Automatic microfluidic platform for nucleic acid purification and detection

Abstract

The invention provides an automatic micro-fluidic platform for nucleic acid purification and detection. The automatic micro-fluidic platform comprises a platform frame; the stepping motor, the array magnet and the temperature control module are sequentially fixed on the platform frame; the micro-fluidic chip comprises a nucleic acid extraction and purification chamber and a PCR (Polymerase Chain Reaction) amplification and fluorescence detection chamber; the fluorescence detection module is in driving connection with the stepping motor and comprises a multi-channel integrated PD detection module and a chip clamping groove for fixing a micro-fluidic chip; and an upper computer and a central controller. According to the automatic micro-fluidic platform provided by the invention, a series of nucleic acid extraction, purification, amplification and detection processes can be automatically carried out only by putting the micro-fluidic chip into the chip clamping groove and clicking a START button on an upper computer, the size is small and portable, and a plurality of nucleic acid samples can be simultaneously detected, so that the automatic micro-fluidic platform has a good application prospect in the field of real-time nucleic acid detection.

Description

Technical Field

[0001] The present invention relates to the technical field of nucleic acid detection, and more specifically to an automated microfluidic platform for nucleic acid purification and detection. Background Art

[0002] Nucleic acid detection technology is important and has far-reaching significance in modern medicine and biological sciences, which is mainly reflected in the following aspects: In terms of disease diagnosis, nucleic acid detection can detect pathogens (such as viruses and bacteria) in the early stages of the disease, thereby improving the rate of early diagnosis. And due to the specificity of the nucleic acid detection principle, pathogens can be accurately identified, accurate diagnosis can be achieved, and misdiagnosis can be avoided; in terms of epidemic monitoring and control, nucleic acid detection technology can quickly monitor the spread of the virus when an epidemic breaks out, providing data support for public health decision-making. It can also evaluate the immune response and effect of vaccines after vaccination by detecting the load of antibodies and viruses; in terms of personalized medicine, nucleic acid detection can help identify patients' gene mutations, thereby formulating personalized treatment plans, especially in cancer treatment. It can also be used to predict drug responses. Through genomic analysis, it can predict patients' responses to specific drugs, improve treatment effects, and reduce side effects; in terms of basic science and new drug development, nucleic acid detection technology provides important tools for research in fields such as genomics and transcriptomics, and promotes the development of life sciences. In the process of drug development, nucleic acid detection technology is used to screen and verify the targets of candidate drugs. With the development and maturity of nucleic acid testing technology, early diagnosis and personalized treatment can reduce disease complications and hospitalization rates, thereby reducing overall medical costs.

[0003] Molecular diagnostics are effective in detecting low concentrations of pathogens by nucleic acid amplification; therefore, this technology has been widely used for disease screening. Generally, it involves the following three steps: nucleic acid extraction and purification of clinical samples, removal of polymerase chain reaction (PCR) inhibitors, and then PCR amplification. The amplified nucleic acid samples are processed by fluorescence detection, colorimetric reaction, electrochemical detection and other technologies. Solid phase extraction (SPE) is a method that uses nucleic acids to bind to silica surfaces under the action of denaturants and has been widely used to purify nucleic acids. Traditional SPE methods require technicians to repeatedly centrifuge and pipette to bind nucleic acids to the silica surface and wash and elute nucleic acids from the surface. After the nucleic acids are extracted and purified, PCR amplification is performed on a thermal cycler for subsequent disease diagnosis or screening. Finally, the amplified samples are transferred to large equipment such as fluorescence microscopes and electrochemical workstations for analysis of the test results. Although molecular diagnostics can detect low concentrations of pathogens, it is limited to clinical laboratories due to the need for bulky equipment and expertise. For decades, some molecular diagnostic platforms suitable for point-of-care testing (POCT) have been realized through automated and unmanned machines that can perform near-patient testing. However, these forms of diagnosis are not suitable for detecting serious diseases in the field, such as sepsis or foodborne diseases, which require rapid screening to prevent death or critical situations. The development of molecular diagnostic technologies for POCT is also necessary.

[0004] In order to realize on-site molecular diagnosis, the procedures of sample preparation and PCR should be simplified so that the operation does not require experts and bulky equipment. Ideally, all molecular diagnostic procedures can be completed by untrained personnel even in an unpowered environment. Over the years, some isothermal methods for amplifying purified nucleic acids, including loop-mediated isothermal amplification (LAMP) and recombinase polymerase amplification (RPA), have been reported to simplify traditional PCR without the need for a thermal cycler. By performing nucleic acid amplification at a constant temperature, the need for a complex thermal cycler can be eliminated. In order to prepare samples for nucleic acid amplification, the target pathogen is separated from the original sample, and nucleic acids are extracted from the pathogen. Generally, in order to separate the target pathogen from the original sample, other impurities are removed by filtration, centrifugation or immunomagnetic beads. The most commonly used method for extracting nucleic acids from pathogens after cell lysis is to use a solid phase method based on a spin column kit. It is then washed with ethanol and eluted with distilled water. In order to simplify or automate the above sample preparation process, many microfluidic devices have been integrated together, resulting in a single device with complicated functions. In addition, some fully integrated microfluidic systems for molecular diagnosis using automated sample preparation and isothermal amplification technology have been reported. However, since microfluidic devices still require centrifuges or syringe pumps to operate, it remains challenging to achieve on-site molecular diagnostics without the need for external equipment.

[0005] In recent years, there has been a great deal of research into sample preparation tools in molecular diagnostics; these studies have demonstrated that the use of external equipment such as paper-based analytical devices and immiscible filtration assisted by surface tension (IFAST) is not necessary. Although nucleic acid purification has been successfully demonstrated, the ideal "sample-answer-output" molecular diagnostics remains elusive. Integrating other functions such as pre-concentration or isolation of pathogens from clinical samples or downstream analysis is difficult.

[0006] Most of the structures of POCT devices currently used for nucleic acid testing on the market can be divided into six parts: microfluidic chip, nucleic acid extraction and purification, amplification module, detection module, control system, and display interface. Since POCT devices do not use large instruments to achieve a one-stop detection platform for "sample-result", this limits their specificity and sensitivity, and may even lead to false negative or false positive results; although some detection devices avoid the use of PCR technology for amplification, further reducing the size of POCT devices, the isothermal amplification reagents are expensive and the primer design is complex, which makes such devices impossible to use in areas with limited resources; most of the current equipment has insufficient data processing and result analysis capabilities and cannot provide comprehensive clinical information. The most prominent problem is that most POCT devices are not highly integrated, and only realize a part of the nucleic acid detection process, and do not realize a truly fully automated nucleic acid detection process. Summary of the invention

[0007] The purpose of the present invention is to provide an automated microfluidic platform for nucleic acid purification and detection, thereby solving the problems of expensive reagents, complex primer design, low device integration, etc. in the prior art POCT equipment.

[0008] In order to solve the above problems, the present invention adopts the following technical solutions: The present invention provides an automated microfluidic platform for nucleic acid purification and detection, comprising: a platform frame; a stepper motor, an array magnet, and a temperature control module fixed on the platform frame in sequence; a microfluidic chip, which comprises: a nucleic acid extraction and purification chamber, a PCR amplification and fluorescence detection chamber; a fluorescence detection module connected to the stepper motor drive, which comprises: a multi-channel integrated PD detection module and a chip card slot for fixing the microfluidic chip, the multi-channel integrated PD detection module is spaced and aligned with the chip card slot directly above it, and the probe of the PD detection module is installed directly above the optical detection chamber of each channel; and a central control device and a host computer; wherein, driven by the stepper motor, the fluorescence detection module drives the microfluidic chip to move along the lead screw to above the array magnet. As the microfluidic chip moves, the array magnet controls the movement of the magnetic beads in the microfluidic chip to sequentially complete the nucleic acid enrichment, washing, and elution steps; subsequently, the microfluidic chip continues to move so that the microfluidic chip moves to just above the temperature control module and is in close contact with the Peltier to complete the nucleic acid amplification step; the microfluidic chip is quickly restored to room temperature through the temperature control of the Peltier. Under the control of the central controller, the multi-channel integrated PD detection module starts to work, emits excitation light, and excites the amplified nucleic acid. The multi-channel PD detection module detects the light signal emitted by the emitted light, and converts the light signal into an electrical signal for amplification and output transmission to the central controller for analysis, and finally the host computer outputs the detection result.

[0009] Preferably, the fluorescence detection module further comprises an openable L-shaped door body, wherein the L-shaped door body is fixed to the module body by hinges and is used to close the space between the PD module and the chip card slot to facilitate fluorescence detection.

[0010] Preferably, the L-shaped door body is a magnetic door, and the L-shaped door body and the module body are opened and closed by magnetic force.

[0011] Preferably, the array magnet comprises a plurality of magnets arranged in an array, the array magnet is in close contact with the microfluidic chip to control the movement of magnetic beads, and the side edge of the magnet along the moving direction of the microfluidic chip has a first chamfer to ensure that the microfluidic chip is in close contact with the magnet and moves smoothly to the designated position.

[0012] Preferably, the temperature control module comprises a pure copper heat sink and a Peltier fixed on the pure copper heat sink, and the Peltier provides the microfluidic chip with the temperature required for amplification.

[0013] Preferably, spring pressing sheets are provided at the four corners of the chip slot to ensure that the microfluidic chip is always in close contact with the Peltier during the nucleic acid extraction and purification process and the heating process.

[0014] Preferably, the side edge of the Peltier along the moving direction of the microfluidic chip has a second chamfer to ensure that the microfluidic chip is closely attached to the Peltier and moves smoothly to a designated position.

[0015] Preferably, the working surface size of the pure copper heat sink is larger than the working surface size of the Peltier to achieve better heat dissipation effect.

[0016] Preferably, the microfluidic chip adopts a ten-channel design and can detect ten nucleic acid samples simultaneously.

[0017] Preferably, the ten probes of the multi-channel integrated PD detection module are installed directly above the ten optical detection chambers on the microfluidic chip, and are used for excitation of the nucleic acids in the chambers and collection of emission light signals.

[0018] Preferably, the temperature control module further includes a cooling fan arranged behind the pure copper heat sink.

[0019] According to the present invention, a multi-channel integrated PD detection module integrates a multi-channel excitation light emitting device. The emitted light detection device converts the detected light signal into an electrical signal and amplifies the electrical signal through an amplifying circuit and then transmits it to the central controller. The central controller can obtain the fluorescence detection result by calculating and processing the returned electrical signal, and outputs the result through the host computer.

[0020] As is known to all, the prior art mainly focuses on the design and development of full-process microfluidic chips, while there are relatively few full-process nucleic acid detection devices designed for hardware equipment. In particular, full-process devices with on-chip sample preparation functions (i.e., nucleic acid extraction and purification steps) are even rarer. However, the present invention controls the movement of the microfluidic chip by a stepper motor, combines the full-process nucleic acid detection equipment with the full-process microfluidic chip, and successfully constructs a small-volume, full-function nucleic acid detection platform. The present invention also uses a magnetic bead method to extract and purify nucleic acids, achieving a higher DNA binding efficiency. Combined with a multi-channel designed microfluidic chip, it can simultaneously process the detection of multiple different nucleic acid samples. In addition, the present invention also adds chamfer designs to the side edges of the magnet and the Peltier, respectively, so that the microfluidic chip can move to the specified position more smoothly and accurately along the magnet and the Peltier. In addition, spring pressing sheets are provided at the four corners of the chip slot to ensure that the microfluidic chip is always closely fitted with the Peltier during the heating process, thereby significantly improving the heating efficiency.

[0021] An automated microfluidic platform for nucleic acid purification and detection provided by the present invention has the following beneficial effects compared with the prior art: 1) According to the present invention, driven by a stepper motor, the microfluidic chip is driven by the fluorescence detection module to move along the lead screw to the top of the array magnet. As the microfluidic chip moves, the array magnet controls the movement of the magnetic beads in the microfluidic chip to complete the nucleic acid enrichment, washing, and elution steps in sequence; then, the microfluidic chip continues to move to the top of the temperature control module to complete the nucleic acid amplification step; during the entire process, the microfluidic chip moves, and the array magnet and the temperature control module do not move. The prior art generally uses a moving magnet to manipulate the magnetic beads inside the microfluidic chip. However, if this method is used to move the magnet, the subsequent nucleic acid amplification step must rely on an additional motor to drive the temperature control device to accurately move it to the bottom of the microfluidic chip. At the same time, a motor must be configured in the vertical direction to ensure that the microfluidic chip can fit tightly on the temperature control device, so that nucleic acid amplification can be carried out smoothly. In contrast, the present invention is changed to a mobile microfluidic chip. After the nucleic acid extraction and purification step is completed, the chip can be directly moved to the top of the temperature control device. The entire microfluidic platform uses fewer operating devices and achieves better results; 2) According to the present invention, a fluorescence detection module with an ingenious design is also provided, which combines a multi-channel integrated PD detection module and a microfluidic chip together, and designs an L-shaped door body that is convenient for opening and closing. Driven by a stepper motor, the fluorescence detection module drives the microfluidic chip to move together, and automatically completes nucleic acid enrichment, washing, elution, amplification and fluorescence detection; 3) This microfluidic chip does not need to use a peristaltic pump to generate droplets and serve as a driving force for droplets like other microfluidic chips in the prior art. When pre-loading reagents, since the flow channels in the chambers of the microfluidic chip are filled with mineral oil, the reagents will automatically generate droplets in the chambers. During the whole process, the droplets do not move with the experimental process, and only the magnetic beads carry the nucleic acid molecules in the chambers, which reduces the possibility of reagent contamination; 4) Multi-sample detection: The microfluidic chip is designed with multiple channels, which can detect multiple nucleic acid samples at the same time. According to the preferred embodiment, the microfluidic chip is designed with ten channels, and accordingly, the magnet of the nucleic acid extraction and purification module of the automation platform and the multi-channel integrated PD module for fluorescence detection are designed with ten sets, which greatly improves the detection efficiency and reduces the detection cost. 5) The chamfer design of the magnet and Peltier further ensures the smooth movement of the microfluidic chip. At the same time, spring pressure pieces are installed at the four corners of the chip slot, so that the microfluidic chip can be closely combined with the high-power Peltier, so that the heating and cooling rate inside the microfluidic chip can reach 15℃ / s; 6) Small size. Since the entire drive device is composed of only one stepper motor, it is smaller and more convenient than other equipment platforms with various pumps, making it easy to carry and use outdoors. 7) The present invention realizes automated full-process nucleic acid detection. It only requires placing the microfluidic chip injected with the sample into the chip card slot and clicking the START button on the host computer. The device will automatically perform a series of nucleic acid detection processes. The entire amplification process is automated and does not require any operation by the experimenter.

[0022] In summary, the present invention provides an automated microfluidic platform that can automatically perform a series of nucleic acid extraction, purification, amplification, and detection processes. It also has the advantages of being small in size, easy to carry, and able to detect multiple nucleic acid samples simultaneously. It is particularly suitable for use in areas with limited resources, and therefore has good application prospects in the field of nucleic acid instant detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A front view of an automated microfluidic platform for nucleic acid purification and detection provided by the present invention is shown; Figure 2 It shows that Figure 1 Rear view of the automated microfluidic platform shown; Figure 3 It shows that Figure 1 A three-dimensional image of the automated microfluidic platform shown; Figure 4 shows a plan view of a microfluidic chip; Figure 5 shows a perspective view of a temperature control module; Figure 6 A perspective view of a fluorescence detection module is shown; Figure 7 A stereoscopic view of the fluorescence detection module from another viewing angle is shown. DETAILED DESCRIPTION

[0024] The present invention is further described below in conjunction with specific examples. It should be understood that the following examples are only used to illustrate the present invention and are not used to limit the scope of the present invention. The raw materials and instruments used in the following examples are all commercially available; the equipment and preparation processes used are conventional equipment and conventional processes unless otherwise specified.

[0025] Combination Figure 1~Figure 3 As shown, an automated microfluidic platform is provided according to a preferred embodiment of the present invention, which can realize automated full-process nucleic acid detection.

[0026] The automated microfluidic platform includes: a platform frame 1, a stepper motor 2, an array magnet 3, a microfluidic chip 4, a temperature control module 5, a fluorescence detection module 6, a host computer and a central controller (not shown).

[0027] The platform frame 1 provides support, and the stepper motor 2, the array magnet 3, and the temperature control module 5 are fixed on the platform frame 1 in sequence approximately along an axis.

[0028] The array magnet 3 includes a plurality of magnets arranged in an array. When the microfluidic chip 4 moves to directly above the array magnet 3 , the array magnet 3 can be closely attached to the microfluidic chip 4 to control the movement of magnetic beads in the chip.

[0029] like Figure 4 As shown, the microfluidic chip 4 includes: a nucleic acid extraction and purification chamber, a PCR amplification and fluorescence detection chamber. Preferably, the microfluidic chip adopts a multi-channel design and can detect multiple nucleic acid samples at the same time. In this embodiment, a ten-channel design is adopted, and each channel includes an extraction chamber 41, a first washing chamber 42, a second washing chamber 43, and an elution chamber 44 connected in sequence (since PCR amplification and optical detection are both performed in this chamber, this chamber is also a PCR amplification and fluorescence detection chamber), which can simultaneously realize the extraction, purification and amplification of ten nucleic acid samples. However, it should be understood that this is only used as an example and not a limitation. The microfluidic chip of the present invention is not limited to ten channels, but can also be other numbers.

[0030] like Figure 5 As shown, the temperature control module 5 includes a pure copper heat sink 51, a Peltier 52 fixed above the pure copper heat sink 51, and a cooling fan 53 arranged behind the pure copper heat sink 51. The Peltier 52 provides the microfluidic chip 4 with the temperature required for amplification.

[0031] Preferably, the working surface size of the pure copper heat sink 51 is larger than the working surface size of the Peltier 52 to achieve better heat dissipation effect. The size of the radiator is as large as possible to cover the Peltier as much as possible, but the size of the overall device must be controlled, so it is necessary to reduce the size while ensuring the heat dissipation efficiency. In this embodiment, the size of the Peltier is 40 mm * 44 mm * 3.2 mm, and the size of the heat sink is 50 mm * 50 mm * 30 mm.

[0032] Combination Figure 6 , Figure 7As shown, the fluorescence detection module 6 includes: a module body 61, a multi-channel integrated PD detection module 62, a chip card slot 63 for fixing the microfluidic chip 4, and an L-shaped door body 64. Among them, the multi-channel integrated PD detection module 62 is an optical path multi-channel integrated module, which is used for fluorescence detection of multiple channels. A PD detection probe is installed directly above the optical detection chamber of each channel. The probe can emit excitation light, collect emission light signals, and perform photoelectric signal conversion. The multi-channel integrated PD detection module 62 is spaced and aligned with the chip card slot 63 directly above it, and the probe 65 of the PD detection module is installed in the corresponding position directly above the ten detection chambers. The L-shaped door body 64 is fixed to the module body 61 by hinges, and is used to close the open space between the multi-channel integrated PD detection module 62 and the chip card slot 63 to facilitate fluorescence detection. The L-shaped door body 64 is a magnetic suction door, which is opened and closed by magnetic force between the installation of a magnetic block 66 and the module body 61.

[0033] The L-shaped door 64 can be opened or closed as needed. It can be opened when the microfluidic chip needs to be installed, and the microfluidic chip 4 can be installed in the chip slot 63. It can be closed when fluorescence detection and photography are required to seal the open space between the multi-channel integrated PD detection module 62 and the chip slot 63 to prevent external light from entering.

[0034] The four corners of the chip slot 63 are provided with spring pressing pieces 67 , which apply downward pressure to ensure that the microfluidic chip 4 is always in close contact with the Peltier 52 during the heating process.

[0035] like Figure 3 As shown, the fluorescence detection module 6 is connected to the stepper motor 2 via a lead screw 21. Driven by the stepper motor 2, the fluorescence detection module 6 can move axially along the lead screw 21, and at the same time drive the microfluidic chip 4 installed therein to move.

[0036] According to the array magnet 3 provided in the preferred embodiment, the side edge of the magnet along the moving direction of the microfluidic chip 4 has a first chamfer to ensure that the microfluidic chip 4 is closely attached to the magnet and smoothly moves to the designated position. Preferably, the first chamfer forms a smooth arc surface with a radius of 0.25 mm on the side edge of the magnet.

[0037] like Figure 5 As shown, according to the temperature control module 5 provided in the preferred embodiment, the side edge of the Peltier 52 along the moving direction of the microfluidic chip 4 has a second chamfer 54, which is used to ensure that the microfluidic chip 4 is closely attached to the Peltier 52 and smoothly moves to the specified position. Preferably, the second chamfer forms a smooth arc surface with a radius of 0.5 mm on the side edge of the Peltier 52.

[0038] The central controller uses the STM32 chip as the main control chip, which is responsible for controlling the movement of the mechanical parts of the entire equipment and the processing of electrical signals.

[0039] According to the above preferred embodiment, the automated microfluidic platform has the following workflow: Open the L-shaped door 64 and install the microfluidic chip 4 injected with the sample into the chip card slot 63; Driven by the stepper motor 2, the fluorescence detection module 6 drives the microfluidic chip 4 to move along the lead screw 21 to above the array magnet 3, and the array magnet 3 does not move. As the microfluidic chip 4 moves, the array magnet 3 controls the movement of the magnetic beads in the microfluidic chip 4, and the nucleic acid enrichment, washing, and elution steps are completed in sequence; Then, the microfluidic chip 4 continues to move so that the microfluidic chip moves to the top of the temperature control module 5 and is in close contact with the Peltier 52. The Peltier 52 provides the microfluidic chip with the temperature required for amplification, thereby completing the nucleic acid amplification step. The Peltier 52 is used to quickly cool the microfluidic chip 4 to room temperature, and the multi-channel integrated PD detection module starts to work to irradiate the excitation light to excite the amplified nucleic acid, and collects the emitted light signal to convert the light signal into an electrical signal, which is amplified by the amplifier circuit and transmitted to the central controller for data processing and calculation, and finally the detection result is obtained and output to the host computer.

[0040] The above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. The above embodiments of the present invention can also be modified in various ways. All simple, equivalent changes and modifications made according to the claims and the contents of the specification of the present invention fall within the scope of protection of the claims of the present invention. The contents not described in detail in the present invention are all conventional technical contents.

Claims

1. An automated microfluidic platform for nucleic acid purification and detection, characterized in that: include: Platform framework; A stepper motor, an array magnet, and a temperature control module are sequentially fixed on the platform frame; A microfluidic chip, comprising: a nucleic acid extraction and purification chamber, a PCR amplification and fluorescence detection chamber; A fluorescence detection module connected to the stepper motor driving device, comprising: a multi-channel integrated PD detection module and a chip card slot for fixing a microfluidic chip, wherein the multi-channel integrated PD detection module is spaced and aligned with the chip card slot directly above the chip card slot; and Host computer and central controller; Wherein, driven by the stepper motor, the fluorescence detection module drives the microfluidic chip to move along the lead screw to above the array magnet. As the microfluidic chip moves, the array magnet controls the movement of the magnetic beads in the microfluidic chip to sequentially complete the nucleic acid enrichment, washing, and elution steps. Subsequently, the microfluidic chip continues to move to move directly above the temperature control module to complete the nucleic acid amplification step. The temperature control of the temperature control module allows the microfluidic chip to quickly return to room temperature. Under the control of the central controller, the multi-channel integrated PD detection module starts to work, emitting excitation light to excite the amplified nucleic acid. The multi-channel integrated PD detection module detects the light signal emitted by the emitted light, converts the light signal into an electrical signal for amplification, and outputs and transmits it to the central controller for analysis. Finally, the host computer outputs the detection result.

2. The automated microfluidic platform according to claim 1, characterized in that: The fluorescence detection module also includes an openable L-shaped door body, which is fixed to the module body by hinges and is used to close the space between the multi-channel integrated PD detection module and the chip card slot to facilitate fluorescence detection.

3. The automated microfluidic platform according to claim 2, characterized in that: The L-shaped door body is a magnetic door, and the L-shaped door body and the module body are opened and closed by magnetic force.

4. The automated microfluidic platform according to claim 1, characterized in that: The array magnet includes a plurality of magnets arranged in an array, and the array magnet is in close contact with the microfluidic chip to control the movement of magnetic beads in the chip. The side edge of the magnet along the moving direction of the microfluidic chip has a first chamfer to ensure that the microfluidic chip is in close contact with the magnet and moves smoothly to a designated position.

5. The automated microfluidic platform according to claim 1, characterized in that: The temperature control module comprises a pure copper heat sink and a Peltier fixed on the pure copper heat sink, and the Peltier provides the microfluidic chip with the temperature required for amplification.

6. The automated microfluidic platform according to claim 5, characterized in that: The four corners of the chip slot are provided with spring pressing sheets to ensure that the microfluidic chip is always closely fitted with the Peltier during the nucleic acid extraction and purification process and the heating process.

7. The automated microfluidic platform according to claim 6, characterized in that: The side edge of the Peltier along the moving direction of the microfluidic chip has a second chamfer to ensure that the microfluidic chip can move smoothly to a designated position while being closely attached to the Peltier.

8. The automated microfluidic platform according to claim 5, characterized in that: The working surface size of the pure copper heat sink is larger than the working surface size of the Peltier to achieve a better heat dissipation effect.

9. The automated microfluidic platform according to claim 1, characterized in that: The microfluidic chip adopts a multi-channel design and can detect multiple nucleic acid samples at the same time.

10. The automated microfluidic platform according to claim 1, characterized in that: The multi-channel integrated PD detection module integrates a ten-channel excitation light source emission device and a detection device. The microfluidic chip includes a ten-channel fluorescence detection chamber. An integrated PD detection device probe is installed at a corresponding position directly above the ten-channel fluorescence detection chamber to collect the excitation and emission light of the nucleic acid in each chamber.

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