Method for extracting nucleic acid from sample solution by using magnetic beads and nucleic acid extraction module

Abstract

The invention discloses a method for extracting nucleic acid from a sample solution by using magnetic beads and a nucleic acid extraction module, and relates to the technical field of medical instruments and information intelligent equipment.The method for extracting nucleic acid from the sample solution by using the magnetic beads and the nucleic acid extraction module are characterized in that in the magnetic bead release step, a magnetic bar sleeve rotates at a high first rotating speed, and the magnetic bar sleeve rotates at a high second rotating speed; the magnetic beads are uniformly dispersed in the target solution in combination with the dissociation movement of the magnetic rod unit; and in the step of uniformly mixing the magnetic beads, the magnetic rod sleeve rotates at a lower second rotating speed, and is matched with transverse, lifting or compound motion to form a complex turbulent stirring effect, so that the magnetic beads are fully combined with the nucleic acid fragments. The invention further discloses a nucleic acid extraction module, through cooperative work of the lifting substrate, the rotary driving mechanism and the transverse driving mechanism, automatic and efficient nucleic acid extraction operation is achieved, the requirement for large-scale sample treatment is met, and meanwhile the pollution risk is reduced.

Description

Technical Field

[0001] The present invention relates to the technical fields of medical devices and information intelligent devices, and particularly relates to a method for extracting nucleic acid from a sample solution by using magnetic beads and a nucleic acid extraction module. Background Art

[0002] In vitro diagnostic technology has played an increasingly important role in the medical development in recent years. Among them, molecular diagnosis takes the nucleic acid sequence of the genetic material of an organism as the detection object, can fundamentally and efficiently identify the organisms to be detected, and is widely used in scenarios such as academic research, forensic analysis, wildlife research, and ultrasensitive diagnosis. However, obtaining high-quality nucleic acid sequences suitable for detection is an important prerequisite for realizing these applications. At present, one of the reasons for the difficult promotion of molecular diagnosis at the grass-roots level is the high technical difficulty of nucleic acid sequence acquisition. The general method requires trained professional technicians to complete it in a closed and independent space relying on specialized equipment, and it is necessary to ensure that the negative pressure in the closed space meets the requirements to reduce the risk of environmental pollution. This solution has become inadaptable under the background of the efficient development of intelligent manufacturing. Therefore, exploring a more efficient automated extraction solution is crucial for obtaining nucleic acid sequences of appropriate length and improving the yield, and will also become one of the key technologies for future development and improvement.

[0003] Magnetic bead-based nucleic acid extraction is currently the most widely used extraction method. Its core functional component, magnetic beads, contains a magnetic material core, a coating layer, and surface functional groups. It can bind nucleic acid fragments through the capture force of surface functional groups in a lysed state, and finally obtain purified nucleic acid fragments after washing and elution. Different companies have designed different extraction methods with magnetic beads. For example, the structure disclosed in U.S. Patent US20240240171A1 integrates reagent configuration and sample processing in a common large platform, and cooperates with an integrated extraction kit and a wall adsorption extraction scheme that applies electromagnetic force at the bottom to achieve batch DNA or RNA extraction and detection. However, this design poses a great risk in the inspection of highly contaminated diseases, and it is difficult for the equipment to achieve streamlined continuous operation. The solution disclosed in US20240279727A1 uses a capped tube-type extraction kit, the top of the cap can be penetrated by a pipette, and the outer wall is configured with a magnetic element to form an extraction scheme that combines wall magnetic absorption with pipetting. This method has a certain ability to prevent aerosol diffusion pollution when the cover is closed, but the specific consumables are not suitable for large-scale continuous sample processing, and the pipette tip strength requirements are high, and there is a risk of contamination when used continuously. In the molecular diagnostic equipment designed by WO2024141009A1, the extraction scheme is similar to the Antu wall extraction, and a pipette is introduced to cooperate with the pipetting transfer to realize the extraction operation, and the extraction efficiency is improved by the oscillation mixing mechanism. However, this method requires more samples to be configured in the mixing device, which is less efficient and has a higher risk of contamination, exposing that the wall extraction requires an additional mixing power source, which increases the complexity and risk of the system. The solution disclosed in CN103897987B performs lysis, washing and elution operations in different hole positions through a magnetic rod sleeve and a magnetic rod. The magnetic rod sleeve directly contacts the sample or sample processing liquid, and has a stirring function without the need for an additional oscillation function unit. However, in this structure, stirring can only be fully mixed by vertical up and down vibration, which requires a faster oscillation speed and frequency, which may lead to the risk of unreliable binding fragments or nucleic acid chains breaking into unqualified short chains.

[0004] In summary, simply and efficiently obtaining nucleic acid sequences of a qualified length is still the focus of research and development of various companies. As a key step in the extraction operation, lysis is a prerequisite for high-quality extraction results. In order to adapt to the automated large-scale sample processing system, designing an automated and efficient nucleic acid extraction method and corresponding equipment to obtain nucleic acid sequences of appropriate length and improve the product acquisition rate is a technical problem that needs to be solved urgently. Summary of the invention

[0005] The object of the present invention is: aiming at the above existing problems, the present invention provides a method for extracting nucleic acid from a sample solution by using magnetic beads and a nucleic acid extraction module. By optimizing the rotation speed, movement mode and magnetic force control in the steps of magnetic bead release, mixing and recovery, the efficiency of nucleic acid extraction and the product yield are significantly improved. In the magnetic bead release step, the magnetic rod sleeve rotates at a relatively high first rotation speed (2800 - 3200 r / min), and in combination with the extraction movement of the magnetic rod unit, the magnetic beads are evenly dispersed in the target solution; in the magnetic bead mixing step, the magnetic rod sleeve rotates at a relatively low second rotation speed (0.75 - 0.9 of the first rotation speed), and in cooperation with the horizontal, lifting or composite movement, a complex turbulent stirring effect is formed to ensure that the magnetic beads are fully combined with the nucleic acid fragments. In addition, in the magnetic bead collection step, an S-shaped collection path is formed by the horizontal and lifting movement of the magnetic rod sleeve, maximizing the magnetic bead recovery rate. The present invention also discloses a nucleic acid extraction module, which realizes automated and efficient nucleic acid extraction operations through the coordinated work of a lifting substrate, a rotation drive mechanism and a horizontal drive mechanism, meets the requirements of large-scale sample processing, and reduces the risk of contamination at the same time.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A method for extracting nucleic acid from a sample solution by using magnetic beads, comprising the following steps:

[0008] Magnetic bead transfer step: driving the magnetic rod unit to insert into the magnetic rod sleeve, making the magnetic rod sleeve in a magnetized state, adsorbing magnetic beads through the magnetized magnetic rod sleeve, and transferring the adsorbed magnetic beads into the target hole containing the target solution;

[0009] Magnetic bead release step: driving the magnetic rod unit to be withdrawn from the magnetic rod sleeve, making the magnetic rod sleeve in a weakly magnetized or demagnetized state, and at the same time driving the magnetic rod sleeve to rotate. The extraction movement of the magnetic rod unit from the magnetic rod sleeve and the rotation movement of the magnetic rod sleeve are driven simultaneously, which can cooperate with the gradually weakening magnetic force and centrifugal force to enable the magnetic beads to obtain different centrifugal forces, so that the magnetic beads can be automatically and relatively evenly dispersed in the target solution, and the magnetic beads on the magnetic rod sleeve are separated from the magnetic rod sleeve and released into the target solution;

[0010] Magnetic bead mixing step: driving the magnetic rod sleeve to perform at least one of translation, lifting or rotation in the target hole to mix the magnetic beads in the target solution and perform the target operation.

[0011] Further, in the magnetic bead release step, the magnetic rod sleeve can be driven to rotate at a first rotation speed, and in the magnetic bead mixing step, the magnetic rod sleeve can be driven to rotate at a second rotation speed. The range of the first rotation speed is 2800 - 3200 r / min, and the second rotation speed is 0.75 - 0.9 of the first rotation speed.

[0012] Further, it also includes a magnetic bead collection step: after the target operation is completed, the magnetic rod unit is driven to re-insert into the magnetic rod sleeve, so that the magnetic rod sleeve is in a magnetized state. The magnetized magnetic rod sleeve is driven to move within the target hole position, so that the magnetic beads in the target solution are re-adsorbed onto the magnetic rod sleeve, and the magnetic beads are transferred to the next work station through the magnetized magnetic rod sleeve.

[0013] Further, in the magnetic bead collection step, first drive the magnetic rod sleeve to move to a position matching the top liquid level of the target solution, then drive the magnetic rod unit to re-insert into the magnetic rod sleeve to make the magnetic rod sleeve in a magnetized state. After that, drive the magnetized magnetic rod sleeve to move horizontally within the target hole position. When the horizontal movement reaches the maximum distance, drive the magnetized magnetic rod sleeve to descend a preset depth and then reverse for reverse horizontal movement. Repeat this process to make the magnetized magnetic rod sleeve form an S-shaped collection path with at least one detour. When the magnetized magnetic rod sleeve descends to the lowest position of the target hole, drive the magnetic rod sleeve to rise and fold back along the S-shaped collection path, so that the remaining magnetic beads are collected on the magnetized magnetic rod sleeve.

[0014] Further, in the magnetic bead collection step, the preset amplitude of the horizontal movement is 2.5 - 4 times the average hydraulic diameter of the magnetic rod sleeve.

[0015] Further, in the magnetic bead release step, the total distance that the magnetic rod unit withdraws from the magnetic rod sleeve is a set value, and this set value is 10 - 20 times the average hydraulic diameter of the magnetic rod sleeve.

[0016] Further, when extracting nucleic acid from the sample liquid, the lysis operation, washing operation, and elution operation need to be performed in sequence. The lysis operation, washing operation, and elution operation all need to perform the magnetic bead transfer step, magnetic bead release step, magnetic bead mixing step, and magnetic bead collection step in sequence; in the lysis operation, the target hole position is the lysis hole, and the target solution is the sample liquid added with the lysis buffer; in the washing operation, the target hole position is the washing hole position, and the target solution is the washing buffer; in the elution operation, the target hole position is the elution hole position, and the target solution is the elution buffer.

[0017] A nucleic acid extraction module performs nucleic acid extraction operations using the method of extracting nucleic acid from a sample solution using magnetic beads as described in any one of claims 1-6. It includes an extraction module main body, in which a first lifting substrate, a first substrate driving motor, a first substrate transmission screw rod, a second lifting substrate, a second substrate driving motor, a second substrate transmission screw rod, a vertical slide rail, and a vertical substrate are provided. A magnetic rod unit is connected to the first lifting substrate, and a magnetic rod sleeve loading unit is connected to the second lifting substrate. The magnetic rod sleeve loading unit is hollow and one end thereof can be connected to a magnetic rod sleeve, and the magnetic rod unit can pass through the magnetic rod sleeve loading unit and extend into the magnetic rod sleeve. The vertical slide rail is connected to the vertical substrate, and the first lifting substrate and the second lifting substrate are respectively movably connected to the vertical slide rail through sliders, and the first lifting substrate is always arranged at a higher position relative to the second lifting substrate. The first substrate driving motor is assembled on the second lifting substrate and is connected to the first lifting substrate through the first substrate transmission screw rod. The first substrate driving motor can drive the first lifting substrate to move relative to the second lifting substrate along the vertical slide rail, changing the relative distance between the first lifting substrate and the second lifting substrate. The second substrate driving motor is assembled on the vertical substrate and is connected to the second lifting substrate through the second board transmission screw rod. The second substrate driving motor can drive the first lifting substrate and the second lifting substrate to move synchronously along the vertical slide rail. The first substrate transmission screw rod and the second substrate transmission screw rod are arranged in an opposite-toppling manner with opposite orientations.

[0018] Further, a lateral driving mechanism is further included in the extraction module main body. The lateral driving mechanism is connected to the vertical substrate and can drive the vertical substrate to move horizontally. The lateral driving mechanism includes a lateral driving motor, a lateral screw rod, a lateral slide rail, a lateral connecting block, and a lateral slider. The lateral driving motor is connected to the lateral screw rod. A lateral connecting block is in threaded engagement with the lateral screw rod. The bottom end of the lateral connecting block is connected to the lateral slider, and the top end is connected to the vertical substrate. The lateral slider is connected to the lateral slide rail arranged parallel to the lateral screw rod, and the lateral slider can move along the extending direction of the lateral slide rail under the drive of the lateral driving motor.

[0019] Further, a rotation driving mechanism is further configured on the second lifting substrate. The rotation driving mechanism includes a rotation driving motor, a rotation driving gear, an intermediate gear, and a rotation transmission gear. The rotation transmission gear is provided at the end of the magnetic rod sleeve loading unit. A plurality of magnetic rod sleeve loading units are arranged side by side, and the rotation transmission gears corresponding to adjacent magnetic rod sleeve loading units are meshed and driven with each other. The rotation driving gear is meshed and connected to the intermediate gear, and the intermediate gear is meshed and connected to any one of the rotation transmission gears. The rotation driving motor can drive the magnetic rod sleeves to rotate at a first speed and a second speed respectively. The range of the first speed is 2800-3200 r / min, and the second speed is 0.75-0.9 of the first speed.

[0020] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0021] 1. The extraction method of the present invention utilizes magnetic beads in combination with a magnetic rod and a magnetic rod sleeve to perform multiple steps of operation in the target wells. In the magnetic bead release step, the magnetic rod sleeve rotates at a relatively high first speed (2800-3200r / min), generating a greater centrifugal force, which is conducive to the magnetic beads being dispersed in the target wells more quickly. In the magnetic bead mixing step, the magnetic rod sleeve rotates at a relatively low second speed (0.75-0.9 of the first speed), which can generate sufficient turbulence without causing pollution risks such as splashing. The relatively high-speed rotation time in the magnetic bead release step is less than the lower-speed rotation time in the magnetic bead mixing step, and the second speed is controlled to be 0.75-0.9 of the first speed, so that the speed of the magnetic rod sleeve in different steps adapts to different functions. Optimally, the rotation direction of the rotational motion in the magnetic bead release step and the magnetic bead mixing step is the same, so that even when switching at different speeds, it can be switched smoothly, and will not cause excessive turbulence in the liquid in the target wells.

[0022] 2. The volume of the lysis well is configured to be larger than the volume of the washing well or the elution well, so that a larger amount of sample liquid can be processed, and sufficient movement space is provided for the lateral movement of the magnetic rod sleeve. The composite movement is used to form a more sufficient stirring and mixing effect, which is also more suitable for high-sensitivity detection scenarios with low target loads.

[0023] 3. The magnetic bead collection step makes the lateral movement of the magnetic rod sleeve coordinated with the lifting movement, which can more fully collect all the magnetic beads in the target hole position and maximize the product acquisition rate. The amplitude of the lateral movement is configured to be 2.5-4 times the average hydraulic diameter of the magnetic rod sleeve, which can form a reasonable turbulence on the one hand, and on the other hand, it will not cause the problem of a small liquid level at the target hole position that is not conducive to operation.

[0024] 4. In the magnetic bead mixing step, the rotational motion at the second speed can be combined with the lateral reciprocating movement, or the rotational motion at the second speed can be combined with the lifting and lowering oscillating motion, or a composite motion such as the three occurring simultaneously, or a combination of different composite motions in multiple time periods, to form a stirring effect with complex turbulent directions that is more suitable for mixing, so that the magnetic beads are more evenly dispersed and more fully combined with the nucleic acid fragments of the target solution.

[0025] 5. In the magnetic bead release step, the movement of the magnetic rod unit pulling out of the magnetic rod sleeve and the rotational movement at the first rotational speed are simultaneously driven, which can cooperate with the gradually weakening magnetic force and centrifugal force to enable the magnetic beads to obtain different centrifugal forces, and then the magnetic beads can be automatically and relatively evenly dispersed within a wider range. The total distance that the magnetic rod unit can be driven to move out is a set value, which is 10 - 20 times the average hydraulic diameter of the magnetic rod sleeve, so that the part of the magnetic rod sleeve immersed in the target solution can be fully demagnetized, and there is basically no risk of the magnetic beads being pulled out during the operation.

[0026] 6. The present invention also discloses a nucleic acid extraction module, which utilizes two lifting substrates driven to move, and respectively connects the magnetic rod unit and the magnetic rod sleeve loading unit. The magnetic rod sleeve loading unit is also connected with a rotational driving mechanism, and the rotational driving motor can drive the connected magnetic rod sleeve to rotate at a higher first rotational speed or at a lower second rotational speed to adapt to the difference in functional requirements at different stages in the target operation, where the second rotational speed is 0.75 - 0.9 of the first rotational speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a flowchart of the method for extracting nucleic acid from a sample solution using magnetic beads in the present invention;

[0028] Figure 2 is a schematic diagram of the process of the magnetic bead release step in the present invention;

[0029] Figure 3 is a diagram of the compound movement mixing method for the magnetic bead mixing step provided by the present invention;

[0030] Figure 4 is a schematic diagram of the process of the magnetic bead collection step provided by the present invention;

[0031] Figure 5 is the overall structure diagram of the extraction module;

[0032] Figure 6 is a schematic diagram of the structure of the rotational driving mechanism;

[0033] Figure 7 is a schematic diagram of the structure of the mutually cooperating rotational transmission gears;

[0034] Figure 8 is a state diagram of the magnetic rod unit passing through the hollow magnetic rod sleeve loading unit;

[0035] Figure 9 is a schematic diagram of the structure of the lateral movement driving structure;

[0036] Figure 10 is a structure diagram of the cassette loading position;

[0037] Figure 11It is a process diagram of the cartridge loading position being driven out beyond the main body range of the extraction module block;

[0038] Figure 12 It is a process diagram of the cartridge loading position receiving the extraction kit;

[0039] Figure 13 It is a process diagram of the cartridge loading position being driven back into the main body range of the extraction module;

[0040] Figure 14 It is a process diagram of the magnetic rod sleeve loading unit being driven to pick up and load the magnetic rod sleeve within the extraction kit 30;

[0041] Figure 15 It is a process diagram of the magnetic rod sleeve loading unit completing the loading of the magnetic rod sleeve;

[0042] Figure 16 It is a state diagram of the loaded magnetic rod sleeve performing lysis within the lysis holes of the extraction kit;

[0043] Figure 17 It is a state diagram of the loaded magnetic rod sleeve performing elution within the elution holes of the extraction kit;

[0044] Figure 18 It is an overall diagram of the extraction module configured within the housing.

[0045] Markings in the figure: 10 - magnetic rod unit, 11 - first substrate driving motor, 12 - first substrate driving lead screw, 13 - first lifting substrate, 14 - sensing piece, 15 - detector, 20 - magnetic rod sleeve loading unit, 21 - second substrate driving motor, 22 - second substrate driving lead screw, 23 - second lifting substrate, 24 - induction piece, 25 - induction component, 30 - extraction kit, 31 - rotation driving motor, 32 - rotation driving gear, 34 - intermediate gear, 331, 332, 333, 334 - rotation transmission gears, 41 - loading driving motor, 42 - loading transmission gear, 43 - loading transmission rack, 50 - cartridge loading position, 51 - lateral driving motor, 52 - lateral lead screw, 53 - lateral connection block, 100 - housing, 151 - detection assembly plate, 201 - hollow part, 202 - bearing, 501 - roller, 502 - module chamber door, 503 - lysis heating element, 504 - elution heating element, 505 - cartridge limiting part, 60 - vertical substrate, 601 - vertical slide rail, 602 - lateral slider, 603 - lateral slide rail, 70 - fan assembly, 701 - filter element. Detailed implementation manners

[0046] The present invention will be described in detail below with reference to the accompanying drawings.

[0047] In order to make the objectives, technical solutions and advantages of the present invention more clear and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0048] Embodiment 1

[0049] Embodiment 1

[0050] Figure 1 is a flowchart of the method for extracting nucleic acid from a sample solution using magnetic beads in the present invention; the magnetic rod unit 10 of the present invention can be inserted into or withdrawn from the magnetic rod sleeve, and by inserting it to a set depth, the magnetic rod sleeve outside it has a specific intensity of magnetism, especially the bottom area of the magnetic rod sleeve and the part immersed in the liquid have a specific intensity of magnetism. Withdrawing the magnetic rod unit 10 from the bottom of the magnetic rod sleeve can weaken the magnetism around the magnetic rod sleeve to present a weak magnetism or a completely demagnetized state. Using this characteristic, the adsorption or detachment of magnetic beads can be realized. In nucleic acid extraction, the magnetic rod unit 10 can be inserted into the magnetic rod sleeve to form a magnetized magnetic rod sleeve. In the magnetic bead storage hole, it can adsorb the magnetic beads in the hole using the magnetic characteristics presented on the outer wall surface of the magnetic rod sleeve and be synchronously driven to transfer to the lysis hole position to perform the lysis operation. Here, the lysis operation includes the magnetic bead release and magnetic bead mixing steps; in the magnetic bead release step, the magnetic rod unit 10 is driven to withdraw from the magnetic rod sleeve to weaken or demagnetize the magnetic rod sleeve, and the magnetic rod sleeve is driven to rotate at a first rotation speed. Here, the withdrawal movement of the magnetic rod unit 10 and the rotation movement of the magnetic rod sleeve are simultaneously driven, which can cooperate with the gradually weakening magnetic force and centrifugal force to enable the magnetic beads to obtain different centrifugal forces, and then automatically and relatively evenly disperse the magnetic beads over a wider range; in the magnetic bead mixing step, the magnetic rod sleeve can be driven to rotate at a second rotation speed, where the first rotation speed is greater than the second rotation speed. In this way, even when switching between different rotation speeds, a smooth switch can be achieved without causing excessive turbulence in the liquid in the lysis hole position. The suitable range of the first rotation speed is within 2800 - 3200 r / min to ensure sufficient and appropriate centrifugal force. To ensure more uniform mixing of the magnetic beads in the magnetic bead mixing step, the rotational movement is also combined with movements in other directions to form a more complex mixing movement, which can include maintaining the second rotation speed and being driven to move reciprocally in the horizontal direction, maintaining the second rotation speed and being driven to move up and down, and a combined movement of maintaining the second rotation speed and moving reciprocally in the horizontal direction and moving up and down at the same time, etc. At this time, the problem of excessive turbulence and splashing caused by a single direction can also be avoided. In the combined movement, the multi-dimensional mixing movement is also more suitable for the extraction and stirring scenario, enabling the magnetic beads to be widely and evenly dispersed in the lysis hole position, and the coating layer of the magnetic beads can more efficiently and fully bind to the nucleic acid fragments released by lysis. Then, the magnetic rod unit 10 can still be inserted into the magnetic rod sleeve to form a magnetized magnetic rod sleeve to collect the magnetic beads and complete the lysis operation, and it also includes a washing operation performed in the washing hole position and an elution operation performed in the elution hole position, finally obtaining the extracted and purified nucleic acid fragments.

[0051] Figure 2 This is a schematic diagram of the process of the magnetic bead release step of the present invention; the magnetic rod unit 10 is inserted into the magnetic rod sleeve, so that the outer wall surface of the magnetic rod sleeve has a specific magnetic field strength. The two cooperate to adsorb the magnetic beads to the outer wall surface of the magnetic rod sleeve in the magnetic bead storage hole position, and then are transferred to the lysis hole position. In order to ensure that the magnetic beads are more widely dispersed, the magnetic rod sleeve is immersed in the liquid at a higher position in the lysis hole position and rotates at a higher first rotational speed. While rotating, the magnetic rod unit 10 is driven to be withdrawn from the magnetic rod sleeve, forming a gradually weakening magnetic field. The magnetic beads attached to the outer wall surface of the magnetic rod sleeve obtain different centrifugal forces and are thus evenly dispersed over a wider range. The process is as shown in a. The magnetic rod sleeve can remain at this position for a specific time, such as intervals of 1, 1.5, 2, 2.5, 3 s, etc. It can also use the gravity to make the magnetic beads be more evenly distributed in the depth direction, as shown in b. During the period when the magnetic rod unit 10 is withdrawn from the magnetic rod sleeve, the magnetic rod sleeve always maintains a high-speed rotational motion at the first rotational speed at the same position. The total distance that the magnetic rod unit 10 can be driven to withdraw is a set value, and this set value is 10-20 times the average hydraulic diameter of the magnetic rod sleeve, so that the magnetic rod sleeve can be basically in a non-magnetic state and can perform the mixing operation more fully in the subsequent mixing step, as shown in c. After maintaining the rotational motion for a specific time, the magnetic rod sleeve can also be driven to move downward and maintain a high first rotational speed during the downward movement, so that the magnetic beads are fully released.

[0052] Figure 3It is a diagram of the composite motion mixing method for the magnetic bead mixing step provided by the present invention; after the magnetic bead release step is completed, the magnet rod sleeve in the micro-magnetized or demagnetized state can be driven to perform the magnetic bead mixing step. The magnet rod sleeve directly contacts the liquid in the lysis hole position and can produce an efficient stirring effect by driving its movement. A more complex composite motion can reduce the turbulence degree in a single direction, and the composite rotational motion can reduce the shearing force acting on the nucleic acid sequence to ensure that the extracted nucleic acid sequence has an appropriate length. As shown in d, it is a type of composite motion. The lateral movement of the magnet rod sleeve is introduced to meet the spatial requirements of the lateral movement. The volume of the lysis hole position is larger than that of the washing hole position or the elution hole position. The lysis hole position has a width feature that enables the magnet rod sleeve to move laterally by a preset amplitude. Here, the preset amplitude of the lateral movement is 2.5 - 4 times the average hydraulic diameter of the magnet rod sleeve, so that the volume of the lysis hole position will not be too large to cause too small a liquid depth and relatively serious wall adhesion loss, nor will the lateral width of the lysis hole position be too small to make the lateral movement amplitude too small to generate sufficient turbulent stirring. During the lateral swinging motion, the magnet rod sleeve can also rotate at a second rotational speed lower than the first rotational speed. Here, the optimal configuration of the second rotational speed is 0.75 - 0.9 times the first rotational speed, and the rotational directions of the two are preferably the same, so as not to generate too much turbulence during the switching of different steps and cause the risk of splash contamination; as shown in e, during the process of driving the magnet rod sleeve to move up and down, it is also accompanied by a composite motion of rotating at the second rotational speed. During this process, the speed of driving the magnet rod sleeve to move up and down can be greater than the speed of driving the magnetic rod unit 10 to extract the magnet rod sleeve. In this way, the change in the magnetic field force during the magnetic bead release step can be made slower, and the magnetic beads can obtain a wider range of centrifugal forces. A greater lifting and lowering speed of the magnet rod sleeve can introduce more sufficient turbulent action in the vertical direction and meet the different requirements of different steps; as shown in f, it is a more complex composite motion formed by combining the lifting and lowering motion, the lateral motion, and the rotational motion. The rotational motion speed is still the second rotational speed, and the lateral movement speed and the lifting and lowering motion speed can be the same as before; in actual use, one of the above-mentioned composite motions can be arranged in the mixing step, or different composite motions can be arranged in different time periods during the lysis process to form a more complex composite motion mode, which is not limited here.

[0053] Figure 4It is a schematic diagram of the process of the magnetic bead collection step provided by the present invention; in the magnetic bead collection step, the magnetized magnetic rod sleeve can be driven to move horizontally in the width direction of the lysis hole position multiple times. The magnetization method is that the magnetic rod unit 10 is reinserted into the magnetic rod sleeve. In order to collect the magnetic beads binding nucleic acid fragments in the lysis hole position as residue-free as possible, multiple horizontal movements and intermittent lowering movements of the magnetic rod sleeve are introduced in this step. Specifically, it can be driven to descend a preset depth at the maximum distance of each horizontal movement and then repeat the horizontal movement. The entire movement path presents an S-shaped magnetic bead collection path trajectory. Here, the distance of each descent can be designed to be the same or different intervals. After descending to the lowest position, it can be further driven to move upward along the S-shaped path to ensure that the magnetic beads can be collected with basically no residue.

[0054] Example 2

[0055] The present invention also provides a nucleic acid extraction module capable of automatically performing the extraction method of Example 1. Figure 5It is the overall structure diagram of the extraction module; the extraction module includes an upper part capable of lifting movement and a lower part capable of telescopic movement. The upper part includes a vertical substrate 60, on which a vertical slide rail 601 is fixedly connected. The preset extended height of the vertical substrate 60 can be set to 1.5 to 3 times the length dimension of the magnetic rod unit 10 connected thereto. In this way, it can ensure that the magnetic rod unit 10 has sufficient lifting movement stroke, and at the same time, the lifting movement time will not be too long to affect the extraction efficiency or control accuracy. The first lifting substrate 13 and the second lifting substrate 23 are respectively connected to different positions on the vertical slide rail 601 in an engaged manner through two sliders. In order to enable the first lifting substrate 13 and the second lifting substrate 23 to operate precisely without interference on the same vertical slide rail 601, the first lifting substrate 13 and the second lifting substrate 23 have a relative height configuration relationship, where the first lifting substrate 13 is always arranged at a higher position relative to the second lifting substrate 23 on the vertical slide rail 601. A magnetic rod unit 10 is fixedly connected to the first lifting substrate 13, and a magnetic rod sleeve loading unit 20 is fixedly connected to the second lifting substrate 23. In this way, it can rely on the independent upward movement of the first lifting substrate 13 at a higher position to keep the second lifting substrate 23 at a lower position stationary, and can weaken the magnetic field around the magnetic rod sleeve connected to the magnetic rod sleeve loading unit 20 or even completely demagnetize the bottom area under basically static conditions, which is more suitable for the execution of efficient extraction operations; the first lifting substrate 13 is driven to move by the first substrate driving motor 11. Here, the first substrate driving motor 11 outputs and is connected to the first substrate driving lead screw 12, and the first substrate driving lead screw 12 is also directly or indirectly threadedly engaged with the first lifting substrate 13. For example, threads can be configured locally on the first lifting substrate 13 to directly connect it to the first substrate driving lead screw 12, or a connecting block with threads can be connected to the first lifting substrate 13 and then indirectly connected to the first substrate driving lead screw 12. In this way, the rotational movement of the first substrate driving motor 11 can be converted into the up and down sliding movement of the first lifting substrate 13 along the vertical slide rail 601;The second lifting substrate 23 is driven by a similar lifting motion. Here, the output of the second substrate driving motor 21 is connected to the second substrate transmission lead screw 22. The second substrate transmission lead screw 22 is also directly or indirectly threadedly engaged with the second lifting substrate 23, which can convert the rotational motion of the second substrate driving motor 21 into the up-and-down sliding motion of the second lifting substrate 23 along the vertical slide rail 601. The second lifting substrate 23 is also fixedly connected to the first substrate driving motor 11. Thus, the second lifting substrate 23 can also drive the first lifting substrate 13 to move synchronously in a state with a fixed spacing. In this way, during the extraction operation, such as during the magnetic bead transfer and mixing processes, the magnetic rod unit 10 and the magnetic rod sleeve can move synchronously, and the magnetic field generated by the magnetic rod unit 10 around the magnetic rod sleeve connected to the magnetic rod sleeve loading unit 20 will not change. Using a single motor to achieve the synchronous lifting motion control of the first lifting substrate 13 and the second lifting substrate 23 has low difficulty and high reliability. The first substrate driving motor 11 and the second substrate driving motor 21 are arranged in a counter-rotating manner such that the connected first substrate transmission lead screw 12 and the second substrate transmission lead screw 22 face in opposite directions to improve the space utilization rate in the limited space. The second substrate driving motor 21 is fixedly connected to the vertical substrate 60 that fixes the vertical slide rail 601. An inductor 25 is also arranged on the second substrate driving motor 21. The inductor 25 can obtain the distance data from the second lifting substrate 23 to the second substrate driving motor 21, and limit the highest position of the second lifting substrate 23 according to the obtained distance data, and can also be used to calibrate the movement position of the second lifting substrate 23. The second lifting substrate 23 is also fixedly connected to a detection assembly plate 151. The detector 15 is fixedly connected to the detection assembly plate 151 at a preset spacing from the reference plane of the second lifting substrate 23. When the first lifting substrate 13 moves to the same height as the detector 15, the detector 15 is triggered by the sensing piece 14 connected to the first lifting substrate 13, so that it can limit the maximum spacing between the first lifting substrate 13 and the second lifting substrate 23. The maximum spacing here is set to the maximum distance for the magnetic rod unit 10 to withdraw from the magnetic rod sleeve, which can be 10 - 20 times the average hydraulic diameter of the magnetic rod sleeve, making the demagnetization of the magnetic rod sleeve more thorough, and can also be used as a reference position calibrator for the up-and-down movement of the first lifting substrate 13. To simplify the control, the sensing piece 24 that cooperates with the inductor 25 is fixedly connected to the detection assembly plate 151 here. Of course, a part of the detection assembly plate 151 can also be directly processed into the sensing piece 24. The second lifting substrate 23 is also configured with a rotation driving mechanism. The rotation driving mechanism includes a rotation driving motor 31, which can drive the magnetic rod sleeve loading unit 20 to rotate through a rotation transmission mechanism, and then drive the connected magnetic rod sleeve to rotate. By changing the rotation speed of the driving motor 31, different rotation speeds suitable for the magnetic bead release step and the magnetic bead mixing step can be output. Among them, the magnetic bead release step can be configured with a higher first rotation speed, and the mixing step is a lower second rotation speed;The lower part of the extraction module further includes a cassette loading position 50. The cassette loading position 50 can be driven by the loading drive motor 41 to extend outside the range of the extraction module main body to receive the extraction reagent kit 30. In order to reduce the movement resistance of the cassette loading position 50, at least one roller 501 needs to be configured at its bottom; the vertical substrate 60 of the extraction module can be threadedly connected to the transverse lead screw 52 of the transverse drive mechanism through the transverse connecting block 53, so that the vertical substrate 60 can slide along the extension direction of the transverse slide rail 603. Here, the vertical substrate 60 can also be fitted with the transverse slide rail 603 through the transverse slider 602.;

[0056] Figure 6 is a schematic structural diagram of the rotation drive mechanism, Figure 7 is a schematic structural diagram of the rotation transmission gears cooperating with each other; the second lifting substrate 23 is also fixedly connected with a rotation drive motor 31. For the convenience of installation and reliable transmission, the rotation drive motor 31 is inversely assembled on the second lifting substrate 23. The rotation drive motor 31 has a preset distance from the plane of the second lifting substrate 23. The output shaft of the rotation drive motor 31 is connected to the rotation drive gear 32. Here, in order to obtain a suitable transmission ratio and more reliable and efficient transmission, the rotation drive gear 32 is also meshingly connected to the intermediate gear 34. The intermediate gear 34 can be directly meshingly connected to one of the rotation transmission gears 331, 332, 333, or 334 assembled in one end region of any one of the magnetic rod sleeve loading units 20. Here, the number of the magnetic rod sleeve loading units 20 is 4. In one end region of each of them, rotation transmission gears 331, 332, 333, and 334 are respectively connected. The four rotation transmission gears 331, 332, 333, and 334 are meshingly driven in pairs. In order to reduce the resistance in the rotational movement of the magnetic rod sleeve loading unit 20, bearings 202 are correspondingly arranged in the end regions where each magnetic rod sleeve loading unit 20 is connected to the rotation transmission gears 331, 332, 333, and 334. In order to cooperate with the magnetic rod unit 10 to perform nucleic acid extraction operations, each magnetic rod sleeve loading unit 20 has a hollow part 201 inside, so that the magnetic rod unit 10 can pass through the magnetic rod sleeve loading unit 20. The number of the magnetic rod units 10 and the magnetic rod sleeve loading units 20 is the same, and can be 3, 4, 5, 6, 7, 8, and so on. Here, the rotation drive gear 32 is indirectly meshingly driven with each intermediate gear 34 and connected to any one of the four rotation transmission gears 331, 332, 333, or 334. In this way, the rotational movement output by the rotation drive motor 31 can be converted into the rotational movement of the multiple magnetic rod sleeve loading units 20 connected to the rotation transmission gears 331, 332, 333, and 334.

[0057] Figure 8It is a state diagram of the magnetic rod unit 10 passing through the hollow magnetic rod sleeve loading unit 20; here, in order to clearly show the state of the magnetic rod unit 10 penetrating the magnetic rod sleeve loading unit 20, the lower part of the magnetic rod sleeve loading unit 20 is not connected to the magnetic rod sleeve. During this process, the second substrate driving motor 21 rotates to make the second lifting substrate 23 rise a preset distance along the vertical slide rail 601. Since it is also fixedly connected to the first substrate driving motor 11, it can indirectly drive the first lifting substrate 13 to rise synchronously by a preset distance. Before this, the first substrate driving motor 11 can rotate to change the distance between the first lifting substrate 13 and the second lifting substrate 23. Here, the first substrate driving motor 11 can drive the first lifting substrate 13 to descend, so that the magnetic rod unit 10 penetrates more into the hollow part of the magnetic rod sleeve loading unit 20, and more magnetic rod units 10 pass through the lower end of the magnetic rod sleeve loading unit 20. This state can be used in the scenario of magnetic bead transfer. After mixing is completed, the first substrate driving motor 11 can drive the first lifting substrate 13 to descend, reducing the distance between the first lifting substrate 13 and the second lifting substrate 23. The magnetic field in the magnetic rod sleeve, especially in the bottom area of the magnetic rod sleeve, connected to the lower part of the magnetic rod sleeve loading unit 20 is enhanced, enabling it to adsorb magnetic beads. After adsorption, the second lifting substrate 23 can be driven to rise, thereby driving the first lifting substrate 13 to rise synchronously, and keeping the magnetic beads adsorbed while rising under the premise that the magnetic field around the magnetic rod sleeve remains unchanged.

[0058] Figure 9 It is a structural schematic diagram of the lateral movement driving structure; here, the upper half structure is removed, and only the lower half lateral movement driving and the cassette loading position 50 driving structure are shown. The lateral driving motor 51 is arranged in a horizontal lying manner and can be connected to the bottom plate of the extraction module through a fixed base. The output shaft of the lateral driving motor 51 is connected to the lateral lead screw 52. A lateral connecting block 53 is threadedly engaged with the lateral lead screw 52. The bottom end of the lateral connecting block is fixedly connected to the lateral slider 602, and the top end is connected to the vertical substrate 60. Among them, the lateral slider 602 is also fittedly connected to the lateral slide rail 603 arranged parallel to the lateral lead screw 52. When the lateral driving motor 51 drives the lateral lead screw 52 to rotate, the lateral connecting block 53 can be driven to slide along the extension direction of the lateral slide rail 603 to cooperate with the transfer between different holes of the extraction kit 30 to perform operations such as lysis, washing, and elution. The transmission method of the lead screw and slider can also make the lateral movement more accurate to meet the requirements of the extraction scenario; a loading driving motor 41 is also configured on the bottom plate of the extraction module. Here, in order to configure the loading driving mechanism in a limited space, the loading driving motor 41 is also assembled in an inverted manner. Its output is connected to the loading transmission gear 42. A module door 502 is elastically connected to the bottom plate of the extraction module and can latch the module door 502 with the side wall of the housing 100 of the extraction module by relying on the elastic force.

[0059] Figure 10It is a structural diagram of the cartridge loading position 50; the cartridge loading position 50 includes a loading platform that can be driven to move. A loading transmission rack 43 is arranged on one side wall of the loading platform, and a cartridge limiting member 505 is arranged at the top of the loading platform. It can accurately and reliably limit the extraction reagent cartridge 30 transferred onto it within the range of the cartridge limiting member 505. In order to achieve higher extraction efficiency, a lysis heating member 503 and an elution heating member 504 are also arranged within the range of the cartridge limiting member 505. The lysis holes and elution holes of the extraction reagent cartridge 30 can be in contact with the corresponding heating members, so that the liquid inside can be heated to the optimal operating temperature, ensuring that the extraction process can be carried out efficiently and thoroughly.

[0060] Figure 11 It is a process diagram of the cartridge loading position 50 being driven to extend beyond the main body range of the extraction module. Figure 12 It is a process diagram of the cartridge loading position 50 receiving the extraction reagent cartridge 30. Figure 13 It is a process diagram of the cartridge loading position 50 being driven to retract into the main body range of the extraction module. The entire process requires the loading drive motor 41 to drive the loading transmission gear 42 to rotate. The loading transmission rack 43 meshing with the loading transmission gear 42 can drive the connected loading platform to extend beyond the main body range of the extraction module. During the movement, the module compartment door elastically buckled on the extraction module can be pushed open by the loading platform, and the rollers 501 at the bottom of the loading platform can slide on the module compartment door 502 with low resistance. The out-of-module cartridge loading position 50 can cooperate with an automatic gripper to grip the extraction reagent cartridge 30, place it within the range limited by the cartridge limiting member 505, and make the lysis heating member 503 fit the lysis holes of the extraction reagent cartridge 30, and the elution heating member 504 fit the elution holes of the extraction reagent cartridge 30. Then the loading drive motor 41 rotates in the opposite direction to before, driving the loading platform to retract into the extraction module. After the action force of the loading platform disappears, the module compartment door 502 can be buckled on the receiving opening on the outer shell 100 under the action of the elastic force.

[0061] Figure 14 It is a process diagram of the magnetic rod sleeve loading unit 20 being driven to pick up and load the magnetic rod sleeve within the extraction reagent cartridge 30. Figure 15It is a process diagram of the magnetic rod sleeve loading unit 20 completing the loading of the magnetic rod sleeve; in this solution, the extraction kit 30 is also provided with a magnetic rod sleeve accommodation hole position, and multiple magnetic rod sleeves can be arranged side by side therein, so as to simplify the configuration of the extraction kit 30. The second substrate driving motor 21 can drive the second lifting substrate 23 to descend, and then drive the first lifting substrate 13 to descend synchronously, pick up the magnetic rod sleeve inside the magnetic rod sleeve accommodation hole, connect the magnetic rod sleeve to the end of the magnetic rod sleeve loading unit 20. After the magnetic rod sleeve is loaded, the second substrate driving motor 21 rotates in the reverse direction to synchronously lift the first lifting substrate 13 and the second lifting substrate 23. After the magnetic rod sleeve is loaded, the lateral driving motor 51 can drive the vertical substrate 60 to move laterally above the magnetic bead storage hole of the extraction kit 30. Then the second substrate driving motor 21 can lower to make the magnetic rod sleeve at least partially immersed in the magnetic bead storage liquid. The first substrate driving motor 11 can also rotate to lower the first lifting substrate 13, and the distance between the first lifting substrate 13 and the second lifting substrate 23 becomes smaller, and the magnetic rod unit 10 is more inserted into the magnetic rod sleeve, so that the bottom area of the magnetic rod sleeve has a strong magnetic field effect. Then the magnetic beads in the magnetic bead storage hole can be magnetically adsorbed on the outer wall surface of the bottom area of the magnetic rod sleeve. Then the magnetic beads are transferred to the lysis hole position of the extraction kit 30, and the transfer process is similar to the position change process after picking up the magnetic rod sleeve.

[0062] Figure 16 It is a diagram of the lysis state of the loaded magnetic rod sleeve in the lysis hole position of the extraction kit 30; after the magnetic beads are transferred into the lysis hole position of the extraction kit 30, the first substrate driving motor 11 can drive the first lifting substrate 13 to move upward along the vertical slide rail 601, and the distance between the first lifting substrate 13 and the second lifting substrate 23 becomes larger, and more parts of the magnetic rod unit 10 are withdrawn from the magnetic rod sleeve, so that the magnetic field in the bottom area of the magnetic rod sleeve becomes weak or even demagnetized. Then the rotation driving motor 31 can drive the magnetic rod sleeve to rotate, and the centrifugal force can be used to quickly and evenly disperse the previously adsorbed magnetic beads in the lysis hole position. Then, while maintaining a large distance between the first lifting substrate 13 and the second lifting substrate 23, the magnetic rod sleeve can be driven to perform rotational motion, lifting motion or lateral motion or a complex motion of any combination, and the lysis heating element 503 at the bottom can perform heating at a set temperature, so that an efficient and rapid lysis operation can be performed in the lysis hole position of the extraction kit 30.

[0063] Figure 17It is a diagram showing the elution state where the loaded magnetic rod is sleeved in the elution hole of the extraction kit 30; after lysis is completed, the magnetic rod unit 10 and the magnetic rod sleeve loading unit 20 cooperate to transfer the magnetic beads bound with nucleic acid fragments into the washing holes for washing operations. The number of washing holes can be 2 or 3 to perform more thorough washing and purification operations. After washing, the magnetic beads bound with nucleic acid fragments are adsorbed and collected by the wall surface of the magnetic rod sleeve and further transferred into the elution hole. To ensure that the nucleic acid bound to the magnetic beads is fully eluted, the elution process liquid includes a mixing operation step. In the mixing step, the bottom area of the magnetic rod sleeve is in a weak magnetic or demagnetized state, and the magnetic rod sleeve performs complex movements such as rotational movement, lifting movement, or a combination of both to fully mix. The elution heating element 504 can output a preset heating temperature to make the elution process more efficiently executed. Here, the liquid in the elution hole can be heated to a temperature greater than room temperature and not exceeding 65°C. Optimally, the temperature range is 30 - 65°C to ensure the elution efficiency and the qualified fragment length. After elution is completed, the magnetic rod unit 10 can be more inserted into the magnetic rod sleeve, making the outer wall surface of the bottom area of the magnetic rod sleeve have strong magnetic properties, adsorbing and collecting the used magnetic beads, and finally recycling them back to the previous magnetic bead storage hole.

[0064] Figure 18 It is an overall diagram of the extraction module configured in the housing 100. The entire extraction module can be configured within the illustrated cubic space. The outside of the extraction module is configured with a housing 100 composed of thin shell parts. Here, non-metallic materials such as plastics or metallic materials such as steel can be used to form the thin shell parts. There is also a storage opening on one side of the housing 100, and a module compartment door 502 is elastically buckled and connected to the storage opening so that the extraction module can be in a closed state to reduce the possibility of contamination to the system containing it. More preferably, a fan assembly 70 is also configured on the top of the extraction module. The fan assembly 70 is configured such that its air suction port is at the top of the extraction module to form a top suction method, which is also beneficial for forming a rotational flow in a local area within the module. The end of its air outlet is also connected to a filter element 701. Here, the filter element can be a HEPA filter screen with a high-efficiency filtration grade, so that the air that may pose a contamination risk within the extraction module is efficiently filtered and then discharged, with a lower contamination risk.

[0065] In this article, specific embodiments are used to elaborate on the principles and implementation methods of the present invention. The descriptions of the above embodiments are only used to help understand the method of the present invention and its core idea. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and modifications can still be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0066] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0067] In the description of the present invention, it should also be noted that unless otherwise clearly specified and defined, the terms "set", "installed", "connected", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

Claims

1. A method for extracting nucleic acid from a sample solution using magnetic beads, characterized in that: The steps include: Magnetic bead transfer step: driving the magnetic rod unit to be inserted into the magnetic rod sleeve, so that the magnetic rod sleeve is in a magnetized state, adsorbing the magnetic beads through the magnetic rod sleeve in the magnetized state, and transferring the adsorbed magnetic beads to the target wells containing the target solution; Magnetic bead release step: driving the magnetic rod unit to be withdrawn from the magnetic rod sleeve, so that the magnetic rod sleeve is in a weakly magnetized or demagnetized state, and driving the magnetic rod sleeve to rotate at the same time. The movement of the magnetic rod unit withdrawing from the magnetic rod sleeve and the rotation movement of the magnetic rod sleeve are driven simultaneously, which can cooperate with the gradually weakening magnetic force and centrifugal force to make the magnetic beads obtain different centrifugal forces, so that the magnetic beads can be automatically and relatively evenly dispersed in the target solution, so that the magnetic beads on the magnetic rod sleeve are separated from the magnetic rod sleeve and released into the target solution; Magnetic bead mixing step: driving the magnetic rod sleeve to perform at least one of translation, lifting or rotation in the target hole position, so that the magnetic beads are mixed in the target solution and the target operation is performed.

2. The method for extracting nucleic acid from a sample solution using magnetic beads according to claim 1, wherein: In the magnetic bead releasing step, the magnetic rod cover can be driven to rotate at a first speed, and in the magnetic bead mixing step, the magnetic rod cover can be driven to rotate at a second speed. The first speed ranges from 2800 to 3200 r / min, and the second speed is 0.75 to 0.9 of the first speed.

3. The method for extracting nucleic acid from a sample solution using magnetic beads according to claim 2, wherein: Also includes Magnetic bead collection step: After the target operation is completed, the magnetic rod unit is driven to be reinserted into the magnetic rod sleeve, so that the magnetic rod sleeve is in a magnetized state, and the magnetic rod sleeve in the magnetized state is driven to move in the target hole position, so that the magnetic beads in the target solution are re-adsorbed on the magnetic rod sleeve, and the magnetic beads are collected and transferred to the next station through the magnetic rod sleeve in the magnetized state.

4. The method for extracting nucleic acid from a sample solution using magnetic beads according to claim 3, characterized in that: In the magnetic bead collection step, the magnetic rod sleeve is first driven to move to a position matching the top liquid surface of the target solution, and then the magnetic rod unit is driven to be reinserted into the magnetic rod sleeve, so that the magnetic rod sleeve is in a magnetized state. Thereafter, the magnetic rod sleeve in the magnetized state is driven to perform lateral movement at the target hole position. When the lateral movement reaches a maximum distance, the magnetic rod sleeve in the magnetized state is driven to descend to a preset depth and then fold back to perform reverse lateral movement. This process is repeated, so that the magnetic rod sleeve in the magnetized state forms an S-shaped collection path that circuits at least once. When the magnetic rod sleeve in the magnetized state descends to the lowest position of the target hole position, the magnetic rod sleeve is driven to ascend and fold back along the S-shaped collection path, so that the magnetic beads left behind are collected in the magnetic rod sleeve in the magnetized state.

5. The method for extracting nucleic acid from a sample solution using magnetic beads according to claim 4, characterized in that: During the magnetic bead collection step, the preset amplitude of the lateral movement is 2.5-4 times the average hydraulic diameter of the magnetic rod sleeve.

6. The method for extracting nucleic acid from a sample solution using magnetic beads according to claim 1, wherein: In the magnetic bead release step, the total distance that the magnetic rod unit is pulled away from the magnetic rod sleeve is a set value, which is 10-20 times the average hydraulic diameter of the magnetic rod sleeve.

7. The method for extracting nucleic acid from a sample solution using magnetic beads according to any one of claims 3 to 6, characterized in that: Extracting nucleic acid from the sample solution requires sequentially performing a lysis operation, a washing operation, and an elution operation, wherein the lysis operation, the washing operation, and the elution operation all require sequentially performing a magnetic bead transfer step, a magnetic bead release step, a magnetic bead mixing step, and a magnetic bead collection step; in the lysis operation, the target well position is the lysis well, and the target solution is the lysis buffer added to the sample solution; in the washing operation, the target well position is the washing well position, and the target solution is the washing buffer; In the elution operation, the target well position is the elution well position, and the target solution is the elution buffer.

8. A nucleic acid extraction module, which uses the method for extracting nucleic acid from a sample liquid using magnetic beads as claimed in any one of claims 1 to 6 to perform nucleic acid extraction, characterized in that: The invention comprises an extraction module body, characterized in that a first lifting base plate, a first base plate driving motor, a first base plate transmission screw rod, a second lifting base plate, a second base plate driving motor, a second base plate transmission screw rod, a vertical slide rail and a vertical base plate are arranged in the extraction module body, a magnetic rod unit is connected to the first lifting base plate, a magnetic rod sleeve loading unit is connected to the second lifting base plate, the magnetic rod sleeve loading unit is hollow and one end of the magnetic rod sleeve can be connected to the magnetic rod sleeve, the magnetic rod unit can pass through the magnetic rod sleeve loading unit and extend into the magnetic rod sleeve; the vertical slide rail is connected to the vertical base plate, the first lifting base plate and the second lifting base plate are movably connected to the vertical slide rail through sliders respectively, and the first lifting base plate The plate is always configured at a higher position relative to the second lifting plate; the first substrate driving motor is assembled on the second lifting plate and is connected to the first lifting plate through the first substrate transmission screw rod; the first substrate driving motor can drive the first lifting plate to move relative to the second lifting plate along the vertical slide rail to change the relative distance between the first lifting plate and the second lifting plate; the second substrate driving motor is assembled on the vertical substrate and is connected to the second lifting plate through the second substrate transmission screw rod; the second substrate driving motor can drive the first lifting plate and the second lifting plate to move synchronously along the vertical slide rail; the first substrate transmission screw rod and the second substrate transmission screw rod are arranged in an opposite manner.

9. The nucleic acid extraction module according to claim 8, characterized in that The extraction module body also includes a transverse driving mechanism, which is connected to the vertical substrate and can drive the vertical substrate to move in the horizontal direction. The transverse driving mechanism includes a transverse driving motor, a transverse screw rod, a transverse slide rail, a transverse connecting block and a transverse slider. The transverse driving motor is connected to the transverse screw rod, and the transverse screw rod is threadedly connected with a transverse connecting block. The bottom end of the transverse connecting block is connected to the transverse slider and the top end is connected to the vertical substrate. The transverse slider is connected to a transverse slide rail arranged parallel to the transverse screw rod. The transverse slider can move along the extension direction of the transverse slide rail under the drive of the transverse driving motor.

10. The nucleic acid extraction module according to claim 8, characterized in that: The second lifting base plate is also provided with a rotation driving mechanism, which includes a rotation driving motor, a rotation driving gear, an intermediate gear and a rotation transmission gear. The rotation transmission gear is arranged at the end of the magnetic rod sleeve loading unit. Several magnetic rod sleeve loading units are arranged side by side, and the rotation transmission gears corresponding to adjacent magnetic rod sleeve loading units are meshed and transmitted in pairs. The rotation driving gear is meshed and connected with the intermediate gear, and the intermediate gear is meshed and connected with any rotation transmission gear. The rotary drive motor can drive the magnetic rod sleeve to rotate at a first speed and a second speed respectively. The first speed ranges from 2800 to 3200 r / min, and the second speed ranges from 0.75 to 0.9 of the first speed.

Images