Gene detection instrument and detection method

Abstract

The invention discloses a gene detector and a detection method, belonging to the technical field of gene detection, comprising a detector body, a detection box, a temperature feedback mechanism and a slave adjustment mechanism. The invention designs corresponding temperature feedback mechanisms and slave adjustment mechanisms around denaturation, annealing and extension steps in a PCR thermal cycle process, and performs adaptive adjustment and deformation of the device according to the temperature interval corresponding to each step, thereby ensuring that during the denaturation and annealing steps, the hot cover and the pressure pad seal the PCR reaction tube to prevent non-specific amplification, and the device is in a closed state to ensure that heat will not be lost due to external factors, and during the annealing step, good pressure relief can be performed, and the inside of the device quickly dissipates heat to a suitable working temperature range, preventing data errors caused by interference from external factors, thereby effectively improving the accuracy of the device detection and analysis results.

Description

Technical Field

[0001] The present invention relates to the technical field of gene detection, and more specifically, to a gene detection instrument and a detection method. Background Art

[0002] A gene is a functional fragment on a DNA molecule, the basic unit of genetic information, and the most basic factor that determines all biological species. Genetic testing identifies gene mutations associated with specific diseases or traits by detecting mutations in DNA sequences. During the testing process, it is usually necessary to extract DNA from the sample to be tested, and then use polymerase chain reaction or other technologies to amplify specific DNA fragments.

[0003] In the polymerase chain reaction (PCR reaction for short), this technology can amplify extremely small amounts of target nucleic acid fragments to 100,000 or even a million times in a short period of time, and amplify sufficient nucleic acid fragments from extremely small amounts of specimens for analysis, research, detection and identification. The sample (i.e., the solution containing the target DNA fragment) will undergo a series of temperature changes to complete the three basic reaction steps of DNA denaturation, primer annealing, and DNA polymerase extension. Among them, denaturation: heating the sample to the first target temperature range to dissociate the double-stranded DNA into single-stranded DNA, which is the first step of the PCR cycle; annealing: rapidly lowering the temperature to the second target temperature range to allow the primer (artificially synthesized short-chain DNA) to specifically bind to the single-stranded DNA of the template DNA. Primers are short-chain DNAs that are complementary to both ends of the target DNA sequence, and they provide a starting point for DNA polymerase; extension: under the action of DNA polymerase, starting with the primer and using four deoxyribonucleoside triphosphates (dNTPs) as raw materials, a new DNA chain is synthesized in the third target temperature range. This process is a key step in DNA replication. These three steps constitute a PCR cycle, which usually requires 20-40 cycles to obtain a large number of target DNA fragments in a short period of time. Therefore, PCR gene testing is essentially a process of repeated heating and cooling of the sample.

[0004] In the prior art, in order to prevent evaporation of PCR test tubes during thermal cycling, a hot cover is generally added to the top of the test tube. The hot cover is set at a temperature higher than the temperature of the reaction solution to prevent steam from condensing on the tube wall, thereby reducing evaporation. However, this also creates another problem. The hot cover usually starts to heat up and pressurize before the PCR reaction, and during the PCR reaction, the hot cover will continue to pressurize and keep warm. The top of the test tube will always be in a high temperature state due to heat conduction, which may lead to non-specificity of the PCR reaction, cause errors in subsequent analysis, and even produce completely deviated detection and analysis results, affecting the accuracy of the detection.

[0005] Therefore, in view of the above technical problems, it is necessary to provide a gene detection instrument and detection method. Summary of the invention

[0006] The object of the present invention is to provide a gene detection instrument and a detection method to solve the above-mentioned problems.

[0007] In order to achieve the above purpose, the technical solution provided by an embodiment of the present invention is as follows:

[0008] A gene detector, a detector body and a detection box, wherein the detection box is arranged on the detector body, the detection box is composed of a hinged upper cover and a box body, the box body is fixedly connected to a sample box through a positioning rod, a PCR reaction tube is inserted in a sample hole on the sample box, air outlets are provided on both sides of the detection box, a temperature control system is arranged in the detector body, and the temperature control system is used to control the temperature around the three reaction steps of denaturation, annealing and extension during the PCR thermal cycle; the temperature feedback mechanism includes an isolation plate, the isolation plate is arranged in a first slide groove provided inside the box body, and ... The lower end of the isolation plate is fixedly connected with a heat cover whose number and position correspond to the PCR reaction tubes, the isolation plate is fixedly connected with heat drive rods at the four corners of the inner top of the box body, and the lower end of the isolation plate is fixedly connected with a pair of symmetrically distributed extension plates; the driven adjustment mechanism includes a pair of special-shaped plates, the special-shaped plates are arranged in the second slide groove opened inside the upper cover, and the special-shaped plates are fixedly connected with the inner bottom end of the second slide groove. A micro-compression spring is fixedly connected, and the left and right ends of the sample box are fixedly connected with a pair of connecting plates, and the interior of the connecting plates is fixedly connected with a magnetic shielding film, and the magnetic shielding film is located between the extension plate and the special-shaped plate;

[0009] In the three reaction steps of denaturation, annealing and extension, the temperature control system has a denaturation temperature of 90-95°C and a duration of 35-45 seconds, an annealing temperature of 50-55°C and a duration consistent with the denaturation temperature duration, and an extension temperature of 70-75°C, and the duration depends on the length of the DNA fragment to be amplified and the activity of the enzyme;

[0010] The thermal drive rod is made of a shape memory alloy, which is a shape memory alloy with a two-way memory effect and is in a low-temperature phase at 50° and in a high-temperature phase at 70-90°;

[0011] A first magnetic block is embedded in the inner end of the extension plate, a second magnetic block is embedded in the inner end of the special-shaped plate, and the first magnetic block is located directly above the second magnetic block.

[0012] As a further improvement of the present invention, during the three reaction steps of denaturation, annealing and extension, the temperature control system has a denaturation temperature of 90-95°C and a duration of 35-45 seconds, an annealing temperature of 50-55°C and a duration consistent with the denaturation temperature duration, and an extension temperature of 70-75°C, and the duration depends on the length of the DNA fragment to be amplified and the activity of the enzyme.

[0013] As a further improvement of the present invention, the thermal drive rod is made of a shape memory alloy, which is a shape memory alloy with a two-way memory effect and is in a low-temperature phase at 50° and in a high-temperature phase at 70-90°.

[0014] As a further improvement of the present invention, the isolation plate is made of a thermal insulation material, and a plurality of overflow holes are provided on the surface of the isolation plate.

[0015] As a further improvement of the present invention, a pressure pad is fixedly connected to the lower end of the thermal cover, and the pressure pad is a liquid pressure pad filled with DBE liquid.

[0016] As a further improvement of the present invention, the pressure pad is configured to be in a truncated cone shape, and the diameter of the pressure pad at one end close to the PCR reaction tube is smaller than the diameter at one end close to the heat cover.

[0017] As a further improvement of the present invention, one end of the special-shaped plate outside the second slide groove is almost in contact with the inner wall of the box body, and the top of the special-shaped plate is flush with the lowest opening of the air outlet.

[0018] As a further improvement of the present invention, the magnetic shielding membrane includes a magnetic shielding half membrane, an elastic expansion hole, and magnetic shielding petals. The magnetic shielding half membrane is made of high-temperature resistant elastic material. An elastic expansion hole is opened at the center of the magnetic shielding half membrane, and the elastic expansion hole is located directly below the extension plate. A pair of magnetic shielding petals are fixedly connected to the inner bottom of the magnetic shielding half membrane, and the pair of magnetic shielding petals are distributed on both sides of the elastic expansion hole.

[0019] As a further improvement of the present invention, a detection method of a gene detector, using the gene detector, comprises the following steps:

[0020] S1. Reagent preparation: Add the following reagents into the PCR reaction tube: DNA fragments extracted from biological samples, primers, DNA polymerase, buffer and deoxyribonucleoside triphosphates. Mix well and then place the PCR reaction tube into the sample well on the sample box.

[0021] S2. Denaturation reaction: The temperature control system controls the temperature in the detection box to quickly reach 90-95°C, so that the double-stranded DNA template in the PCR reaction tube is denatured to form two single-stranded DNAs. The heat drive rod is in a high-temperature phase in this temperature range, pushing the isolation plate and the heat cover downward, pushing the heat cover to a position flush with the tube mouth of the PCR reaction tube, so that the pressure pad fills the opening of the PCR reaction tube. In this state, the extension plate penetrates the elastic expansion hole, the special-shaped plate moves upward to fit the extension plate, and the air outlet is blocked;

[0022] S3, annealing reaction: the temperature control system controls the temperature in the detection box to drop back to 50-55°C, so that the two oligonucleotide primers are complementary to the two single strands on both sides of the target gene, forming a primer-template complex. The heat drive rod is in a low-temperature phase in this temperature range, pulling the isolation plate and the heat cover upward, and there is a partial gap between the pressure pad and the tube mouth of the PCR reaction test tube. In this state, the extension plate is located above the magnetic shielding film, and the special-shaped plate is pulled back to its original position by the micro-compression spring, and its top is flush with the lowest opening of the air outlet;

[0023] S4, extension reaction: The heat-resistant DNA polymerase begins to incorporate single nucleotides from the 3' end of the primer using the target gene as a template, extending along the 5'→3' direction to synthesize a new DNA complementary chain. In this reaction, the movement state of the components in the temperature feedback mechanism and the driven regulation mechanism is the same as that in the denaturation reaction;

[0024] S5. Cycling and product analysis: The denaturation, annealing and extension steps are repeated 20 to 40 times until the PCR reaction is completed, and the PCR product is stored at 4°C or removed for subsequent analysis.

[0025] Compared with the prior art, the advantages of the present invention are:

[0026] This solution designs corresponding temperature feedback mechanisms and slave adjustment mechanisms around the denaturation, annealing and extension steps during the PRC thermal cycle process. The equipment is adaptively adjusted and deformed according to the temperature range corresponding to each step, thereby ensuring that the hot cover and the pressure pad seal the PCR reaction tube during the denaturation and annealing steps to prevent non-specific amplification, and the equipment is in a closed state to ensure that heat will not be lost due to external factors. During the annealing step, good pressure relief can be performed, and the heat inside the equipment is quickly dissipated to a suitable working temperature range to prevent data errors caused by interference from external factors, thereby effectively improving the accuracy of the equipment's detection and analysis results. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the three-dimensional structure of the main body of the detector of the present invention;

[0028] Figure 2 It is a front cross-sectional view inside the detection chamber of the present invention;

[0029] Figure 3 For the present invention Figure 2 Another state diagram of ;

[0030] Figure 4 For the present invention Figure 2 A in the enlarged view;

[0031] Figure 5 For the present invention Figure 3 The enlarged view of point B in the figure;

[0032] Figure 6 It is a schematic structural diagram of the magnetic shielding film of the present invention;

[0033] Figure 7 The figure is a flow chart of the method of the present invention.

[0034] Description of the numbers in the figure:

[0035] 1 detector body, 2 detection box, 201 upper cover, 202 box body, 203 air outlet, 204 first slide slot, 205 second slide slot, 3 sample box, 4 PCR reaction tube, 5 isolation plate, 501 overflow hole, 6 thermal cover, 601 pressure pad, 7 thermal drive rod, 8 extension plate, 801 magnetic block one, 9 special-shaped plate, 901 magnetic block two, 10 micro compression spring, 11 connecting plate, 12 magnetic shielding film, 1201 magnetic shielding half film, 1202 elastic expansion hole, 1203 magnetic shielding flap. DETAILED DESCRIPTION

[0036] 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; it is obvious that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments, and all other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making creative work are within the scope of protection of the present invention. Example

[0037] See also Figure 1-7A gene detector and a detection method, a detector body 1 and a detection box 2, the detection box 2 is arranged on the detector body 1, the detection box 2 is composed of a hinged upper cover 201 and a box body 202, the box body 202 is fixedly connected with a sample box 3 through a positioning rod, a PCR reaction tube 4 is inserted in the sample hole on the sample box 3, and an air outlet 203 is opened on the left and right sides of the detection box 2. A temperature control system is arranged in the detector body 1, and the temperature control system is used to control the temperature around the three reaction steps of denaturation, annealing and extension during the PCR thermal cycle. During the three reaction steps of denaturation, annealing and extension, the temperature of the temperature control system is 90-95°C, the duration is 35-45 seconds, the annealing temperature is 50-55°C, the duration is consistent with the denaturation temperature duration, and the extension temperature is 70-75°C, and the duration depends on the length of the DNA fragment to be amplified and the activity of the enzyme.

[0038] The temperature feedback mechanism includes an isolation plate 5, which is arranged in a first slide groove 204 opened in the box body 202. The lower end of the isolation plate 5 is fixedly connected to a heat cover 6 whose number and position correspond to the PCR reaction tube 4. The lower end of the heat cover 6 is fixedly connected to a pressure pad 601, which is a liquid pressure pad filled with DBE liquid. The pressure pad 601 is set to a truncated cone shape, and the diameter of the end of the pressure pad 601 close to the PCR reaction tube 4 is smaller than the diameter of the end close to the heat cover 6. During the denaturation reaction, the heat cover 6 fits the PCR reaction tube 4, and the pressure pad 601 is completely located in the PCR reaction tube 4, so as to reduce non-specific amplification. During the annealing reaction, the heat cover 6, the pressure pad 601 and the tube mouth of the PCR reaction tube 4 are not in contact with each other. There is a partial gap between the isolation plate 5 and the four corners of the inner top of the box body 202, which is used for pressure relief. The heat-driving rod 7 is fixedly connected between the isolation plate 5 and the box body 202. The heat-driving rod 7 is made of shape memory alloy. The heat-driving rod 7 is a shape memory alloy with a two-way memory effect, and is in a low-temperature phase at 50° and a high-temperature phase at 70-90°, which corresponds to the temperature range of the equipment during the three reaction steps of denaturation, annealing and extension. The isolation plate 5 is made of a heat-insulating material, and a plurality of overflow holes 501 are opened on the surface of the isolation plate 5. The overflow holes 501 are used to quickly conduct the internal heat of the detection box 2 to the position where the heat-driving rod 7 is located, so that it undergoes corresponding deformation. The lower end of the isolation plate 5 is fixedly connected with a pair of symmetrically distributed extension plates 8.

[0039] The driven adjustment mechanism includes a pair of special-shaped plates 9, which are arranged in a second slide groove 205 opened inside the upper cover 201. A micro compression spring 10 is fixedly connected between the special-shaped plate 9 and the inner bottom end of the second slide groove 205. A pair of connecting plates 11 are fixedly connected to the left and right ends of the sample box 3. A magnetic shielding film 12 is fixedly connected inside the connecting plate 11. The magnetic shielding film 12 is located between the extension plate 8 and the special-shaped plate 9. A magnetic block 1 801 is embedded in the inner end of the extension plate 8. A magnetic block 2 901 is embedded in the inner end of the special-shaped plate 9, and the magnetic block 1 801 is located directly above the magnetic block 2 901. The magnetic shielding film 12 includes a magnetic shielding half film 1201, an elastic expansion hole 1202, and a magnetic shielding flap 1203. The magnetic shielding half film 1201 is made of high-temperature resistant elastic material, and an elastic expansion hole is opened at the center of the magnetic shielding half film 1201 1202, and the elastic expansion hole 1202 is located at the lower side of the extension plate 8, the inner bottom of the magnetic shielding half membrane 1201 is fixedly connected with a pair of magnetic shielding flaps 1203, and the pair of magnetic shielding flaps 1203 are distributed on both sides of the elastic expansion hole 1202, and the magnetic shielding flaps 1203 are used to separate the magnetic force between the magnetic block 1 801 and the magnetic block 2 901. When the elastic expansion hole 1202 is subjected to the downward impact force of the extension plate 8, the magnetic shielding half membrane 1201 can be separated to both sides. After the extension plate 8 is reset, the magnetic shielding half membrane 1201 is reset again through elasticity, and the magnetic force between the magnetic block 1 801 and the magnetic block 2 901 is again separated. The end of the special-shaped plate 9 located outside the second slide groove 205 is almost in contact with the inner wall of the box body 202, and the top of the special-shaped plate 9 is flush with the lowest opening of the air outlet 203. When the denaturation reaction occurs, please refer to Figure 2 and Figure 4 , the temperature range in the equipment is 90-95°C, the heat drive rod 7 is in the high temperature phase, its length is extended, pushing the isolation plate 5 to move to the bottom of the first slide groove 204, and the isolation plate 5 drives the extension plate 8 to penetrate the elastic expansion hole 1202, the magnetic block 2 901 and the magnetic block 1 801 drive the special-shaped plate 9 to move toward one end of the extension plate 8 through the magnetic reaction until the two are attached, at this time the special-shaped plate 9 blocks the outlet 203, during the annealing reaction, please refer to Figure 3 and Figure 5 , the temperature range in the equipment is between 50 and 55°C, the heat-driven rod 7 is in the low-temperature phase, and its length changes again, pulling the isolation plate 5 upward, so that the extension plate 8 moves to the top of the magnetic shielding film 12, and the magnetic shielding petal 1203 shields the magnetic force between the magnetic block 1 801 and the magnetic block 2 901.

[0040] A detection method of a gene detection instrument comprises the following steps:

[0041] S1. Reagent preparation: Add the following reagents into the PCR reaction tube 4: DNA fragments extracted from biological samples, primers, DNA polymerase, buffer and deoxyribonucleoside triphosphates. After fully mixing, place the PCR reaction tube 4 into the sample well on the sample box 3;

[0042] S2, denaturation reaction: the temperature control system controls the temperature in the detection box 2 to quickly reach 90-95°C, so that the double-stranded DNA template in the PCR reaction tube 4 is denatured to form two single-stranded DNAs. The heat drive rod 7 is in a high-temperature phase in this temperature range, pushing the isolation plate 5 and the heat cover 6 to move downward, pushing the heat cover 6 to a position flush with the tube mouth of the PCR reaction tube 4, so that the pressure pad 601 fills the opening of the PCR reaction tube 4, thereby preventing evaporation. In this state, the extension plate 8 penetrates the elastic expansion hole 1202, and the special-shaped plate 9 moves upward to fit the extension plate 8 and blocks the air outlet 203;

[0043] S3, annealing reaction: the temperature control system controls the temperature in the detection box 2 to drop to 50-55°C, so that the two oligonucleotide primers are respectively complementary to the two single strands on both sides of the target gene to form a primer-template complex. The heat drive rod 7 is in a low temperature phase in this temperature range, pulling the isolation plate 5 and the heat cover 6 to move upward, and there is a partial gap between the pressure pad 601 and the tube mouth of the PCR reaction tube 4. In this state, the extension plate 8 is located above the magnetic shielding film 12, and the special-shaped plate 9 is pulled back to its original position by the micro-compression spring 10, and its top is flush with the lowest opening of the air outlet 203;

[0044] S4, extension reaction: The heat-resistant DNA polymerase begins to incorporate single nucleotides from the 3' end of the primer using the target gene as a template, extending along the 5'→3' direction to synthesize a new DNA complementary chain. In this reaction, the movement state of the components in the temperature feedback mechanism and the driven regulation mechanism is the same as that in the denaturation reaction;

[0045] S5. Cycling and product analysis: The denaturation, annealing and extension steps are repeated 20 to 40 times until the PCR reaction is completed, and the PCR product is stored at 4°C or removed for subsequent analysis.

[0046] This solution designs corresponding temperature feedback mechanisms and slave adjustment mechanisms around the denaturation, annealing and extension steps during the PRC thermal cycle process, and the device performs adaptive adjustment and deformation according to the temperature range corresponding to each step, thereby ensuring that during the denaturation and annealing steps, the hot cover 6 and the pressure pad 601 seal the PCR reaction tube 4 to prevent non-specific amplification, and the device is in a closed state to ensure that heat will not be lost due to external factors. During the annealing step, good pressure relief can be performed, and the inside of the device quickly dissipates heat to a suitable working temperature range to prevent data errors caused by interference from external factors, thereby effectively improving the accuracy of the device's detection and analysis results.

[0047] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0048] In addition, it should be understood that although the present specification is described according to embodiments, not every embodiment contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation methods that those skilled in the art can understand.

Claims

1. A gene detection instrument, characterized in that: include: A detector body (1) and a detection box (2), wherein the detection box (2) is arranged on the detector body (1), and the detection box (2) is composed of a hinged upper cover (201) and a box body (202), wherein the box body (202) is fixedly connected to a sample box (3) via a positioning rod, a PCR reaction tube (4) is inserted into a sample hole on the sample box (3), and air outlets (203) are provided on both left and right sides of the detection box (2), and a temperature control system is arranged in the detector body (1), and the temperature control system is used to control the temperature around the three reaction steps of denaturation, annealing and extension during the PCR thermal cycle process; The temperature feedback mechanism comprises an isolation plate (5), the isolation plate (5) being arranged in a first slide groove (204) provided inside the box body (202), the lower end of the isolation plate (5) being fixedly connected with heat covers (6) whose number and position correspond to the number of PCR reaction tubes (4), heat drive rods (7) being fixedly connected between the isolation plate (5) and the four corners of the inner top end of the box body (202), and the lower end of the isolation plate (5) being fixedly connected with a pair of symmetrically distributed extension plates (8); The driven adjustment mechanism comprises a pair of special-shaped plates (9), wherein the special-shaped plates (9) are arranged in a second slide groove (205) opened inside the upper cover (201), and a micro-compression spring (10) is fixedly connected between the special-shaped plates (9) and the inner bottom end of the second slide groove (205), and a pair of connecting plates (11) are fixedly connected at both left and right ends of the sample box (3), and a magnetic shielding film (12) is fixedly connected inside the connecting plate (11), and the magnetic shielding film (12) is located between the extension plate (8) and the special-shaped plate (9); In the three reaction steps of denaturation, annealing and extension, the temperature control system has a denaturation temperature of 90-95°C and a duration of 35-45 seconds, an annealing temperature of 50-55°C and a duration consistent with the denaturation temperature duration, and an extension temperature of 70-75°C, and the duration depends on the length of the DNA fragment to be amplified and the activity of the enzyme; The thermal drive rod (7) is made of a shape memory alloy. The thermal drive rod (7) is a shape memory alloy with a two-way memory effect and is in a low-temperature phase at 50° and in a high-temperature phase at 70-90°; A first magnetic block (801) is embedded at the inner end of the extension plate (8), a second magnetic block (901) is embedded at the inner end of the special-shaped plate (9), and the first magnetic block (801) is located directly above the second magnetic block (901).

2. A gene detection instrument according to claim 1, characterized in that: The isolation plate (5) is made of a thermal insulation material, and a plurality of overflow holes (501) are provided on the surface of the isolation plate (5).

3. A gene detection instrument according to claim 1, characterized in that: A pressure pad (601) is fixedly connected to the lower end of the thermal cover (6), and the pressure pad (601) is a liquid pressure pad filled with DBE liquid.

4. A gene detection instrument according to claim 3, characterized in that: The pressure pad (601) is configured to be in a truncated cone shape, and the diameter of the pressure pad (601) at one end close to the PCR reaction tube (4) is smaller than the diameter of the end close to the heat cover (6).

5. A gene detection instrument according to claim 1, characterized in that: One end of the shaped plate (9) located outside the second slide groove (205) is nearly in contact with the inner wall of the box body (202), and the top of the shaped plate (9) is flush with the lowest opening of the air outlet (203).

6. A gene detection instrument according to claim 1, characterized in that: The magnetic shielding film (12) comprises a magnetic shielding half film (1201), an elastic expansion hole (1202), and magnetic shielding petals (1203); the magnetic shielding half film (1201) is made of a high-temperature resistant elastic material; an elastic expansion hole (1202) is provided at the center of the magnetic shielding half film (1201), and the elastic expansion hole (1202) is located directly below the extension plate (8); a pair of magnetic shielding petals (1203) are fixedly connected to the inner bottom of the magnetic shielding half film (1201), and the pair of magnetic shielding petals (1203) are distributed on both sides of the elastic expansion hole (1202).

7. A detection method of a gene detection instrument, characterized in that: The gene detection instrument according to any one of claims 1 to 6 comprises the following steps: S1. Reagent preparation: Add the following reagents into a PCR reaction tube (4): DNA fragments extracted from biological samples, primers, DNA polymerase, buffer and deoxyribonucleoside triphosphates, mix thoroughly and evenly, and then place the PCR reaction tube (4) into the sample well on the sample box (3); S2, denaturation reaction: the temperature control system controls the temperature in the detection box (2) to quickly reach 90-95°C, so that the double-stranded DNA template in the PCR reaction tube (4) is denatured to form two single-stranded DNAs. The heat drive rod (7) is in a high-temperature phase in this temperature range, pushing the isolation plate (5) and the heat cover (6) to move downward, pushing the heat cover (6) to a position flush with the tube mouth of the PCR reaction tube (4), so that the pressure pad (601) fills the opening of the PCR reaction tube (4). In this state, the extension plate (8) penetrates the elastic expansion hole (1202), and the special-shaped plate (9) moves upward to fit the extension plate (8) and seals the air outlet (203); S3, annealing reaction: the temperature control system controls the temperature in the detection box (2) to drop back to 50-55°C, so that the two oligonucleotide primers are respectively complementary to the two single strands on both sides of the target gene to form a primer-template complex. The heat drive rod (7) is in a low temperature phase in this temperature range, pulling the isolation plate (5) and the heat cover (6) to move upward, and there is a partial gap between the pressure pad (601) and the tube mouth of the PCR reaction test tube (4). In this state, the extension plate (8) is located above the magnetic shielding film (12), and the special-shaped plate (9) is pulled back to its original position by the micro-compression spring (10), and its top is flush with the lowest opening of the air outlet (203); S4, extension reaction: The heat-resistant DNA polymerase begins to incorporate single nucleotides from the 3' end of the primer using the target gene as a template, extending along the 5'→3' direction to synthesize a new DNA complementary chain. In this reaction, the movement state of the components in the temperature feedback mechanism and the driven regulation mechanism is the same as that in the denaturation reaction; S5. Cycling and product analysis: The denaturation, annealing and extension steps are repeated 20 to 40 times until the PCR reaction is completed, and the PCR product is stored at 4°C or removed for subsequent analysis.

Images