A microfluidic chip for immunoassay

Abstract

The present application relates to a microfluidic chip for immunoassay, comprising a base plate and a cover plate covering the base plate, wherein the cover plate is provided with a sample addition area, the upper surface of the base plate is provided with a first cavity, a labeling area, a detection area, and a waste liquid area, and the first cavity is provided with a fixedly connected mixing device and a mixing area; in the present application, the mixing device drives the sample and the diluent in the mixing area to be fully mixed to ensure good repeatability of the detection results; the ingenious connection of the sample addition area, the mixing area, the labeling area, and the detection area and the coordinated action of the control center, the microvalve, and the motor solve the problem of insufficient mixing of the sample and the diluent in the microfluidic chip; in addition, the setting of the hole cover can ensure a better reagent reaction environment; the setting of multiple sub-detection areas can detect a large number of antigen substances; using the microfluidic chip of the present application for immunoassay can better solve the problem of poor repeatability of the detection results caused by uneven mixing of existing samples, and is also suitable for large-scale clinical diagnosis.

Description

Technical Field

[0001] The present application belongs to the technical field of microfluidic chips and relates to a microfluidic chip for immune detection. Background Art

[0002] Microfluidic chips concentrate all the operational steps in traditional laboratories, such as sample preparation, reaction, separation, and detection, on the chip, requiring only a small amount of biological specimens or reagents. Its reaction system is small, the specific surface area is large, and the diffusion distance of reactants is short, thereby increasing the opportunity for intermolecular interaction, shortening the reaction time, and having high sensitivity, it can measure low-concentration markers. Because it is easy to integrate and automate, it can eliminate tedious manual operations and reduce the chance of contamination. Its high-throughput nature allows for multiple parallel tests to be performed simultaneously on a single chip, creating the possibility of auxiliary diagnosis for a variety of clinical diseases. In addition, the micro-analysis platform has a low manufacturing cost and a small size, making it easy to carry. Using this platform, medical workers can quickly complete tests in resource-scarce medical environments without sending specimens to a central laboratory, meeting the needs of POCT diagnosis.

[0003] Microfluidic chips offer advantages such as high sensitivity, high throughput, and automation, making them well-suited for clinical point-of-care diagnostics. Microfluidic immunochips developed based on microfluidic technology and immunoassays have become a research hotspot in recent years, with significant achievements in tumor marker detection, infectious disease antigen and antibody detection, autoantibody detection, and hormone detection. However, numerous challenges remain to be overcome during chip development, such as poor reproducibility of test results due to uneven sample mixing. Summary of the Invention

[0004] In order to solve the above-mentioned problems existing in the art, the present application aims to provide a microfluidic chip for immunoassay, which can solve the problem of poor repeatability of test results due to uneven sample mixing. The microfluidic chip of the present application can not only be used for conventional immunoassay, but also is suitable for large-scale clinical diagnosis.

[0005] The technical solutions of the present invention are as follows:

[0006] A microfluidic chip for immune detection, comprising a base plate and a cover plate covering the base plate;

[0007] Furthermore, a sample adding area is provided on the cover plate;

[0008] Furthermore, the upper surface of the bottom plate is provided with a first cavity, a marking area, a detection area, and a waste liquid area;

[0009] Furthermore, the sample adding area includes a first containing tank, a first through hole, a hole cover, a first pipeline, a second pipeline, and a third pipeline;

[0010] Furthermore, a fixedly connected mixing device and a mixing zone are provided in the first cavity.

[0011] In some embodiments, the first through hole and the hole cover are located in the first receiving groove, a rotating shaft is provided on the first side of the first receiving groove, the first side of the hole cover is fixedly connected to the rotating shaft, the rotating shaft is sleeved on a rotating shaft fixing portion, and both ends of the rotating shaft fixing portion are respectively fixedly connected to the sidewalls of the first receiving groove, a first notch is provided on the second side of the first receiving groove, and a first protrusion is provided on the second side of the hole cover at a position corresponding to the first notch, and the first protrusion is engaged with the first notch;

[0012] Furthermore, the first through hole is connected to the mixing zone in the first cavity through the first pipeline, the second pipeline, and the third pipeline. The first pipeline is vertically arranged, the second pipeline is inclined, and the third pipeline is horizontally arranged. A first microvalve is provided at the other end of the third pipeline.

[0013] In some embodiments, the mixing zone is provided with a first microtube connected to the third pipeline, the first microtube is located at the upper end of the mixing zone, a second microvalve is provided in the first microtube, and the first microtube cooperates with the third pipeline.

[0014] In some embodiments, the mixing device includes a motor, a disc, and a fixed base, and the fixed base includes a first fixed base, a second fixed base, a third fixed base, and a fourth fixed base. The first fixed base is fixedly connected to the bottom of the first cavity, the first fixed base is vertically arranged, and the second fixed base is horizontally arranged. The upper end of the first fixed base is fixedly connected to the second fixed base, and a motor shaft hole is provided in the middle part of the second fixed base. The motor shaft of the motor passes through the motor shaft hole and is fixedly connected to the disc. The two ends of the second fixed base are respectively connected to the third fixed base and the fourth fixed base, the third fixed base is provided with a third through hole, and the fourth fixed base is provided with a fourth through hole.

[0015] In some embodiments, the mixing device further includes a first fixing post and a second fixing post, wherein the first fixing post passes through a third through-hole and is fixedly connected to one side of the first fixing frame, and the second fixing post passes through a fourth through-hole and is fixedly connected to the other side of the first fixing frame, the first fixing post and the third through-hole are loosely fitted, the second fixing post and the fourth through-hole are loosely fitted, and a fifth through-hole is provided in the first fixing frame, the cross-section of the fifth through-hole being an elongated strip.

[0016] Furthermore, a second protrusion is fixedly provided on a side of the disc facing away from the motor shaft, the cross section of the second protrusion is cylindrical, the second protrusion and the fifth through hole are transitionally matched, and the diameter of the second protrusion is equal to the width of the fifth through hole;

[0017] Furthermore, the lower end of the mixing zone is fixedly connected to the upper end of the first fixing frame;

[0018] Furthermore, the mixing zone includes a second microtube connected to the fourth pipeline, the second microtube is located at the lower end of the mixing zone, a third microvalve is provided in the second microtube, and the second microtube cooperates with the fourth pipeline;

[0019] Furthermore, a fourth microvalve is provided at the end of the fourth pipeline that contacts the second microtube.

[0020] In some embodiments, the other end of the fourth pipeline is connected to the upper end of the marking area, the marking area is provided with a first antibody, and the lower end of the marking area opposite to the fourth pipeline is provided with a fifth pipeline, and the fifth pipeline is provided with a fifth microvalve.

[0021] In some embodiments, the detection zone is provided with a plurality of sub-detection zones, each of which is provided with a detection card, the detection card having a plurality of detection strips, and each of the plurality of detection strips is coated with different second antibodies.

[0022] In some embodiments, the labeling area is coated with a quality control marker, the detection strip is provided with a quality control line, and the quality control line is coated with a quality control antibody.

[0023] In some embodiments, a control center is provided in the microfluidic chip, and the control center is wirelessly connected to the first microvalve, the second microvalve, the third microvalve, the fourth microvalve, and the motor.

[0024] The advantages of the present application are as follows: the mixing device in the present application drives the sample and the diluent to be fully mixed, so as to achieve the purpose of improving the repeatability of the detection and ensure the accuracy of the detection result; the problem of insufficient mixing of the sample and the diluent of the microfluidic chip is solved by the ingenious connection of the sample adding area, the mixing area, the labeling area and the detection area on the microfluidic chip and the coordinated action of the control center, the first microvalve, the second microvalve, the third microvalve, the fourth microvalve, the fifth microvalve and the motor; in addition, the setting of the hole cover can ensure a better reagent reaction environment; the setting of multiple sub-detection areas can detect a large number of antigen substances, and it is only necessary to coat the first antibody in the labeling area and the corresponding second antibody in the detection area to detect a variety of antigen substances. The inclined setting of the second pipeline ensures that the sample and the diluent can enter the mixing area under the action of gravity, and the inclined setting of each microchannel ensures that the liquid can flow to the sub-detection areas away from the first sub-detection area under the action of gravity, and finally flow into the waste liquid area; the use of the microfluidic chip of the present application for immunoassay can better solve the problem of poor repeatability of the detection results due to uneven sample mixing, and is also suitable for large-scale clinical diagnosis. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of this application;

[0026] Figure 2 is a schematic diagram of the first cavity;

[0027] Figure 3 is another schematic diagram of the first cavity;

[0028] Figure 4 is a schematic diagram of the first receiving tank;

[0029] Figure 5 is another schematic diagram of the first receiving tank;

[0030] Figure 6 The top view of the mixing device (based on Figure 1 location);

[0031] Figure 7 is a schematic diagram of the base plate;

[0032] Figure 8 for Figure 7 Schematic diagram of the middle AA section;

[0033] In the figure: 1, bottom plate; 2, cover plate; 3, first cavity; 4, marking area; 7, sample adding area; 8, mixing area; 9, mixing device; 201, first receiving groove; 202, first through hole; 203, hole cover; 204, first pipeline; 205, second pipeline; 206, third pipeline; 207, rotating shaft; 208, rotating shaft fixing portion; 209, first notch; 210, first protrusion; 211, first baffle; 212, third Second baffle; 213, first microvalve; 801, first microtube; 802, second microvalve; 901, motor; 902, disk; 903, first fixing seat; 904, second fixing seat; 905, third fixing seat; 906, fourth fixing seat; 907, motor shaft; 908, third through hole; 909, fourth through hole; 910, first fixing post; 911, second fixing post; 912, first fixing bracket; 913, second Protrusion; 914, fifth through hole; 915, second micro-tube; 916, third micro-valve; 41, fourth pipeline; 42, fourth micro-valve; 43, fifth pipeline; 44, fifth micro-valve; 51, first sub-detection area; 52, first left micro-channel; 53, first right micro-channel; 54, second left sub-detection area; 55, second right sub-detection area; 56, second left micro-channel; 57, third left micro-channel; 58, fourth left micro-channel; 59, Third left sub-detection area; 510, fourth left sub-detection area; 511, fifth left sub-detection area; 512, second right micro-channel; 513, third right micro-channel; 514, fourth right micro-channel; 515, third right sub-detection area; 516, fourth right sub-detection area; 517, fifth right sub-detection area; 518, detection card; 519, fifth left micro-channel; 520, fifth right micro-channel; 61, left waste liquid area; 62, right waste liquid area. DETAILED DESCRIPTION

[0034] The following examples are provided to illustrate the present invention in more detail, but they do not constitute a limitation of the present invention. The experimental methods in the following examples are conventional methods unless otherwise specified. The reagents used in the following examples are commercially available common reagents unless otherwise specified.

[0035] See also Figure 1 One embodiment of the present application provides a microfluidic chip for immunoassay, comprising a base plate 1 and a cover plate 2 covering the base plate 1, wherein the cover plate 2 is provided with a sample loading area 7; the upper surface of the base plate 1 is provided with a first cavity 3, a labeling area 4, a detection area, and a waste liquid area; the sample loading area 7 includes a first receiving groove 201, a first through hole 202, a hole cover 203, a first pipeline 204, a second pipeline 205, and a third pipeline 206;

[0036] The first cavity 3 is provided with a fixedly connected mixing device 9 and a mixing zone 8 .

[0037] like Figure 4-5As shown, the cover plate 2 is provided with a first through hole 202, and the first through hole 202 is used to add samples and diluents. In the prior art, the first through hole 202 is in direct contact with the outside air. If left for a long time, it is easy to have an adverse effect on the test results. In order to achieve a better reagent reaction environment, the present application is provided with a hole cover 203 that can cover the first through hole 202. The first through hole 202 and the hole cover 203 are located in the first receiving groove 201. A rotating shaft 207 is provided on the first side of the first receiving groove 201. The first side of the hole cover 203 is fixedly connected to the rotating shaft 207. The rotating shaft 207 is sleeved on the fixing portion of the rotating shaft 207. The rotating shaft 207 can rotate circumferentially on the fixing portion of the rotating shaft 207. The two ends of the fixing portion of the rotating shaft 207 are respectively fixedly connected to the side walls of the first receiving groove 201. A first notch 209 is provided on the second side of the first receiving groove 201. A first protrusion 210 is provided on the second side of the hole cover 203 at a position corresponding to the first notch 209. The first protrusion 210 is snap-fitted to the first notch 209.

[0038] Furthermore, a first blocking piece 211 and a second blocking piece 212 are further provided on the second side of the first accommodating groove 201. The first blocking piece 211 and the second blocking piece 212 are symmetrically arranged on both sides of the first accommodating groove 201 respectively. The first blocking piece 211 and the second blocking piece 212 are elastic. When the hole cover 203 covers the first through hole 202, the first blocking piece 211 and the second blocking piece 212 are located on the upper surface of the second side of the hole cover 203 to prevent the hole cover 203 from opening when the first protrusion 210 and the first notch 209 are not tightly connected. At the same time, since the first blocking piece 211 and the second blocking piece 212 are elastic, when the hole cover 203 needs to be opened, the force applied by the first blocking piece 211 and the second blocking piece 212 on the hole cover 203 is small, and the hole cover 203 can be opened with a little force.

[0039] In some embodiments, the first blocking piece 211 and the second blocking piece 212 are elastic rubber sheets.

[0040] Furthermore, in order to open the hole cover 203 more conveniently, the thickness of the second side surface of the hole cover 203 is smaller than the thickness of other parts of the hole cover 203 .

[0041] In this embodiment, the first through hole 202 is used to add samples and diluents. The first through hole 202 is connected to the mixing zone 8 in the first cavity 3 through a first pipeline 204, a second pipeline 205, and a third pipeline 206. The second pipeline 205 is located between the first pipeline 204 and the third pipeline 206. In order to facilitate the smooth entry of the sample or diluent into the mixing zone 8, the first pipeline 204 is arranged vertically, the second pipeline 205 is arranged obliquely, and the third pipeline 206 is arranged horizontally. One end of the third pipeline 206 is connected to the second pipeline 205, and the other end of the third pipeline 206 is provided with a first microvalve 213.

[0042] Furthermore, the first pipeline 204 , the second pipeline 205 , and the third pipeline 206 are located in the cover plate 2 .

[0043] In this embodiment, the mixing zone 8 is provided with a first microtube 801 connected to the third pipeline 206, and the first microtube 801 is located at the upper end of the mixing zone 8. A second microvalve 802 is provided in the first microtube 801. Furthermore, when the first microtube 801 contacts the third pipeline 206, the first microtube 801 cooperates with the third pipeline 206. In order to prevent liquid from seeping out when flowing from the third pipeline 206 to the first microtube 801, in some embodiments, the aperture of the first microtube 801 may be slightly larger than the aperture of the third pipeline 206, and the third pipeline 206 is partially located in the first microtube 801; in other embodiments, the aperture of the first microtube 801 is equal to the aperture of the third pipeline 206, and the contact surface between the first microtube 801 and the third pipeline 206 has an elastic sealing ring.

[0044] In this embodiment, see Figure 2 、 3 6. The first cavity 3 is partially located on the lower surface of the cover plate 2 and partially located on the upper surface of the bottom plate 1. A mixing device is provided in the first cavity 3. The mixing device is fixedly connected to the mixing zone. The mixing device drives the liquid in the mixing zone to shake back and forth to achieve the purpose of final mixing.

[0045] Specifically, the mixing device includes a motor 901, a disc 902, and a fixed seat. The fixed seat includes a first fixed seat 903, a second fixed seat 904, a third fixed seat 905, and a fourth fixed seat 906, wherein the first fixed seat 903 is fixedly connected to the bottom of the first cavity 3, the first fixed seat 903 is vertically arranged, the second fixed seat 904 is horizontally arranged, the first fixed seat 903 is parallel to the thickness direction of the microfluidic chip, the second fixed seat 904 is parallel to the length direction of the microfluidic chip, the upper end of the first fixed seat 903 is fixedly connected to the second fixed seat 904, and the second fixed seat 905 is horizontally arranged. The middle part of the fixed seat 904 is provided with a motor 901 shaft hole, and the motor 901 shaft of the motor 901 passes through the motor 901 shaft hole and is fixedly connected to the disc 902. The two ends of the second fixed seat 904 are respectively connected to the third fixed seat 905 and the fourth fixed seat 906. The third fixed seat 905 and the fourth fixed seat 906 are parallel to each other and perpendicular to the second fixed seat 904. The third fixed seat 905 and the fourth fixed seat 906 extend toward the disc 902. The third fixed seat 905 is provided with a third through hole 908, and the fourth fixed seat 906 is provided with a fourth through hole 909.

[0046] Furthermore, the mixing device also includes a first fixed column 910 and a second fixed column 911, wherein the first fixed column 910 passes through the third through hole 908 and is fixedly connected to one side of the first fixed frame 912, and the second fixed column 911 passes through the fourth through hole 909 and is fixedly connected to the other side of the first fixed frame 912, the first fixed column 910 and the third through hole 908 are clearance fit, the second fixed column 911 and the fourth through hole 909 are clearance fit, and a fifth through hole 914 is provided in the first fixed frame 912, and the cross-section of the fifth through hole 914 is an elongated strip; a second protrusion 913 is fixedly provided on the side of the disc 902 facing away from the shaft of the motor 901, the cross-section of the second protrusion 913 is cylindrical, the second protrusion 913 and the fifth through hole 914 are transition fit, and the diameter of the second protrusion 913 is equal to the width of the fifth through hole 914. Specifically, when the motor 901 shaft drives the disk 902 to rotate, the second protrusion 913 rotates together with the disk 902, thereby driving the first fixing frame 912 to move left and right along the length direction of the microfluidic chip. That is, when the second protrusion 913 rotates with the disk 902 to the point closest to the fourth through hole 909 (see FIG. Figure 2 ), the first fixing frame 912 also moves horizontally to the position closest to the fourth through hole 909; when the second protrusion 913 rotates with the disk 902 to the position closest to the bottom of the first cavity 3, the first fixing frame 912 returns to the center position of the disk 902; when the second protrusion 913 rotates with the disk 902 to the position closest to the third through hole 908 (see Figure 3 ), the first fixing frame 912 also moves horizontally to the position closest to the third through hole 908.

[0047] In order to improve the mixing effect of the mixing zone 8, the lower end of the mixing zone 8 is fixedly connected to the upper end of the first fixed frame 912, so that when the first fixed frame 912 moves horizontally, the mixing zone 8 moves horizontally following the first fixed frame 912, and the liquid in the mixing zone 8, that is, the mixture of the sample and the diluent, shakes back and forth with the horizontal movement, thereby improving the mixing effect. In order to further improve the mixing effect, the speed of the motor 901 can be increased, thereby driving the liquid in the mixing zone 8 to shake fully.

[0048] In other embodiments of the present application, bumps that improve the mixing effect can be set on the bottom and side walls of the mixing zone 8. The bumps can be of various shapes, such as cylindrical, hemispherical, cube, etc.; freely movable mixing balls can also be set in the mixing zone 8. The mixing balls can be spherical springs, solid balls, etc., and the number of mixing balls is arbitrary.

[0049] In this embodiment, the mixing zone 8 includes a second microtube 915 that can communicate with the fourth conduit 41. To facilitate the mixed liquid entering the marking zone 4, the second microtube 915 is located at the lower end of the mixing zone 8 and is provided with a third microvalve 916. Furthermore, when the second microtube 915 contacts the fourth conduit 41, the second microtube 915 and the fourth conduit 41 cooperate. To prevent leakage of liquid when flowing from the second microtube 915 to the fourth conduit 41, in some embodiments, the aperture of the fourth conduit 41 can be slightly larger than the aperture of the second microtube 915, with the second microtube 915 partially located in the fourth conduit 41. In other embodiments, the aperture of the second microtube 915 is equal to the aperture of the fourth conduit 41. Preferably, an elastic sealing ring is provided at the contact surface between the second microtube 915 and the fourth conduit 41. The end of the fourth conduit 41 that contacts the second microtube 915 is provided with a fourth microvalve 42 to facilitate controlling the mixed liquid from entering the marking zone 4.

[0050] In this embodiment, the other end of the fourth pipeline 41 is connected to the upper end of the marking area 4, and the first antibody is provided in the marking area 4. A fifth pipeline 43 is provided at the lower end of the other side of the marking area 4 opposite to the fourth pipeline 41. A fifth microvalve 44 is provided on the fifth pipeline 43. After the antigen in the mixed solution fully reacts with the first antibody to form a first antibody-antigen complex, the complex flows into the detection area along the fifth pipeline 43.

[0051] Specifically, if Figure 7-8As shown, the detection area is provided with a plurality of sub-detection areas, and the plurality of sub-detection areas are coated with the same or different second antibodies. The sub-detection area directly connected to the fifth pipeline 43 is the first sub-detection area 51, and the two sides of the first sub-detection area 51 are provided with a first left micro-channel 52 and a first right micro-channel 53. The first left micro-channel 52 and the first right micro-channel 53 are inclined. The connection between the first left micro-channel 52, the first right micro-channel 53 and the first sub-detection area 51 is higher than any other part of the first left micro-channel 52 and the first right micro-channel 53. The first left micro-channel 52 is connected to the second left sub-detection area 54, and the first right micro-channel 53 is connected to the second right sub-detection area 55, that is, the second left sub-detection area 54 and the second The height of the right sub-detection area 55 is lower than that of the first sub-detection area 51; a second left micro-channel 56 is provided on the other side of the second left sub-detection area 54 opposite to the first left micro-channel 52, and the second left micro-channel 56 is inclined. The connection between the second left micro-channel 56 and the second left sub-detection area 54 is higher than any other part of the second left micro-channel. The second left micro-channel 56 is connected to the third left sub-detection area 59, that is, the height of the third left sub-detection area 59 is lower than that of the second left sub-detection area 54; a third left micro-channel 57 is provided on the other side of the third left sub-detection area 59 opposite to the second left micro-channel 56, and the third left micro-channel 57 is inclined. The connection between the third left micro-channel 57 and the third left sub-detection area 59 is higher than any other part of the third left micro-channel. The third left micro-channel 57 is connected to the fourth left sub-detection area 510, that is, the height of the fourth left sub-detection area 510 is lower than the third left sub-detection area 59; the fourth left micro-channel 58 is provided on the other side of the fourth left sub-detection area 510 opposite to the third left micro-channel 57, and the fourth left micro-channel 58 is inclined. The connection between the fourth left micro-channel 58 and the fourth left sub-detection area 510 is higher than any other part of the fourth left micro-channel, and the fourth left micro-channel 58 is connected to the fifth left sub-detection area 511, that is, the height of the fifth left sub-detection area 511 is lower than the fourth left sub-detection area 510; similarly, the second right micro-channel 512 is provided on the other side of the second right sub-detection area 55 opposite to the first right micro-channel 53, and the second right micro-channel 513 is provided. 12 is arranged obliquely, the connection between the second right micro-channel 512 and the second right sub-detection area 55 is higher than any other part of the second right micro-channel, and the second right micro-channel 512 is connected to the third right sub-detection area 515, that is, the height of the third right sub-detection area 515 is lower than the second right sub-detection area 55; the third right micro-channel 513 is provided on the other side of the third right sub-detection area 515 opposite to the second right micro-channel 512, and the third right micro-channel 513 is arranged obliquely, the connection between the third right micro-channel 513 and the third right sub-detection area 515 is higher than any other part of the third right micro-channel, and the third right micro-channel 513 is connected to the fourth right sub-detection area 516, that is, the height of the fourth right sub-detection area 516 is lower than the third right sub-detection area 515;A fourth right micro-channel 514 is provided on the other side of the fourth right sub-detection zone 516 opposite the third right micro-channel 513. The fourth right micro-channel 514 is arranged at an angle, and the connection between the fourth right micro-channel 514 and the fourth right sub-detection zone 516 is higher than any other part of the fourth right micro-channel 514. The fourth right micro-channel 514 is connected to the fifth right sub-detection zone 517. In other words, the height of the fifth right sub-detection zone 517 is lower than that of the fourth right sub-detection zone 516.

[0052] In another embodiment of the present application, a test card 518 is provided within the multiple sub-test zones. The test card 518 includes multiple test strips. The multiple test strips are coated with different detection antibodies (secondary antibodies), and the detection antibodies correspond to the types and quantities of the labeled antibodies. In the test zones, the first antibody-antigen complex forms a ternary complex of the first antibody-antigen (i.e., analyte)-secondary antibody with the detection antibodies on the test strips.

[0053] Furthermore, there is one detection strip, and each detection strip is coated with one detection antibody, that is, each sub-detection area can detect one antigen, and the detection area can detect 9 antigens.

[0054] In another embodiment of the present application, there are two detection strips, each of which is coated with one detection antibody, that is, each sub-detection area can detect two antigens, and the detection area can detect 18 antigens.

[0055] In another embodiment of the present application, there are three detection strips, and each detection strip is coated with one detection antibody, that is, each sub-detection area can detect three antigens, and the detection area can detect 27 antigens.

[0056] In another embodiment of the present application, there are two detection strips, each of which is coated with the same detection antibody, and the detection area can detect one antigen. This detection method can be used to maximize the repeatability of the microfluidic chip and to detect the mixing effect of the mixing area 8.

[0057] In one embodiment, a quality control marker is coated within the marking region 4, and a quality control line is provided on the detection strip, which is coated with a quality control antibody. The quality control marker specifically binds to the quality control antibody to form a quality control marker-quality control antibody complex. The validity of the test results of the microfluidic chip is determined by detecting the quality control marker-quality control antibody complex.

[0058] In addition, in order to facilitate the collection of waste liquid, the detection area also includes a left waste liquid area 61 and a right waste liquid area 62. The left waste liquid area 61 is connected to the fifth left sub-detection area 511 through the fifth left micro-channel. Similarly, the fifth left micro-channel 519 is inclined, and the connection between the fifth left micro-channel and the fifth left sub-detection area 511 is higher than any other part of the fifth left micro-channel 519, that is, the height of the left waste liquid area 61 is lower than the fifth left sub-detection area 511; correspondingly, the right waste liquid area 62 is connected to the fifth right sub-detection area 517 through the fifth right micro-channel. Similarly, the fifth right micro-channel 520 is inclined, and the connection between the fifth right micro-channel 520 and the fifth right sub-detection area 517 is higher than any other part of the fifth right micro-channel, that is, the height of the right waste liquid area 62 is lower than the fifth right sub-detection area 517.

[0059] Specifically, the detection area and the marking area 4 are both located on the upper surface of the bottom plate 1 (eg Figure 7 shown).

[0060] In this embodiment, a control center is provided in the microfluidic chip, and the control center is wirelessly connected to the first microvalve 213 , the second microvalve 802 , the third microvalve 916 , the fourth microvalve 42 , the fifth microvalve 44 , and the motor 901 , preferably via Bluetooth. This embodiment also provides a method for using the above-mentioned microfluidic chip, that is, first open the hole cover, add the sample and the diluent into the first through hole in sequence, and after the sample addition is completed, cover the hole cover; the control center controls the motor to operate, and the motor drives the disc to rotate. When the second protrusion rotates with the disc to the rightmost side (the position closest to the fourth through hole), that is, the mixing zone contacts the third pipeline, the control center controls the first microvalve and the second microvalve to open, and the sample and the diluent enter the mixing zone. After all enter, the first microvalve and the second microvalve are closed, and the third microvalve is in a closed state. The control center controls the motor to start working, and the motor shaft drives the disc to rotate. The second protrusion set on the disc moves circumferentially with the disc, the second protrusion drives the first fixed frame to move left and right, and the first fixed frame drives the mixing zone to move left and right, and the liquid in the mixing zone shakes back and forth, thereby achieving the purpose of mixing; after the mixture is evenly mixed, , the mixing area stops moving, the fourth pipeline contacts the mixing area, the control center controls the third microvalve and the fourth microvalve to open, the mixed liquid enters the labeling area along the fourth pipeline, and forms a first antibody-antigen complex with the labeled first antibody in the labeling area. The control center controls the fifth microvalve to open, and the complex enters the detection area along the fifth pipeline, passes through the first sub-detection area, and then flows into the second left detection area, the second right detection area...the fifth right detection area arranged in the first sub-detection area in sequence. By detecting the amount of the ternary complex in the detection area, the content of the analyte in the sample is calculated, and the mixed liquid that is not bound to the second antibody flows into the left waste liquid area and the right waste liquid area. The quality control marker specifically binds to the quality control antibody on the quality control line to form a quality control marker-quality control antibody complex. The effectiveness of the microfluidic chip is determined by detecting the quality control marker-quality control antibody complex in the detection cavity.

[0061] The mixing device in the present application drives the sample and the diluent to be fully mixed, so as to achieve the purpose of improving the repeatability of the detection and ensure the accuracy of the detection results; the problem of insufficient mixing of the sample and the diluent in the microfluidic chip is solved through the ingenious connection of the mixing area, the labeling area, and the detection area on the microfluidic chip and the coordinated action of the control center, the first microvalve, the second microvalve, the third microvalve, the fourth microvalve, the fifth microvalve, and the motor; in addition, the setting of the hole cover can ensure a better reagent reaction environment; the setting of multiple sub-detection areas can detect a large number of antigen substances. It is only necessary to coat the first antibody in the labeling area and the corresponding second antibody in the detection area to detect multiple antigen substances. The inclined setting of the second pipeline ensures that the sample and diluent can enter the mixing area under the action of gravity. At the same time, the inclined setting of each microchannel (first left microchannel, first right microchannel...) ensures that the liquid can flow to the sub-detection areas away from the first sub-detection area under the action of gravity, and finally flow into the waste liquid area; using the microfluidic chip of the present application for immunoassay can better solve the problem of poor repeatability of test results caused by uneven sample mixing, and is also suitable for large-scale clinical diagnosis.

[0062] When terms such as "vertical," "horizontal," "left," "right," "upper," "lower," "inner," "outer," and "bottom" are used to indicate an orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings and are for ease of description only. They do not indicate or imply that the device or element referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be understood as limitations on this application. In addition, the terms "first," "second," and the like are used for descriptive purposes only and should not be understood to indicate or imply relative importance. The term "and / or" includes any and all combinations of one or more of the relevant listed items.

[0063] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0064] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and such modifications and improvements are all within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A microfluidic chip for immunoassay, characterized in that: It includes a base plate and a cover plate covering the base plate; The cover plate is provided with a sample adding area; The upper surface of the bottom plate is provided with a first cavity, a marking area, a detection area, and a waste liquid area; The sample adding area includes a first containing tank, a first through hole, a hole cover, a first pipeline, a second pipeline, and a third pipeline; The first cavity is provided with a fixedly connected mixing device and a mixing zone; The mixing device includes a motor, a disc, and a fixed base, wherein the fixed base includes a first fixed base, a second fixed base, a third fixed base, and a fourth fixed base, wherein the first fixed base is fixedly connected to the bottom of the first cavity, the first fixed base is vertically arranged, and the second fixed base is horizontally arranged, the upper end of the first fixed base is fixedly connected to the second fixed base, a motor shaft hole is provided in the middle portion of the second fixed base, the motor shaft of the motor passes through the motor shaft hole and is fixedly connected to the disc, the two ends of the second fixed base are respectively connected to the third fixed base and the fourth fixed base, the third fixed base is provided with a third through hole, and the fourth fixed base is provided with a fourth through hole; The mixing device further includes a first fixing post and a second fixing post, wherein the first fixing post passes through a third through-hole and is fixedly connected to one side of the first fixing frame, and the second fixing post passes through a fourth through-hole and is fixedly connected to the other side of the first fixing frame, the first fixing post and the third through-hole are clearance-fitted, the second fixing post and the fourth through-hole are clearance-fitted, and a fifth through-hole is provided in the first fixing frame, the cross-section of the fifth through-hole being an elongated strip; A second protrusion is fixedly provided on the side of the disc facing away from the motor shaft. The cross section of the second protrusion is cylindrical. The second protrusion and the fifth through hole are in transition fit. The diameter of the second protrusion is equal to the width of the fifth through hole. The lower end of the mixing zone is fixedly connected to the upper end of the first fixing frame; The mixing zone includes a second microtube connected to a fourth pipeline, the second microtube is located at the lower end of the mixing zone, a third microvalve is provided in the second microtube, and the second microtube cooperates with the fourth pipeline; the end of the fourth pipeline in contact with the second microtube is provided with a fourth microvalve, and the other end of the fourth pipeline is connected to the upper end of the marking zone; The mixing zone is provided with a first microtube connected to the third pipeline. The first microtube is located at the upper end of the mixing zone. A second microvalve is provided in the first microtube. The first microtube cooperates with the third pipeline.

2. A microfluidic chip for immunoassay according to claim 1, characterized in that: The first through hole and the hole cover are located in the first receiving groove, a rotating shaft is provided on the first side surface of the first receiving groove, the first side surface of the hole cover is fixedly connected to the rotating shaft, the rotating shaft is sleeved on the rotating shaft fixing portion, and the two ends of the rotating shaft fixing portion are respectively fixedly connected to the side walls of the first receiving groove, a first notch is provided on the second side surface of the first receiving groove, and a first protrusion is provided on the second side surface of the hole cover at a position corresponding to the first notch, and the first protrusion is engaged with the first notch; The first through hole is connected to the mixing zone in the first cavity through the first pipeline, the second pipeline, and the third pipeline. The first pipeline is vertically arranged, the second pipeline is inclined, and the third pipeline is horizontally arranged. A first microvalve is provided at the other end of the third pipeline.

3. The microfluidic chip for immunoassay according to claim 1, characterized in that: A first antibody is provided in the marking area, a fifth pipeline is provided at the lower end of the other side of the marking area opposite to the fourth pipeline, and a fifth microvalve is provided on the fifth pipeline.

4. The microfluidic chip for immunoassay according to claim 1, characterized in that: The detection area is provided with a plurality of sub-detection areas, the plurality of sub-detection areas are provided with a detection card, the detection card is provided with a plurality of detection strips, and the plurality of detection strips are coated with different second antibodies.

5. The microfluidic chip for immunoassay according to claim 4, characterized in that: The marking area is coated with a quality control marker, the detection strip is provided with a quality control line, and the quality control line is coated with a quality control antibody.

6. The microfluidic chip for immunoassay according to claim 1, characterized in that: A control center is provided in the microfluidic chip, and the control center is wirelessly connected to the first microvalve, the second microvalve, the third microvalve, the fourth microvalve, and the motor.

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