CN113174310B

CN113174310B - Nucleic acid purification device

Info

Publication number: CN113174310B
Application number: CN202110057697.6A
Authority: CN
Inventors: 蔡亦梅; 张瑜; 滕明静; 范东雨; 李洁昆; 王宏伟; 任鲁风
Original assignee: Beijing Integrated Biosystems Co ltd
Current assignee: Beijing Integrated Biosystems Co ltd
Priority date: 2021-01-15
Filing date: 2021-01-15
Publication date: 2022-01-18
Anticipated expiration: 2041-01-15
Also published as: CN113174310A

Abstract

The invention relates to a nucleic acid purification device, which comprises an ultrasonic unit, a magnetic suction unit and a cleaning liquid pushing and sucking unit; the ultrasonic unit breaks up the magnetic beads in the purification bin, so that the nucleic acid in the mixture is adsorbed on the surfaces of the magnetic beads; the magnetic attraction unit fixes nucleic acid and magnetic beads at the purification bin; the cleaning liquid pushing and sucking unit cleans other impurities in the purification bin after the nucleic acid and the magnetic beads are fixed in the purification bin, so that the magnetic beads adsorbed with the nucleic acid are reserved in the purification bin. The nucleic acid purifying device has the advantages that the nucleic acid substances in the purifying bin are mixed through the ultrasonic unit, the nucleic acid substances and the magnetic beads are combined through chemical bonds and can be uniformly adsorbed on the magnetic beads in the purifying bin, the magnetic suction unit prevents the nucleic acid substances from being washed away in the cleaning process of the cleaning liquid pushing and sucking unit, and the cleaning liquid pushing and sucking unit automatically cleans the nucleic acid substances.

Description

Nucleic acid purification device

Technical Field

The invention relates to the field of biological detection, in particular to a nucleic acid purification device.

Background

The extraction, purification and amplification of nucleic acid are routine operations of nucleic acid detection experiments and are key steps in the process of gene analysis. In the gene analysis process, specific nucleic acid fragments are often required to be separated and extracted from a mixed sample for subsequent PCR amplification, so that the purification and recovery effects of nucleic acid directly influence the progress and the result of the whole gene analysis process.

The nucleic acid purification method is the most important factor influencing the quality of the extracted nucleic acid and is also the key of the success or failure of downstream molecular biology experiments. In almost every laboratory, separation and purification work related to biomolecules is very important and indispensable. However, it is difficult to purify a plurality of samples, because the integrity of nucleic acid molecules is maintained and the contamination of other molecules is eliminated as much as possible, not only a proper purification technology needs to be selected, but also the operation in the purification process needs to be performed with manpower, and the experimental process is monitored, so that the requirement of extracting and purifying high-throughput samples in the current rapid development is difficult to meet. There are many methods and instruments for purifying nucleic acids, and the principles employed and the equipment required are different.

Nucleic acid purification device among the correlation technique, the purification effect to nucleic acid needs further improvement, and the measuring accuracy is low, and simultaneously, the chip inner tube way does not integrate, and the reaction solution is difficult to mix and test as expected, and the extraction, purification, the amplification of nucleic acid need utilize different instruments to accomplish usually, complex operation.

Disclosure of Invention

Therefore, the invention provides a nucleic acid purification device, which can realize effective purification of nucleic acid, does not need manual intervention in the process, and is convenient and efficient.

In order to achieve the above object, the present invention provides a nucleic acid purification device, comprising an ultrasonic unit, a magnetic unit and a cleaning solution push-suction unit; the ultrasonic unit is used for scattering the magnetic beads in the purification bin, so that the nucleic acid in the mixture is adsorbed on the surfaces of the magnetic beads; the magnetic attraction unit is used for fixing the nucleic acid and the magnetic beads at the purification bin; the cleaning solution pushing and sucking unit is used for cleaning other impurities in the purification bin after the nucleic acid and the magnetic beads are fixed in the purification bin, so that the magnetic beads adsorbed with the nucleic acid in the purification bin are also provided with an amplification bin in the pipeline layer, and a temperature control unit is also arranged below the amplification bin;

a standard reaction matrix R0(F0, L0, T0) is further arranged in a central control unit which is respectively connected with the ultrasonic unit, the magnetic attraction unit and the temperature control unit and used for controlling the real-time vibration frequency F of the ultrasonic unit, the real-time position L of the magnetic attraction unit and the real-time temperature T of the temperature control unit, wherein F0 represents the standard vibration frequency of the ultrasonic unit, L0 represents the standard position of the magnetic attraction unit, and T0 represents the standard temperature of the temperature control unit;

the central control unit controls the ultrasonic unit, the magnetic attraction unit and the temperature control unit according to the standard reaction matrix R0(F0, L0, T0);

a time matrix t (t1, t2, t3) is further arranged in the central control unit, wherein t1 represents the vibration time of the ultrasonic unit, t2 represents the time interval for starting the magnetic suction unit after the ultrasonic unit stops vibrating, and t3 represents the time interval for starting the temperature control unit after the magnetic suction unit stops working;

in the reaction process, if the real-time vibration frequency F of the ultrasonic unit is lower than the standard vibration frequency F0 of the ultrasonic unit, increasing the vibration time t11 of the ultrasonic unit, and updating the time matrix t1(t11, t2, t3) in the central control unit, wherein the vibration time t11 of the ultrasonic unit is t1(1+ F/F0);

if the real-time vibration frequency of the ultrasonic unit is higher than or equal to the standard vibration frequency F0 of the ultrasonic unit, maintaining the vibration time t1 of the ultrasonic unit and maintaining the time matrix t (t1, t2, t3) in the central control unit.

Further, the ultrasonic unit comprises a lower plate and an upper plate, a plurality of guide rails are arranged between the upper plate and the lower plate, and a spring is arranged on each guide rail to provide reaction force for the upper plate; the ultrasonic horn penetrates through the upper plate, the lower part of the ultrasonic horn is connected with an ultrasonic transducer, the ultrasonic transducer is arranged between the upper plate and the lower plate, and the ultrasonic horn vibrates up and down in the process of transmitting and changing the amplitude; the upper end of the ultrasonic amplitude transformer acts on the magnetic beads in the purification bin; the lower end of the ultrasonic amplitude transformer is provided with a connecting flange, the lower end of the connecting flange is provided with the ultrasonic transducer, a circle of mounting holes are formed in the connecting flange, the connecting flange is mounted on the lower side face of the upper plate through the mounting holes, a through hole is formed in the middle of the connecting flange and is used for the ultrasonic amplitude transformer to pass through, and the lower end of the ultrasonic amplitude transformer is connected with the ultrasonic transducer to generate amplitude variation.

Furthermore, the lower side plate is provided with a plurality of limiting rods, the upper plate is provided with a plurality of limiting holes matched with the limiting rods and used for enabling the limiting rods to pass through, and when the ultrasonic transducer and the ultrasonic amplitude transformer work, the ultrasonic transducer and the ultrasonic amplitude transformer move in the preset vertical direction through the limiting rods.

Further, the gag lever post includes first spacing section and the spacing section of second, the diameter of the spacing section of second with the diameter of first spacing section is the same, and the spacing section of second can be through spacing hole, first spacing section and spacing hole downside contact to it is spacing to the vibration.

Furthermore, the inside of the first limiting section is a hollow cavity, a telescopic cylinder is arranged in the hollow cavity, the upper end of the cylinder rod is connected with a second limiting section, and the second limiting section moves up and down under the driving of the telescopic cylinder to change the overall height of the limiting rod, so that the spring compression amount is different.

Further, the magnetic attraction unit comprises a magnet fixing frame, a magnetic block and a lead screw device, the magnetic block is arranged above the lead screw device, the lead screw device pushes the magnetic block to reciprocate on the magnet fixing frame, and the magnetic block is used for fixing magnetic beads and nucleic acids at the purification bin by utilizing the attraction relationship between the magnetic beads and the magnetic block in the purification bin when the magnetic block moves to the lower part of the purification bin.

Furthermore, the screw device is an electric lifting screw device, and the screw device is further connected with a driving motor for driving the electric lifting screw device to rotate so as to realize the lifting of the magnetic block on the screw device.

Further, the washing liquid pushes away inhales the unit and includes reagent pipe, piston rod and connecting piece, there is the washing liquid in the reagent pipe, be provided with in the reagent pipe the piston rod, the one end of piston rod is connected with the connecting piece, be provided with the recess on the connecting piece, the piston rod is arranged in the recess, be used for the rotation effect of connecting piece pushes down washing liquid to purification storehouse for the washing to material in the purification storehouse.

Furthermore, the piston rod driving device further comprises a driving motor, and the driving motor drives the piston rod to rotate.

Furthermore, a speed reduction device is further arranged on the driving motor and used for controlling the rotating speed of the driving motor.

Compared with the prior art, the nucleic acid purification device has the advantages that the nucleic acid substances in the purification bin are mixed through the ultrasonic unit, so that the mixing is sufficient, the nucleic acid and the magnetic beads are combined through chemical bonds and can be uniformly adsorbed on the magnetic beads in the purification bin, the magnetic suction unit is used for fixing the position of the nucleic acid in the purification bin in the cleaning process of the cleaning liquid pushing and sucking unit to prevent the nucleic acid substances from being washed away, and the cleaning liquid pushing and sucking unit realizes automatic liquid suction and liquid suction through the motor to realize automatic cleaning of the nucleic acid substances.

In particular, the embodiment of the invention can complete all extraction, purification and amplification reactions in one device, realize reaction continuity, ensure higher integration level of experimental equipment and higher experimental continuity, and realize extraction, purification and amplification on one pipeline layer.

Especially, be provided with telescopic cylinder in the first spacing section in the supersound unit, the upper end of cylinder pole is connected with the spacing section of second, and the spacing section of second up-and-down motion under telescopic cylinder's drive to change the holistic height of gag lever post, thereby adapt to different spring compression volume.

Drawings

FIG. 1 is a schematic diagram showing an exploded structure of a nucleic acid purification apparatus according to an embodiment of the present invention;

FIG. 2 is a front view of a nucleic acid purification apparatus according to an embodiment of the present invention;

FIG. 3 is a side view of a nucleic acid purification apparatus according to an embodiment of the present invention;

FIG. 4 is a rear view of a nucleic acid purification apparatus according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of an ultrasound unit in an embodiment of the present invention;

FIG. 6 is a schematic diagram of an exploded structure of an ultrasonic unit in an embodiment of the present invention;

FIG. 7 is a diagram illustrating a chip structure according to an embodiment of the present invention;

FIG. 8 is an exploded view of a chip structure in an embodiment of the invention;

FIG. 9 is a schematic structural diagram of a sample addition layer in an embodiment of the present invention.

Detailed Description

In order that the objects and advantages of the invention will be more clearly understood, the invention is further described below with reference to examples; it should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only for explaining the technical principle of the present invention, and do not limit the scope of the present invention.

It should be noted that in the description of the present invention, the terms of direction or positional relationship indicated by the terms "upper", "lower", "left", "right", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, which are only for convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

Furthermore, it should be noted that, in the description of the present invention, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Referring to fig. 1 to 4, a nucleic acid purification apparatus provided in an embodiment of the present invention includes a nucleic acid extraction mechanism 10, a nucleic acid purification mechanism, and a nucleic acid amplification reaction mechanism, wherein the nucleic acid extraction mechanism 10, the nucleic acid purification mechanism, and the nucleic acid amplification reaction mechanism are all disposed in a housing to protect the nucleic acid extraction mechanism 10, the nucleic acid purification mechanism, and the nucleic acid amplification reaction mechanism from damage.

Wherein, body acid draws mechanism 10 includes application of sample device and pipeline layer 101, and the application of sample device includes application of sample layer 3, connecting piece and motor, be provided with a plurality of groups of reagent pipes in the application of sample layer, the one end of reagent pipe is arranged in the recess of connecting piece, motor control the connecting piece rotates, and then drives reagent pipe realizes the liquid push imbibition. The upper side of the sample adding layer is provided with a sample adding hole 302 for adding a sample into the chip, the sample adding hole is connected with a first reagent tube, a second motor drives a second connecting piece to push a lysate in a second reagent tube into the pipeline layer, the sample and the lysate are mixed in the pipeline layer to complete the cracking of the sample, so that nucleic acid and protein in the sample are separated to obtain a mixture of the nucleic acid and the protein, further, in order to obtain nucleic acid with higher purity, the protein in the mixture needs to be removed, in the embodiment of the invention, the mixture is drained to a purification bin, the nucleic acid purification mechanism comprises an ultrasonic unit 90 and a magnetic absorption unit 80, the vibration of the ultrasonic unit 90 is used for scattering magnetic beads in the purification bin, so that the nucleic acid in the mixture is more fully contacted with the magnetic beads, and the nucleic acid is absorbed on the magnetic beads through the acting force between the nucleic acid and the chemical bonds of the magnetic beads, magnetic unit 80 is used for with nucleic acid and magnetic bead are fixed in purification storehouse department, and the washing liquid pushes away and inhales the unit and is used for nucleic acid with the magnetic bead is fixed behind the purification storehouse, and is right other impurity in the purification storehouse is washd, so that remain in the purification storehouse and adsorb nucleic acid the magnetic bead specifically is the motor corotation of first reagent union coupling, realizes that first reagent pipe is outwards inhaled, and the motor reversal of second reagent union coupling realizes that second reagent pipe inwards pushes away, and then pushes away the mixture to the purification storehouse in, the mixture contacts with the magnetic bead in the purification storehouse this moment the below on pipeline layer is provided with supersound unit 90 and magnetic unit 80, supersound unit 90 with magnetic unit 80 sets up side by side.

In practical application, in order to prevent the deadweight effect of the ultrasonic unit 90 and the magnetic unit 80, in the embodiment of the present invention, a protection frame 91 is further provided, and the protection frame 91 is used for protecting the ultrasonic unit 90 and the magnetic unit 80 during use, and can also fix the ultrasonic unit 90 and the magnetic unit 80 to prevent the ultrasonic unit 90 and the magnetic unit 80 from shifting during use. The vibration of the ultrasonic unit 90 is used for scattering the magnetic beads in the purification bin, so that the nucleic acid in the mixture is more fully contacted with the magnetic beads, and then the nucleic acid is adsorbed on the magnetic beads by utilizing the chemical bond effect between the nucleic acid and the magnetic beads, further, the mixture in the purification bin needs to be further processed, the protein and the like in the mixture are washed away, and the nucleic acid is retained. Before cleaning, the magnetic unit 80 comprises a magnet fixing frame, a magnet and a screw rod device, the magnet is arranged above the screw rod device, the screw rod device pushes the magnet to reciprocate on the magnet fixing frame, when the magnet moves to the lower part of the purification bin, the magnetic beads and the nucleic acids are tightly fixed at the purification bin by utilizing the attraction relationship between the magnetic beads and the magnet, at the moment, a third motor connected with a third reagent tube is utilized to inject cleaning liquid inwards into the purification bin, a first reagent tube or a second reagent tube is required to be matched with the third reagent tube, the corresponding motor rotates forwards to realize that the first reagent tube or the second reagent tube can be pumped outwards, so that impurities such as protein and the like are pumped out of the purification bin, waste liquid is stored in the sample adding hole or the second reagent port, in practical application, in order to clean the nucleic acids, the cleaning can be carried out for a plurality of times, and the specific process can be repeated, and will not be described in detail herein.

And finally, in order to separate the nucleic acid adsorbed on the magnetic beads from the magnetic beads, the fifth motor connected with the fifth reagent tube is utilized to inject eluent inwards to the purification bin, and the magnets are arranged at the uppermost end of the support and are in close contact with the purification bin in the cleaning and eluting processes. And (3) introducing the nucleic acid in the purification bin into the amplification bin under the action of a pump valve, and finally closing a double valve connected with the amplification bin to wait for amplification reaction. Then, the excitation light source 20 disposed in the excitation light source mechanism chamber of the upper case 40 is turned on, and the fixed-band excitation light generated by the excitation light source 20 is irradiated on the amplification chamber to perform an amplification reaction, wherein the nucleic acid amplification reaction mechanism includes the excitation light source 20 and a temperature control unit disposed below the pipeline layer amplification chamber to control the temperature during the amplification reaction. The motor assembly includes first motor, second motor, third motor, fourth motor and fifth motor, the motor assembly with magnet drive arrangement all is connected with motor control panel card electricity, and the control signal of supersound unit 90 and magnetism unit 80 is from first control integrated circuit board 81, and all control signal send all come from industrial control board 100, industrial control board 100 sets up in display module assembly 110, and display module assembly 110 sets up on the tip inclined plane of epitheca 40 for the progress of demonstration experiment and the experimental operation step that corresponds. The power supply device 120 is used for supplying power to the PCR reaction main body and the display module 110, and the power supply device 120 is disposed at one side of the PCR reaction main body. The nucleic acid purification device provided by the embodiment of the invention is provided with a power supply device, realizes ultra-long standby, is convenient to move, is not limited by regions, and can carry out PCR reaction under any environment.

According to the nucleic acid purification device provided by the embodiment of the invention, the processes of extraction, purification and amplification reaction of nucleic acid are integrated, and the motor is used for logic control, so that the extraction process of nucleic acid does not need manual intervention, the corresponding purification reaction can be carried out only by controlling the ultrasonic unit and the magnetic attraction unit in the process of nucleic acid purification, and the amplification reaction can be completed by controlling the motor and exciting light to work.

Specifically, as shown in fig. 5 and 6, the ultrasonic unit 90 includes a lower plate 3-1, an upper plate 2-1, a plurality of guide rails 6-1 disposed between the lower plate and the upper plate, a spring 4-1 sleeved on each of the guide rails 6-1 for providing a reaction force to the upper plate, and an ultrasonic horn 1-1, wherein the ultrasonic horn 1-1 penetrates through the upper plate 2-1, and the lower portion of the ultrasonic horn 1-1 is connected to an ultrasonic transducer 13-1 through a connecting flange 12-1, and the ultrasonic transducer is disposed between the upper plate and the lower plate for connecting to the ultrasonic transducer to change the amplitude of the transducer. The ultrasonic amplitude transformer vibrates up and down in the process of transmitting and changing the amplitude; the guide rail is used for limiting the moving direction of the spring when the spring is compressed, and ensuring good contact between the ultrasonic transducer and the ultrasonic chip and the effectiveness of ultrasonic energy transfer.

In the embodiment of the invention, the ultrasonic chip specifically refers to a purification bin of a pipeline layer. The lower plate 3-1 of this embodiment is provided with a first mounting hole 31-1 in the middle for the lower end of the ultrasonic horn to pass through or guide the ultrasonic horn. A plurality of first guide rail mounting holes 32-1 are arranged on the upper side surface of the lower plate 3-1, in the embodiment, four or six first guide rail mounting holes are arranged, the lower end of each guide rail 6-1 is mounted in each first guide rail mounting hole, and a spring 4-1 is sleeved on each guide rail 6-1; correspondingly, a plurality of corresponding second guide rail mounting holes 21-1 are formed in the upper plate 2-1 and are used for being connected with the guide rails 6-1, so that the guide rails can pass through, and the movement position of the spring is limited when the spring is compressed; the guide rail is used for limiting the direction of movement of the spring when the spring is compressed, and the good contact between the vibration head plane and the ultrasonic chip and the effectiveness of ultrasonic energy transfer are ensured.

The middle of the upper plate 2-1 of this embodiment is provided with a second mounting hole 22-1 for the upper end of the ultrasonic amplitude bar to pass through and for the ultrasonic amplitude bar to vibrate up and down to pass through. In the embodiment of the invention, the lower end of the ultrasonic amplitude rod 1-1 is provided with a connecting flange 12-1, the lower end of the connecting flange 12-1 is provided with an ultrasonic transducer 13-1, a circle of mounting holes are arranged on the connecting flange 12-1, and the connecting flange 12-1 is mounted on the lower side surface of the upper plate through the mounting holes. A through hole is arranged in the middle of the connecting flange 12-1 for the ultrasonic amplitude transformer 1-1 to pass through, and the lower end of the ultrasonic amplitude transformer 1-1 is connected with the ultrasonic transducer 13-1 to generate proper amplitude variation.

The ultrasonic transducer and the ultrasonic amplitude rod of the embodiment of the invention generate longitudinal and transverse amplitudes in the working process, the upper plate is driven to move for a certain amplitude along with the continuous change of the amplitude, and when the amplitude is large enough, if the limiting rod is still at the preset position, the up-and-down movement of the upper plate and the flange is stopped, so that the amplitude output action is stopped.

Therefore, the limiting position of the limiting rod 5-1 can be adjusted. The lower side plate of the embodiment is provided with a plurality of limiting rods 5-1, the upper plate is provided with a plurality of limiting holes matched with the limiting rods 5-1 and used for enabling the limiting rods to pass through, when the ultrasonic transducer and the ultrasonic amplitude transformer work, vertical amplitude is generated, the ultrasonic transducer and the ultrasonic amplitude transformer can move in a preset vertical direction through the limiting rods, and deviation is avoided; meanwhile, the embodiment adopts a combination mode of the limiting rod and the through hole, so that the deviation of the ultrasonic amplitude transformer in the radial direction, namely the transverse direction, can be avoided, and the limiting rod cannot penetrate through the limiting hole when the deviation in the transverse direction is generated. Ultrasonic energy transfer acts on the magnetic bead in the purification storehouse in to the purification storehouse, and the magnetic bead in with the purification storehouse produces small clearance under the effect of ultrasonic resonance between magnetic bead and the magnetic bead, and nucleic acid can adsorb on the surface of magnetic bead this moment, and under the vibration effect, the magnetic bead contactless in the purification storehouse is convenient for the absorption of nucleic acid for absorbent more even. The gag lever post includes first spacing section and the spacing section of second, the diameter of the spacing section of second with the diameter of first spacing section is the same, and the spacing section of second can be through spacing hole, first spacing section and spacing downthehole side contact to it is spacing to the vibration. Of course, those skilled in the art can understand that there are many ways of performing the limiting by using the limiting rod, and the limiting method is not limited to the embodiments mentioned in the embodiments of the present invention, and optionally, the diameter of the first limiting section is smaller than that of the first limiting section, a shoulder is formed at the joint of the first limiting section and the second limiting section, the second limiting section can pass through the limiting hole, the shoulder between the first limiting section and the second limiting section is in contact with the lower side surface of the limiting hole, the inside of the first limiting section is a hollow cavity, a telescopic cylinder is arranged in the hollow cavity, the upper end of the cylinder rod is connected with the second limiting section, and the second limiting section moves up and down under the driving of the telescopic cylinder to change the overall height of the limiting rod, so as to adapt to different spring compression amounts. Through the work of ultrasonic transducer and ultrasonic amplitude pole, in the vibration process about the upper plate, carry on spacingly through the gag lever post, after reaching utmost point position, the convex shoulder of first spacing section and the spacing section of second produces the contact with the upper plate to it is spacing to realize.

Specifically, the embodiment of the present invention further includes a housing, the nucleic acid extraction mechanism, the nucleic acid purification mechanism, and the nucleic acid amplification reaction mechanism are all disposed in the housing, the housing includes an upper housing 40, a lower housing 30, an upper cover 50, and a light source cover plate 60, the upper housing 40 is provided with an excitation light source chamber 42 and a chip mounting chamber 41, the excitation light source chamber 42 is used for placing the excitation light source, the chip mounting chamber 41 is used for placing the pipeline layer and the sample-adding layer, the ultrasonic unit 90 and the magnetic unit 80 are both disposed between the upper housing 50 and the lower housing 30, and the temperature control unit is disposed between the upper housing 50 and the lower housing; the light source cover plate 60 is used to cover the excitation light source chamber 42, and the upper cover 50 is used to cover the chip mounting chamber 41. The nucleic acid extraction mechanism 10, the nucleic acid purification mechanism and the nucleic acid amplification reaction mechanism are all arranged in the shell, so that the internal structure of the shell is effectively protected, in addition, in the experimental process, an excitation light source in the upper shell 40 can generate certain heat in the working process to influence the temperature of the excitation light source bin 42, and optionally, an air inlet fan 31 is arranged below the excitation light source bin 42 to release the heat in the excitation light source bin 42.

Specifically, nucleic acid extraction mechanism 10 includes application of sample layer 3 and pipeline layer 101, it is arranged in chip installation storehouse 41, still be provided with daylighting module control panel 11 and valve control panel 12 on nucleic acid extraction mechanism 10, daylighting module control panel 11 sets up the below at upper cover 50, the daylighting control panel is used for shining the nucleic acid material to the storehouse of amplifing with the excitation light, and the fluorescence that will amplify the storehouse in production passes through the glass mouth on upper cover 50 and transmits to image acquisition device, valve control panel 12 is used for the break-make of the valve on the control pipeline layer, and then the flow direction of the interior liquid of control pipeline layer upper liquid way. One section of the upper cover 50 is provided with a connecting lug, and the connecting lug is matched with the connecting hole on the upper shell 40 to realize the movable connection between the upper cover 50 and the upper shell 40. And the upper cover 50 and the upper shell 40 are clamped to fix the nucleic acid extracting mechanism 10 in the chip mounting bin 41.

Specifically, referring to fig. 7 and 8, the upper side of the sample adding layer 3 is provided with a sample adding hole 302 for adding a sample into the chip, and the sample injected into the chip undergoes nucleic acid extraction, purification, amplification, and reaction. The sample adding layer 3 and the pipeline layer 101 of the present embodiment are movably connected to the limiting frame 106 disposed at the side of the pipeline layer 101 through the clamping strip 304, correspondingly, the inner side of the limiting frame 106 is provided with the first clamping groove 107, and the first clamping groove 107 is connected to each other through the clamping strip 304 in a matching manner, so as to realize the switching and fixing of the relative positions of the sample adding layer 3 and the pipeline layer 101. The switching of relative position indicates the change of the relative distance of application of sample layer 3 and pipeline layer 101 exactly, application of sample layer 3 is by the process of first draw-in groove 107 switching second draw-in groove for the distance between application of sample layer 3 and pipeline layer 101 has become nearly, take out gasket 2 after, application of sample layer 3 and pipeline layer 101 communicate, specifically speaking, gasket 2's primary function is protection application of sample layer 3 and pipeline layer 101 do not communicate, take out the gasket during the use again, wherein, seal membrane 104 is pasted in the downside of pipeline layer 101, in order to realize sealed. The assembled sample adding layer 3, the gasket 2, the pipeline layer 101 and the sealing film 104 form a completely closed whole, and viruses in the sample cannot leak.

As shown in fig. 9, the lateral surface of the limiting frame 106 at the lower side of the first engaging groove 107 of this embodiment is further provided with a second engaging groove, the second engaging groove is located at the lower side of the first engaging groove 107, when the sample adding layer 3 is transported or stored, the first card slot 107 is connected with the sample adding layer 3, when the reagent reaction is carried out, the gasket 3 is drawn out, the sample adding layer 3 is pressed downwards, so that the sample adding layer 3 is connected with the second card slot, at the same time, the pricking pin disposed on the pipeline layer 101 punctures the reagent disposed in the sample addition layer 3, so that the reagent and the sample can be mixed and reacted, and the puncture needle is arranged on the pipeline layer 101, and in the practical application process, the pipeline layer 101 is provided with an upright post, the puncture needle is arranged at the circle center of the upright post, the upper end surface of the upright post is oval, and the end surface of the upright post is inclined, so that the puncture needle on the upright post can be conveniently matched with the tail end of the reagent tube, the reagent tube can be smoothly punctured, and the reagent can be filled. According to the detection chip for nucleic acid detection provided by the embodiment of the invention, the first clamping groove 107 and the second clamping groove are arranged, so that the sample adding layer 3 and the pipeline layer 101 can be pressed to generate relative position change after the gasket 2 is extracted, and meanwhile, the pricker punctures a reagent in the sample adding layer 3 to realize sample adding and make a sample and the reagent perform a series of reactions.

As shown in fig. 8, the lower side of the gasket 2 of the embodiment of the present invention is further provided with a slide rail 202, and correspondingly, the upper side of the pipeline layer 101 is provided with a slide groove 108, and the slide rail 202 is connected with the slide groove 108 in a matching manner, so as to realize the sliding connection between the gasket 2 and the pipeline layer 101. The slide groove 108 of the present embodiment is provided inside the stopper 106 on the pipe layer 101. The end of the gasket 2 is provided with a plurality of notches and protrusions arranged at intervals, wherein the slide rail 202 is arranged on the bottom surface of the outermost protrusion.

Referring to fig. 8, the sample application hole 302 of the present embodiment is provided with a sample application hole cover 303 for sealing. Still set up buckle structure at application of sample layer 3 and pipeline layer 101, be provided with first buckle 301 in one side of application of sample layer 3, the downside of first buckle 301 stretches out the end and stretches out application of sample layer 3's bottom is installing application of sample layer 3 and pipeline layer 101 cooperation back together, through first buckle 301 joint on the side of pipeline layer 101 to prevent application of sample layer 3 and pipeline layer 101 separation.

As shown in fig. 8, the pipeline layer 101 of the present embodiment is provided with two first single valves 102 for controlling the stopping or flowing of the liquid in the pipeline layer 101 during the reaction process; the pipeline layer 101 is further provided with a double valve 103 for cutting off a road for fluid in the pipeline or allowing the fluid to pass through, the double valve 103 is communicated with the amplification bin through the pipeline, and the double valve 103 is used for controlling two ends of the amplification bin to be closed or opened simultaneously so that a closed cavity is formed inside the amplification bin. In fig. 8, handles 201 are further provided on both sides of the gasket 2 to facilitate extraction of the detection chip for nucleic acid detection. In the embodiment of the invention, the amplification bin is arranged at the edge of the pipeline layer 101, and the amplification bin is of a semi-elliptical structure, so that not only can the reaction of the reaction reagent be realized, but also the convenient positioning and installation can be realized through the convex semi-elliptical structure when in use.

Continuing to refer to fig. 8, in the present embodiment, a row of pricker 105 is disposed on the pipeline layer 101, after the sample-adding layer 3 and the gasket 2 are clamped together, the handle 201 is operated to slide the gasket 2 along the sliding groove 108, when the gasket 2 is pulled out when the gasket slides to a position where the gasket cannot advance, the sample-adding layer 3 is pressed into the second clamping groove from the first clamping groove 107, so that the pricker 105 can prick a reagent tube in the sample-adding layer 3, and further the pricker 105 is communicated with a reagent in the sample-adding layer 3, and when a fluorescence sequence marked in the reagent is complementarily matched with a nucleic acid pricker at a corresponding position, a group of probe sequences with completely complementary sequences is obtained by determining a probe position with the strongest fluorescence intensity. A baffle is disposed outside the needle 105, and it acts as a stop and a positioning function when the sample injection layer 3 is matched with the pipeline layer 101.

Specifically, in the embodiment of the present invention, in the sample loading state, a plurality of sets of reagent tubes are disposed in the sample loading layer 3, the sample loading layer 3 is clamped with the first clamping groove 107 through the clamping strip 304 thereon, in the initial installation state, the sample loading layer 3 is matched with the pipeline layer 101 from top to bottom, and the reagent in the reagent tubes is isolated from the lancet through the gasket 2, so that the lancet and the reagent are prevented from being mixed due to vibration in the transportation process, the sample loading layer and the pipeline layer are protected from being disconnected, and puncturing is avoided. When needs are tested, outwards take gasket 2 out along spout 108, outwards take back along spout 108 for gasket 2 presses application of sample layer 3 downwards for card strip 304 and the second draw-in groove joint on application of sample layer 3, and at this moment, felting needle 105 on setting up on pipeline layer 101 mixes with application of sample layer 3's reagent, introduces reagent into pipeline layer 101 and tests.

Specifically, the gasket structure is arranged, so that the detection chip for detecting nucleic acid can be stored completely in the process of storing and transporting the reagent, and when the detection chip is used, the reagent can be introduced into the pipeline layer only by drawing out the gasket and pressing the sample adding layer downwards.

FIG. 9 is a schematic view of a sample-adding layer according to an embodiment of the present invention; in this embodiment, a sample loading chamber is located below the sample loading hole 302, the sample loading chamber can be connected to a reagent tube for loading a reagent or a sample, a reagent outlet 312 is located at the lower portion of the sample loading chamber, a sealing structure 313 is located between the reagent outlet 312 and the sample loading chamber for sealing, and when a reagent needs to be loaded, the spike 105 can puncture 313 to allow the reagent to enter the fluid pipeline along the reagent outlet 312. A pressurizing structure is arranged on one side of the sample adding bin and comprises a tube wall 305, a piston 308 is arranged in the tube wall 305, and the piston 308 moves towards the sample adding bin to push the reagent in the sample adding bin to flow out to a reagent outlet 312; of course, when the reagent is required to be withdrawn, the piston 308 may also withdraw the reagent or other waste liquid, and a sealing ring 311 is provided at the end of the piston rod of the piston 308 for sealing.

Continuing to refer to fig. 9, the piston rod of this embodiment is further provided with a nut 307, which is in threaded connection with the nut 307 to realize relative rotation, and correspondingly, an output structure, such as an air cylinder and an oil cylinder, is provided at one end of the piston rod, or connected to the piston rod by rotating the output structure, such as a motor and a lead screw, at this time, the piston rod rotates, and only the reagent needs to be pushed to flow out of the reagent outlet. Correspondingly, a guide sleeve 306 is sleeved outside the nut 307, and a corresponding shaft shoulder is arranged inside the pipe wall 305 to position and fix the guide sleeve 306; snap rings 314 are further provided at the outer sides of both ends of the guide sleeve 306 to catch the corresponding guide sleeve 306. A sheath 309 is also provided outside the guide sleeve 306 to protect the piston rod, the nut 307 and the guide sleeve 306. When reagent is injected into the pipeline layer 101, the piston moves toward the sample loading bin to increase the pressure therein, so as to push the reagent to flow toward the reagent outlet 312, thereby realizing reagent injection. With reference to fig. 6, in the embodiment of the present invention, a plurality of sets of reagent tubes are provided, and in the embodiment, five sets of reagent tubes are provided, and different or the same reagents are sequentially applied to the pipeline layer according to the experiment requirement, so that the use efficiency can be greatly improved.

As shown in fig. 9, a second buckle 310 is disposed below the sample adding layer 3, and the second buckle 310 is disposed on a side surface opposite to the first buckle 301 to prevent the sample adding layer 3 from sliding.

It can be seen that this embodiment is integrated at chip pipeline layer to complicated experimentation, can control the liquid trend to can improve work efficiency effectively.

As can be understood by those skilled in the art, the tube structure disposed on the tube layer is unable to perform related nucleic acid detection tests when the sample adding layer is not connected to the tube layer, so that it is necessary to perform nucleic acid extraction, purification and amplification reactions when the tube layer is in contact with the sample adding layer.

Specifically, the pipeline layer comprises a first sample inlet, a first reagent port, a second reagent port, a third reagent port, a fourth reagent port, a purification bin and an amplification bin, the first sample inlet and the first reagent port are connected through a first pipeline, a first single valve is arranged on the first pipeline, the purification bin comprises an inlet and an outlet, the first sample inlet and the inlet are connected through a second pipeline, the first reagent port and the outlet are connected through a third pipeline, and the second reagent port, the third reagent port and the fourth reagent port are all connected with the inlet through a fourth pipeline; the first end of the amplification bin is provided with a first part of the double valve, the second end of the amplification bin is provided with a second part of the double valve, the first part of the double valve is connected with another single valve through a fifth pipeline, the other single valve is connected with the outlet through a sixth pipeline, and the first part of the double valve and the second part of the double valve are opened and closed simultaneously.

Particularly, application of sample layer upside is provided with the application of sample hole for to the internal interpolation sample of pipeline, the below of application of sample hole is the application of sample storehouse that a plurality of intervals set up one side of application of sample storehouse still is provided with the pressurization structure, and it includes the pipe wall, is provided with the piston in the pipe wall is inside, the piston along pipe wall reciprocating motion promotes its interior reagent to export outflow or take out to the reagent. One end of the pressurizing structure is further connected with a motor set, the motor set comprises a connecting piece and a driving motor, the piston is arranged at the groove of the connecting piece, and the driving motor drives the connecting piece to rotate so as to drive the piston to move along the pipe wall in a reciprocating mode. The embodiment of the invention also provides a zero reset plate 13 which is used for controlling the motor in the motor set to carry out zero reset so as to more accurately control the motor to rotate, realize accurate control on the piston and control the dosage of the reagent. In order to further control the rotating speed of the driving motor, a speed reducing device is further arranged and used for controlling the rotating speed of the driving motor, and the rotating speed of the motor is accurately controlled in the actual conveying process.

Specifically, when reagent injection is performed on the pipeline layer, the piston moves towards the sample loading bin to increase the pressure in the sample loading bin so as to push the reagent to flow towards the reagent outlet, and the injection of the reagent is realized. In the embodiment of the invention, a plurality of groups of reagent tubes are arranged, in the embodiment, five groups of reagent tubes are arranged, and different or same reagents are sequentially applied to the pipeline layer according to experiment requirements, so that the use efficiency can be greatly improved. And utilize the motor unit to drive the connecting piece and realize the control to the piston, convenient high efficiency.

It can be seen that in the embodiment, a complex experimental process is integrated on a pipeline layer of a chip, and the trend of liquid can be controlled, so that the working efficiency can be effectively improved.

Specifically, the magnetic attraction unit 80 includes a bracket, a magnet, and a magnet driving device, wherein the magnet driving device drives the magnet to move on a guide rail on the bracket to a position below the purification bin. In the purification reaction process, in order to prevent nucleic acid from being cleaned by using a cleaning solution, the nucleic acid is cleaned after being adsorbed by the ultrasonic unit, at the moment, the magnet is driven by the magnet driving device to move to the lower part of the purification bin along the guide rail, and when the nucleic acid is required to be transferred to the amplification bin after the cleaning is finished, the magnet is far away from the purification bin, so that the subsequent transfer of the nucleic acid from the purification bin to the amplification bin is facilitated, and the continuity of the experiment is ensured.

Specifically, the temperature control unit 70 includes a heating unit and a heat dissipation unit, the heating unit is a semiconductor cooling plate, the heating unit and the heat dissipation unit are both disposed under the chip mounting bin 41 and are in contact with a chip to be mounted, the heat dissipation unit is configured to dissipate heat from an amplification bin in the chip, and the heating unit is configured to heat the amplification bin in the chip, so that the temperature in the amplification bin is within a preset temperature range; the heat dissipation unit is electrically connected with the control module, and the control module is used for controlling the working states of the heat dissipation unit and the heating unit.

Specifically, the system also comprises a central control unit, wherein the central control unit is respectively connected with the ultrasonic unit, the magnetic suction unit and the temperature control unit and is used for controlling the real-time vibration frequency F of the ultrasonic unit, the real-time position L of the magnetic suction unit and the real-time temperature T of the temperature control unit;

a standard reaction matrix R0(F0, L0 and T0) is arranged in the central control unit, wherein F0 represents the standard vibration frequency of the ultrasonic unit, L0 represents the standard position of the magnetic suction unit, and T0 represents the standard temperature of the temperature control unit;

Specifically, the continuous reaction apparatus for nucleic acid extraction, purification and amplification provided by the embodiment of the present invention includes a standard reaction matrix R0(F0, L0 and T0) and a time matrix T (T1, T2 and T3) disposed in a central control unit, where F0 represents a standard vibration frequency of the ultrasonic unit, L0 represents a standard position of the magnetic attraction unit, T0 represents a standard temperature of the temperature control unit, T1 represents a vibration time of the ultrasonic unit, T2 represents a time interval for activating the magnetic attraction unit after the ultrasonic unit stops vibrating, T3 represents a time interval for activating the temperature control unit after the magnetic attraction unit stops vibrating, the vibration time of the ultrasonic unit is controlled according to a real-time frequency of the ultrasonic unit, and if the real-time frequency F of the ultrasonic unit is lower than a standard vibration frequency F0 of the ultrasonic unit, the vibration time T11 of the ultrasonic unit is increased, the vibration time t11 of the ultrasonic unit is t1(1+ F/F0), the real-time vibration frequency and the standard vibration frequency of the ultrasonic unit are compared, and the vibration time of the ultrasonic unit is adjusted according to the comparison result, so that the magnetic beads and nucleic acid substances in the purification bin are fully contacted and adsorbed in the reaction process, and the adsorption effect is better.

Particularly, well accuse unit can set up on the mainboard, can also set up in other positions, as long as can realize with supersound unit, magnetism inhale the unit with the control by temperature change unit be connected can, be convenient for have more the real-time change of the data in the well accuse unit change the vibration time of supersound unit, and magnetism inhale the unit with the start-up time of control by temperature change unit practices thrift the test time, improves experimental efficiency.

In the reaction process, the central control unit controls the vibration frequency of the ultrasonic unit and adjusts the vibration time of the ultrasonic unit according to the relation between the real-time vibration frequency and the standard vibration frequency, if the vibration time of the ultrasonic unit is increased, the time interval for starting the magnetic attraction unit after the ultrasonic unit stops vibrating can be shortened, because the magnetic beads and the nucleic acid substances have better adsorption effect in the ultrasonic vibration process, when the magnetic attraction unit is started to attract the magnetic beads in the amplification bin, the magnetic unit can be started more quickly, the magnetic beads in the amplification bin are adsorbed by the magnet of the magnetic unit, to perform the cleaning process, and save the reaction time, specifically, the time interval for activating the magnetic attraction unit can be changed to t 21-t 2(1-F/F0), the time interval of the corresponding temperature control unit can also be adaptively shortened to t 31-t 3 (1-F/F0).

According to the continuous reaction device based on nucleic acid extraction, purification and amplification, provided by the embodiment of the invention, the vibration time of the ultrasonic unit is changed through the change of the vibration frequency of the ultrasonic unit, and the time interval for starting the magnetic suction unit and the temperature control unit is further controlled according to the vibration time of the ultrasonic unit, so that the experiment progress is accelerated, the time required by the experiment is greatly shortened, and the experiment efficiency is improved.

During the experiment, when the amplification reaction is performed, the heating unit of the temperature control unit 70 starts to perform the first preheating operation; after the chip to be detected is detected again, carrying out second preheating operation on the chip to be detected; heating a chip to be detected; after the chip to be detected reaches the preset detection position, continuously heating the chip to be detected to heat the chip to be detected to the preset reaction temperature; in the heating process, if the temperature of the chip to be detected exceeds a preset detection temperature, starting a heat dissipation unit to perform a first heat dissipation operation; when the chip to be detected reaches the preset detection position and is within the preset detection temperature range, the chip detection device acquires images of the chip to be detected so as to detect the chip. After the reaction is finished, the heat dissipation unit completely dissipates heat for the chip so as to rapidly replace the chip. Through heating unit and radiating element, guarantee to detect that the chip is in suitable temperature range at the amplification reaction in-process, prevent that the temperature from crossing excessively low or too high influence amplification reaction's progress, improve experimental efficiency, guarantee the continuity of experiment. The lower shell 30 is further provided with a heat dissipation hole 32 and a heat dissipation fan, and in the working process of the nucleic acid purification device, the air intake fan 31, the heat dissipation fan and the heat dissipation hole 32 are arranged below the excitation light source bin 42 to form a one-way heat dissipation channel in the nucleic acid purification device provided by the embodiment of the invention, so that the excitation light source generating heat and the amplification bin can be timely dissipated.

Specifically, the nucleic acid purification apparatus provided by the embodiment of the present invention preferably includes a first main board 130, a second main board 140 and a key board 150, wherein the first main board 130 is disposed in the lower casing 30, and a control circuit for the air intake fan 31 and the heat dissipation fan is disposed on the first main board, wherein the heat dissipation fan is disposed on two sidewalls of the lower casing 30, and the heat dissipation hole 30 is disposed below the heat dissipation fan. Through holes are formed in the first main board 130 and the second main board 140, and the temperature control unit 70 sequentially penetrates through the through holes in the second board card 140 and the first board card 130, so that the temperature control unit 70, the cooling fan and the cooling holes are close to each other, and heat dissipation is facilitated. The key board 150 is provided with a key for controlling a device corresponding to the key. In particular, the key may be used to control the power supply device 150.

Therefore, the chip detection operation can be rapidly and conveniently carried out by the embodiment. And, through setting up the control by temperature change unit in order to heat the chip, through the operating temperature of simulation chip to carry out the detection of chip, not only can improve the detection efficiency of chip, still greatly improved the accuracy when chip detects.

Specifically, in the experimental process, in order to clearly understand the current experimental stage, the experimental device further includes a display module 110 and an industrial control board 100, the industrial control board 100 is disposed in the display module 110, the display module 110 is used for displaying the working state, the industrial control board 100 is used for controlling the temperature control unit 70, the motor unit, the ultrasonic unit 90 and the magnetic unit 80, and the display module is disposed on the inclined surface of the upper case. The display module assembly shows the parameter in experimental stage and the experimentation for the experimenter knows the progress in the experimentation clearly, and according to the experimentation after experimental parameter and experimental result revise, industrial control board 100 connects the temperature control unit 70 the motor train the supersound unit 90 and unit 80 is inhaled to magnetism, and the work operational aspect of various equipment in the overall assurance experimentation makes the experimentation go on in order, and the experimentation is continuous and visual.

The pipeline layer is also provided with a stop valve for controlling the on-off of the corresponding pipeline in the pipeline layer, and the stop valve, the reagent pipe and the motor set are matched to realize the control of the cracking liquid, the cleaning liquid and the eluent in the pipeline layer so as to complete corresponding mixing, cleaning and elution. Control opening or closing of stop valve through the stop valve control panel, and then the break-make of control pipeline layer liquid way guarantees to realize drawing, purification and amplification at the pipeline layer, guarantees the continuity of whole experimentation, and is high-efficient swift.

The excitation light source is an LED lamp or an LD lamp. The LED lamp or the LD lamp has the advantages of short starting time, high brightness, low energy consumption, small volume, long service life, high safety, low cost and the like, and is widely applied to the field of illumination. And at present, the manufacturing technology of monochromatic high-efficiency LED lamps with various colors is mature and widely applied. The LED light source has low driving voltage (2-5V), small volume and stable output light intensity, and is convenient for miniaturization of an excitation light source device.

So far, the technical solutions of the present invention have been described in connection with the preferred embodiments shown in the drawings, but it is easily understood by those skilled in the art that the scope of the present invention is obviously not limited to these specific embodiments. Equivalent changes or substitutions of related technical features can be made by those skilled in the art without departing from the principle of the invention, and the technical scheme after the changes or substitutions can fall into the protection scope of the invention.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention; various modifications and alterations to this invention will become apparent to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A nucleic acid purification apparatus, comprising: the cleaning solution pushing and sucking unit is arranged above the pipeline layer and pushes or sucks cleaning solution from a liquid inlet arranged in the pipeline layer;

the ultrasonic unit is used for scattering the magnetic beads in the purification bin, so that the nucleic acid in the mixture is adsorbed on the surfaces of the magnetic beads; the magnetic attraction unit is used for fixing the nucleic acid and the magnetic beads at the purification bin; the cleaning solution pushing and sucking unit is used for cleaning impurities in the purification bin after the nucleic acid and the magnetic beads are fixed in the purification bin so as to keep the magnetic beads adsorbed with the nucleic acid in the purification bin;

an amplification bin is further arranged in the pipeline layer, and a temperature control unit is further arranged below the amplification bin;

in the reaction process, if the real-time vibration frequency F of the ultrasonic unit is lower than the standard vibration frequency F0 of the ultrasonic unit, increasing the vibration time t11 of the ultrasonic unit, updating the time matrix t1(t11, t21, t 31) in the central control unit, wherein the vibration time t11= t1(1+ F/F0), the time interval for starting the magnetic suction unit is changed to t21 ═ t2(1-F/F0), and the time interval of the corresponding temperature control unit is shortened to t31 ═ t3 (1-F/F0);

if the real-time vibration frequency of the ultrasonic unit is higher than or equal to the standard vibration frequency F0 of the ultrasonic unit, maintaining the vibration time t1 of the ultrasonic unit, and maintaining the time matrix t (t1, t2, t3) in the central control unit;

the ultrasonic unit comprises a lower plate and an upper plate, a plurality of guide rails are arranged between the upper plate and the lower plate, and a spring is arranged on each guide rail to provide reaction force for the upper plate;

the ultrasonic horn penetrates through the upper plate, the lower part of the ultrasonic horn is connected with an ultrasonic transducer, the ultrasonic transducer is arranged between the upper plate and the lower plate, and the ultrasonic horn vibrates up and down in the process of transmitting and changing the amplitude; the upper end of the ultrasonic amplitude transformer acts on the magnetic beads in the purification bin; the lower end of the ultrasonic amplitude transformer is provided with a connecting flange, the lower end of the connecting flange is provided with the ultrasonic transducer, a circle of mounting holes are formed in the connecting flange, the connecting flange is mounted on the lower side surface of the upper plate through the mounting holes, a through hole is formed in the middle of the connecting flange and is used for the ultrasonic amplitude transformer to pass through, and the lower end of the ultrasonic amplitude transformer is connected with the ultrasonic transducer to generate amplitude variation;

the lower side plate is provided with a plurality of limiting rods, the upper plate is provided with a plurality of limiting holes matched with the limiting rods and used for enabling the limiting rods to pass through, and when the ultrasonic transducer and the ultrasonic amplitude transformer work, the ultrasonic transducer and the ultrasonic amplitude transformer move in a preset vertical direction through the limiting rods;

the limiting rod comprises a first limiting section and a second limiting section, the diameter of the second limiting section is the same as that of the first limiting section, the second limiting section can pass through the limiting hole, and the first limiting section is in contact with the lower side surface of the limiting hole so as to limit vibration;

the inside of the first limiting section is a hollow cavity, a telescopic cylinder is arranged in the hollow cavity, the upper end of the cylinder rod is connected with a second limiting section, and the second limiting section moves up and down under the driving of the telescopic cylinder to change the overall height of the limiting rod, so that the spring compression amount is different.

2. The nucleic acid purification apparatus of claim 1, wherein the magnetic attraction unit comprises a magnet holder, a magnet block and a screw device, the magnet block is disposed above the screw device, the screw device pushes the magnet block to reciprocate on the magnet holder, and the magnet block is configured to fix the magnetic beads and the nucleic acids at the purification chamber by using an attraction relationship between the magnetic beads and the magnet block in the purification chamber when the magnet block moves to a position below the purification chamber.

3. The nucleic acid purification device according to claim 2, wherein the screw device is an electric lifting screw device, and the screw device is further connected with a driving motor for driving the electric lifting screw device to rotate so as to realize the lifting of the magnetic block on the screw device.

4. The nucleic acid purification device according to claim 1, wherein the cleaning solution pushing and sucking unit comprises a reagent tube, a piston rod and a connecting member, the cleaning solution is arranged in the reagent tube, the piston rod is arranged in the reagent tube, one end of the piston rod is connected with the connecting member, a groove is arranged on the connecting member, and the piston rod is arranged in the groove and used for pushing the cleaning solution into the purification bin under the rotating action of the connecting member so as to clean the substances in the purification bin.

5. The nucleic acid purification apparatus according to claim 4, further comprising a driving motor for rotating the piston rod.

6. The nucleic acid purification apparatus according to claim 5, wherein a speed reduction device is further provided on the driving motor, and the speed reduction device is configured to control a rotation speed of the driving motor.