Device for detecting antibody in sample

Abstract

The utility model provides a device for detecting an antibody in a sample, relates to the technical field of immunodetection, and solves the technical problem that the detection result of the existing chromatography test strip is easily influenced for the sample with higher interference factors. The test strip comprises a bottom plate, a sample pad, a combination pad, an NC (nitrocellulose) membrane and an absorption pad, the sample pad, the combination pad, the NC membrane and the absorption pad are arranged on the bottom plate, the sample pad is arranged between the combination pad and the NC membrane, and an isolating membrane used for accurately controlling the chromatography direction of a sample is further arranged between the combination pad and the sample pad. The sample pad and the combination pad are separated by the isolating membrane, so that a sample and a marker are respectively subjected to chromatography, and a test value is not easy to be low due to over-high concentration of a substance to be tested in the sample; the amount of the sample liquid participating in the reaction can be fixed, so that the reagent performance is improved; and the experiment progress can be controlled.

Description

Technical Field

[0001] The utility model relates to the technical field of immunoassay, and particularly to a device for detecting antibodies in a sample. Background Art

[0002] In the field of chromatography, the structure of a traditional chromatographic test strip is composed of a sample pad, a conjugate pad, a nitrocellulose membrane (NC membrane), an absorbent pad, and a PVC bottom plate. During the sample test reaction, the liquid sample is added to the sample pad, and chromatography starts through capillary action in the sample pad and successively passes through the conjugate pad, the NC membrane, and reaches the absorbent pad.

[0003] In the existing solutions, such as Figure 1 the traditional chromatographic test strip shown and a double-sample-pad colloidal gold immunochromatographic test strip proposed in the patent with the publication number CN115308406A, when it comes to samples with high interference, when adopting this structure, since the liquid passes through the sample pad and the conjugate pad in sequence, the interfering substances will combine with the markers in the conjugate pad, resulting in the results being seriously affected.

[0004] In the existing solutions, after adding a fixed amount of the sample, a diluent needs to be added for rinsing, and it is impossible to accurately determine the amount of the sample that has completed chromatography during rinsing, resulting in the test results being seriously affected by the interfering substances and the sample addition amount in the sample.

[0005] In the existing solutions, after adding the sample, only the experimental time can be measured, and the experimental progress cannot be controlled. In the traditional structure, when using one-step sample addition and two-step sample addition, the analyte in the sample first binds to the fluorescent microspheres. When chromatographing to the T line, the interfering substances, free analytes, and marker-analytes compete for the antigens / antibodies on the membrane at the same time. As a result, the following consequences are likely to occur: the test value is too low due to HOOK caused by too high a concentration of the analyte to be measured; the test result is incorrect due to too high a concentration of the interfering substances. Summary of the Utility Model

[0006] The purpose of the utility model is to provide a device for detecting antibodies in a sample to solve the technical problem that the detection results of the existing chromatographic test strips are easily affected by samples with high interference factors.

[0007] The embodiments of the utility model are realized through the following technical solutions:

[0008] A device for detecting antibodies in a sample, comprising a bottom plate, a sample pad, a conjugate pad, an NC membrane, and an absorbent pad provided on the bottom plate. The sample pad is arranged between the conjugate pad and the NC membrane, and an isolation membrane for controlling the contact area between the conjugate pad and the sample pad is further provided between the conjugate pad and the sample pad.

[0009] Preferably, the area of the isolation membrane is smaller than the contact area between the binding pad and the sample pad.

[0010] Preferably, the sample pad is connected to the bottom plate, the NC membrane and the binding pad, and the binding pad and the NC membrane partially overlap in the vertical direction.

[0011] Preferably, the NC membrane is provided with a test line T and a quality control line C.

[0012] Preferably, the absorption pad is connected to the bottom plate and the NC membrane.

[0013] Preferably, the binding pad is provided with a marker for binding to the substance to be detected in the sample.

[0014] With this technical solution, when in use, first drop the sample onto the sample pad, and make the sample chromatograph through the sample pad, the NC membrane, and the absorption pad in sequence;

[0015] When the sample chromatographs to a specific position, add the rinsing solution to the binding pad, and the rinsing solution chromatographs through the binding pad, the NC membrane, and the absorption pad in sequence. This position includes but is not limited to random positions on the NC membrane such as the test line T, the quality control line C, the marking line, etc.; wait for 5 - 15 minutes for the reaction to complete the test.

[0016] In this structure, the substance to be detected (antigen / antibody) in the sample first binds to the antigen / antibody coated on the test line T, and the rinsing solution releases the marker in the binding pad, thereby realizing that the marker signal is positively correlated with the concentration of the substance to be detected in the sample, so as to achieve the purpose of quantification.

[0017] In the traditional structure, after the sample is added, the sample can only chromatograph through the sample pad, the binding pad, the NC membrane, and the absorption pad in sequence. In the patented structure, after the sample is added, it is designed to only pass through the sample pad, the NC membrane, and the absorption pad, and the isolation membrane protects the marker on the binding pad. Then, according to the project needs, the time can be selected to control the test progress.

[0018] In this structure, since the sample and the marker are added in a step - by - step manner, the substance to be detected in the sample first binds to the antigen / antibody on the T line of the membrane, and then releases the marker on the binding pad as a chromogenic agent to combine with the T line. Operationally, the sample can be further quantitatively processed, and it is ensured that the detected concentration is positively correlated with the concentration of the substance to be detected bound to the NC membrane.

[0019] The obvious advantages of this method compared with the traditional double - antigen sandwich / double - antibody sandwich method are that it is not easy to cause HOOK due to the too high concentration of the substance to be detected in the sample, resulting in a low test value, and it can accurately detect the substance to be detected in the case of high - interference substances in the sample.

[0020] The technical solution of the embodiment of the present utility model has at least the following advantages and beneficial effects:

[0021] 1. The utility model uses an isolation film to separate the sample pad and the binding pad, enabling the sample and the marker to chromatograph separately, and it is not easy to cause HOOK due to the too high concentration of the substance to be detected in the sample, resulting in a low test value.

[0022] 2. After the sample liquid chromatographs to the designated position on the NC membrane, the utility model adds the marker washing liquid, which can fix the amount of the sample liquid participating in the reaction and improve the reagent performance.

[0023] 3. The utility model adds a layer of isolation film between the binding pad and the sample pad, which can control the experimental progress. Description of the Drawings

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present utility model, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0025] Figure 1 It is a schematic side structure diagram of a chromatographic test strip provided by the prior art;

[0026] Figure 2 It is a schematic side structure diagram of a device for detecting antibodies in a sample provided in Embodiment 1 of the present invention;

[0027] Figure 3 It is a schematic partial structure diagram of a device for detecting antibodies in a sample provided in Embodiment 1 of the present invention;

[0028] Reference numerals: 1, bottom plate; 2, sample pad; 3, binding pad; 4, test line T; 5, quality control line C; 6, NC membrane; 61, sample application area; 62, reaction area; 7, absorption pad; 8, isolation film. Detailed Embodiments

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the drawings in the embodiments of the present utility model. Obviously, the described embodiments are some, but not all, of the embodiments of the present utility model. Usually, the components of the embodiments of the present utility model described and illustrated in the drawings here can be arranged and designed in various different configurations.

[0030] Accordingly, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts fall within the scope of protection of the present invention.

[0031] It should be noted that like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0032] In the description of the present invention, it should be noted that if terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of this application is usually placed during use, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0033] In the description of the present invention, it should also be noted that unless otherwise clearly specified and defined, if terms such as "set", "installed", "connected", "coupled" are to be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0034] Embodiment 1

[0035] A device for detecting antibodies in a sample, comprising a bottom plate 1, a sample pad 2, a conjugate pad 3, an NC membrane 6, and an absorbent pad 7 provided on the bottom plate 1. The sample pad 2 is disposed between the conjugate pad 3 and the NC membrane 6, and an isolation membrane 8 for controlling the contact area between the conjugate pad 3 and the sample pad 2 is further provided between the conjugate pad 3 and the sample pad 2.

[0036] In this example, the area of the isolation membrane 8 is smaller than the contact area between the conjugate pad 3 and the sample pad 2.

[0037] In this example, the sample pad 2 is connected to the bottom plate 1, the NC membrane 6, and the conjugate pad 3, and the conjugate pad 3 and the NC membrane 6 partially overlap in the vertical direction.

[0038] In this example, the NC membrane 6 is provided with a test line T4 and a quality control line C5.

[0039] In this example, the absorbent pad 7 is connected to the bottom plate 1 and the NC membrane 6.

[0040] In this example, the conjugate pad 3 is provided with a label for binding to the analyte in the sample.

[0041] Working principle and usage method:

[0042] During use, first add the sample to the sample pad 2, and let the sample chromatograph through the sample pad 2, the NC membrane 6, and the absorbent pad 7 in sequence;

[0043] When the sample chromatographs to a specific position, add the rinsing solution to the conjugate pad 3, and the rinsing solution chromatographs through the conjugate pad 3, the NC membrane 6, and the absorbent pad 7 in sequence.

[0044] In this structure, the analyte (antigen / antibody) in the sample first binds to the antigen / antibody coated on the test line T4, and the rinsing solution releases the label in the conjugate pad 3, thereby realizing that the label signal is positively correlated with the concentration of the analyte in the sample, so as to achieve the purpose of quantification.

[0045] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A device for detecting antibodies in a sample, comprising a bottom plate (1), a sample pad (2), a conjugate pad (3), an NC membrane (6) and an absorbent pad (7) provided on the bottom plate (1), characterized in that: The sample pad (2) is disposed between the conjugate pad (3) and the NC membrane (6), and an isolation membrane (8) for precisely controlling the chromatographic direction of the sample is further provided between the conjugate pad (3) and the sample pad (2).

2. The device for detecting antibodies in a sample according to claim 1, characterized in that: The area of the isolation membrane (8) is smaller than the contact area between the conjugate pad (3) and the sample pad (2).

3. A device for detecting antibodies in a sample according to claim 1 or 2, characterized in that: The sample pad (2) is connected to the bottom plate (1), the NC membrane (6) and the conjugate pad (3), and the conjugate pad (3) and the NC membrane (6) partially overlap in the vertical direction.

4. A device for detecting antibodies in a sample according to claim 1 or 2, characterized in that: The NC membrane (6) is provided with a test line T (4) and a control line C (5).

5. A device for detecting antibodies in a sample according to claim 1 or 2, characterized in that: The absorbent pad (7) is connected to the bottom plate (1) and the NC membrane (6).

6. The device for detecting antibodies in a sample according to claim 1 or 2, characterized in that: The conjugate pad (3) is provided with a marker for binding to the substance to be detected in the sample.

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