Meat adulteration rapid inspection device capable of preventing nucleic acid aerosol pollution

Abstract

The utility model relates to the technical field of molecular biology experimental equipment, and discloses a meat adulteration rapid inspection device capable of preventing nucleic acid aerosol pollution, which comprises a rapid inspection box shell, and a DNA (deoxyribonucleic acid) extraction chamber, a DNA amplification chamber and an adulteration analysis chamber are respectively arranged in a cavity of the rapid inspection box shell; the DNA extraction chamber is communicated with the inner cavity of the DNA amplification chamber through an inverted U-shaped polytetrafluoroethylene tube; the DNA amplification chamber is communicated with the adulteration analysis chamber through a DNA amplification liquid transfer device; a sample adding opening, an air exhaust needle cylinder connecting opening and a test paper loading opening are formed in the top of the rapid test box shell; the sample adding opening and the air exhaust needle cylinder connecting opening are both communicated with the DNA extraction chamber. According to the utility model, the closed rapid detection box is adopted, so that the aerosol formed in the DNA amplification process is prevented from diffusing and polluting other sample detection systems, external pipetting equipment is not required to participate in the whole experiment process, the whole detection environment is ensured not to be polluted by the aerosol, and the circulating pollution is avoided.

Description

Technical Field

[0001] The utility model belongs to the technical field of molecular biology experimental equipment, and in particular relates to a meat adulteration rapid detection device capable of preventing nucleic acid aerosol contamination. Background Art

[0002] Because meat undergoes various deep processing methods, its original properties and sensory properties are destroyed, making it difficult to identify with basic visual methods. Furthermore, the use of additives such as flavors and fragrances, coupled with the difficulty of implementing full traceability in the deeply processed meat industry, has led to increasingly stringent requirements for meat adulteration identification technology. While ensuring accurate and reliable identification results, these technologies must be rapid, simple, and easy to use, suitable for diverse experimental environments. PCR-based identification techniques are not suitable for integrated portable testing systems and point-of-care applications, such as supermarkets, farmers' markets, meat production facilities, and quarantine points. Rapid DNA testing is portable and easy to use. Key technical components of rapid DNA testing are DNA amplification and amplification product analysis. Rapid DNA amplification typically utilizes isothermal amplification, while rapid analysis of amplification products typically relies on visual analysis techniques. Research has demonstrated the rapid identification of some food adulterations by combining loop-mediated isothermal amplification with nucleic acid lateral flow immunoassays. Loop-mediated isothermal amplification (LAMP) is a technique for isothermal amplification of target species-specific DNA sequences. It can synthesize large quantities of target DNA fragments in a short period of time, with enhanced specificity. A reaction system containing template DNA, primers, a DNA polymerase with high strand displacement activity, and dNTPs is amplified in a single step at a constant temperature (60-66°C), producing over 50 times more copies than PCR. Lateral flow immunoassay (LFIA) is an immunochromatographic technique performed on a lateral flow test strip (LFD). It uses a strip of fiber-like chromatographic material as the solid phase. The sample is moved across the material by capillary adsorption. The analyte in the sample binds to antibodies in specific regions on the material, and intuitive test results are obtained quickly through an enzymatic colorimetric reaction or by directly using a colorimetric marker.

[0003] Although many literature and kits have developed a number of nucleic acid rapid detection methods and kits based on the aforementioned DNA rapid detection principle, such as the publication number CN212640438U, "A Meat Sample Nucleic Acid Detection Device Based on Hydroxynaphthol Blue Indicator," existing kits and nucleic acid rapid detection methods have the following drawbacks:

[0004] (1) The sampling, DNA extraction, loop-mediated isothermal amplification and lateral flow immunoassay steps are centralized batch processing. The DNA extraction, loop-mediated isothermal amplification and lateral flow immunoassay steps require manual assistance for connection, such as using a pipette to transfer liquids and add liquids, which is very easy to cause cross-contamination between samples. Due to the extremely high amplification efficiency of loop-mediated isothermal amplification for target DNA, even with only a trace amount of DNA template, a large number of copies can be obtained in a short time. The detection sensitivity of the method is very high. Even if there is a trace amount of cross-contamination of the target meat during the process, the result will show positive. The centralized batch processing of samples may lead to the misjudgment of adulteration results.

[0005] (2) DNA extraction, loop-mediated isothermal amplification, and lateral flow immunoassay are all processed in an open environment. After DNA is extracted and amplified, it is very easy to form aerosols in an open environment. Even in a ventilated environment, aerosol contamination cannot be avoided. Open environment processing may cause false positive results due to adulteration.

[0006] (3) The relatively closed experimental environment used in the steps including DNA extraction, loop-mediated isothermal amplification and lateral flow immunoassay can easily cause circulation contamination caused by aerosols, thereby causing false positives in adulterated results.

[0007] Therefore, there is a need to improve the existing technology. Utility Model Content

[0008] The technical problem to be solved by the utility model is to provide a meat adulteration rapid detection device which has a simple structure and is easy to use and can prevent nucleic acid aerosol contamination.

[0009] In order to solve the above technical problems, the utility model provides a meat adulteration rapid detection device that prevents nucleic acid aerosol contamination, comprising a rapid detection cartridge housing, wherein a DNA extraction chamber, a DNA amplification chamber, and an adulteration analysis chamber are respectively provided in the cavity of the rapid detection cartridge housing; a liquid outlet is provided at the bottom of the DNA extraction chamber, and the liquid outlet is connected to the inner cavity of the DNA amplification chamber through an inverted U-shaped polytetrafluoroethylene tube; the DNA amplification chamber is connected to the adulteration analysis chamber through a DNA amplification liquid transfer device;

[0010] The top of the rapid test box shell is provided with a sample adding port, an air extraction syringe connecting port and a test paper loading port, and the sample adding port and the air extraction syringe connecting port are both connected to the DNA extraction chamber.

[0011] As an improvement of the meat adulteration rapid detection device for preventing nucleic acid aerosol contamination of the utility model:

[0012] The DNA amplification chamber and the adulteration analysis chamber are both located at the bottom of the rapid test box shell and fixedly connected to the rapid test box shell, and are containers with an open top; the top of the DNA extraction chamber is fixedly connected to the top of the rapid test box shell, so that the inner cavity of the DNA extraction chamber is a closed space.

[0013] As a further improvement of the meat adulteration rapid detection device for preventing nucleic acid aerosol contamination of the utility model:

[0014] The DNA amplification liquid transfer device includes a three-way valve, which is located outside the rapid test box housing, and the three ports are respectively connected to the first polytetrafluoroethylene tube, the second polytetrafluoroethylene tube and the second air extraction syringe; after the first polytetrafluoroethylene tube and the second polytetrafluoroethylene tube each pass through the rapid test box housing, the tail of the first polytetrafluoroethylene tube is located in the DNA amplification chamber, and the tail of the second polytetrafluoroethylene tube is located in the adulteration analysis chamber.

[0015] As a further improvement of the meat adulteration rapid detection device for preventing nucleic acid aerosol contamination of the utility model:

[0016] A first air extraction syringe is provided outside the housing of the rapid test box, and the first air extraction syringe is sealedly connected to the air extraction syringe connecting port.

[0017] As a further improvement of the meat adulteration rapid detection device for preventing nucleic acid aerosol contamination of the utility model:

[0018] The adulteration analysis chamber is located directly below the test paper loading port, and the test paper loading port is used for inserting a lateral flow immunoassay test paper.

[0019] As a further improvement of the meat adulteration rapid detection device for preventing nucleic acid aerosol contamination of the utility model:

[0020] The bottom of the DNA extraction chamber is wrapped by a first heating jacket, and the bottom of the DNA amplification chamber is wrapped by a second heating jacket;

[0021] A porous filter plate is provided at the lower part of the DNA extraction chamber.

[0022] As a further improvement of the meat adulteration rapid detection device for preventing nucleic acid aerosol contamination of the utility model:

[0023] The sample adding port is provided with a cover I, and the test paper loading port is provided with a cover II. The cover I and the sample adding port, and the cover II and the test paper loading port are both detachably connected and sealed.

[0024] As a further improvement of the meat adulteration rapid detection device for preventing nucleic acid aerosol contamination of the utility model:

[0025] The rapid test box shell is a sealed rectangular parallelepiped, with a nitrogen filling pipe and a nitrogen exhaust pipe respectively provided at the diagonal positions of the top and the front side.

[0026] The beneficial effects of the present invention are mainly reflected in:

[0027] (1) The present invention adopts an independent detection system, i.e., one test box for each sample, which can avoid cross contamination between samples as much as possible;

[0028] (2) The utility model adopts a relatively closed rapid detection box, and designs the DNA extraction, DNA amplification and adulteration analysis to be carried out in a relatively closed environment, thereby avoiding the diffusion of aerosols formed during the DNA amplification process to contaminate other sample detection systems, and uses an aspiration syringe and pipeline to integrate and systematize these three links. The entire experimental process does not require the participation of external pipetting equipment, thus avoiding unnecessary contamination.

[0029] (3) The utility model adopts a gas replacement device, including a nitrogen inflation pipe on the top surface of the test box and a nitrogen exhaust pipe in the front, which can discharge the aerosol in the rapid test box into the adulteration experimental environment at any time, thereby ensuring that the entire test environment is free of aerosol contamination and avoiding circulation contamination. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The specific implementation of the present invention is further described in detail below with reference to the accompanying drawings.

[0031] Figure 1 This is a schematic diagram of the external structure of a rapid meat adulteration detection device that prevents nucleic acid aerosol contamination according to the present invention;

[0032] Figure 2 The utility model is a schematic diagram of the internal structure of a rapid meat adulteration detection device that prevents nucleic acid aerosol contamination. DETAILED DESCRIPTION

[0033] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited thereto:

[0034] Example 1: A rapid meat adulteration detection device for preventing nucleic acid aerosol contamination, such as Figure 1-2 As shown, the rapid test box housing 1 includes a sealed rectangular parallelepiped made of transparent organic glass (acrylic) with certain heat resistance and corrosion resistance.

[0035] A nitrogen inflation pipe 2 is provided at the upper right corner of the top surface of the rapid test box shell 1, and a nitrogen exhaust pipe 3 is provided at the lower left corner of the front side. Both the nitrogen inflation pipe 2 and the nitrogen exhaust pipe 3 are made of polytetrafluoroethylene tubes, which are vertically passed into the inner cavity of the rapid test box shell 1 and are sealed and fixed to the rapid test box shell 1 by means of silicone or the like, forming a replacement path for the nitrogen gas.

[0036] The top of the rapid test cartridge housing 1 is equipped with a sample loading port 6 with a lid I, a suction syringe connection port 71, a test strip loading port 9 with a lid II, and two polytetrafluoroethylene tube perforations. The sample loading port 6 is threaded, and the lid I is threadedly connected to the sample loading port 6, which acts as a seal when tightened. The suction syringe connection port 71 is an insertable interface for inserting the first suction syringe 7. It is equipped with a sealing member such as a silicone ring. After the front end of the first suction syringe 7 is inserted into the suction syringe connection port 71, the two are sealed. The test strip loading port 9 is used to insert the lateral flow immunoassay test strip 20. The test strip loading port 9 is threaded, and the lid II is threadedly connected to the test strip loading port 9, which acts as a seal when tightened.

[0037] A three-way valve 10 is provided on the rapid test box housing 1. One port of the three-way valve 10 is a suction syringe connection port 81 with a seal for inserting a second suction syringe 8. The second suction syringe 8 is sealed to the suction syringe connection port 81. The other two ports of the three-way valve 10 are connected to the head ends of a first polytetrafluoroethylene tube 16 and a second polytetrafluoroethylene tube 17, respectively. The first polytetrafluoroethylene tube 16 and the second polytetrafluoroethylene tube 17 pass through two polytetrafluoroethylene tube perforations, respectively. Both polytetrafluoroethylene tube perforations are equipped with seals such as silicone rings, thereby ensuring a sealed connection between the rapid test box housing 1 and the first polytetrafluoroethylene tube 16 and the second polytetrafluoroethylene tube 17. After passing through the polytetrafluoroethylene tube perforations, the lower portions of the first polytetrafluoroethylene tube 16 and the second polytetrafluoroethylene tube 17 are both located within the rapid test box housing 1.

[0038] The rapid test cartridge housing 1 houses a DNA extraction chamber 11, a DNA amplification chamber 15, and an adulteration analysis chamber 19. Each chamber, 11, 15, and 19 are constructed from transparent acrylic containers with open tops, allowing for easy observation of the process. Both the DNA amplification chamber 15 and the adulteration analysis chamber 19 are located at the bottom of the rapid test cartridge housing 1. The tail of the first polytetrafluoroethylene tube 16 is located within the DNA amplification chamber 15, and the tail of the second polytetrafluoroethylene tube 17 is located within the adulteration analysis chamber 19. The three-way valve 10 can selectively connect the second air extraction syringe 8 to the first polytetrafluoroethylene tube 16 or to the second polytetrafluoroethylene tube 17, respectively handling the liquid transfer operations between the DNA amplification chamber 15 and the adulteration analysis chamber 19: when the three-way valve 10 is rotated to connect the second air extraction syringe 8 to the first polytetrafluoroethylene tube 16, the reagents required for DNA amplification can be added to the DNA amplification chamber 15; after the DNA amplification is completed, the DNA amplification liquid is pumped into the syringe through the second air extraction syringe 8, and then the three-way valve 10 is rotated to connect the second air extraction syringe 8 to the second polytetrafluoroethylene tube 17 to transfer the DNA amplification solution to the adulteration analysis chamber 19.

[0039] The top of the DNA extraction chamber 11 is fixedly connected to the top of the rapid detection box shell 1 by glue, so that the inner cavity of the DNA extraction chamber 11 is a closed space, and the sampling port 6 and the air suction syringe connecting port 71 are both located within the range of the top opening of the DNA extraction chamber 11, so that the sampling port 6 and the air suction syringe connecting port 71 are connected to the inner cavity of the DNA extraction chamber 11. By unscrewing the cover I on the sampling port 6, the test sample and DNA extract can be added to the DNA extraction chamber 11. When the cover I is screwed on to seal the sampling port 6, it can be ensured that when the test sample and DNA extract in the DNA extraction chamber 11 react, the space above the DNA extraction chamber 11 is in a closed state. Then, the liquid level of the DNA extract in the DNA extraction chamber 11 is controlled by pumping or pressing by the first air suction syringe 7, so that the DNA extract solution in the DNA extraction chamber 11 can be mixed evenly.

[0040] A liquid outlet is provided at the bottom of the DNA extraction chamber 11, which is connected to the inlet end of the inverted U-shaped polytetrafluoroethylene tube 14 via a flexible tube. The outlet end of the inverted U-shaped polytetrafluoroethylene tube 14 is located within the DNA amplification chamber 15. After extraction is completed, the DNA extract is transferred into the DNA amplification chamber 15 through the inverted U-shaped polytetrafluoroethylene tube 14 by compressing the suction syringe 7. The height of the DNA extraction solution added to the DNA extraction chamber 11 must be lower than the height of the inverted U-shaped polytetrafluoroethylene tube 14. This ensures that the DNA extract can remain within the DNA extraction chamber 11 during the DNA extraction and lysis operation of the test sample, and will not be transferred from the inverted U-shaped polytetrafluoroethylene tube 14 to the DNA amplification chamber 15.

[0041] A first heating jacket 12 is disposed outside the DNA extraction chamber 11, wrapping around the bottom of the chamber to heat it. A porous filter plate 13 is located at the bottom of the chamber to prevent large sample particles from falling into and accumulating in the bottom of the chamber and in the inverted U-shaped polytetrafluoroethylene tube 14.

[0042] A second heating jacket 18 is disposed outside the DNA amplification chamber 15 . The second heating jacket 18 is used to wrap the bottom of the DNA amplification chamber 15 to heat the DNA amplification chamber 15 .

[0043] The adulteration analysis chamber 19 is located directly below the test strip loading port 9. The distance between the bottom of the adulteration analysis chamber 19 and the bottom of the test strip loading port 9 is less than the height of the lateral flow immunoassay test strip 20, and the distance between the bottom of the adulteration analysis chamber 19 and the top of the test strip loading port 9 is greater than or equal to the height of the lateral flow immunoassay test strip 20. This allows the bottom end of the inserted lateral flow immunoassay test strip 20 to extend into the adulteration analysis chamber 19 while the top end rests on the test strip loading port 9, making it easy to access. The DNA amplification chamber 15 and the adulteration analysis chamber 19 are both fixedly connected to the rapid test cartridge housing 1.

[0044] A first heating jacket temperature control switch 4 and a second heating jacket temperature control switch 5 are provided on the front panel of the rapid detection box shell 1. The first heating jacket temperature control switch 4 is electrically connected to the first heating jacket 12, and the second heating jacket temperature control switch 5 is electrically connected to the second heating jacket 18, for controlling the working status of the first heating jacket 12 and the second heating jacket 18.

[0045] The method of using the utility model is as follows:

[0046] 1. In a place where meat adulteration identification is required, place the meat adulteration rapid detection device of the present invention on a flat table and equip it with a small nitrogen cylinder and a power supply;

[0047] 2. Connect the nitrogen cylinder to the nitrogen filling pipe 2 through a hose, and connect the waste discharge pipe to the nitrogen exhaust pipe 3; turn on the nitrogen cylinder switch and slowly fill the rapid detection box housing 1 with nitrogen;

[0048] 3. Insert the first suction syringe 7 and the second suction syringe 8 into the suction syringe connection port 71 and the suction syringe connection port 81 respectively; unscrew the cover 1 on the sample addition port 6, use disposable tweezers to take 10-20 mg of sample and add it to the DNA extraction chamber 11 through the sample addition port 6, and at the same time use a pipette to add a universal one-step DNA extraction solution, then screw the cover 1 tightly onto the sample addition port 6, turn on the first temperature control switch 4, adjust the heating jacket 12 to a suitable DNA extraction lysis temperature (generally 65°C), and heat for 5-10 minutes. During the heating period, the liquid level of the DNA extraction solution in the DNA extraction chamber 11 is controlled by pumping or pressing with the first suction syringe 7 so that the DNA extraction solution can be evenly mixed;

[0049] 4. After DNA extraction is completed, turn off the first temperature control switch 4. After the DNA extract has cooled to room temperature, press the first suction syringe 7 to allow the extracted DNA extract to pass through the inverted U-shaped polytetrafluoroethylene tube 14 and enter the DNA amplification chamber 15. Then, rotate the three-way valve 10 so that the second suction syringe 8 is connected to the first polytetrafluoroethylene tube 16, and add the reagents required for DNA amplification to the DNA amplification chamber 15 through the second suction syringe 8.

[0050] Turn on the second temperature control switch 5 and adjust the second heating jacket 15 to a suitable temperature for DNA amplification (generally 55-65°C). The amplification time is generally 30 minutes. After the DNA amplification is completed, turn off the second temperature control switch 5 and wait for the DNA amplification solution in the DNA amplification chamber 15 to cool to room temperature.

[0051] 5. Draw the DNA amplification solution into the syringe through the vacuum syringe 8, then rotate the three-way valve 10 to connect the second vacuum syringe 8 with the second polytetrafluoroethylene tube 17, and transfer the DNA amplification solution to the adulteration analysis chamber 19;

[0052] Unscrew the cover II on the test strip loading port 9, use disposable tweezers to vertically insert a lateral flow immunoassay test strip 20 through the test strip loading port 9 into the bottom of the adulteration analysis chamber 19, cover and tighten the cover II, and observe the adulteration identification results.

[0053] Finally, it should be noted that the above examples are merely specific embodiments of the present invention. Obviously, the present invention is not limited to the above examples and is subject to numerous variations. All variations that can be directly derived or conceived by a person skilled in the art from the disclosure of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A rapid meat adulteration detection device to prevent nucleic acid aerosol contamination, characterized in that : It comprises a rapid test box housing (1), wherein a DNA extraction chamber (11), a DNA amplification chamber (15) and an adulteration analysis chamber (19) are respectively provided in the cavity of the rapid test box housing (1); a liquid outlet is provided at the bottom of the DNA extraction chamber (11), and the liquid outlet is connected to the inner cavity of the DNA amplification chamber (15) through an inverted U-shaped polytetrafluoroethylene tube (14); the DNA amplification chamber (15) is connected to the adulteration analysis chamber (19) through a DNA amplification liquid transfer device; The top of the rapid test box housing (1) is provided with a sample addition port (6), an air extraction syringe connection port (71) and a test paper loading port (9); the sample addition port (6) and the air extraction syringe connection port (71) are both connected to the DNA extraction chamber (11).

2. The meat adulteration rapid detection device for preventing nucleic acid aerosol contamination according to claim 1, characterized in that: The DNA amplification chamber (15) and the adulteration analysis chamber (19) are both located at the bottom of the rapid test box housing (1) and fixedly connected to the rapid test box housing (1), forming containers with an open top; the top of the DNA extraction chamber (11) is fixedly connected to the top of the rapid test box housing (1), so that the inner cavity of the DNA extraction chamber (11) is a closed space.

3. The meat adulteration rapid detection device for preventing nucleic acid aerosol contamination according to claim 2, characterized in that: The DNA amplification liquid transfer device comprises a three-way valve (10), which is located outside the rapid test box housing (1), and has three ports connected to a first polytetrafluoroethylene tube (16), a second polytetrafluoroethylene tube (17), and a second air extraction syringe (8), respectively. After the first polytetrafluoroethylene tube (16) and the second polytetrafluoroethylene tube (17) respectively pass through the rapid test box housing (1), the tail of the first polytetrafluoroethylene tube (16) is located in the DNA amplification chamber (15), and the tail of the second polytetrafluoroethylene tube (17) is located in the adulteration analysis chamber (19).

4. The meat adulteration rapid detection device for preventing nucleic acid aerosol contamination according to claim 3, characterized in that: A first air-extraction syringe (7) is provided outside the rapid test box housing (1), and the first air-extraction syringe (7) is sealedly connected to the air-extraction syringe connection port (71).

5. The meat adulteration rapid detection device for preventing nucleic acid aerosol contamination according to claim 4, characterized in that: The adulteration analysis chamber (19) is located directly below the test paper loading port (9), and the test paper loading port (9) is used for inserting a lateral flow immunoassay test paper (20).

6. The meat adulteration rapid detection device for preventing nucleic acid aerosol contamination according to claim 5, characterized in that: The bottom of the DNA extraction chamber (11) is wrapped by a first heating jacket (12), and the bottom of the DNA amplification chamber (15) is wrapped by a second heating jacket (18); A porous filter plate (13) is provided at the lower portion of the DNA extraction chamber (11).

7. The meat adulteration rapid detection device for preventing nucleic acid aerosol contamination according to claim 6, characterized in that: The sample adding port (6) is provided with a cover I, and the test paper loading port (9) is provided with a cover II. The cover I and the sample adding port (6), and the cover II and the test paper loading port (9) are both detachably connected and sealed.

8. The meat adulteration rapid detection device for preventing nucleic acid aerosol contamination according to claim 7, characterized in that: The rapid test box housing (1) is a sealed rectangular parallelepiped, with a nitrogen filling pipe (2) and a nitrogen exhaust pipe (3) respectively provided at diagonal positions on the top and front side.

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