Microfluidic chips, chip usage methods, nucleic acid detection devices and usage methods

Abstract

This invention discloses a microfluidic chip, a method for using the chip, a nucleic acid detection device, and a method for using the chip. The chip's lysis chamber is divided into a first chamber and a second chamber on its inner wall. Each chamber has a separate injection port. When a sample needs to be injected, it is injected through the corresponding injection port in the first chamber. The sample flows slowly down the inner wall to the bottom of the lysis chamber. This process avoids sample contamination if the sample is injected directly. Furthermore, the slow downward flow of the sample to the bottom of the lysis chamber prevents the sample from being suspended on top of the lysis solution, ensuring thorough mixing and improving the accuracy of subsequent result detection. In this device, the optical detection module and temperature control module are integrated into a single unit. The entire detection process does not require opening the device, avoiding contamination or influence from external light sources or air, achieving a sample-in, result-out effect.

Description

Technical Field

[0001] This invention belongs to the field of nucleic acid detection technology, and relates to microfluidic chips, chip usage methods, nucleic acid detection devices and usage methods. Background Technology

[0002] Nucleic acids carry genetic material and play a crucial role in biological genetic variation and the synthesis of various proteins, significantly influencing the occurrence and development of diseases. Qualitative and quantitative detection of specific nucleic acid sequences allows for the assessment of the tested individual's condition, which is of great significance for their health status and the prevention, diagnosis, and treatment of related diseases. With the continuous development of medical testing technology and the increasing health awareness of the public, the requirements for nucleic acid testing technology are also rising. Developing highly integrated, convenient, and automated nucleic acid testing technologies and equipment can not only improve the efficiency of nucleic acid testing but also meet the needs of areas with limited infrastructure, serving clinical applications in various environments.

[0003] Real-time quantitative PCR is currently the gold standard method for nucleic acid detection. Although this method is sensitive and reliable, it requires high professional skills from operators, involves complex testing equipment, has a long reaction time, and is costly, thus limiting its application in large-scale point-of-care diagnostics.

[0004] The combination of CRISPR technology with nucleic acid amplification technology, especially when the CRISPR / Cas system is integrated with isothermal amplification technologies such as loop-mediated isothermal amplification and recombinase polymerase amplification, and combined with droplet microfluidics technology, can achieve quantitative detection of nucleic acids. This can significantly improve the sensitivity of detection, simplify equipment, make operation simple, shorten reaction time, and reduce costs. It can make up for the shortcomings of real-time fluorescence quantitative PCR methods and meet the urgent needs of current nucleic acid detection.

[0005] While some devices exist for point-of-care testing that enable "sample in, result out," these devices are often complex and costly. Therefore, a portable, low-cost, and fast nucleic acid testing device and method are needed to fill this gap, enabling rapid, convenient, and inexpensive on-site nucleic acid testing. Summary of the Invention

[0006] The purpose of this invention is to solve the problems of inconvenient chip operation and easy sample contamination during detection in the prior art, which affects the subsequent detection results. At the same time, the existing detection devices are inconvenient to operate, have complex structures, and require professional medical personnel to operate, which limits the popularization and application of detection devices and leads to low detection efficiency. The invention provides a microfluidic chip, chip usage method, nucleic acid detection device and usage method.

[0007] To achieve the above objectives, the present invention employs the following technical solution:

[0008] A microfluidic chip includes a chip body, wherein a nucleic acid extraction and purification region and an amplification reaction region are arranged sequentially and interconnected inside the chip body;

[0009] The nucleic acid extraction and purification area includes a lysis chamber, a washing chamber, and an elution chamber connected in sequence. The lysis chamber has an inner wall, and there is a gap between the lower end of the inner wall and the bottom of the lysis chamber. The inner wall divides the interior of the lysis chamber into a first chamber and a second chamber. The upper end of the first chamber and the second chamber each have a corresponding injection port.

[0010] The amplification reaction zone includes a nucleic acid amplification detection reagent chamber, an oil phase chamber, and a microdroplet spreading chamber. The elution chamber, nucleic acid amplification detection reagent chamber, oil phase chamber, and microdroplet spreading chamber are all connected by microfluidic channels.

[0011] A further improvement of the present invention is that:

[0012] According to the microfluidic chip of the present invention, a support column is provided inside the microdroplet spreading chamber.

[0013] The chip body also has a liquid storage chamber, which is connected to the microdroplet spreading chamber.

[0014] A method of using a microfluidic chip includes the following steps:

[0015] The corresponding test solutions were injected into the lysis chamber, washing chamber, elution chamber, acid amplification detection reagent chamber and oil phase chamber, and magnetic beads were placed in the lysis chamber.

[0016] The sample to be tested is injected into the lysis chamber through the injection port corresponding to the first chamber, and the sample flows along the inner wall to the bottom of the lysis chamber.

[0017] The magnetic beads are moved by a magnet from the lysis chamber to the washing chamber and then to the elution chamber. After the magnetic beads have been eluted in the elution chamber, they are moved to the washing chamber to complete the nucleic acid extraction and purification.

[0018] The liquids in the elution chamber, the nucleic acid amplification detection reagent chamber, and the oil phase chamber are combined in the microfluidic channel to form microdroplets;

[0019] The microdroplets are transferred into the microdroplet spreading chamber to complete the sample amplification.

[0020] A nucleic acid detection device includes a detection housing, a support platform inside the detection housing, a microfluidic chip placed on the support platform, a heating element on the support platform, and an image acquisition area at the upper end of the detection housing, the image acquisition area corresponding vertically to the microfluidic chip.

[0021] An excitation light source is provided at the bottom of the detection housing, a first reflective component is provided on one side of the excitation light source, and a second reflective component is provided above the first reflective component. The first and second reflective components can reflect the light source sequentially to the microfluidic chip.

[0022] The detection housing contains a power supply box, which is used to provide power to the excitation light source and the heating element.

[0023] The support platform has a sliding groove inside, and a chip tray is slidably connected in the sliding groove. The chip tray has a slot.

[0024] Both the heating element and the microfluidic chip are housed within the card slot.

[0025] The image acquisition area includes a limiting groove, and a filter is disposed at the bottom of the limiting groove, with the filter corresponding vertically to the microfluidic chip;

[0026] An image acquisition port is provided at the upper end of the limiting groove.

[0027] The first reflective component is slidably disposed at the bottom of the inner cavity of the detection housing, and the second reflective component is slidably disposed at the top of the inner cavity of the detection housing;

[0028] The first reflective component or the second reflective component has the same structure, including a slide rail, which is disposed on the side wall of the detection housing. A reflective base is slidably connected to the slide rail, and a reflector is disposed inside the reflective base.

[0029] The end face on which the reflector is mounted on the reflector base is inclined.

[0030] An excitation light source holder is provided at the bottom of the detection housing, and the excitation light source is mounted on the excitation light source holder.

[0031] A method for using a nucleic acid testing device includes the following steps:

[0032] The excitation light source is activated, and the excitation light is emitted onto the first reflective component. After being reflected by the first reflective component, the light is emitted onto the second reflective component, and then emitted by the second reflective component to the microfluidic chip.

[0033] The heating element heats the sample inside the microfluidic chip, causing it to react.

[0034] The reaction image is acquired through the image acquisition area, and the detection result is determined based on the acquired reaction image.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] This invention discloses a microfluidic chip comprising a nucleic acid extraction and purification zone and an amplification reaction zone connected in sequence. The nucleic acid extraction and purification zone includes a lysis chamber, a washing chamber, and an elution chamber, which work together in sequence to complete purification. The lysis chamber has an inner wall that divides the interior into a first chamber and a second chamber, each with a separate injection port. When a sample needs to be injected, it is injected through the injection port in the first chamber. The sample flows slowly down the inner wall to the bottom of the lysis chamber. This process avoids the sample colliding with the internal liquid and splashing into other chambers when injected directly, thus preventing contamination of the sample or the liquid in other chambers and affecting the accuracy of the final detection results. Furthermore, the slow downward flow of the sample down the inner wall to the bottom of the lysis chamber avoids the sample being suspended at the top of the lysis buffer. This structural design allows the sample to enter the interior of the lysis buffer from top to bottom, ensuring thorough mixing between the sample and the lysis buffer and improving the accuracy of subsequent result detection.

[0037] This invention also discloses a nucleic acid detection device. A microfluidic chip is placed inside the detection housing. The internal excitation light source is sent to the microfluidic chip through a reflection path. After the reaction is completed, the reaction result is acquired through the image acquisition area at the top. In this device, the excitation light source and heating plate are all concentrated in the same device. The entire detection process does not require opening the detection device, avoiding external light sources or air from causing pollution or affecting the internal environment. It achieves the effect of sample in, result out. Moreover, the device is simple to operate, easy to carry, does not require professional assistance, and is applicable to more scenarios.

[0038] Furthermore, the first and second reflective components in this device are slidably connected and can be adjusted as needed to ensure that the light source can always accurately reach the microfluidic chip. Attached Figure Description

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0040] Figure 1 This is a schematic diagram of the overall structure of the chip of the present invention;

[0041] Figure 2 This is a diagram of the internal structure of the chip of the present invention;

[0042] Figure 3 This is a side view of the internal structure of the detection device of the present invention;

[0043] Figure 4This is a first structural diagram of the support platform for the detection device of the present invention;

[0044] Figure 5 This is a second structural diagram of the support platform for the detection device of the present invention;

[0045] Figure 6 This is a first structural diagram of the inner cavity of the detection device of the present invention;

[0046] Figure 7 This is a second structural diagram of the inner cavity of the detection device of the present invention;

[0047] Figure 8 This is a third structural diagram of the internal cavity of the detection device of the present invention.

[0048] Figure 9 This is a diagram of the external structure of the detection device of the present invention;

[0049] Figure 10 This is a structural diagram of the reflector seat on the detection device of the present invention;

[0050] Figure 11 This is a structural diagram of the lower reflector of the detection device of the present invention;

[0051] Figure 12 This is a structural diagram of the excitation light source holder for the detection device of the present invention;

[0052] Wherein: 1-Chip body; 2-Sealing plate; 3-First injection port; 4-Second injection port; 5-Third injection port; 6-Fourth injection port; 7-Fifth injection port; 8-Sixth injection port; 9-Reservoir; 10-Microdroplet spreading chamber; 11-Support column; 12-Microfluidic channel; 13-T-shaped structure; 14-Oil phase chamber; 15-Nucleic acid amplification detection reagent chamber; 16-Eluting chamber; 17-Washing chamber; 18-Cytosis chamber; 19-Inner wall; 20-Wall; 21-Detection shell; 22-Mobile phone limiting groove; 23-Picture window; 24-Slide rail; 25-Through hole; 26-Sealed slide rail; 27-Excitation light source slide rail; 28-First connection port; 29-Power supply box; 30 - Upper slide rail; 31- Limiting groove; 32- Filter port; 33- Threaded column; 34- Lower slide rail; 35- Mobile phone; 36- Support platform; 37- Sealing plate; 38- Chip tray; 39- Housing sealing plate; 40- Handle; 41- Heating element; 42- Window; 43- Notch; 44- Upper reflector seat; 45- Upper reflector limiting groove; 46- Upper slider; 47- Lower reflector seat; 48- Lower reflector limiting groove; 49- Lower slider; 50- Excitation light source seat; 51- Excitation light source limiting groove; 52- Slider; 53- Second connection port; 54- Upper reflector; 55- Macro lens; 56- Filter; 57- Lower reflector; 58- Excitation light source; 59- PCB board. Detailed Implementation

[0053] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0054] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0055] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0056] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0057] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0058] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0059] The present invention will now be described in further detail with reference to the accompanying drawings:

[0060] See Figures 1 to 12 This invention discloses a microfluidic chip, a method for using the chip, a nucleic acid detection device, and a method for using the chip. It can realize multiple functions such as nucleic acid extraction, nucleic acid amplification, nucleic acid detection, and capturing the results using a mobile phone. The entire process from nucleic acid extraction to result capture can be completed in 40 minutes, significantly simplifying the process compared to traditional nucleic acid detection methods. The accompanying portable device integrates all functional modules, requiring minimal operator skill, offering convenient operation, and providing accurate results.

[0061] See Figures 1 to 2 This embodiment discloses a microfluidic chip, including a chip body 1 and a sealing plate 2. The chip body 1 and the sealing plate 2 are sealed together by adhesive. The chip is made of transparent material. The chip body 1 has a nucleic acid extraction and purification zone and an amplification reaction zone arranged in sequence. The nucleic acid extraction and purification zone includes a lysis chamber 18, a washing chamber 17 and an elution chamber 16 arranged in sequence. The lysis chamber 18 is provided with an inner wall 19. There is a gap between the lower end of the inner wall 19 and the bottom of the lysis chamber 18. The inner wall 19 divides the interior of the lysis chamber 18 into a first chamber and a second chamber. The first chamber and the second chamber each have corresponding injection ports at their upper ends. The washing chamber 17 and the elution chamber 16 each have corresponding injection ports above them. The amplification reaction zone includes a nucleic acid amplification detection reagent chamber 15, an oil phase chamber 14 and a microdroplet spreading chamber 10. The elution chamber 16, the nucleic acid amplification detection reagent chamber 15, the oil phase chamber 14 and the microdroplet spreading chamber 10 are all connected by microfluidic channels 12.

[0062] The lysis chamber 18, washing chamber 17, and elution chamber 16 are separated by a wall 20. The first and second chambers can be filled with liquids separately. The sample is injected into the first chamber through the first injection port 3 and then enters the chamber along the inner wall 19. This sample addition method allows the sample to flow slowly downwards along the inner wall to the bottom of the lysis chamber. This process avoids the sample from colliding with the internal liquid and splashing the liquid into other chambers when it is injected directly, which would contaminate the sample or the liquid in other chambers and affect the accuracy of the final test results. Secondly, the sample flows slowly downwards along the inner wall to the bottom of the lysis chamber, avoiding the previous situation where the sample was suspended at the top of the lysis solution. This structural setting allows the sample to enter the interior of the lysis solution from top to bottom, so that the sample and the lysis solution are fully mixed, which improves the accuracy of the subsequent test results.

[0063] Furthermore, in this embodiment, a second injection port 4 is provided on the second chamber, a third injection port 5 is provided on the washing chamber 17, a fourth injection port 6 is provided on the elution chamber 16, a fifth injection port 7 is provided on the acid amplification detection reagent chamber 15, and a sixth injection port 8 is provided on the oil phase chamber 14.

[0064] Furthermore, in this embodiment, a support column 11 is provided inside the microdroplet spreading chamber 10 to prevent the microdroplet spreading chamber 10 from collapsing.

[0065] Furthermore, in this embodiment, a liquid storage chamber 9 is also provided on the chip body 1, and the liquid storage chamber 9 is connected to the microdroplet spreading chamber 10 to prevent excessive overflow of reagents in the microdroplet spreading chamber 10.

[0066] In this embodiment, the method of using the microfluidic chip includes the following steps:

[0067] The lysis buffer reagent from the nucleic acid extraction kit is injected into the lysis chamber 18 through the second injection port 4, and then the magnetic bead solution is injected into the lysis chamber 18 through the second injection port 4.

[0068] Washing liquid is injected into the washing chamber 17 through the third injection port 5;

[0069] Eluent is injected into the elution chamber 16 through the fourth injection port 6;

[0070] Amplification detection reagent is injected into the acid amplification detection reagent chamber 15 through the fifth injection port 7;

[0071] The oil required to generate microdroplets is injected into the oil phase chamber 14 through the sixth injection port 8.

[0072] The sample to be extracted and purified for nucleic acid is injected into the lysis chamber 18 through the first injection port 3. Finally, liquid paraffin oil is injected into the nucleic acid extraction and purification area of ​​the microfluidic chip through the first injection port 3 and the third injection port 5 until the entire extraction and purification chamber is filled, and the reagents in the lysis chamber 18, washing chamber 17 and elution chamber 16 are sealed.

[0073] After the sample is added, move the magnet by hand to attract the magnetic beads in the lysis chamber 18, so that the magnetic beads move from the left side to the right side of the chamber and then from the right side to the left side, repeating this cycle for 2-3 minutes; then use the magnet to gather the magnetic beads in the lysis chamber 18 together and transfer them from the lysis chamber 18 to the washing chamber 17 along the inner wall 20 through the liquid paraffin oil.

[0074] Continue using a magnet to attract the magnetic beads, causing them to move back and forth within the washing chamber 17, ensuring thorough mixing and contact with the washing solution within 17, for 2-3 minutes. Then, use a magnet to gather the magnetic beads together within the washing chamber 17, transferring them along the inner wall 20 through the liquid paraffin oil from the washing chamber 17 to the elution chamber 16. Use a magnet to attract the magnetic beads, causing them to move back and forth within the elution chamber 16, ensuring thorough mixing and contact with the eluent within 16, for 2-3 minutes.

[0075] Finally, a magnet is used to attract the magnetic beads in the elution chamber 16, and the magnetic beads are transferred from the elution chamber 16 to the washing chamber 17 along the inner wall 20. This completes the nucleic acid extraction and purification steps of the disposable microfluidic chip.

[0076] Use tape to seal the first injection port 3, the second injection port 4, and the third injection port 5.

[0077] Connect the inlet of the syringe pump to the fourth injection port 6, the fifth injection port 7, and the sixth injection port 8, respectively.

[0078] Turn on the injection pump to pressurize the eluent in the elution chamber 16, the reagent in the nucleic acid amplification detection reagent chamber 15, and the oil in the oil phase chamber 14 into the microchannel 12 connected to each chamber. The eluent in the elution chamber 16 and the reagent in the nucleic acid amplification detection reagent chamber 15 first merge in the microchannel 12, and then merge with the oil in the oil phase chamber 14 at the T-shaped structure 13 of the microchannel to generate microdroplets by shearing the aqueous phase. After that, the microdroplets enter the microdroplet spreading chamber 10 through the inlet of the microdroplet spreading chamber along the microchannel 12.

[0079] After the microfluidic chip completes the generation of microdroplets and the spreading of microdroplets in the microdroplet spreading chamber 10, the fourth injection port 6, the fifth injection port 7, the sixth injection port 8 and the liquid storage tank 9 are sealed with tape to prevent aerosol contamination in subsequent operations.

[0080] The nucleic acid amplification detection reagent used in this embodiment is an RPA-assisted one-step CRISPR / Cas12a nucleic acid detection method, which can perform specific detection of specific nucleic acid sequences. The entire amplification detection process takes twenty minutes.

[0081] See Figure 3 This embodiment also discloses a nucleic acid detection device, including a detection housing 21. A support platform 36 is disposed inside the detection housing 21, and a microfluidic chip is placed on the support platform 36. A heating element 41 is disposed on the support platform 36. An image acquisition area is formed at the upper end of the detection housing 21, corresponding vertically to the microfluidic chip. An excitation light source 58 is disposed at the bottom of the detection housing 21. A first reflective component is disposed on one side of the excitation light source 58, and a second reflective component is disposed above the first reflective component. The first and second reflective components can sequentially reflect the light source to the microfluidic chip. A power supply box 29 is disposed inside the detection housing 21, and the power supply box 29 is used to provide power to the excitation light source 58 and the heating element 41.

[0082] See Figures 4 to 5Furthermore, in this embodiment, a sliding groove is formed inside the support platform 36, and a chip tray 38 is slidably connected within the groove. A slot is formed inside the chip tray 38, and both the microfluidic chip and the heating element 41 are disposed within the slot. The heating element 41 is tightly attached to the back of the chip to ensure that the temperature of the chip chamber is consistent with the temperature of the heating element. Two windows 42 are formed on the side wall of the chip tray 38 to facilitate the connection wires of the heating element 41 to pass through the windows 42 to connect to the power supply. To prevent interference of the connection wires, corresponding notches 43 are formed on the support platform 36 to reserve space for the connection wires.

[0083] Furthermore, in this embodiment, the heating element 41 is a resistance heating element that generates resistance heat through power supply, and the temperature provided by the temperature control module in the portable testing device is 39 degrees Celsius.

[0084] The support platform 36 is inserted into the detection housing 21 via a slide rail 24 provided inside the detection housing 21. Both the support platform 36 and the chip holder 38 have handles 40 at their ends. When using a mobile phone 35 to capture the detection results of the microfluidic chip, the handles 40 are used to pull the support platform 36 and the chip holder 38, allowing the microfluidic chip to move and enabling the mobile phone 35 to complete the capture of the microdroplet spreading chamber 10 of the microfluidic chip. A through hole 25 is provided below the slide rail 24 for easy installation and removal of the heating device. Tracks are provided on both sides of the through hole 25, into which sealing plates 37 are inserted to seal the interior.

[0085] See Figures 6 to 9 Furthermore, in this embodiment, the image acquisition area structure is as follows:

[0086] The system includes a limiting groove 31 for positioning the filter, and a filter opening 32 at the lower end of the limiting groove 31 for allowing light to pass through. A limiting slide rail 30 is installed at the top of the inner cavity of the detection housing 21, and the limiting groove 31 is slidably connected to the limiting slide rail 30. A filter 56 is installed at the filter opening 32. A mobile phone limiting groove 22 is opened at the upper end of the detection housing 21 at a position corresponding to the limiting groove 31 for positioning the mobile phone. A shooting window 23 is provided inside the mobile phone limiting groove 22 for the mobile phone camera to capture the detection results. A macro lens 55 is installed at the camera of the mobile phone 35. When the mobile phone 35 is placed inside the mobile phone limiting groove 22, the center of the filter 56 and the center of the macro lens 55 are located in the same vertical plane.

[0087] Furthermore, in this embodiment, the filter 56 is circular in shape, enters from the side window of the device housing 21, and is placed in the filter limiting groove 31.

[0088] At the bottom of the inner cavity of the detection housing 21, there is a threaded post 33 for fixing the PCB board 59 of the control heating element. The PCB board 59 is fixed to the threaded post by four screws. The PCB board 59 is located below the support platform 36.

[0089] Furthermore, in this embodiment, the specific structures of the first reflective component and the second reflective component are as follows:

[0090] See Figures 10 to 11 The first or second reflective assembly has the same structure. The first reflective assembly includes a lower slide rail 34, which is located at the lower end inside the detection housing 21. A lower reflective base 47 is slidably connected to the lower slide rail 34. Lower slide blocks 49 are provided on both sides of the lower end of the lower reflective base 47. The lower reflective base 47 is provided with a lower reflector limiting groove 48 for installing a lower reflector 57. The lower reflector 57 and the lower reflector limiting groove 48 are interference-fitted.

[0091] The second reflective assembly includes an upper slide rail 30, which is located inside the upper part of the detection housing 21. An upper reflector seat 44 is slidably connected to the upper slide rail 30. Upper sliders 46 are provided on both sides of the lower end of the upper reflector seat 44. An upper reflector limiting groove 45 is provided inside the upper reflector seat 44, and an upper reflector 54 is installed inside the upper reflector limiting groove 45.

[0092] In both sets of reflective components, the reflector base can move along the slide rail to flexibly adjust the light path.

[0093] See Figure 12 The bottom of the detection housing 21 is provided with an excitation light source slide rail 27, which is slidably connected to the excitation light source seat 50. The bottom of the excitation light source seat 50 is provided with a slider 52 corresponding to the excitation light source slide rail 27. An excitation light source limiting groove 51 is opened at the upper end of the excitation light source seat 50, and the excitation light source 58 is installed inside the excitation light source limiting groove 51.

[0094] Furthermore, a sealing slide rail 26 is provided on the outside of the excitation light source 58, and a housing sealing plate 39 is inserted inside the sealing slide rail 26. The housing sealing plate 39 can seal the device housing 21 by inserting into the sealing slide rail 26. When it is necessary to install or disassemble the internal parts of the device, the housing sealing plate 39 can be pulled out from the housing 21 along the sealing slide rail 26.

[0095] Furthermore, the excitation light source has a wavelength of 450 nm.

[0096] Furthermore, the macro lens has a working distance of 20mm and a field of view of 10-11mm.

[0097] Furthermore, the reflection angle of all the mirrors is 45°.

[0098] Furthermore, in this embodiment, the power supply box 29 has a first connection port 28 and a second connection port 53 on its top, which facilitates the power connection cable to extend from the power supply box 29 and connect to the excitation light source 58 and the heating element.

[0099] Furthermore, in this embodiment, the excitation light source 58, the lower reflector 57, the upper reflector 54, the center of the filter 56, and the center of the macro lens 55 are located in the same vertical plane. The excitation optical path is as follows: the excitation light emitted by the excitation light source 58 is refracted by the lower reflector 57 and the upper reflector 54 and irradiated onto the microdroplet-laying chamber of the microfluidic chip. The excited fluorescence enters the macro lens 55 through the filter 56 and is finally captured by the camera of the mobile phone 35.

[0100] Furthermore, in this embodiment, the components of the device can be processed using 3D printing, and the material of each component is opaque plastic. The detection result is determined by the appearance of bright green dots in the photo taken by the mobile phone 35, which indicates that the sample is positive, and vice versa.

[0101] Furthermore, in this embodiment, the optical detection module and the battery box are located on opposite sides inside the portable detection device, so there is no problem of positional interference or light path obstruction.

[0102] This embodiment also discloses a method for using a nucleic acid detection device, including the following steps:

[0103] The excitation light source 58 is activated, and the excitation light source 58 emits the excitation light source onto the first reflective component. After being reflected by the first reflective component, the light source is emitted onto the second reflective component, and then emitted by the second reflective component to the microfluidic chip.

[0104] Heating element 41 heats the sample inside the microfluidic chip, causing it to react.

[0105] The reaction image is acquired through the image acquisition area, and the detection result is determined based on the acquired reaction image.

[0106] The device disclosed in this invention integrates sample extraction and purification, nucleic acid amplification, and nucleic acid detection functions, providing a detection solution that can detect different pathogens. When changing the pathogen to be detected, only the amplification detection reagent added to the chip needs to be replaced. It has good versatility, is easy to operate, and can be completed by personnel without professional training. The disclosed chip structure integrates the nucleic acid extraction and purification structure into the microfluidic chip, a function that is not commonly found in current microfluidic chips. The functions are further integrated, and the nucleic acid extraction and purification operation only requires manual movement of the magnet, making it simple to operate and meeting on-site detection needs. The device size is miniaturized, and the relevant excitation optical path has been designed and optimized, allowing results to be captured directly with a mobile phone camera. It has low dependence on location and personnel and has strong practical value.

[0107] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A microfluidic chip, characterized in that, Includes a chip body (1), wherein a nucleic acid extraction and purification zone and an amplification reaction zone are arranged in sequence inside the chip body (1); The nucleic acid extraction and purification area includes a lysis chamber (18), a washing chamber (17), and an elution chamber (16) connected in sequence. The lysis chamber (18) has an inner wall (19) inside. There is a gap between the lower end of the inner wall (19) and the bottom of the lysis chamber (18). The inner wall (19) divides the interior of the lysis chamber (18) into a first chamber and a second chamber. The first chamber and the second chamber each have corresponding injection ports at their upper ends. The chip body (1) is a vertical chip. When in use, the corresponding injection ports at the upper ends of the first chamber and the second chamber are all facing upwards. The amplification reaction zone includes a nucleic acid amplification detection reagent chamber (15), an oil phase chamber (14), and a microdroplet spreading chamber (10). The elution chamber (16), the nucleic acid amplification detection reagent chamber (15), the oil phase chamber (14), and the microdroplet spreading chamber (10) are all connected by a microfluidic channel (12).

2. A microfluidic chip according to claim 1, characterized in that, The microdroplet tiling chamber (10) is equipped with a support column (11).

3. A microfluidic chip according to claim 1, characterized in that, The chip body (1) is also provided with a liquid storage chamber (9), which is connected to the microdroplet spreading chamber (10).

4. A method of using the microfluidic chip according to claim 1, characterized in that, Includes the following steps: The corresponding test solutions are injected into the lysis chamber (18), washing chamber (17), elution chamber (16), acid amplification detection reagent chamber (15) and oil phase chamber (14), and magnetic beads are placed in the lysis chamber (18). The sample to be tested is injected into the lysis chamber (18) through the injection port corresponding to the first chamber, and the sample flows along the inner wall (19) to the bottom of the lysis chamber (18); The magnetic beads are moved by a magnet. The magnetic beads move from the lysis chamber (18) to the washing chamber (17) and the elution chamber (16) in sequence. After the magnetic beads are eluted in the elution chamber (16), they are moved to the washing chamber (17) to complete the nucleic acid extraction and purification. The liquids in the elution chamber (16), the nucleic acid amplification detection reagent chamber (15), and the oil phase chamber (14) are combined in the microfluidic channel (12) to form microdroplets; The microdroplets are transferred into the microdroplet spreading chamber (10) to complete the sample amplification.

5. A nucleic acid detection device comprising the microfluidic chip of claim 1, characterized in that, The device includes a detection housing (21), inside which a support platform (36) is provided. The microfluidic chip is placed on the support platform (36), and a heating element (41) is provided on the support platform (36). An image acquisition area is opened at the upper end of the detection housing (21), and the image acquisition area corresponds vertically to the microfluidic chip. The bottom of the detection housing (21) is provided with an excitation light source (58), a first reflective component is provided on one side of the excitation light source (58), and a second reflective component is provided above the first reflective component. The first reflective component and the second reflective component can reflect the light source to the microfluidic chip in sequence. The detection housing (21) is provided with a power supply box (29), which is used to provide power to the excitation light source (58) and the heating element (41).

6. A nucleic acid detection device according to claim 5, characterized in that, The support platform (36) has a sliding groove inside, and a chip tray (38) is slidably connected in the sliding groove. A card slot is provided in the chip tray (38). The heating element (41) and the microfluidic chip are both located in the card slot.

7. A nucleic acid detection device according to claim 5, characterized in that, The image acquisition area includes a limiting groove (31), and a filter (56) is provided at the bottom of the limiting groove (31). The filter (56) corresponds vertically to the microfluidic chip. An image acquisition port is opened at the upper end of the limiting groove (31).

8. A nucleic acid detection device according to claim 5, characterized in that, The first reflective component is slidably disposed at the bottom of the inner cavity of the detection housing (21), and the second reflective component is slidably disposed at the top of the inner cavity of the detection housing (21); The first reflective component or the second reflective component has the same structure, including a slide rail, which is set on the side wall of the detection housing (21), and a reflective seat is slidably connected on the slide rail, and a reflector is set inside the reflective seat; The end face on which the reflector is mounted on the reflector base is inclined.

9. A nucleic acid detection device according to claim 5, characterized in that, The bottom of the detection housing (21) is provided with an excitation light source base (50), and the excitation light source (58) is provided on the excitation light source base (50).

10. A method of using the nucleic acid detection device according to claim 5, characterized in that, Includes the following steps: The excitation light source (58) is activated. The excitation light source (58) emits excitation light onto the first reflector. The light source is reflected by the first reflector and emitted onto the second reflector, and then emitted by the second reflector to the microfluidic chip. Heating element (41) heats the sample inside the microfluidic chip, causing it to react. The reaction image is acquired through the image acquisition area, and the detection result is determined based on the acquired reaction image.

Images