blocking agent applied to the reaction plate 10 can be applied to the reaction area 11, including the inside of the outflow prevention wall 13, the slope 15, and the inside of the flow path section 12, thereby further suppressing nonspecific adsorption. As described above, it is clear from the claims that such modified or improved embodiments are also included within the technical scope of the present invention.

[0077] DESCRIPTION OF SYMBOLS 1 Analytical device, 2 Operation unit, 3 Input unit, 4 Housing, 5 Biochemical reaction substrate 6 Reagent cartridge, 10 Reaction plate, 11 Reaction area, 12 Flow path unit, 12X and 12Y Flow path wall, 13 Outflow prevention wall, 14 Base unit, 15 Slope, 15' End side, 16 Protrusion, 17 Upper surface, 20 Absorbent, 30 Cover, 31 Injection hole, 35 Anti-slip means, 40 Storage container, 41 Reaction plate storage unit, 42 Absorbent storage unit, 43 Heat-insulating unit, 46 Opening, 50 Antigen, 51 Set, θ Angle formed.

Claims

1. A reaction plate to be incorporated into a biochemical reaction substrate, comprising a reaction area in which a specific binding substance that reacts specifically with a test substance in a sample is immobilized, and an outflow prevention wall formed to surround the reaction area, wherein the area where the reaction area and the outflow prevention wall meet forms a corner R, and the corner R is greater than 0.10 mm.

2. The reaction plate according to claim 1, wherein the corner R is greater than 0.12 mm.

3. The reaction plate according to claim 1 or 2, wherein the angle formed between the outflow prevention wall and the reaction area is 91 degrees or more.

4. A reaction plate according to any one of claims 1 to 3, wherein the angle formed between the outflow prevention wall and the reaction area is 95 degrees to 125 degrees.

5. A reaction plate according to any one of claims 1 to 4, characterized in that it has a flow path section that is connected to the reaction area, prevents the specimens, etc. from flowing out when the specimens, etc. in the reaction area are stirred, and is capable of discharging the specimens, etc. after stirring.

6. A reaction plate according to claim 5, wherein the flow path portion has a slope formed so as to rise from the reaction area.

7. A reaction plate according to claim 5 or 6, characterized in that the flow path section is formed from the reaction area to the edge of the reaction plate, and the width of the flow path of the flow path section at the edge is narrower than the width of the reaction area.

8. A reaction plate according to any one of claims 5 to 7, wherein the flow path section has a flow path wall that is continuous with the outflow prevention wall, and the flow path wall is formed in a streamlined shape along the flow path of the flow path section.

9. A reaction plate according to any one of claims 5 to 8, wherein the outflow prevention wall has an opening that opens toward any edge of the reaction plate, and the flow path portion is formed between the opening and the edge.

10. A reaction plate according to any one of claims 5 to 9, characterized in that the flow path wall of the flow path section is curved in a streamlined shape along the flow path so that the width of the flow path narrows from the reaction area toward the end, and is formed so that the width of the flow path widens on the end side.

11. A reaction plate according to any one of claims 1 to 10, characterized in that the surface of the reaction area has a coating film that fixes the specific binding substance to the reaction area.

12. A method for manufacturing a reaction plate to be incorporated into a biochemical reaction substrate, the reaction plate having a reaction area in which a specific binding substance that reacts specifically with a test substance in a sample is immobilized, and an outflow prevention wall formed to surround the reaction area, the portion where the reaction area and the outflow prevention wall abut forming a corner R, the corner R being greater than 0.10 mm, characterized in that the reaction area is coated with an immobilizing agent for immobilizing the specific binding substance that reacts specifically with the test substance in the sample by rotating the reaction plate.

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