CN109706056B

CN109706056B - Nucleic acid extraction device

Info

Publication number: CN109706056B
Application number: CN201910152648.3A
Authority: CN
Inventors: 王青; 厉刚
Original assignee: Beijing Junlikang Technology Development Co ltd
Current assignee: Beijing Junlikang Technology Development Co ltd
Priority date: 2019-01-14
Filing date: 2019-02-28
Publication date: 2024-02-27
Anticipated expiration: 2039-02-28
Also published as: CN109706056A

Abstract

The utility model relates to the technical field of nucleic acid extraction, and discloses a nucleic acid extraction device, which comprises: the device comprises a body, a first connecting rod and a second connecting rod, wherein the body is provided with an inner cavity and an inlet end and an outlet end which are communicated with the inner cavity; a filtering device is arranged at the outlet end; the inner cavity is filled with a porous nucleic acid adsorption medium, and the diameter of the porous nucleic acid adsorption medium is larger than the pore diameter of the filter hole of the filter device. According to the nucleic acid extraction device, the nucleic acid solution is adsorbed and extracted by the nucleic acid adsorption medium made of the porous material, the adsorption surface of the porous medium can be increased, the nucleic acid extraction efficiency is improved, the device is particularly suitable for high-precision detection of complex samples such as feces, sludge or soil, meanwhile, the device does not need to be matched with complex equipment such as a centrifuge, and the device is simple in structure, convenient and rapid, and suitable for on-site portable nucleic acid rapid extraction.

Description

Nucleic acid extraction device

Technical Field

The utility model relates to the technical field of nucleic acid extraction, in particular to a nucleic acid extraction device.

Background

In general, nucleic acid is extracted by first disrupting a biological sample material such as a cell or tissue material, inactivating nucleases, releasing nucleic acid, and then removing other tissues or cellular components such as proteins, polysaccharides, lipids, etc., thereby obtaining high-quality nucleic acid. In extracting nucleic acid from complex samples such as feces, sludge, or soil, it is also necessary to perform filtration or purification prior to the disruption treatment in order to remove particulate impurities in the feces, sludge, or soil. However, complicated equipment such as a centrifuge is required for the extraction process.

In recent years, with the advent of solid phase adsorption technology and the development of biochemistry, nucleic acid extraction has been greatly facilitated. However, portable rapid nucleic acid extraction methods suitable for use in the field remain a bottleneck in the current field of nucleic acid extraction.

The solid phase extraction technology mainly utilizes the interaction of static electricity, affinity, ion exchange or hydrogen bond between a solid phase adsorbent and nucleic acid, and the like, thereby achieving the purpose of separating the nucleic acid. Compared with the traditional extraction method, the solid phase extraction technology has the advantages of high speed and high efficiency, and can overcome the defect of incomplete separation of the organic phase and the water phase in the liquid phase extraction. Currently, solid phase extraction can be classified into non-magnetic solid phase extraction and magnetic separation extraction.

The non-magnetic solid phase extraction of nucleic acid is mainly performed in a centrifugal column chromatography mode, and the purpose of separating and adsorbing nucleic acid is achieved through centrifugal action. The solid phase extraction process is generally divided into four steps of cleavage, binding, washing and elution, and compared with the traditional method, the method can greatly shorten the extraction time of nucleic acid. A number of nucleic acid extraction kits are now developed based on this approach. The disadvantage of this method is that it must be carried out with the aid of centrifuges, and when a large number of samples are handled, cross-contamination cannot be avoided, which is prone to false positive results.

Magnetic particles for nucleic acid isolation in magnetic separation and extraction of nucleic acids are required to have both properties of superparamagnetism and surface functional groups. Firstly, superparamagnetism ensures that aggregation and dispersion of magnetic particles can be controlled by an externally applied magnetic field: secondly, functional groups on the surfaces of the magnetic particles react with nucleic acid molecules under certain conditions to enrich the nucleic acid. The nucleic acid extraction using magnetic particles mainly comprises three processes: 1. binding the nucleic acid molecule to the magnetic particle to form a magnetic particle-nucleic acid complex; 2. separating the magnetic particle-nucleic acid complexes under the action of an externally applied magnetic field; 3. eluting nucleic acid. Furthermore, a solution environment is required in which the magnetic particles bind to and separate from the nucleic acid molecules. For example, fe3O4 magnetic nanoparticles can enrich DNA in cell lysates under PEG-6000 and sodium chloride conditions. Magnetic particles currently in use include, for example, silica-coated magnetic particles, carboxylated magnetic nanoparticles, gelatin-coated magnetic nanoparticles, methacrylic acid-modified magnetic nanoparticles, etc., which are used to extract DNA, RNA, respectively, in corn, milk, bacteria, or viruses. The method has high technical cost, and the related kit on the market has high price, and is suitable for clinical detection because the extracted nucleic acid is relatively pure, but is mostly aimed at trace samples, and the total amount of the extracted nucleic acid is relatively small.

A variety of convenient and practical nucleic acid extraction devices are presently disclosed in the art, but these devices either require cooperation with other complex equipment (e.g., centrifuges) or require improvement in extraction efficiency. Efficient extraction of nucleic acids, or in particular high-precision detection of complex samples, etc., is still inadequate.

Disclosure of Invention

First, the technical problem to be solved

The utility model aims to solve the technical problems that a nucleic acid extraction device in the prior art is required to be matched with complex equipment such as a centrifugal machine and the like, and the extraction efficiency is low.

(II) technical scheme

In order to solve the technical problems in the prior art, the present utility model provides a nucleic acid extraction apparatus, comprising: the device comprises a body, a first connecting rod and a second connecting rod, wherein the body is provided with an inner cavity and an inlet end and an outlet end which are communicated with the inner cavity; a filtering device is arranged at the outlet end; the inner cavity is filled with a porous nucleic acid adsorption medium, and the diameter of the porous nucleic acid adsorption medium is larger than the pore diameter of the filter hole of the filter device.

Further, the porous nucleic acid adsorption medium is one or a mixture of a plurality of porous glass beads, rare earth material particles, graphene particles, porous silicon, porous ceramic particles and porous polysaccharide particles.

Further, the inner cavity of the body is also preloaded with a salt solution for assisting in nucleic acid extraction and cleavage.

Further, the body is an elastomer.

Further, the method further comprises the following steps: an inlet cover removably mounted to the inlet end and an outlet cover removably mounted to the outlet end.

Further, the method further comprises the following steps: a stirring device; the stirring device comprises: the stirring component is arranged in the inner cavity of the body, the rotary driving component is arranged outside the body, and the transmission component is used for transmitting the driving force of the rotary driving component to drive the stirring component to rotate; the transmission part is arranged in the mounting hole of the inlet cover so as to connect the stirring part and the rotary driving part.

Further, the transmission member includes: driven shafts and bearings; the driven shaft is rotatably arranged in the mounting hole through a bearing; one end of the driven shaft is connected with the driving shaft of the rotary driving part, and the other end of the driven shaft is connected with the stirring part.

Further, the rotational drive component includes, but is not limited to, a micro-drive motor, a spring leaf, or a spring wire.

Further, the outlet cover includes: the control valve includes a first state in which the first outlet and the second outlet are closed, a second state in which the first outlet is closed and the second outlet is opened, and a third state in which the first outlet is opened and the second outlet is closed.

Further, the outlet cover includes: a valve hole, in which the control valve is disposed;

further, the control valve includes: a first flow port and a second flow port, the control valve being relatively movable within the valve bore such that the control valve has the first, second and third states, the first state being such that the first flow port is moved to a position in which the first outlet is open and the second flow port is moved to a position in which the second outlet is closed; the second state is where the first flow port moves to a position where the first outlet is closed and the second flow port moves to a position where the second outlet is open; the third state is where the first flow port moves to a position where the first outlet is closed and the second flow port moves to a position where the second outlet is closed.

Further, the control valve further includes: the device comprises a first limiting part, a second limiting part, a third limiting part, a limiting piece and an elastic element; the limiting piece and the elastic element are respectively embedded in the outlet cover, and the limiting piece is arranged at the end part of the elastic element and pushed to the first limiting part, the second limiting part and the third limiting part by the elastic element, so that the limiting piece is in corresponding clamping with one of the first state, the second state and the third state.

(III) beneficial effects

According to the nucleic acid extraction device provided by the embodiment of the utility model, the nucleic acid solution is adsorbed and extracted by the nucleic acid adsorption medium made of the porous material, the adsorption surface of the porous medium can be increased, the nucleic acid extraction efficiency is improved, the device is especially suitable for high-precision detection of complex samples such as feces, sludge or soil, and meanwhile, the device does not need to be matched with complex equipment such as a centrifuge, and the device is simple in structure, convenient and rapid, and suitable for on-site portable nucleic acid rapid extraction.

Drawings

FIG. 1 is a schematic diagram showing the overall structure of an embodiment of a nucleic acid isolation apparatus according to the present utility model;

FIG. 2 is a schematic diagram showing the overall structure of another embodiment of the nucleic acid isolation apparatus of the present utility model.

FIG. 3 is a schematic diagram showing the overall structure of a nucleic acid isolation apparatus according to another embodiment of the present utility model.

FIG. 4 is a schematic view of an embodiment of the outlet cover of the present utility model in a third state;

FIG. 5 is a schematic view of an embodiment of an outlet cover in a first state;

FIG. 6 is a schematic structural view of an embodiment of the outlet cover of the present utility model in a second state;

fig. 7 is a schematic structural diagram of an embodiment of a receiving device of the present utility model.

Wherein:

the filter device comprises a body 1, an inlet end 1a, an outlet end 1b, a filter device 2, an inlet cover 3, an outlet cover 4, a stirring device 5, a sealing gasket 6, an inner cavity 11, a control valve 41, a first outlet 42, a second outlet 43, a valve hole 44, a stirring part 51, a rotary driving part 52, a transmission part 53, a first flow port 411, a second flow port 412, a first limiting part 413, a second limiting part 414, a third limiting part 415, a limiting part 416, an elastic element 417 and a receiving device 418.

Detailed Description

The following describes in further detail the embodiments of the present utility model with reference to the drawings and examples. The following examples are illustrative of the utility model and are not intended to limit the scope of the utility model.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

The term "nucleic acid" according to the utility model refers to the genetic material of an organism, which includes both deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). The term "nucleic acid extraction" as used herein refers to the process of isolating and purifying nucleic acids from a sample. The samples of the present utility model include both complex mixtures containing organisms and mixtures containing nucleic acid materials. Wherein the organism includes microorganisms, such as bacteria, viruses, etc., as well as tissues or cells of an animal subject (e.g., mammal, human). The "mixture" herein includes both a mixture containing a plurality of solvents and a mixture containing a plurality of solid components, and also includes a mixture containing both a solvent and a solid component. Examples of complex mixtures containing organisms include feces, sludge, and the like containing a variety of microorganisms, where nucleic acid extraction includes the process of separating organisms from complex mixtures and separating nucleic acids from organisms. Examples of the mixture containing nucleic acid substances include a cell lysate, a blood component (containing no cells), and the like, in which case nucleic acid extraction includes a process of separating nucleic acid substances from the mixture or also separating nucleic acids from a combination of proteins and nucleic acids.

FIG. 1 is a schematic diagram showing the structure of an embodiment of a nucleic acid isolation apparatus of the present utility model; FIG. 2 is a schematic diagram showing the structure of another embodiment of the nucleic acid isolation apparatus of the present utility model; FIG. 3 is a schematic diagram showing the structure of a nucleic acid isolation apparatus according to another embodiment of the present utility model. As shown in fig. 1-3. The nucleic acid extraction device comprises: a body 1, the body 1 having an inner cavity 11 and an inlet end 1a and an outlet end 1b communicating with the inner cavity 11; a filtering device 2 is arranged at the outlet end 1b; the inner cavity 11 is filled with a porous nucleic acid adsorption medium, and the diameter of the porous nucleic acid adsorption medium is larger than the pore diameter of the filter pores of the filter device 2.

Specifically, the body 1 is a main body part for nucleic acid extraction, and is a housing structure having an inner cavity 11, the shape of which includes, but is not limited to, a cylindrical shape (as shown in fig. 1), a funnel shape (as shown in fig. 2), a truncated cone shape (as shown in fig. 3), or a combination of various regular shapes, preferably a funnel shape. The body 1 may be made of a material which is extruded and which can be restored after releasing the pressure, such as an elastic material, and such a material can control the volume or pressure change in the internal cavity, and is beneficial to the discharge of the liquid in the internal cavity, so as to avoid the use of a centrifuge or a vacuum or a push rod plug to control the pressure change.

The inlet end 1a of the body 1 is one end of the housing, the outlet end 1b is the opposite end to the inlet end 1a, preferably the inlet end 1a is disposed at the top of the body 1, and the outlet end 1b is disposed at the bottom of the body 1. Opening the sealing cover of the inlet end 1a, adding a sample or sample solution of nucleic acid to be extracted into the inner cavity 11 from the inlet end 1a, covering the sealing cover to a sealing state, extracting in the cavity, and discharging the extracted waste liquid or nucleic acid extracting solution from the outlet end 1 b. The nucleic acid extraction process is carried out in the independently sealed body 1, so that various pollution phenomena possibly occurring are effectively reduced.

The inner cavity 11 of the body 1 is filled with a nucleic acid adsorption medium for adsorbing and separating nucleic acid in the liquid to be extracted, the volume of the nucleic acid adsorption medium is not more than 1/2 of the whole inner cavity 11, and the quantity of the nucleic acid adsorption medium can be determined according to actual needs. In order to enhance the adsorption binding force of nucleic acid and improve the extraction efficiency of nucleic acid, porous nucleic acid adsorption media can be adopted, the aperture of particles made of porous materials is preferably 1-20nm, the porous media can increase the adsorption surface area, the binding force of nucleic acid is enhanced, and particularly, the aperture with the aperture of 1-20nm is more suitable for the nucleic acid to enter the surface of the porous media. The diameter of the porous medium is an important factor affecting nucleic acid adsorption, and is not too large, but too large, the surface area becomes small, and the adsorption capacity is not too small, and the surface area becomes large, but the filtering device 2 is blocked, the filtering is affected, and the porous medium cannot be effectively separated from the particulate matters in the sample, and the diameter of the porous medium is typically between 1 and 1000 micrometers, preferably between 10 and 500 micrometers, more preferably between 30 and 300 micrometers, and more preferably between 50 and 200 micrometers.

The porous nucleic acid adsorption medium of this embodiment includes any one porous adsorption material or a mixed porous material of two or more porous adsorption materials selected from porous glass beads, rare earth material particles, graphene particles, porous silicon, porous ceramic particles, porous polysaccharide particles, and the like, and the outer surface of the porous nucleic acid adsorption medium has more hydroxyl groups or amino groups for enhancing the adsorption function of nucleic acid. Under the condition of micron-sized diameter meeting the conditions, different porous nucleic acid adsorption media have the same adsorption function on nucleic acid.

The porous glass beads are taken as an example for illustration, and the components of the porous glass beads comprise silicon dioxide, aluminum oxide, calcium oxide, magnesium oxide, sodium oxide, potassium oxide and the like. Wherein the content of silicon dioxide is 70-75wt%, the content of aluminum oxide is 1-2.5wt%, the content of calcium oxide is 8-10wt%, the content of magnesium oxide is 1.5-4.5wt%, and the sum of the content of sodium oxide and potassium oxide is 13-15wt%. The glass beads of the components have more hydroxyl or amino groups on the surfaces, which is more beneficial to the adsorption of nucleic acid substances.

Further preferably, the surface of the particulate matter of the present utility model is chemically modified to increase the surface hydroxyl content. For example, the surface of the particulate material may be chemically modified to hydroxylate using a piranha solution, which is a mixture of hot concentrated sulfuric acid and hydrogen peroxide, to remove all organics from the surface of the porous nucleic acid adsorbing medium while hydroxylating the surface of most of the material.

Further, a saline solution may be preloaded into the lumen 11 of the body 1. The salt solution is a salt solution known in the art, and has an auxiliary function of nucleic acid extraction and lysis, including but not limited to one or more of sodium iodide, guanidine isothiocyanate, sodium chloride and sodium chlorate. From the viewpoint of adsorption effect, sodium iodide and guanidine isothiocyanate are preferable as the salt solution. Both sodium iodide solution and guanidine isothiocyanate are very favorable for adsorption of nucleic acids. Sodium iodide solution is more preferable in view of safety and non-toxicity. Sodium chloride is preferred from the viewpoint of economy. The concentration of the salt solution is not particularly limited, but the concentration of the salt solution is not too low, and if too low, the adsorption effect of the nucleic acid is insufficient, and if too high, the cost increases and the adsorption effect of the nucleic acid is not significantly enhanced, usually between 2.5mol/L and 8mol/L, preferably 3 to 6mol/L, more preferably 3.5 to 5mol/L. The pH of the salt solution should not be too low, and impurities, particularly proteins and lipids, are easily deposited in the nucleic acid adsorption medium, which is detrimental to the adsorption of nucleic acids, nor too high, particularly preferably above the PKa value of the nucleic acid adsorption medium, which would result in a significant decrease in adsorption, typically the pH of the salt solution is 3-6, preferably 3.5-5, more preferably 4.

The filtering device 2 is used for filtering and removing particles and liquid components in the liquid, and can be arranged inside the outlet end 1b of the body 1 and close to or close to the outlet end 1b, wherein the pore diameter of the filtering hole is smaller than the diameter of the nucleic acid adsorption medium, and the nucleic acid adsorption medium is reserved in the inner cavity 11 of the body 1. However, the pore size of the filter pores is not too small and is easily blocked by particles in the liquid, and the pore size of the filter pores is usually larger than 1 micron, preferably larger than 5 microns, and more preferably larger than 10 microns. The filter device 2 is preferably one or a combination of more of nylon mesh, metal mesh, sand core, wherein the material of the sand core comprises glass, ceramic or a combination of both.

In this embodiment, the nucleic acid isolation apparatus according to the present utility model further includes: an inlet cover 3 detachably mounted at the inlet end 1a and an outlet cover 4 detachably mounted outside the outlet end 1 b. Specifically, the inlet cover 3 and the outlet cover 4 are both in cover-shaped structures, and are composed of a cover surface and an annular side surface fixed on the cover surface, the inlet cover 3 is in fit with the inlet end 1a, the outlet cover 4 is in fit with the outlet end 1b, and detachable connection can be performed in a threaded connection and buckle connection mode. The inlet cover 3 and the outlet cover 4 are preferably made of a hard material, preferably a hard plastic, such as ABS. The inlet cover 3 and the outlet cover 4 can seal the body 1 from the influence of the environment, wherein sealing gaskets 6 can be respectively arranged at the connection part of the inlet cover 3 and the inlet end 1a and the connection part of the outlet cover 4 and the outlet end 1b, and further sealing treatment can be carried out.

In this embodiment, the inlet cover 3 of the nucleic acid isolation apparatus of the present utility model is provided with a stirring device 5 through a mounting hole; the stirring device 5 includes: a stirring part 51 arranged in the inner cavity 11 of the body, a rotary driving part 52 arranged outside the body 1, and a transmission part 53 for transmitting the driving force of the rotary driving part 52 to drive the stirring part 51 to rotate; the transmission member 53 is installed in the installation hole of the inlet cover 3 to connect the stirring member 51 and the rotation driving member 52.

The transmission part 53 may be specifically composed of a driven shaft and a bearing, the driven shaft is rotatably installed in the installation hole of the inlet cover 3 through the bearing, one end of the driven shaft is connected with the driving shaft of the rotation driving part 52, and the other end is connected with the stirring part 51. In addition, other transmission structures, such as spring plates, springs, etc., can be used for the transmission member 53.

The rotary drive member 52 includes any one of a manual drive member, an automatic drive member, including but not limited to: any one type of driving component with automatic rotation function such as a rotary handle, a micro transmission motor, a spring piece, a spring wire and the like. The rotation driving member 52 moves the stirring member 51 in the cavity 11 of the body 1 to stir the liquid in the cavity 11, thereby promoting adsorption or desorption of the nucleic acid and the nucleic acid adsorbing medium.

The stirring member 51 is placed in the inner cavity 11 of the body 1 and moves in the inner cavity 11 to promote the flow of the liquid. The stirring member 51 may be rod-shaped as shown in fig. 2 and offset from the central axis of the cavity 11 of the body 1 by a certain distance; the stirring member 51 may be in the form of a blade as shown in fig. 3, and a plurality of blades may be uniformly disposed about the central axis of the inner cavity 11 of the body 1 and fixed to the free end of the stirring member 51 to promote mixing or flow of the liquid. The width of the vane is not more than 1/2 of the width of the internal cavity of the body 1 or 1/2 of the width of the internal cavity. The length of the stirring member 51 corresponds to the height of the body 1, and is preferably 70% to 90% of the height of the body 1.

Based on the above embodiments, in this embodiment, the outlet cover 4 may be an independent fully-closed outlet cover, or an outlet cover with a control valve and a liquid outlet function, where the independent fully-closed outlet cover has a sealing function in the present utility model, and when in use, a centrifuge tube with a corresponding volume is required to be equipped for auxiliary nucleic acid extraction according to the use procedure, and in this embodiment, the outlet cover with a control valve and a liquid outlet function is preferable (as shown in fig. 4).

Fig. 4 shows a schematic structural view of an embodiment of the outlet cover, and as shown in fig. 4, the outlet cover 4 includes: the control valve 41, the first outlet 42 and the second outlet 43, and the control valve 41 includes a first state in which the first outlet 42 and the second outlet 43 are closed, a second state in which the first outlet 42 is closed and the second outlet 43 is opened, and a third state in which the first outlet 42 is opened and the second outlet 43 is closed.

Specifically, the control valve 41 can be freely switched between the above three states as needed, thereby controlling the outflow of the liquid. According to the embodiment of the utility model, different fluids can conveniently flow out from different outlets by arranging the first outlet 42 and the second outlet 43, so that the pollution of a sample is avoided. Wherein the first outlet 42 and the second outlet 43 may have the same shape or may have different shapes, preferably different shapes, so as to facilitate distinguishing between the different outlets. In certain embodiments, the first outlet 42 of the present utility model is a waste outlet and the second outlet 43 is a nucleic acid extraction outlet. Referring to fig. 7, a receiving device 418 may be coupled below the first outlet 42 and the second outlet 43. The receiving means 418 may be a 1.5mLEP tube, the receiving means 418 being threadably connected to the first outlet 42 or the second outlet 43.

Further, the outlet cover 4 includes: a valve hole 44, wherein the control valve 41 is provided in the valve hole 44; the control valve 41 includes: a first flow port 411 and a second flow port 412, the control valve 41 being relatively movable within the valve bore 44, the control valve 41 having the first state, the second state, and the third state, the first state being where the first flow port 411 moves to open the first outlet 42, and the second flow port 412 moves to a position where the second outlet 43 is closed; the second state is that the first flow port 411 is moved to a position where the first outlet 42 is closed, and the second flow port 412 is moved to a position where the second outlet 43 is opened; the third state is that the first flow port 411 is moved to a position where the first outlet 42 is closed, and the second flow port 412 is moved to a position where the second outlet 43 is closed.

The control valve 41 is provided to penetrate the valve hole 44, and the control valve 41 is movable axially along the valve hole 44, and is switched among a left position, a middle position, and a right position. The control valve 41 includes a first flow port 411 and a second flow port 412, and the first flow port 411 and the second flow port 412 may be annular, or may be a through hole.

In fig. 4 the control valve 41 is in a third state, in which the first flow opening 411 is moved to a position where the first outlet 42 is closed and the second flow opening 412 is moved to a position where the second outlet 43 is closed. I.e. the situation where the cylindrical portion of the control valve 41 blocks both the first outlet 42 and the second outlet 43.

In fig. 5, the control valve 41 is in a first state, as shown in fig. 5, in which the first flow port 411 is moved to a position where the first outlet 42 is opened, and the second flow port 412 is moved to a position where the second outlet 43 is closed; that is, when the first flow passage 411 moves axially to the first outlet 42, the first outlet 42 is opened, and at the same time, the cylindrical portion of the control valve 41 is located at the second outlet 43, and the second outlet 43 is closed.

In fig. 6, the control valve 41 is in the second state, as shown in fig. 6, in which the first flow port 411 is moved to a position where the first outlet 42 is closed, and the second flow port 412 is moved to a position where the second outlet 43 is opened; that is, when the second flow-through port 412 moves to the second outlet 43, the second outlet 43 is opened, and at the same time, the cylindrical portion of the control valve 41 is located at the first outlet 42, and the first outlet 42 is closed.

In addition, referring to fig. 4, the control valve 41 further includes: a first limiting portion 413, a second limiting portion 414, a third limiting portion 415, a limiting member 416, and an elastic element 417; the limiting piece 416 and the elastic element 417 are respectively embedded in the outlet cover 4, and the limiting piece 416 is disposed at an end of the elastic element 417 and is pushed to the first limiting portion 413, the second limiting portion 414 and the third limiting portion 415 by the elastic element 417, so that the limiting piece 416 is in the first state, the second state and the third state and is correspondingly engaged with one of them. Specifically, in the present embodiment, the first limiting portion 413, the second limiting portion 414, and the third limiting portion 415 are annular grooves. The retainer 416 is preferably a steel ball and the resilient member 417 is preferably a coil spring.

As shown in fig. 4, the stopper 416 engages with the second stopper portion 414 located at the intermediate position, and the control valve 41 is in the third state. As shown in fig. 5, the stopper 416 engages with the third stopper 415 located at the rightmost end, and the control valve 41 is in the first state. As shown in fig. 6, the stopper 416 engages with the first stopper 413 located at the leftmost end, and the control valve 41 is in the second state. The axial push-pull control valve 41 can realize the switching between the states.

The foregoing description of the preferred embodiments of the utility model is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the utility model.

Claims

1. A nucleic acid extraction device, comprising: the device comprises a body, a first connecting rod and a second connecting rod, wherein the body is provided with an inner cavity and an inlet end and an outlet end which are communicated with the inner cavity; a filtering device is arranged at the outlet end; the inner cavity is filled with a porous nucleic acid adsorption medium, the diameter of the porous nucleic acid adsorption medium is larger than the pore diameter of the filter hole of the filter device,

the outlet cover is detachably connected with the outlet end in a threaded connection or snap connection mode;

the outlet cover includes: a control valve, a first outlet and a second outlet; and the control valve includes a first state in which the first outlet and the second outlet are closed, a second state in which the first outlet is closed and the second outlet is opened, and a third state in which the first outlet is opened and the second outlet is closed;

the outlet cover includes: a valve hole, in which the control valve is disposed;

the control valve includes: a first flow port and a second flow port, the control valve being relatively movable within the valve bore such that the control valve has the first, second and third states, the first state being such that the first flow port is moved to a position in which the first outlet is open and the second flow port is moved to a position in which the second outlet is closed; the second state is where the first flow port moves to a position where the first outlet is closed and the second flow port moves to a position where the second outlet is open; the third state is where the first flow port moves to a position where the first outlet is closed and the second flow port moves to a position where the second outlet is closed.

2. The nucleic acid extraction device of claim 1, wherein the porous nucleic acid adsorption medium is a mixture of one or more of porous glass beads, rare earth particles, graphene particles, porous silicon, porous ceramic particles, and porous polysaccharide particles.

3. The nucleic acid extraction device according to claim 1, wherein a salt solution for assisting in nucleic acid extraction and cleavage is further preloaded in the cavity of the body.

4. The nucleic acid isolation device of claim 1, wherein the body is an elastomer.

5. The nucleic acid extraction apparatus according to any one of claims 1 to 4, further comprising: an inlet cover removably mounted to the inlet end.

6. The nucleic acid extraction apparatus according to claim 5, further comprising: a stirring device; the stirring device comprises: the stirring component is arranged in the inner cavity of the body, the rotary driving component is arranged outside the body, and the transmission component is used for transmitting the driving force of the rotary driving component to drive the stirring component to rotate; the transmission part is arranged in the mounting hole of the inlet cover so as to connect the stirring part and the rotary driving part.

7. The nucleic acid extraction apparatus according to claim 6, wherein the transmission member includes: driven shafts and bearings; the driven shaft is rotatably arranged in the mounting hole through a bearing; one end of the driven shaft is connected with the driving shaft of the rotary driving part, and the other end of the driven shaft is connected with the stirring part.

8. The nucleic acid isolation device of claim 6, wherein the rotational drive component includes, but is not limited to, a micro-drive motor, a spring leaf, or a spring wire.

9. The nucleic acid extraction apparatus according to claim 1, wherein the control valve further comprises: the device comprises a first limiting part, a second limiting part, a third limiting part, a limiting piece and an elastic element; the limiting piece and the elastic element are respectively embedded in the outlet cover, and the limiting piece is arranged at the end part of the elastic element and pushed to the first limiting part, the second limiting part and the third limiting part by the elastic element, so that the limiting piece is in corresponding clamping with one of the first state, the second state and the third state.