Multi-target nucleic acid detection device and detection method based on constant temperature expansion test strip

Abstract

The present invention discloses a multi-target nucleic acid detection device and a detection method based on a constant temperature amplification test strip. The device comprises: an enzyme reaction and a test strip detection component, wherein the enzyme reaction and the test strip detection component are configured to form a sealed chamber in which liquid can flow, wherein the formed sealed chamber comprises an enzyme reaction chamber, a diluent injection chamber and a test strip lateral flow chromatography chamber, wherein the enzyme reaction chamber, the diluent injection chamber and the test strip lateral flow chromatography chamber realize constant temperature amplification enzyme reaction, enzyme reaction product dilution and lateral flow chromatography through a liquid channel; in the present invention, multiple nucleic acid targets can be detected simultaneously, and by integrating the enzyme reaction and the test strip detection component with the constant temperature amplification incubation component, the entire detection process is made simpler to operate and more convenient to use, thereby facilitating the rapid detection technology to enter households for self-testing.

Description

Technical Field

[0001] The present invention relates to the technical field of rapid detection of nucleic acid molecules for gene detection, and in particular to a multi-target nucleic acid detection device and a detection method based on a constant temperature expansion test strip. Background Art

[0002] Isothermal amplification technology (RPA, RAA, ERA, MI RA, LAMP, RCA, etc.) can amplify and enrich the target molecules of the sample to be tested on a large scale. The optimal reaction temperature is generally in the range of 37°C to 65°C. The amplification speed is fast and the amplification reaction can be completed in 10-30 minutes. A large number of nucleic acid target molecules will be generated after amplification, which is easy to form nucleic acid aerosol contamination. There are two different detection technology schemes for the amplified products: 1. Based on the NfO probe method: The primers in the original system are labeled with FAM groups and biotin groups respectively. After the product is formed, the FAM group and the biotin group are combined together (forming a complete reporter molecule), and then the nucleic acid detection test strip is used for chromatography. If there is a target gene, a product with both FAM groups and biotin groups at both ends is formed. Two bands (C line and T line) will be formed on the nucleic acid detection test strip. If there is no target molecule, there is no product with both FAM groups and biotin groups at both ends in the system. Only one band (C line) will be displayed during the chromatography detection on the nucleic acid detection test strip; 2. Based on CRI SPR detection method: A large number of target molecules are obtained through isothermal amplification. After the target molecules specifically bind to crRNA, the Cas enzyme cleavage activity is activated, and then the Reporter in the reaction system is cleaved. The cleaved Reporter molecules will form two bands (C line and T line) when chromatographed on the CRISPR special nucleic acid detection test strip. On the contrary, if there is no target molecule, the cleavage characteristics of the Cas enzyme cannot be activated. The complete Reporter will only show one band (C line) when chromatographed on the CRISPR special nucleic acid detection test strip, thereby realizing the detection of the target molecule.

[0003] The constant temperature expansion test strip detection technology has the convenience of antigen detection technology and the sensitivity of qPCR detection technology or (and) the specificity of gene editing. This technology can be used for rapid, large-scale equipment-independent, and highly sensitive detection of nucleic acid target molecules. It is an advanced molecular POCT (point-of-care testing) technology with a wide range of application prospects in the fields of in vitro diagnostic reagent development, rapid pathogen detection, and animal disease detection.

[0004] At present, the commonly used technical means is to dilute the reaction liquid system after isothermal amplification with about 10 times diluent and then insert it into the nucleic acid detection test strip for chromatography and color development. This process requires the isothermal amplification reaction system to be exposed to the air. A large number of nucleic acid aerosol molecules produced by isothermal amplification will enter the environment, resulting in a large amount of nucleic acid aerosol pollution in the environment. These aerosol molecules greatly increase the probability of false positives in subsequent tests, affecting the test results of other tests. At the same time, these experimental operations require the operator to prepare the enzyme reaction system. This operation requires the use of pipettes and reagent consumables. The operator has high technical requirements and knowledge level, is difficult, and the operation process is cumbersome. Some engineers have developed devices for isothermal amplification and test strip detection technology, but only one target can be detected at a time, and the information obtained from the test results is too little, which is not conducive to subsequent application development. At the same time, the operation is still not streamlined, automated, and convenient enough, which is still an obstacle for related technologies and products to enter home self-testing. Summary of the invention

[0005] The main purpose of the present invention is to provide a multi-target nucleic acid detection device and a detection method based on a constant temperature expansion test strip, aiming to solve the existing technical problems.

[0006] To achieve the above object, the present invention provides a multi-target nucleic acid detection device based on a constant temperature expansion test strip, comprising:

[0007] An enzyme reaction and test strip detection component, wherein the enzyme reaction and test strip detection component is configured to form a sealed chamber in which liquid can flow, wherein the sealed chamber comprises an enzyme reaction chamber, a diluent injection chamber and a test strip lateral flow chromatography chamber, wherein the enzyme reaction chamber, the diluent injection chamber and the test strip lateral flow chromatography chamber realize isothermal amplification enzyme reaction, enzyme reaction product dilution and lateral flow chromatography through a liquid channel.

[0008] Furthermore, a magnetic stirrer is preset in the enzyme reaction chamber, a freeze-dried ball storage hole for pre-set enzyme reaction freeze-dried balls is provided on the upper part of the enzyme reaction chamber, the freeze-dried ball storage hole is connected to the enzyme reaction chamber through an oblique channel, and the freeze-dried ball storage hole and the enzyme reaction chamber are separated by a rubber tube plug, and a sample nucleic acid release and loading module is provided on the upper part of the enzyme reaction chamber, and the sample nucleic acid release and loading module forms a sealed space with the enzyme reaction chamber after insertion.

[0009] Furthermore, the diluent injection chamber is formed into a chamber by a cylindrical sleeve and an injection piston, the upper part of the chamber is connected to the enzyme reaction chamber through a pipeline, the connection between the chamber and the enzyme reaction chamber is blocked when the rubber tube plug is inserted, and is connected when the sample nucleic acid is released and the sample loading module is inserted;

[0010] The chamber is pre-filled with diluent, and when the sample nucleic acid is released and the sample adding module is inserted, the diluent can enter the enzyme reaction chamber along the connecting pipe under the push of the injection piston to dilute the enzyme reaction solution.

[0011] Furthermore, the test strip lateral flow chromatography chamber is formed by vertically inserting a test strip card into the enzyme reaction and test strip detection component body to form a closed chamber, and the test strip card is formed by clamping a test strip lower base plate, a test strip and an upper cover plate with a transparent observation window. The test strip lateral flow chromatography chamber is connected to the enzyme reaction chamber through a pipeline. After the enzyme reaction solution is diluted by the diluent and enters the test strip lateral flow chromatography chamber, it combines with the test strip sample binding pad to complete lateral flow chromatography and strip display on the test strip.

[0012] Furthermore, the sample nucleic acid release and loading module includes a tube body with openings at both ends, an extrudable and deformable rubber piece fixedly mounted on one end of the tube body, and an end cap detachably threadedly mounted on the other end of the tube body, and a liquid outlet mechanism is fixedly mounted on the end cap.

[0013] Furthermore, it also includes a constant temperature amplification incubation mixing component, which is used to provide a constant temperature incubation temperature for the enzyme reaction and the test strip detection component and magnetically stir the enzyme reaction solution. The constant temperature amplification incubation mixing component includes:

[0014] A semiconductor constant temperature heating plate, which forms a preset constant incubation temperature of 37-65°C when powered on;

[0015] A mixing device is arranged directly below the semiconductor constant temperature heating plate, comprising a magnetic plate holder with a magnetic plate installed thereon and a micro motor, which forms a rotating magnetic field when powered on, and the rotating magnetic field drives the magnetic stirrer in the enzyme reaction chamber to rotate; and,

[0016] The push rod is arranged directly below the diluent injection chamber and is configured such that the push rod is installed on an eccentric wheel. The eccentric wheel is driven by a motor. When the incubation time of the constant temperature amplification incubation mixing component is completed, the motor drives the eccentric wheel to rotate and drive the push rod to move upward. The push rod can drive the piston of the diluent injection chamber to push the diluent into the enzyme reaction chamber.

[0017] Furthermore, it also includes a diaphragm sleeve, which is embedded in the groove of the lower bottom plate of the test strip, and one end of the diaphragm sleeve is open, and the diaphragm sleeve has a strip opening, and the strip opening is closed by flipping a floating membrane, the size of the strip opening is larger than the size of the test strip, the edge of the floating membrane is overlapped with the diaphragm sleeve, and the floating membrane gradually adheres to the diaphragm sleeve as the upper cover plate is pushed up.

[0018] Furthermore, a storage compartment for accommodating a replacement diaphragm sleeve is provided on the lower bottom plate of the test strip, and a cotton roller is provided at the end of the storage compartment. The cotton roller is wet, and when the diaphragm sleeve is pulled downward from the storage compartment, it passes through the cotton roller so that moisture adheres to the outer surface and is attached and positioned in the groove entering the lower bottom plate of the test strip, wherein the end of the diaphragm sleeve has a pulling portion.

[0019] Furthermore, the opening end of the diaphragm sleeve is wide inside and narrow outside, and the height of the outlet end of the accommodating chamber is lower than the height of the end of the groove of the lower bottom plate of the test strip.

[0020] A multi-target nucleic acid detection method based on a constant temperature expansion test strip, using the multi-target nucleic acid detection device as described above, specifically includes the following steps:

[0021] Power on the constant temperature amplification incubation mixing component to preheat the semiconductor constant temperature heating plate;

[0022] Remove the rubber tube plug of the enzyme reaction chamber of the enzyme reaction and test strip detection assembly, drop the freeze-dried ball of the reaction reagent system into the enzyme reaction chamber together with the magnetic stirrer, add the reaction solution containing the starter, insert the sample nucleic acid release and sample loading module above the enzyme reaction chamber, squeeze the rubber part of the sample nucleic acid release and sample loading module to the bottom and add the sample to be tested;

[0023] The enzyme reaction and test strip detection components added with the sample are clamped along the raised semiconductor constant temperature heating plate on the upper part of the constant temperature amplification incubation mixing component;

[0024] Press the switch of the constant temperature amplification incubation mixing component, the temperature and time countdown starts to display, the mixing device starts to operate, and the magnetic stirrer rotates in the enzyme reaction chamber under the action of the rotating magnetic field to fully mix the reagents;

[0025] After the constant temperature amplification is completed, the push rod in the constant temperature amplification incubation mixing component is driven by the internal motor to push the injection piston of the diluent injection chamber, and the diluent enters the enzyme reaction chamber along the channel under the push of the injection piston to dilute the enzyme reaction product, and continues to enter the lateral flow chromatography chamber along the channel;

[0026] The diluted enzyme reaction product is combined with the test strip sample binding pad in the lateral flow chromatography chamber, and the lateral flow chromatography is started. After standing for a period of time, the test result is observed through the transparent observation window, and the positive or negative test is determined according to the strip of the test strip.

[0027] The beneficial effects of the present invention are embodied in:

[0028] In the present invention, multiple nucleic acid targets can be detected simultaneously, and by integrating the enzyme reaction and test strip detection components with the constant temperature amplification incubation components, the entire detection process is made simpler to operate and more convenient to use, which is conducive to the rapid detection technology entering the home to realize self-testing. At the same time, the entire enzyme reaction and lateral flow chromatography are completed in a closed environment, which can effectively prevent nucleic acid aerosol contamination. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the structure of the multi-target nucleic acid detection device of the present invention (installed with sample nucleic acid release and sample loading modules);

[0030] Figure 2This is a schematic diagram of the structure of the multi-target nucleic acid detection device of the present invention (with a rubber tube plug installed);

[0031] Figure 3 This is a schematic diagram of the structure of the lateral flow chromatography chamber of the test strip of the present invention;

[0032] Figure 4 This is a schematic diagram of the structure of the rubber pipe plug of the present invention;

[0033] Figure 5 This is a schematic diagram of the structure of the sample nucleic acid release and sample loading module of the present invention;

[0034] Figure 6 It is a schematic diagram of the structure of the diaphragm sleeve of the present invention;

[0035] Figure 7 This is a schematic diagram of the structure in which the diaphragm of the present invention is sleeved inside the lower bottom plate of the test strip;

[0036] Figure 8 It is a schematic diagram of the process of the nucleic acid detection method of the present invention.

[0037] Description of reference numerals:

[0038] 100, enzyme reaction chamber; 101, magnetic stirrer; 102, freeze-dried ball storage hole; 103, sample nucleic acid release and loading module; 104, rubber tube plug; 200, diluent injection chamber; 201, cylindrical sleeve; 202, injection piston; 300, test strip lateral flow chromatography chamber; 301, test strip lower bottom plate; 302, test strip; 303, upper cover plate; 304, test strip card; 305, diaphragm sleeve; 306, floating membrane; 307, containing chamber; 308, cotton roller; 400, constant temperature amplification incubation mixing component; 401, semiconductor constant temperature heating plate; 402, mixing device; 403, ejector rod; 404, eccentric wheel. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. In the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0040] See also Figure 1-5 The present invention provides a multi-target nucleic acid detection device based on a constant temperature expansion test strip, comprising:

[0041] The enzyme reaction and test strip detection component is configured to form a sealed chamber in which liquid can flow, and the formed sealed chamber includes an enzyme reaction chamber 100, a diluent injection chamber 200 and a test strip lateral flow chromatography chamber 300. The enzyme reaction chamber 100, the diluent injection chamber 200 and the test strip lateral flow chromatography chamber 300 realize constant temperature amplification enzyme reaction, enzyme reaction product dilution and lateral flow chromatography through a liquid channel.

[0042] In the present invention, multiple nucleic acid targets can be detected simultaneously, and by integrating the enzyme reaction and test strip detection components with the constant temperature amplification incubation components, the entire detection process is made simpler to operate and more convenient to use, which is conducive to the rapid detection technology entering the home to realize self-testing. At the same time, the entire enzyme reaction and lateral flow chromatography are completed in a closed environment, which can effectively prevent nucleic acid aerosol contamination.

[0043] In one embodiment, a magnetic stirrer 101 is preset in the enzyme reaction chamber 100, and a freeze-dried ball storage hole 102 for pre-setting freeze-dried balls for enzyme reaction is provided on the upper part of the enzyme reaction chamber 100. The freeze-dried ball storage hole 102 is connected to the enzyme reaction chamber 100 through an inclined channel, and the freeze-dried ball storage hole 102 is separated from the enzyme reaction chamber 100 by a rubber tube plug 104. A sample nucleic acid release and loading module 103 is provided on the upper part of the enzyme reaction chamber 100, and after the sample nucleic acid release and loading module 103 is inserted, a sealed space is formed with the enzyme reaction chamber 100.

[0044] In one embodiment, the diluent injection chamber 200 is formed into a chamber by a cylindrical sleeve 201 and an injection piston 202, and the upper part of the chamber is connected to the enzyme reaction chamber 100 through a pipeline. The connection between the chamber and the enzyme reaction chamber 100 is blocked when the rubber tube plug 104 is inserted, and is connected when the sample nucleic acid release and loading module 103 is inserted;

[0045] The chamber is pre-filled with diluent, and when the sample nucleic acid is released and the sample adding module 103 is inserted, the diluent can enter the enzyme reaction chamber 100 along the connecting pipe under the push of the injection piston 202 to dilute the enzyme reaction solution.

[0046] In one embodiment, the test strip lateral flow chromatography chamber 300 is formed by vertically inserting the test strip card 304 into the enzyme reaction and test strip detection component body to form a closed chamber. The test strip card 304 is formed by clamping the test strip lower base plate 301, the test strip 302 and the upper cover plate 303 with a transparent observation window. The test strip lateral flow chromatography chamber 300 is connected to the enzyme reaction chamber 100 through a pipeline. After the enzyme reaction solution is diluted by the diluent and enters the test strip lateral flow chromatography chamber 300, it combines with the sample binding pad of the test strip 302 to complete the lateral flow chromatography and strip display on the test strip 302.

[0047] In one embodiment, the sample nucleic acid release and loading module 103 includes a tube body with openings at both ends, a rubber member that can be squeezed and deformed and fixedly installed at one end of the tube body, and an end cap that is detachably threadedly installed at the other end of the tube body, and a liquid outlet mechanism is fixedly installed on the end cap.

[0048] In one embodiment, a constant temperature amplification incubation mixing component 400 is also included, which is used to provide a constant temperature incubation temperature for the enzyme reaction and the test strip detection component and magnetically stir the enzyme reaction solution. The constant temperature amplification incubation mixing component 400 includes:

[0049] The semiconductor constant temperature heating plate 401 forms a preset constant incubation temperature of 37-65° C. when powered on;

[0050] The mixing device 402 is arranged directly below the semiconductor constant temperature heating plate 401, and includes a magnetic plate holder with a magnetic plate installed thereon and a micro motor. When powered on, a rotating magnetic field is formed, and the rotating magnetic field drives the magnetic stirrer 101 in the enzyme reaction chamber 100 to rotate; and,

[0051] The push rod 403 is arranged directly below the diluent injection chamber 200 and is configured such that the push rod 403 is installed on the eccentric wheel 404. The eccentric wheel 404 is driven by a motor. When the incubation time of the constant temperature amplification incubation mixing component 400 is completed, the motor drives the eccentric wheel 404 to rotate and drive the push rod 403 to move upward. The push rod 403 can drive the piston of the diluent injection chamber 200 to push the diluent into the enzyme reaction chamber 100.

[0052] See also Figure 6 and Figure 7 , and also includes a diaphragm sleeve 305, which is embedded in the groove of the lower bottom plate 301 of the test strip, and one end of the diaphragm sleeve 305 is open, and the diaphragm sleeve 305 has a strip-shaped opening, which is turned and closed by a floating membrane 306, and the size of the strip-shaped opening is larger than the size of the test strip 302. The edge of the floating membrane 306 is overlapped with the diaphragm sleeve 305, and the floating membrane 306 gradually adheres to the diaphragm sleeve 305 as the upper cover plate 303 is pushed up.

[0053] The present embodiment is configured as follows: before the detection begins, the test strip 302 is placed into the groove. At this time, the test strip 302 is located within the protection range of the diaphragm sleeve 305. The upper cover plate 303 is then pushed upward. During the pushing process, the floating membrane 306 is pressed against and gradually adheres to the strip-shaped opening on the diaphragm sleeve 305, and finally the strip-shaped opening is closed. The test strip 302 is protected and isolated by the diaphragm sleeve 305, so that the test strip 302 is prevented from contaminating the lower bottom plate 301 and the upper cover plate 303 of the test strip after the enzyme reactant is immersed, thereby improving the accuracy of the detection. The diaphragm sleeve 305 is a disposable item, which can be used once and replaced once, which is simple and convenient.

[0054] The lower bottom plate 301 of the test strip is provided with a storage chamber 307 for accommodating a replacement diaphragm sleeve 305, and a cotton roller 308 is provided at the end of the storage chamber 307. The cotton roller 308 is moist, and when the diaphragm sleeve 305 is pulled downward from the storage chamber 307, it passes through the cotton roller 308 so that moisture adheres to the outer surface, and is attached and positioned in the groove of the lower bottom plate 301 of the test strip, wherein the end of the diaphragm sleeve 305 has a pulling portion. The pulling portion is released outward as the diaphragm sleeve 305 is progressively replaced upward.

[0055] The present embodiment is configured in this way, and the diaphragm sleeve 305 can be prevented from being replaced by the configuration of the accommodating bin 307. The diaphragm sleeves 305 are stacked in the accommodating bin 307, and one sheet is pulled out at a time, and enters the groove of the lower bottom plate 301 of the test strip along the guide, and unfolds after leaving the accommodating bin 307, and tears the floating film 306 to a drooping state. At the same time, during the process of being pulled, the outer surface of the diaphragm sleeve 305 contacts the cotton roller 308 and adheres to moisture, so that the diaphragm sleeve 305 is more stably attached after entering the groove of the lower bottom plate 301 of the test strip.

[0056] Specifically, an elastic push piece is provided at the bottom of the accommodating chamber 307 to ensure that the diaphragm sleeve 305 accommodated is in a stressed state, so that a single diaphragm sleeve 305 can be pulled outward each time. At the same time, a guide groove is provided on the lower bottom plate 301 of the test strip through which the diaphragm sleeve 305 is pulled outward.

[0057] The opening end of the diaphragm sleeve 305 is wide inside and narrow outside, and the height of the outlet end of the accommodating chamber 307 is lower than the height of the end of the groove of the lower bottom plate 301 of the test strip.

[0058] The configuration of this embodiment can avoid the problem of the test strip 302 easily falling off after being placed in, and maintain the position stability of the test strip 302. At the same time, the height difference setting can maintain the pressure between the test strip 302 and the cotton roller 308 when the new test strip 302 is pulled into the receiving chamber 307, so that sufficient moisture is adhered to the outer surface of the test strip 302, thereby maintaining the subsequent adsorption force in the receiving chamber 307, thereby achieving the effect of maintaining the stability of the diaphragm sleeve 305.

[0059] The present invention also provides a multi-target nucleic acid detection method based on constant temperature expansion test strips, please refer to Figure 8 , using the multi-target nucleic acid detection device as described above, specifically comprising the following steps:

[0060] The constant temperature amplification incubation mixing component 400 is powered on to preheat the semiconductor constant temperature heating plate 401;

[0061] Remove the rubber tube plug 104 of the enzyme reaction chamber 100 of the enzyme reaction and test strip detection assembly, drop the freeze-dried ball of the reaction reagent system into the enzyme reaction chamber 100 and the magnetic stirrer 101, add the reaction solution containing the starter, insert the sample nucleic acid release and sample loading module 103 above the enzyme reaction chamber 100, squeeze the rubber part of the sample nucleic acid release and sample loading module 103 to the bottom and add the sample to be tested;

[0062] The enzyme reaction and test strip detection components added with the sample are clamped along the raised semiconductor constant temperature heating plate 401 on the upper part of the constant temperature amplification incubation mixing component 400;

[0063] The switch of the constant temperature amplification incubation mixing component 400 is pressed, the temperature and time countdown starts to be displayed, the mixing device 402 starts to operate, and the magnetic stirrer 101 rotates in the enzyme reaction chamber 100 under the action of the rotating magnetic field to fully mix the reagents;

[0064] After the constant temperature amplification is completed, the push rod 403 in the constant temperature amplification incubation mixing component 400 pushes the injection piston 202 of the diluent injection chamber 200 driven by the internal motor. The diluent enters the enzyme reaction chamber 100 along the channel under the push of the injection piston 202 to dilute the enzyme reaction product, and continues to enter the test strip lateral flow chromatography chamber 300 along the channel;

[0065] The diluted enzyme reaction product combines with the test strip sample binding pad in the test strip lateral flow chromatography chamber 300, and the lateral flow chromatography starts. After standing for a period of time, the test result is observed through the transparent observation window, and the positive or negative test is determined based on the strip of the test strip.

[0066] It should be noted that if the embodiments of the present invention involve directional indications such as up, down, left, right, front, back, etc., then the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture as shown in the accompanying drawings. If the specific posture changes, the directional indication will also change accordingly.

[0067] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or schemes that A and B meet at the same time. In addition, "multiple" refers to more than two. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist.

[0068] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A multi-target nucleic acid detection device based on a constant temperature expansion test strip, characterized in that: The invention comprises an enzyme reaction and test strip detection component, wherein the enzyme reaction and test strip detection component is configured to form a sealed chamber in which liquid can flow, wherein the sealed chamber comprises an enzyme reaction chamber, a diluent injection chamber and a test strip lateral flow chromatography chamber, wherein the enzyme reaction chamber, the diluent injection chamber and the test strip lateral flow chromatography chamber realize isothermal amplification enzyme reaction, enzyme reaction product dilution and lateral flow chromatography through a liquid channel; the test strip lateral flow chromatography chamber is formed by vertically inserting a test strip card into the enzyme reaction and test strip detection component body to form a sealed chamber, wherein the test strip card is composed of a test strip lower base plate, a test strip and an upper cover plate card with a transparent observation window. The test strip lateral flow chromatography chamber is tightly formed, and the enzyme reaction chamber is connected with the test strip lateral flow chromatography chamber through a pipeline. After the enzyme reaction liquid is diluted by the diluent and enters the test strip lateral flow chromatography chamber, it combines with the test strip sample binding pad to complete the lateral flow chromatography and strip display on the test strip; it also includes a diaphragm sleeve, which is embedded in the groove of the lower bottom plate of the test strip, and one end of the diaphragm sleeve is open. The diaphragm sleeve has a strip-shaped opening, and the strip opening is closed by flipping a floating membrane. The size of the strip opening is larger than the size of the test strip. The edge of the floating membrane is overlapped with the diaphragm sleeve, and the floating membrane gradually adheres to the upper cover plate as it is pushed up. on the diaphragm sleeve; before the test begins, the test strip is placed in the groove and is within the protection range of the diaphragm sleeve. During the upward push, the upper cover plate can press against the floating film and gradually adhere to the strip-shaped opening on the diaphragm sleeve, and finally close the strip-shaped opening, and the test strip is protected and isolated by the diaphragm sleeve; a storage bin for accommodating replacement diaphragm sleeves is provided on the lower bottom plate of the test strip, and the diaphragm sleeves are stacked in the storage bin, and a cotton roller is provided at the end of the storage bin, and the cotton roller is wet, and a pull-out portion is provided at the end of the diaphragm sleeve, and the pull-out portion can be released outward as the diaphragm sleeve is progressively replaced upward; a guide groove is provided on the lower bottom plate of the test strip, and the storage bin is provided with a guide groove, and the guide groove is provided on the lower bottom plate of the test strip. An elastic pushing piece is provided at the bottom of the storage bin, and the elastic pushing piece is used to ensure that the diaphragm sleeve accommodated in the storage bin is in a stressed state so that a single diaphragm sleeve can be pulled outward each time, and the pulled diaphragm sleeve enters the groove of the lower bottom plate of the test strip along the guide groove and unfolds after leaving the storage bin, tearing the floating film to a drooping state, and at the same time, when the diaphragm sleeve is pulled downward from the storage bin, its outer surface contacts the cotton roller and adheres to moisture, and is attached and positioned in the groove of the lower bottom plate of the test strip; the opening end of the diaphragm sleeve is wide inside and narrow outside, and the height of the outlet end of the storage bin is lower than the height of the end of the groove of the lower bottom plate of the test strip.

2. The multi-target nucleic acid detection device based on constant temperature expansion test strips as claimed in claim 1, characterized in that: A magnetic stirrer is preset in the enzyme reaction chamber, a freeze-dried ball storage hole for pre-setting freeze-dried enzyme reaction balls is arranged on the upper part of the enzyme reaction chamber, the freeze-dried ball storage hole is connected to the enzyme reaction chamber through an oblique channel, and the freeze-dried ball storage hole and the enzyme reaction chamber are separated by a rubber tube plug, a sample nucleic acid release and loading module is arranged on the upper part of the enzyme reaction chamber, and the sample nucleic acid release and loading module forms a sealed space with the enzyme reaction chamber after being inserted.

3. The multi-target nucleic acid detection device based on constant temperature expansion test strips as claimed in claim 2, characterized in that: The diluent injection chamber is formed into a chamber by a cylindrical sleeve and an injection piston, the upper part of the chamber is connected to the enzyme reaction chamber through a pipeline, the connection between the chamber and the enzyme reaction chamber is blocked when the rubber tube plug is inserted, and is connected when the sample nucleic acid is released and the loading module is inserted; the chamber is pre-filled with diluent, and when the sample nucleic acid is released and the loading module is inserted, the diluent can enter the enzyme reaction chamber along the connecting pipeline under the push of the injection piston to dilute the enzyme reaction liquid.

4. The multi-target nucleic acid detection device based on constant temperature expansion test strips as claimed in claim 2, characterized in that: The sample nucleic acid release and loading module comprises a tube body with openings at both ends, a rubber piece that can be squeezed and deformed and fixedly mounted on one end of the tube body, and an end cap that is detachably threadedly mounted on the other end of the tube body, and a liquid outlet mechanism is fixedly mounted on the end cap.

5. The multi-target nucleic acid detection device based on constant temperature expansion test strips as claimed in claim 4, characterized in that: It also includes a constant temperature amplification incubation mixing component, which is used to provide a constant temperature incubation temperature for the enzyme reaction and the test strip detection component and magnetically stir the enzyme reaction solution. The constant temperature amplification incubation mixing component includes: Semiconductor constant temperature heating plate, which forms a preset constant incubation temperature of 37-65°C when powered on; A mixing device is arranged directly below the semiconductor constant temperature heating plate, comprising a magnetic plate holder with a magnetic plate installed thereon and a micro motor, which forms a rotating magnetic field when powered on, and the rotating magnetic field drives the magnetic stirrer in the enzyme reaction chamber to rotate; and, A push rod is arranged directly below the diluent injection chamber and is configured such that the push rod is installed on an eccentric wheel, and the eccentric wheel is driven by a motor. When the incubation time of the constant temperature amplification incubation mixing component is completed, the motor drives the eccentric wheel to rotate and drive the push rod to move upward. The push rod can drive the piston of the diluent injection chamber (200) to push the diluent into the enzyme reaction chamber.

6. A multi-target nucleic acid detection method based on a constant temperature expansion test strip, the method is applied for non-diagnostic purposes, the method uses the multi-target nucleic acid detection device as claimed in claim 5, characterized in that: The following steps are involved: Power on the constant temperature amplification incubation mixing component to preheat the semiconductor constant temperature heating plate; Remove the rubber tube plug of the enzyme reaction chamber of the enzyme reaction and test strip detection assembly, drop the freeze-dried ball of the reaction reagent system into the enzyme reaction chamber together with the magnetic stirrer, add the reaction solution containing the starter, insert the sample nucleic acid release and sample loading module above the enzyme reaction chamber, squeeze the rubber part of the sample nucleic acid release and sample loading module to the bottom to add the sample to be tested; The enzyme reaction and test strip detection components of the added sample are clamped along the raised semiconductor constant temperature heating plate on the upper part of the constant temperature amplification incubation mixing component; Press the switch of the constant temperature amplification incubation mixing component, the temperature and time countdown starts to display, the mixing device starts to operate, and the magnetic stirrer rotates in the enzyme reaction chamber under the action of the rotating magnetic field to fully mix the reagents; After the constant temperature amplification is completed, the push rod in the constant temperature amplification incubation mixing component is driven by the internal motor to push the injection piston of the diluent injection chamber. The diluent enters the enzyme reaction chamber along the channel under the push of the injection piston to dilute the enzyme reaction product, and continues to enter the test strip lateral flow chromatography chamber along the channel; The diluted enzyme reaction product combines with the sample binding pad of the test strip in the lateral flow chromatography chamber of the test strip, and the lateral flow chromatography begins. After standing for a period of time, the test results are observed through the transparent observation window, and the positive or negative test is determined based on the strips on the test strip.

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