Microfluidic chip, nucleic acid extraction method thereof and nucleic acid extraction device

Abstract

The microfluidic chip, nucleic acid extraction method and nucleic acid extraction device provided by the present disclosure include a channel plate layer, which includes: a liquid inlet groove, a mixing and lysis channel, a nucleic acid extraction channel, a first air pressure driving port and a second air pressure driving port. Among them, the liquid inlet groove, the mixing and lysis channel, the nucleic acid extraction channel and the first air pressure driving port are sequentially connected to form a liquid flow channel, and the liquid inlet groove, the mixing and lysis channel and the second air pressure driving port are sequentially connected to form another liquid flow channel; a cover plate layer, which is disposed opposite to the channel plate layer, and the cover plate layer includes a liquid inlet through hole corresponding to the liquid inlet groove; a solution storage cavity, which is located on the side of the cover plate layer away from the channel plate layer, and the solution storage cavity includes a liquid outlet through hole corresponding to the liquid inlet through hole.

Description

Technical Field

[0001] The present disclosure relates to the field of microfluidic technology, and in particular, to a microfluidic chip, a nucleic acid extraction method thereof, and a nucleic acid extraction device. Background Art

[0002] The technology of separating and purifying nucleic acids from samples and other biological macromolecules is the basis in the sample preparation process required for molecular detection, and belongs to the key technology in the fields of life science research applications and in vitro diagnosis. Traditional nucleic acid extraction methods mainly use the extraction method in centrifuge tubes. Whether it is manual or machine automatic, it will inevitably cause waste of space and reagents, thereby increasing costs. With the development and application of microfluidic technology, microfluidic technology can effectively reduce the sample volume, reduce costs, and has the advantage of portability, and has unique advantages in in vitro point-of-care diagnosis. Based on the microfluidic nucleic acid extraction method has been developed, but the general microfluidic nucleic acid extraction method only fixes substances that adsorb nucleic acids such as silica and diatoms on the inner wall of the channel, and then manually adds reagents and removes waste liquid. The method steps are cumbersome, time-consuming and laborious, resulting in poor extraction rate and repeatability of the results. In view of this, it is necessary to provide an integrated nucleic acid extraction chip based on microfluidic technology that is efficient, automatic, and easy to use. Summary of the Invention

[0003] The microfluidic chip, its nucleic acid extraction method, and nucleic acid extraction device provided by the embodiments of the present disclosure are as follows:

[0004] On the one hand, a microfluidic chip provided by an embodiment of the present disclosure includes:

[0005] A channel plate layer, the channel plate layer includes: a liquid inlet groove, a mixing and lysis channel, a nucleic acid extraction channel, a first air pressure driving port, and a second air pressure driving port. Among them, the liquid inlet groove, the mixing and lysis channel, the nucleic acid extraction channel, and the first air pressure driving port are sequentially connected to form a liquid flow channel, and the liquid inlet groove, the mixing and lysis channel, and the second air pressure driving port are sequentially connected to form another liquid flow channel;

[0006] A cover plate layer, which is disposed opposite to the channel plate layer, and the cover plate layer includes a liquid inlet through hole corresponding to the liquid inlet groove;

[0007] A solution storage cavity, located on the side of the cover plate layer away from the channel plate layer, and the solution storage cavity includes a liquid outlet through hole corresponding to the liquid inlet through hole.

[0008] Optionally, in the above microfluidic chip provided by the embodiment of the present disclosure, the solution storage cavity includes a magnetic bead buffer solution storage cavity, a binding solution storage cavity, a washing solution storage cavity, and an elution solution storage cavity;

[0009] The liquid inlet through-holes include a magnetic bead buffer liquid inlet through-hole, a binding liquid inlet through-hole, a washing liquid inlet through-hole, and an elution liquid inlet through-hole;

[0010] The liquid inlet grooves include: a magnetic bead buffer liquid inlet groove, a binding liquid inlet groove, a washing liquid inlet groove, and an elution liquid inlet groove;

[0011] Wherein, the magnetic bead buffer storage cavity, the magnetic bead buffer liquid inlet through-hole, and the magnetic bead buffer liquid inlet groove are sequentially communicated;

[0012] The binding liquid storage cavity, the binding liquid inlet through-hole, and the binding liquid inlet groove are sequentially communicated;

[0013] The washing liquid storage cavity, the washing liquid inlet through-hole, and the washing liquid inlet groove are sequentially communicated;

[0014] The elution liquid storage cavity, the elution liquid inlet through-hole, and the elution liquid inlet groove are sequentially communicated.

[0015] Optionally, in the above microfluidic chip provided by the embodiments of the present disclosure, the mixing and lysis channel includes a mixing and lysis groove, a first channel directly connecting the mixing and lysis groove and the magnetic bead buffer liquid inlet groove, a second channel directly connecting the mixing and lysis groove and the binding liquid inlet groove, a third channel directly connecting the mixing and lysis groove and the washing liquid inlet groove, a fourth channel directly connecting the mixing and lysis groove and the elution liquid inlet groove, a fifth channel indirectly connecting the mixing and lysis groove and the second pneumatic driving port, and a sixth channel directly connecting the mixing and lysis groove and the nucleic acid extraction channel.

[0016] Optionally, in the above microfluidic chip provided by the embodiments of the present disclosure, it further includes: a first valve for controlling whether the liquid in the first channel flows, a second valve for controlling whether the liquid in the second channel flows, a third valve for controlling whether the liquid in the third channel flows, a fourth valve for controlling whether the liquid in the fourth channel flows, a fifth valve for controlling whether the liquid in the fifth channel flows, and a sixth valve for controlling whether the liquid in the sixth channel flows.

[0017] Optionally, in the above microfluidic chip provided by the embodiments of the present disclosure, the fifth channel between the fifth valve and the second pneumatic driving port is zigzag.

[0018] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the zigzag-shaped fifth channel includes a first part and a second part that are cross-set and communicate with each other, wherein the first part is directly communicated with the fifth valve, the second part is indirectly communicated with the second pneumatic driving port, and the length of the first part is greater than the length of the second part.

[0019] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the included angle between the first part and the second part is 30° to 150°.

[0020] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, any one of the first valve, the second valve, the third valve, the fourth valve, the fifth valve, and the sixth valve includes: a first limiting through hole on the channel plate layer, a second limiting through hole correspondingly arranged on the cover plate layer with respect to the first limiting through hole, a valve core that moves between the first limiting through hole and the second limiting through hole, a bottom film that seals the first limiting through hole on the side of the channel plate layer facing away from the cover plate layer, and an elastic film that bears the valve core on the side of the cover plate layer facing the channel plate layer, and the elastic film covers the second limiting through hole.

[0021] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, any one of the first valve, the second valve, the third valve, the fourth valve, the fifth valve, and the sixth valve includes: a limiting groove on the channel plate layer, a second limiting through hole correspondingly arranged on the cover plate layer with respect to the limiting groove, a valve core that moves between the limiting groove and the second limiting through hole, and an elastic film that bears the valve core on the side of the cover plate layer facing the channel plate layer, and the elastic film covers the second limiting through hole.

[0022] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the channel plate layer includes a first channel layer, a first adhesive layer, and a second channel layer that are sequentially stacked, wherein the first channel layer is close to the cover plate layer;

[0023] The first channel layer includes a first mixing and lysis groove, a first sub-channel directly connecting the first valve and the magnetic bead buffer liquid inlet groove, a second sub-channel directly connecting the second valve and the binding liquid inlet groove, a third sub-channel directly connecting the third valve and the cleaning liquid inlet groove, and a fourth sub-channel directly connecting the fourth valve and the elution liquid inlet groove;

[0024] The first adhesive layer includes an independent second mixing and lysis groove and a first nucleic acid extraction channel;

[0025] The second channel layer includes a third mixed cracking groove, a second nucleic acid extraction channel, a fifth sub-channel directly connecting the first valve and the third mixed cracking groove, a sixth sub-channel directly connecting the second valve and the third mixed cracking groove, a seventh sub-channel directly connecting the third valve and the third mixed cracking groove, an eighth sub-channel directly connecting the fourth valve and the third mixed cracking groove, a ninth sub-channel directly connecting the third mixed cracking groove and the fifth valve, a tenth sub-channel indirectly connecting the fifth valve and the second pneumatic driving port, an eleventh sub-channel directly connecting the third mixed cracking groove and the sixth valve, and a twelfth sub-channel directly connecting the sixth valve and the second nucleic acid extraction channel;

[0026] Wherein, the first sub-channel and the fifth sub-channel constitute the first channel, the second sub-channel and the sixth sub-channel constitute the second channel, the third sub-channel and the seventh sub-channel constitute the third channel, the fourth sub-channel and the eighth sub-channel constitute the fourth channel, the ninth sub-channel and the tenth sub-channel constitute the fifth channel, and the eleventh sub-channel and the twelfth sub-channel constitute the sixth channel;

[0027] The first mixed cracking groove, the second mixed cracking groove, and the third mixed cracking groove are directly connected in sequence to form the mixed cracking groove, and the orthographic projection of the first mixed cracking groove on the plane where the cover layer is located, the orthographic projection of the second mixed cracking groove on the plane where the cover layer is located, and the orthographic projection of the third mixed cracking groove on the plane where the cover layer is located substantially coincide;

[0028] The first nucleic acid extraction channel and the second nucleic acid extraction channel are directly connected to form the nucleic acid extraction channel, and the orthographic projection of the first nucleic acid extraction channel on the plane where the cover layer is located substantially coincides with the orthographic projection of the second nucleic acid extraction channel on the plane where the cover layer is located.

[0029] Optionally, in the above microfluidic chip provided by the embodiments of the present disclosure, any one of the first valve, the second valve, the third valve, the fourth valve, the fifth valve, and the sixth valve includes: a first limiting through hole on the first channel layer, a diversion hole directly communicating with the first limiting through hole on the first glue layer, a second limiting through hole corresponding to the first limiting through hole on the cover layer, a valve core moving between the first limiting through hole and the second limiting through hole, and an elastic membrane carrying the valve core on the side of the cover layer facing the first channel layer, and the elastic membrane covers the second limiting through hole;

[0030] Among them, any one of the first valve, the second valve, the third valve, and the fourth valve is provided with one of the drainage holes, and any one of the fifth valve and the sixth valve is provided with two of the drainage holes.

[0031] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, it further includes: a first protective film that seals the second limiting through hole on the side of the cover layer facing away from the channel plate layer.

[0032] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the cover layer further includes an expansion groove surrounding the second limiting through hole, and the orthographic projection of the expansion groove on the plane where the cover layer is located overlaps with the orthographic projection of the elastic membrane on the plane where the cover layer is located.

[0033] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the expansion groove includes a first expansion groove and / or a second expansion groove, wherein the first expansion groove is located on the side of the cover layer facing away from the channel plate layer, the second expansion groove is located on the side of the cover layer facing the channel plate layer, the orthographic projection of the first expansion groove on the plane where the cover layer is located is substantially the same as the orthographic projection of the elastic membrane on the plane where the cover layer is located, and the orthographic projection of the second expansion groove on the plane where the cover layer is located is located within the orthographic projection of the elastic membrane on the plane where the cover layer is located.

[0034] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the distance between the boundary of the orthographic projection of the second expansion groove on the plane where the cover layer is located and the boundary of the orthographic projection of the elastic membrane on the plane where the cover layer is located is 0.5 mm to 1.0 mm.

[0035] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, in the vertical direction of the plane where the cover layer is located, the depth of the first expansion groove is 0.8 mm to 1.2 mm, and the depth of the second expansion groove is 11 μm to 50 μm.

[0036] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, it further includes a second adhesive layer that bonds the cover layer and the channel plate layer. The second adhesive layer includes a first through hole directly connecting the combined liquid inlet through hole and the magnetic bead buffer liquid inlet groove, a second through hole directly connecting the combined liquid inlet through hole and the combined liquid inlet groove, a third through hole directly connecting the cleaning liquid inlet through hole and the cleaning liquid inlet groove, a fourth through hole directly connecting the eluent inlet through hole and the eluent inlet groove, a housing hole for accommodating the elastic membrane, and a fifth through hole directly connecting the mixing and lysing groove.

[0037] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, magnetic beads are further included in the mixing and lysis groove.

[0038] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the mixing and lysis groove includes a reaction groove and a buffer groove that communicate with each other. Among them, the reaction groove is directly communicated with the first channel, the second channel, the third channel, the fourth channel, and the sixth channel respectively, and the buffer groove is directly communicated with the fifth channel.

[0039] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the mixing and lysis groove includes a reaction groove and a buffer groove that communicate with each other. Among them, the reaction groove is directly communicated with the first channel, the second channel, the third channel, and the fourth channel respectively, and the buffer groove is directly communicated with the fifth channel and the sixth channel respectively.

[0040] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the cover layer further includes an expansion through hole that completely covers the reaction groove, and a second protective film that seals the expansion through hole on the side of the cover layer facing away from the channel plate layer.

[0041] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the buffer groove is spindle-shaped.

[0042] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the width is the largest at the position of 1 / 2 to 3 / 4 in the extending direction of the spindle shape.

[0043] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the mixing and lysis groove further includes a diversion channel that directly communicates the mixing and lysis groove with the buffer groove, and the diversion channel is "S"-shaped.

[0044] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the channel plate layer further includes a waste liquid groove, and the waste liquid groove is directly communicated with the nucleic acid extraction channel, the fifth channel, and the second air pressure driving port respectively;

[0045] The cover layer further includes a waste liquid through hole corresponding to and communicating with the waste liquid groove;

[0046] The microfluidic chip further includes a waste liquid cavity embedded in the waste liquid through hole.

[0047] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the channel plate layer further includes a support column located in the waste liquid groove;

[0048] The microfluidic chip further includes a liquid absorption core located on the support column.

[0049] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the liquid inlet groove, the mixing and lysis channel, and the nucleic acid extraction channel are arranged side by side in sequence in a first direction. The first air pressure driving port and the second air pressure driving port are respectively arranged on both sides of the nucleic acid extraction channel in a second direction. The waste liquid groove and the second air pressure driving port are located on the same side of the nucleic acid extraction channel. The second direction is arranged intersecting with the first direction.

[0050] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, in the second direction, the lengths of the channel plate layer in the area where the liquid inlet groove is located, in the area where the mixing and lysis channel is located, and in the area where the nucleic acid extraction channel is located increase in sequence.

[0051] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the channel plate layer further includes first positioning holes located on the side of the waste liquid groove away from the nucleic acid extraction channel, and on both sides of the mixing and lysis channel in the second direction; the cover plate layer has second positioning holes at positions corresponding to the first positioning holes.

[0052] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the nucleic acid extraction channel is serpentine.

[0053] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the channel plate layer further includes magnet accommodating grooves on the side facing away from the cover plate layer, and the magnet accommodating grooves are located in the area where the nucleic acid extraction channel is located and in the area where the mixing and lysis groove is located.

[0054] Optionally, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the channel plate layer further includes a first card slot on the side facing away from the cover plate layer. The orthographic projection of the first card slot on the plane where the cover plate layer is located does not overlap with the orthographic projections of the first air pressure driving port and the second air pressure driving port on the plane where the cover plate layer is located;

[0055] The cover plate layer further includes a second card slot on the side facing away from the channel plate layer, wherein the orthographic projection of the second card slot on the plane where the cover plate layer is located overlaps with the orthographic projection of the first card slot on the plane where the cover plate layer is located;

[0056] The microfluidic chip further includes a claw-type connector. A part of the claw-type connector is embedded in the first card slot and the second card slot, and the claw-type connector includes a pressure supply channel communicated with the first air pressure driving port or the second air pressure driving port.

[0057] Optionally, in the above-mentioned microfluidic chip provided in an embodiment of the present disclosure, the channel plate layer further includes a third slot located below the first air pressure driving port and the second air pressure driving port;

[0058] The cover plate layer further includes a fourth slot on a side facing the channel plate layer, wherein the orthographic projection of the fourth slot on the plane where the cover plate layer is located overlaps with the orthographic projection of the third slot on the plane where the cover plate layer is located;

[0059] Parts of the claw-type connector are embedded in the third card slot and the fourth card slot.

[0060] Optionally, in the above-mentioned microfluidic chip provided in an embodiment of the present disclosure, the solution storage cavity includes a liquid storage chamber having a liquid discharge port, an electrode release layer close to one side of the liquid discharge port, and a hot-melt sealing structure, wherein the electrode release layer has an opening at a position corresponding to the liquid discharge port, and the hot-melt sealing structure seals the liquid discharge port and the opening, and the liquid discharge port and the opening constitute the liquid outlet through-hole.

[0061] Optionally, in the above-mentioned microfluidic chip provided by the embodiment of the present disclosure, the hot-melt sealing structure includes a ball valve for sealing the opening, and a thermosensitive structure for fixing the ball valve on the electrode release layer.

[0062] Optionally, in the above-mentioned microfluidic chip provided in an embodiment of the present disclosure, the liquid storage chamber further includes a sealing ring accommodating groove surrounding the liquid discharge port;

[0063] The solution storage cavity further includes a sealing ring and an adhesive. The sealing ring is located in the sealing ring receiving groove, and the adhesive is filled between the sealing ring and the sealing ring receiving groove.

[0064] Optionally, the above-mentioned microfluidic chip provided in the embodiment of the present disclosure further includes a liquid storage chamber cover and a waterproof membrane, the liquid storage chamber cover is provided with an exhaust port, and the waterproof membrane covers the exhaust port.

[0065] Optionally, in the above-mentioned microfluidic chip provided by the embodiment of the present disclosure, the cover layer further includes a fifth card slot surrounding the liquid inlet hole on a side away from the channel layer, and the electrode release layer is embedded in the fifth card slot.

[0066] On the other hand, the present disclosure also provides a method for extracting nucleic acids using the microfluidic chip, comprising:

[0067] A sample liquid and a lysis reagent are mixed and added to the solution storage chamber, and the solution storage chamber is controlled to release the mixed liquid of the sample liquid and the lysis reagent, as well as the reagent pre-stored in the solution storage chamber;

[0068] Alternately applying positive pressure and negative pressure through the second air pressure driving port to introduce the sample liquid, the lysis reagent, and the pre-stored reagent into the mixed lysis channel for mixing and lysing the nucleic acid;

[0069] Positive pressure and negative pressure are alternately applied through the first air pressure driving port to introduce the mixed solution after the nucleic acid is lysed into the nucleic acid extraction channel to separate and extract the nucleic acid.

[0070] On the other hand, an embodiment of the present disclosure further provides a nucleic acid extraction device, comprising a microfluidic chip and a magnetic supply component, wherein the microfluidic chip is the above-mentioned microfluidic chip, and the magnetic supply component is located on the side of the channel plate layer away from the cover plate layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Figure 1 A schematic diagram of the structure of a microfluidic chip provided in an embodiment of the present disclosure;

[0072] Figure 2 A schematic diagram of the structure of each layer in the microfluidic chip provided in an embodiment of the present disclosure;

[0073] Figure 3 A schematic structural diagram of a channel plate layer provided in an embodiment of the present disclosure;

[0074] Figure 4 A schematic structural diagram of a cover layer provided in an embodiment of the present disclosure;

[0075] Figure 5 A schematic structural diagram of a fifth channel between a fifth valve and a waste liquid groove provided in an embodiment of the present disclosure;

[0076] Figure 6 A schematic diagram of another structure of the fifth channel between the fifth valve and the waste liquid groove provided in an embodiment of the present disclosure;

[0077] Figure 7 A schematic diagram of another structure of the fifth channel between the fifth valve and the waste liquid groove provided in an embodiment of the present disclosure;

[0078] Figure 8 A schematic diagram of another structure of the fifth channel between the fifth valve and the waste liquid groove provided in an embodiment of the present disclosure;

[0079] Figure 9 A schematic diagram of a valve in an open state provided by an embodiment of the present disclosure;

[0080] Figure 10 for Figure 9 A schematic diagram of the valve shown in the closed state;

[0081] Figure 11Another schematic diagram of the valve provided by the embodiment of the present disclosure in the open state;

[0082] Figure 12 For Figure 11 A schematic diagram of the shown valve in the closed state;

[0083] Figure 13 Another structural schematic diagram of each layer in the microfluidic chip provided by the embodiment of the present disclosure;

[0084] Figure 14 Another schematic diagram of the valve provided by the embodiment of the present disclosure in the open state;

[0085] Figure 15 For Figure 14 A schematic diagram of the shown valve in the closed state;

[0086] Figure 16 Another schematic diagram of the valve provided by the embodiment of the present disclosure in the open state;

[0087] Figure 17 For Figure 16 A schematic diagram of the shown valve in the closed state;

[0088] Figure 18 A simplified structural schematic diagram of the microfluidic chip provided by the embodiment of the present disclosure;

[0089] Figure 19 Another simplified structural schematic diagram of the microfluidic chip provided by the embodiment of the present disclosure;

[0090] Figure 20 Another simplified structural schematic diagram of the microfluidic chip provided by the embodiment of the present disclosure;

[0091] Figure 21 A structural schematic diagram of the claw-type connector provided by the embodiment of the present disclosure;

[0092] Figure 22 A structural schematic diagram of the solution storage cavity provided by the embodiment of the present disclosure;

[0093] Figure 23 A flowchart of the nucleic acid extraction method provided by the embodiment of the present disclosure. Detailed implementation manners

[0094] To make the objectives, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present disclosure. It should be noted that the sizes and shapes of the figures in the drawings do not reflect the actual proportions, and the purpose is only to illustrate the content of the present disclosure schematically. And the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout.

[0095] Unless otherwise defined, technical terms or scientific terms used herein shall have the ordinary meanings as understood by those of ordinary skill in the art to which this disclosure pertains. The terms "first", "second" and similar terms used in the specification and claims of this disclosure do not denote any order, quantity or importance, but are only used to distinguish different components. Words such as "comprising" or "including" mean that the elements or items appearing before such words cover the elements or items listed after such words and their equivalents, without excluding other elements or items. Terms such as "inside", "outside", "above", "below", etc. are only used to indicate relative positional relationships, and when the absolute position of the object being described changes, such relative positional relationships may also change accordingly.

[0096] To keep the following description of the embodiments of this disclosure clear and concise, detailed descriptions of known functions and known components are omitted in this disclosure.

[0097] A microfluidic chip provided by an embodiment of this disclosure, as Figures 1 to 4 shown, includes:

[0098] A channel plate layer 01, which includes: a liquid inlet groove 101, a mixing and lysis channel 102, a nucleic acid extraction channel 103, a first pneumatic driving port 104 and a second pneumatic driving port 105. Among them, the liquid inlet groove 101, the mixing and lysis channel 102, the nucleic acid extraction channel 103 and the first pneumatic driving port 104 are sequentially connected to form a liquid flow channel, and the liquid inlet groove 101, the mixing and lysis channel 102 and the second pneumatic driving port 105 are sequentially connected to form another liquid flow channel;

[0099] A cover plate layer 02, which is disposed opposite to the channel plate layer 01, and the cover plate layer 02 includes a liquid inlet through hole 201 corresponding to the liquid inlet groove 101;

[0100] A solution storage cavity 03, which is located on the side of the cover plate layer 02 away from the channel plate layer 01, and the solution storage cavity 03 includes a liquid outlet through hole corresponding to the liquid inlet through hole 201.

[0101] In the above microfluidic chip provided by the embodiments of the present disclosure, after the lysis reagent is mixed with the sample solution, the mixture is added to the solution storage chamber 03, and the solution storage chamber 03 is controlled to release the mixture of the sample solution and the lysis reagent, as well as the reagents pre-stored in the solution storage chamber 03; then, under the driving of the positive pressure and negative pressure alternately applied to the second air pressure driving port 105, the sample solution and the reagent are introduced into the mixing and lysis channel 102, and flow back and forth in the mixing and lysis channel 102 to be fully mixed, effectively lysing out nucleic acids; finally, under the driving of the positive pressure and negative pressure alternately applied to the first air pressure driving port 104, the mixture after nucleic acid lysis is introduced into the nucleic acid extraction channel 103, and flows back and forth in the nucleic acid extraction channel 103 to realize the separation and extraction of nucleic acids.

[0102] As can be seen from the above, in the present disclosure, except for the step of adding the sample solution, the entire nucleic acid extraction process is an operation in the microfluidic chip, which not only reduces the risk that the operator may be exposed to the sample solution outside, but also simplifies the operation process, reduces the error that may be caused by manual operation, and at the same time avoids the user from providing the operation container by himself, and the portability is also improved.

[0103] In some embodiments, the materials of the channel plate layer 01 and the cover plate layer 02 can be polymethyl methacrylate (PMMA).

[0104] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, in order to facilitate the addition of different reagents (such as magnetic bead buffer, binding solution, washing solution, elution solution, etc.), as Figures 2 to 4 shown, the solution storage chamber 03 includes a magnetic bead buffer storage chamber 301, a binding solution storage chamber 302, a washing solution storage chamber 303, and an elution solution storage chamber 304;

[0105] The liquid inlet through holes 201 include a magnetic bead buffer liquid inlet through hole a1, a binding solution liquid inlet through hole a2, a washing solution liquid inlet through hole a3, and an elution solution liquid inlet through hole a4;

[0106] The liquid inlet grooves 101 include: a magnetic bead buffer liquid inlet groove b1, a binding solution liquid inlet groove b2, a washing solution liquid inlet groove b3, and an elution solution liquid inlet groove b4;

[0107] Among them, the magnetic bead buffer storage chamber 301, the magnetic bead buffer liquid inlet through hole a1, and the magnetic bead buffer liquid inlet groove b1 are sequentially connected;

[0108] The binding solution storage chamber 302, the binding solution liquid inlet through hole a2, and the binding solution liquid inlet groove b2 are sequentially connected;

[0109] The washing solution storage chamber 303, the washing solution liquid inlet through hole a3, and the washing solution liquid inlet groove b3 are sequentially connected;

[0110] The eluent storage cavity 304, the eluent inlet through-hole a4, and the eluent inlet groove b4 are sequentially communicated.

[0111] In some embodiments, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, in order to facilitate the independent flow of different reagents (such as magnetic bead buffer, binding solution, washing solution, eluent, etc.), as Figure 2 and Figure 3 shown, the mixing and lysis channel 102 may include a mixing and lysis groove 1021, a first channel A directly connecting the mixing and lysis groove 1021 and the magnetic bead buffer inlet groove b1, a second channel B directly connecting the mixing and lysis groove 1021 and the binding solution inlet groove b2, a third channel C directly connecting the mixing and lysis groove 1021 and the washing solution inlet groove b3, a fourth channel D directly connecting the mixing and lysis groove 1021 and the eluent inlet groove b4, a fifth channel E indirectly connecting the mixing and lysis groove 1021 and the second pneumatic driving port 105, and a sixth channel F directly connecting the mixing and lysis groove 1021 and the nucleic acid extraction channel 103.

[0112] In some embodiments, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, as Figure 2 and Figure 3 shown, it may further include: a first valve 41 for controlling whether the liquid in the first channel A flows, a second valve 42 for controlling whether the liquid in the second channel B flows, a third valve 43 for controlling whether the liquid in the third channel C flows, a fourth valve 44 for controlling whether the liquid in the fourth channel D flows, a fifth valve 45 for controlling whether the liquid in the fifth channel E flows, and a sixth valve 46 for controlling whether the liquid in the sixth channel F flows. By setting valves at different channels, the back-and-forth flow of liquid in different channels can be better controlled, the time for lysing nucleic acids and separating and extracting nucleic acids can be increased, and thus nucleic acids with higher purity can be obtained. The first valve, the second valve, the third valve, the fourth valve, the fifth valve, and the sixth valve can be magnetic valves or pneumatic valves.

[0113] In specific implementation, the first step: the magnetic bead buffer can be pre-stored in the magnetic bead buffer storage cavity 301, the binding solution can be pre-stored in the binding solution storage cavity 302, the washing solution can be pre-stored in the washing solution storage cavity 303, and the eluent can be stored in the eluent storage cavity 304.

[0114] Step 2: Mix the lysis reagent with the sample solution. Then add it to the magnetic bead buffer storage chamber 301 and mix it evenly with the magnetic bead buffer in the magnetic bead buffer storage chamber 301. Open the first valve 41 and the fifth valve 45, and close the remaining valves, so that the mixed liquid of the magnetic bead buffer, the lysis reagent and the sample solution in the magnetic bead buffer storage chamber 301 is introduced into the mixing and lysis groove 1021 through the opened first valve 41 from the first channel A, and nucleic acids are lysed. The lysed nucleic acids are adsorbed by the magnetic beads in the mixing and lysis groove 1021. And the magnetic beads can be adsorbed on the inner wall of the mixing and lysis groove 1021 by a magnetic supply component such as an electromagnet. The waste liquid generated by lysis is discharged through the opened fifth valve 45 from the fifth channel E.

[0115] Step 3: Open the second valve 42 and the fifth valve 45, and close the remaining valves. At this time, the binding solution in the binding solution storage chamber 302 is released into the mixing and lysis groove 1021 through the opened second valve 42 from the second channel B. Driven by the positive and negative pressures alternately at the second air pressure driving port 105, the magnetic beads adsorbed with nucleic acids flow back and forth in the mixing and lysis groove 1021 to fully increase the binding force between the magnetic beads and the nucleic acids. Then the magnetic beads are adsorbed on the inner wall of the mixing and lysis groove 1021 by a magnetic supply component such as an electromagnet, and the waste liquid is discharged through the opened fifth valve 45 from the fifth channel E.

[0116] Step 4: Open the third valve 43 and the sixth valve 46, and close the remaining valves. At this time, the washing solution in the washing solution storage chamber 303 is released into the mixing and lysis groove 1021 through the opened third valve 43 from the third channel C. Driven by the positive and negative pressures alternately at the first air pressure driving port 104, the magnetic beads adsorbed with nucleic acids and the washing solution flow back and forth between the mixing and lysis groove 1021 and the nucleic acid extraction channel 103 through the opened sixth valve 46 and via the sixth channel F to effectively wash the magnetic beads adsorbed with nucleic acids. After flowing back and forth many times, the magnetic beads adsorbed with nucleic acids finally enter the nucleic acid extraction channel 103, and then the magnetic beads are adsorbed on the inner wall of the nucleic acid extraction channel 103 in the electromagnet accommodation groove by a magnetic supply component such as an electromagnet. The waste liquid is discharged by the negative pressure driving at the second air pressure driving port 105.

[0117] Step 5: Close all the valves, and alternately drive the positive and negative pressures at the first air pressure driving port 104 and the second air pressure driving port 105 to blow and suck air back and forth inside the nucleic acid extraction channel 103 to volatilize the residual organic reagents on the magnetic beads adsorbed with nucleic acids.

[0118] Step 6: Open the fourth valve 44 and the sixth valve 46, and close the remaining valves. At this time, the eluent in the eluent storage chamber 304 is released into the mixing and lysis groove 1021 through the opened fourth valve 44 by the fourth channel D, and then enters the nucleic acid extraction channel 103 through the opened sixth valve 46 and via the sixth channel F. Under the alternating positive and negative pressure driving of the first air pressure driving port 104, the eluent and the magnetic beads adsorbed with nucleic acids flow back and forth in the mixing and lysis groove 1021 and the nucleic acid extraction channel 103 (i.e., ensure that the magnetic beads are in a suspended state). In the state where the magnetic beads are suspended, incubate at a temperature of 56 °C for 5 minutes, so as to separate the magnetic beads from the nucleic acids and obtain pure nucleic acids.

[0119] Step 7: Close all valves, and adsorb the magnetic beads on the inner wall of the nucleic acid extraction channel 103 in the electromagnet accommodating groove through a magnetic supply component such as an electromagnet. And through the negative pressure driving of the first air pressure driving port 104, the eluent containing nucleic acids is discharged from the nucleic acid extraction channel 103. For example, a product recovery tube can be externally connected to the first air pressure driving port 104 to recover the eluent containing nucleic acids into the product recovery tube, which is convenient for subsequent detection.

[0120] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, the width and depth ranges of the first channel A to the sixth channel F are both 0.3 mm to 1 mm, preferably 1 mm × 0.5 mm (width × depth).

[0121] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figure 2 and Figure 3 shown, the fifth channel E between the fifth valve 45 and the second air pressure driving port is zigzag, Figure 3 and specifically shows an "L"-shaped zigzag. The zigzag fifth channel E includes a first part E11 and a second part E12 that are cross-set and communicate with each other. Among them, the first part E11 is directly communicated with the fifth valve 45, and the second part E12 is indirectly communicated with the second air pressure driving port 105 (specifically, there is a waste liquid groove 106 that is directly communicated with both of them between the second part E12 and the second air pressure driving port 105). The length of the first part E11 can be greater than the length of the second part E12. The above setting method can effectively prevent the waste liquid in the waste liquid groove 106 from flowing back.

[0122] In addition, considering that too small an angle between the first part E11 and the second part E12 will increase the resistance of the liquid entering the waste liquid groove 106, and too large an angle will not play a buffering role for the liquid. Therefore, to improve this technical problem, as Figures 5 to 8As shown, the included angle between the first part E11 and the second part E12 can be 30° to 150°, that is, greater than or equal to 30° and less than or equal to 150°. Optionally, the included angle position between the first part E11 and the second part E12 can be Figure 5 the straight corner shown in Figures 6 to 8 or the arc corner shown in

[0123] which is not limited herein. Figures 2 to 10 In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as

[0124] shown, any one of the first valve 41, the second valve 42, the third valve 43, the fourth valve 44, the fifth valve 45 and the sixth valve 46 includes: a first limiting through hole 401 on the channel plate layer 01, a second limiting through hole 402 correspondingly arranged on the cover plate layer 02 and corresponding to the first limiting through hole 401, a valve core 403 moving between the first limiting through hole 401 and the second limiting through hole 402, a bottom film 404 sealing the first limiting through hole 401 on the side of the channel plate layer 01 facing away from the cover plate layer 02, and an elastic film 405 carrying the valve core 403 on the side of the cover plate layer 02 facing the channel plate layer 01, and the elastic film 405 covers the second limiting through hole 402.

[0124] In specific implementation, on the one hand, as Figure 5 shown, in the case of not being affected by an external magnetic force, part or all of the valve core 403 is located in the second limiting through hole 402, and the elastic film 405 seals the second limiting through hole 402, so that the first limiting through hole 401 is in a communicating state, ensuring the normal flow of liquid, thereby opening the valve. On the other hand, as Figure 10 shown, the valve core 403 can be adsorbed by a magnetic supply component such as an electromagnet, so that at least part (that is, part or all of the valve core 403) of the valve core 403 is located in the first limiting through hole 401 without displacement, and the elastic film 405 seals the first limiting through hole 401 under the pressure of the valve core 403 to block the liquid flow, thereby closing the valve. In addition, by arranging the first limiting through hole 401 on the channel plate layer 01 and arranging the bottom film 404 sealing the first limiting through hole 401, not only is the leakage of the first limiting through hole 401 avoided, but also the manufacturing process requirements for the channel plate layer 01 are reduced.

[0125] In some embodiments, the elastic film 405 can be a flexible film such as polydimethylsiloxane (PDMS) with good elasticity. In addition, in order to make the pressure of the valve core 403 on the elastic film 405 smaller to facilitate the normal reset of the elastic film 405, a smaller and lighter valve core 403 can be selected, such as a steel column. [[ID=It]]

[0126] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figures 2 to 4 、 Figure 11 andFigure 12 As shown in Figure 12 , any one of the first valve 41, the second valve 42, the third valve 43, the fourth valve 44, the fifth valve 45, and the sixth valve 46 includes: a limiting groove 401' on the channel plate layer 01, a second limiting through hole 402 correspondingly arranged on the cover plate layer 02 and corresponding to the limiting groove 401', a valve core 403 that moves between the limiting groove 401' and the second limiting through hole 402, and an elastic membrane 405 that bears the valve core 403 on the side of the cover plate layer 02 facing the channel plate layer 01, and the elastic membrane 405 covers the second limiting through hole 402. It can be seen that Figure 11 and Figure 12 The valve type shown in Figure 12 is different from the valve types shown in Figure 5 and Figure 10 in that the first limiting through hole 401 of the channel plate layer 01 can be replaced by the limiting groove 401', thus saving the bottom film 404, but with higher process requirements. In some embodiments, if the thickness of the bottom film 404 or the thickness of the bottom of the groove is too small, it is not conducive to processing, and if the thickness is too large, it affects the valve response. Based on this, the thickness of the bottom film 404 or the thickness of the bottom of the groove can be within 0.5 mm to 2 mm, preferably 1 mm, to ensure the working distance of the electromagnet, increase the response effect of the valve, and facilitate the process.

[0127] It should be noted that in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, the channel plate layer 01 can not only be Figure 3 a single-layer structure with a relatively simple structure as shown in Figure 3 , but also be Figure 13 a laminated structure with better liquid leakage prevention performance as shown in Figure 13 . Specifically, in Figure 13 Figure 13 , the channel plate layer 01 can include a first channel layer 011, a first glue layer 012, and a second channel layer 013 that are sequentially laminated, wherein the first channel layer 011 is close to the cover plate layer 02;

[0128] The first channel layer 011 includes a first mixing and lysing groove 211, a first sub-channel A1 that directly connects the first valve 41 to the magnetic bead buffer liquid inlet groove b1, a second sub-channel B1 that directly connects the second valve 42 to the binding liquid inlet groove b2, a third sub-channel C1 that directly connects the third valve 43 to the cleaning liquid inlet groove b3, and a fourth sub-channel D1 that directly connects the fourth valve 44 to the elution liquid inlet groove b4;

[0129] The first glue layer 012 includes an independent second mixing and lysing groove 212 and a first nucleic acid extraction channel 1031;

[0130] The second channel layer 013 includes a third mixed lysis groove 213, a second nucleic acid extraction channel 1032, a fifth sub-channel A2 directly connecting the first valve 41 and the third mixed lysis groove 213, a sixth sub-channel B2 directly connecting the second valve 42 and the third mixed lysis groove 213, a seventh sub-channel C2 directly connecting the third valve 43 and the third mixed lysis groove 213, an eighth sub-channel D2 directly connecting the fourth valve 44 and the third mixed lysis groove 213, a ninth sub-channel E1 directly connecting the third mixed lysis groove 213 and the fifth valve 45, a tenth sub-channel E2 indirectly connecting the fifth valve 45 and the second pneumatic driving port 105, an eleventh sub-channel F1 directly connecting the third mixed lysis groove 213 and the sixth valve 46, and a twelfth sub-channel F2 directly connecting the sixth valve 46 and the second nucleic acid extraction channel 1032;

[0131] Among them, the first sub-channel A1 and the fifth sub-channel A2 form the first channel A, the second sub-channel B1 and the sixth sub-channel B2 form the second channel B, the third sub-channel C1 and the seventh sub-channel C2 form the third channel C, the fourth sub-channel D1 and the eighth sub-channel D2 form the fourth channel D, the ninth sub-channel E1 and the tenth sub-channel E2 form the fifth channel E, and the eleventh sub-channel F1 and the twelfth sub-channel F2 form the sixth channel F;

[0132] The first mixed lysis groove 211, the second mixed lysis groove 212, and the third mixed lysis groove 213 are directly connected in sequence to form a mixed lysis groove 1021, and the orthographic projection of the first mixed lysis groove 211 on the plane where the cover layer 02 is located, the orthographic projection of the second mixed lysis groove 212 on the plane where the cover layer 02 is located, and the orthographic projection of the third mixed lysis groove 213 on the plane where the cover layer 02 is located substantially coincide;

[0133] The first nucleic acid extraction channel 1031 and the second nucleic acid extraction channel 1032 are directly connected to form a nucleic acid extraction channel 103, and the orthographic projection of the first nucleic acid extraction channel 1031 on the plane where the cover layer 02 is located substantially coincides with the orthographic projection of the second nucleic acid extraction channel 1032 on the plane where the cover layer 02 is located.

[0134] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, such as Figures 14 to 17As shown, any one of the first valve 41, the second valve 42, the third valve 43, the fourth valve 44, the fifth valve 45 and the sixth valve 46 includes: a first limiting through-hole 401 on the first channel layer 011, a drainage hole 406 directly communicating with the first limiting through-hole 401 on the first adhesive layer 012, a second limiting through-hole 402 correspondingly arranged on the cover plate layer 02 with respect to the first limiting through-hole 401, a valve core 403 moving between the first limiting through-hole 401 and the second limiting through-hole 402, and an elastic membrane 405 bearing the valve core 403 on the side of the cover plate layer 02 facing the channel plate layer 01;

[0135] Among them, as Figure 14 and Figure 15 shown, any one of the first valve 41, the second valve 42, the third valve 43 and the fourth valve 44 is provided with a drainage hole 406; as Figure 16 and Figure 17 shown, any one of the fifth valve 45 and the sixth valve 46 is provided with two drainage holes 406.

[0136] During specific implementation, as Figure 13 shown, after the liquid is injected from the liquid inlet through-hole 201, it flows through the liquid inlet groove 101 and the corresponding sub-channel A1 / B1 / C1 / D1 in sequence, and then reaches the first limiting through-hole 401. As Figure 14 shown, when any one of the first valve 41, the second valve 42, the third valve 43 and the fourth valve 44 is opened, at least part of the valve core 403 is located in the second limiting through-hole 402, the elastic membrane 405 seals the second limiting through-hole 402, and the liquid at the first limiting through-hole 401 is injected into the sub-channel A2 / B2 / C2 / D2 through the drainage hole 406 and then flows out to the third mixing and cracking groove 213. As Figure 15 shown, when any one of the first valve 41, the second valve 42, the third valve 43 and the fourth valve 44 is closed, at least part of the valve core 403 is located in the first limiting through-hole 401, the elastic membrane 405 seals the first limiting through-hole 401, and the liquid at the first limiting through-hole 401 cannot flow. In this case, the first valve 41, the second valve 42, the third valve 43 and the fourth valve 44 are valves of the upper-in and lower-out type.

[0137] In addition, as Figure 13 shown, after the liquid is injected from the liquid inlet through-hole 201, it flows into the third mixing and cracking groove 213 under the control of any one of the first valve 41, the second valve 42, the third valve 43 and the fourth valve 44. As Figure 16 shown, when any one of the fifth valve 45 and the sixth valve 46 is opened, at least part of the valve core 403 is located in the second limiting through-hole 402, the elastic membrane 106 seals the second limiting through-hole 402, and the liquid at the third mixing and cracking groove 213 passes through the sub-channel E1 / F1 and one of the drainage holes 406 (i.e.,Figure 13 and Figure 16 inject it into the first limiting through-hole 401 from the drainage hole 406 on the right side in Figure 13 and Figure 16 flow out from the drainage hole 406 on the left side in Figure 17 As shown in

[0138] It can be seen from the above that when the channel plate layer 01 is a laminated structure, the inlet / outlet of the liquid channel and the valve control space are not on the same layer, so that liquid leakage can be effectively prevented when the valve is closed.

[0139] In some embodiments, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, as Figures 5 to 12 、 Figures 14 to 17 shown, it may further include: a first protective film 407 that seals the second limiting through-hole 402 on the side of the cover plate layer 02 facing away from the channel plate layer 01. This can prevent the valve core 403 from accidentally falling off from the second limiting through-hole 402.

[0140] In some embodiments, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, as Figure 2 、 Figure 4 and Figure 13 shown, the cover plate layer 02 further includes an expansion groove 203 surrounding the second limiting through-hole 402, and the orthographic projection of the expansion groove 203 on the plane where the cover plate layer 02 is located overlaps with the orthographic projection of the elastic membrane 405 on the plane where the cover plate layer 02 is located. The presence of the expansion groove 203 can increase the gas space around the valve, reduce the air pressure change around the valve, and is beneficial to improving the stability of the valve.

[0141] In some embodiments, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, in order to increase the gas space around the valve as much as possible to further improve the stability of the control valve, the expansion groove 203 may include a first expansion groove and / or a second expansion groove, wherein the first expansion groove is located on the side of the cover plate layer 02 facing away from the channel plate layer 01, the second expansion groove is located on the side of the cover plate layer 02 facing the channel plate layer 01, the orthographic projection of the first expansion groove on the plane where the cover plate layer 02 is located is substantially the same as the orthographic projection of the elastic membrane 405 on the plane where the cover plate layer 02 is located, and the orthographic projection of the second expansion groove on the plane where the cover plate layer 02 is located is located within the orthographic projection of the elastic membrane 405 on the plane where the cover plate layer 02 is located.

[0142] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, the distance between the orthographic projection boundary of the second expansion groove on the plane where the cover plate layer 02 is located and the orthographic projection boundary of the elastic membrane 405 on the plane where the cover plate layer 02 is located is 0.5 mm to 1.0 mm, so as to ensure the edge pressing effect of the elastic membrane 405 on the second expansion groove 203.

[0143] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, in order to improve the stability effect of the valve, in the vertical direction of the plane where the cover plate layer 02 is located, the depth of the first expansion groove is 0.8 mm to 1.2 mm, and the depth of the second expansion groove is 11 μm to 50 μm.

[0144] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, the channel plate layer 01 and the cover plate layer 02 can be bonded by thermal pressing or pasted with double-sided tape.

[0145] Specifically, in the case where the channel plate layer 01 and the cover plate layer 02 are bonded by thermal pressing, as Figure 1 and Figure 2 shown, the binding liquid storage cavity 302, the binding liquid inlet through hole a2 and the binding liquid inlet groove b2 are directly communicated in sequence; the cleaning liquid storage cavity 303, the cleaning liquid inlet through hole a3 and the cleaning liquid inlet groove b3 are directly communicated in sequence; the elution liquid storage cavity 304, the elution liquid inlet through hole a4 and the elution liquid inlet groove b4 are directly communicated in sequence.

[0146] In the case where the channel plate layer 01 and the cover plate layer 02 are pasted with double-sided tape, as Figure 13 shown, it may further include a second adhesive layer 05 for bonding the cover plate layer 02 and the channel plate layer 01. The second adhesive layer 05 includes a first through hole c1 directly communicating the binding liquid inlet through hole a1 and the magnetic bead buffer liquid inlet groove b1, a second through hole c2 directly communicating the binding liquid inlet through hole a2 and the binding liquid inlet groove b2, a third through hole c3 directly communicating the cleaning liquid inlet through hole a3 and the cleaning liquid inlet groove b3, a fourth through hole c4 directly communicating the elution liquid inlet through hole a4 and the elution liquid inlet groove b4, a receiving hole d for accommodating the elastic membrane 405, and a fifth through hole e directly communicating the mixing and lysis groove 1021.

[0147] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figure 2 、 Figure 3 and Figure 13 shown, the microfluidic chip further includes magnetic beads (not shown in the figure) located in the mixing and lysis groove 1021.

[0148] In specific implementation, the magnetic beads in the mixing and lysis groove 1021 carry substances matching the nucleic acid and can adsorb the nucleic acid to achieve binding with the nucleic acid. Without the action of an external magnetic force, the magnetic beads adsorbed with nucleic acid can flow back and forth in the mixing and lysis groove 1021 under the drive of positive pressure or negative pressure. When an external magnetic force exists, the magnetic beads adsorbed with nucleic acid will be adsorbed on the inner wall of the mixing and lysis groove 1021. In this case, the waste liquid in the mixing and lysis groove 1021 can be removed by means of negative pressure drive.

[0149] In some embodiments, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, as Figure 2 、 Figure 3 and Figure 13 shown, the mixing and lysis groove 1021 includes a reaction groove 021 and a buffer groove 022 that communicate with each other. Among them, the reaction groove 021 can be directly connected to the first channel A, the second channel B, the third channel C, the fourth channel D, and the sixth channel F respectively, and the buffer groove 022 is directly connected to the fifth channel E, so that the buffer groove 022 is communicated with the second air pressure driving port 105 through the fifth channel E. Such a setting can enable the liquid to flow back and forth in the connected reaction groove 021 and buffer groove 022 for sufficient mixing under the drive of the positive pressure or negative pressure loaded at the second air pressure driving port 105, and the design of the two mixing areas of the reaction groove 021 and the buffer groove 022 can reduce the pollution of the liquid.

[0150] In other embodiments, as Figure 18 shown, the reaction groove 021 can also be directly connected to the first channel A, the second channel B, the third channel C, and the fourth channel D respectively, and the buffer groove 022 is directly connected to the fifth channel E and the sixth channel F respectively, so that the buffer groove 022 is directly connected to the waste liquid groove 106 through the fifth channel E and is communicated with the nucleic acid extraction channel 103 through the sixth channel F. In this way, under the drive of the positive pressure or negative pressure loaded at the first air pressure driving port 104 directly connected to the nucleic acid extraction channel 103 or the second air pressure driving port 105 directly connected to the waste liquid groove 106, the liquid can flow back and forth in the connected reaction groove 021 and buffer groove 022 for sufficient mixing.

[0151] In some embodiments, the fifth channel E between the buffer groove 022 and the fifth valve 45 can be composed of Figure 18 the linear channels shown, or can be composed of Figure 19 and Figure 20 the linear channels and arc channels shown to effectively prevent the backflow of waste liquid.

[0152] In some embodiments, in the above-mentioned microfluidic chip provided by the embodiments of the present disclosure, as Figure 2 、 Figure 4 andFigure 9 As shown, the cover plate layer 02 further includes an enlarged through-hole 202 that completely covers the reaction groove 021. After the cover plate layer 02 is aligned with the channel plate layer 01, the reaction groove 021 and the enlarged through-hole 202 can form a reaction chamber with a larger volume, thereby accommodating more liquid. In some embodiments, the reaction groove 021 and the enlarged through-hole 202 can be circular to facilitate the full mixing of the liquid and thus more effectively lyse nucleic acids.

[0153] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, there may also be a second protective film (not shown in the figure) on the side of the cover plate layer 02 facing away from the channel plate layer 01 to seal the enlarged through-hole 202. This can ensure that there is no air interference when driving the liquid with positive pressure or negative pressure, thereby facilitating the back-and-forth flow of the liquid in the channel.

[0154] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figure 2 、 Figure 3 and Figure 9 shown, the buffer groove 022 can be spindle-shaped with narrow ends and a wide middle. The spindle-shaped streamline is conducive to reducing the dead volume of the liquid. Optionally, the width is the largest at about 1 / 2 to 3 / 4 of the spindle shape.

[0155] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figure 2 、 Figure 3 and Figure 9 shown, the mixing and lysis groove 1021 further includes a diversion channel 023 connecting the reaction groove 021 and the buffer groove 022. The diversion channel 1023 is "S"-shaped to increase the liquid reaction time and more fully lyse nucleic acids.

[0156] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figures 2 to 4 、as well as Figure 9 shown, the channel plate layer 01 further includes a waste liquid groove 106, which is directly connected to the nucleic acid extraction channel 103, the fifth channel E, and the second air pressure driving port 105 respectively; the cover plate layer 02 further includes a waste liquid through-hole 204 corresponding to and communicating with the waste liquid groove 106; the microfluidic chip further includes a waste liquid chamber 06 embedded in the waste liquid through-hole 204. In some embodiments, the waste liquid chamber 06 is in a box shape and can be adhered to the waste liquid through-hole 204 with an adhesive.

[0157] It should be noted that in Figure 9When the middle channel plate layer 01 is a laminated structure, a waste liquid groove 106 can be provided on the side of the first channel layer 011 facing the cover plate layer 02. The waste liquid groove 106 has two inlets, which are directly communicated with the first nucleic acid extraction channel 1031 in the first glue layer 012 and the tenth sub-channel E2 in the second channel layer 013 respectively. And the waste liquid groove 106 has an outlet directly communicated with the second air pressure driving port 105. Cutouts are provided at positions in the first glue layer 012 and the second channel layer 013 opposite to the waste liquid groove 106. In addition, in order to enable the waste liquid collected by the channel plate layer 01 to enter the waste liquid through hole 204 of the cover plate layer 02, the second glue layer 05 bonding the cover plate layer 02 and the channel plate layer 01 needs to be cut off at the waste liquid groove 106, that is, there is an opening f directly above the waste liquid groove 106 in the second glue layer 05. Similarly, in order to enable the reaction groove 021 to communicate with the expansion through hole 202, an opening e needs to be provided in the second glue layer 05 directly above the reaction groove 021.

[0158] In some embodiments, in the above second step, third step and fourth step, the waste liquid discharged by the negative pressure drive through the second air pressure driving port 105 can enter the waste liquid chamber 06, thereby improving the integration of the microfluidic chip. And it can avoid replacing the pressure supply pipe (such as a syringe, etc.) at the second air pressure driving port 105 every time the waste liquid is discharged.

[0159] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figures 2 to 4 and Figure 9 shown, the channel plate layer 01 further includes a support column 107 located in the waste liquid groove 106; the microfluidic chip further includes a liquid absorbing core (not shown in the figure) located on the support column 107. The support column 107 can support the liquid absorbing core so that the liquid absorbing core will not block the channels between the waste liquid groove 106 and the nucleic acid extraction channel 103, the buffer groove 022 and the second air pressure driving port 105 due to excessive extrusion. In some embodiments, the liquid absorbing core can be any liquid-absorbing substance such as liquid absorbing cotton, liquid absorbing paper, water-absorbing silica gel, etc., preferably liquid absorbing cotton that can absorb organic liquids and inorganic liquids. The amount of liquid absorbing cotton is adjusted according to the volume of the waste liquid to be treated. In the present disclosure, the size of the waste liquid chamber 06 is 17.75mm * 7.75mm * 12mm, and the maximum liquid storage volume is 1.5mL, effectively avoiding pollution.

[0160] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figure 2 、 Figure 3 and Figure 9As shown, the liquid inlet groove 101, the mixing and lysis channel 102, and the nucleic acid extraction channel 103 are arranged side by side in sequence in the first direction X. The first air pressure driving port 104 and the second air pressure driving port 105 are respectively arranged on both sides of the nucleic acid extraction channel 103 in the second direction Y. The waste liquid groove 106 and the second air pressure driving port 105 are located on the same side of the nucleic acid extraction channel 103. The second direction Y intersects with the first direction X. With the above arrangement, the first air pressure driving port 104 and the second air pressure driving port 105 can be substantially on the same horizontal plane as each channel, so as to facilitate the rapid ventilation or air extraction into each channel through the first air pressure driving port 104 and the second air pressure driving port 105.

[0161] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figure 1 shown, in the second direction Y, the length of the channel plate layer 01 in the area where the liquid inlet groove 101 is located, the length in the area where the mixing and lysis channel 102 is located, and the length in the area where the nucleic acid extraction channel 103 is located increase in sequence. While integrating the liquid inlet groove 101, the mixing and lysis channel 102, the nucleic acid extraction channel 103, the first air pressure driving port 104, and the second air pressure driving port 105 on the same channel plate layer 01, the volume of the channel plate layer 01 can be ensured to be small, which is convenient for carrying. Correspondingly, the cover plate layer 02 has a shape that substantially coincides with the channel plate layer 01.

[0162] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figures 1 to 4 、and Figure 9 shown, the channel plate layer 01 further includes first positioning holes 108 located on the side of the waste liquid groove 106 away from the nucleic acid extraction channel 103 and on both sides of the mixing and lysis channel 102 in the second direction Y; the cover plate layer 02 has second positioning holes 205 at positions corresponding to the first positioning holes 108. These positioning holes can be used for bonding and alignment of the channel plate layer 01 and the cover plate layer 02.

[0163] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figure 2 、 Figure 3 and Figure 9 shown, the nucleic acid extraction channel 103 is serpentine. In this way, the liquid reaction time can be increased, and the nucleic acid extraction efficiency can be improved.

[0164] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figure 2 、 Figure 3 and Figure 9As shown, the channel plate layer 01 further includes a magnet accommodating groove (not shown in the figure) on the side facing away from the cover plate layer 02. The magnet accommodating groove can be located in the area where the nucleic acid extraction channel 103 is located and the area where the mixing and lysis groove 1021 is located, so that a magnetic component such as an electromagnet can rise to adsorb magnetic beads on the inner wall of the nucleic acid extraction channel 103 or on the inner wall of the mixing and lysis groove 1021, facilitating the separation of nucleic acids.

[0165] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figures 1 to 4 and Figure 21 shown, the channel plate layer 01 further includes a first card slot 109 on the side facing away from the cover plate layer 02. The orthographic projection of the first card slot 109 on the plane where the cover plate layer 02 is located does not overlap with the orthographic projections of the first pneumatic driving port 104 and the second pneumatic driving port 105 on the plane where the cover plate layer 02 is located; the cover plate layer 02 further includes a second card slot 206 on the side facing away from the channel plate layer 01, and the orthographic projection of the second card slot 206 on the plane where the cover plate layer 02 is located overlaps with the orthographic projection of the first card slot 109 on the plane where the cover plate layer 02 is located; the microfluidic chip further includes a claw-type connector 07, and a part of the claw-type connector 07 (specifically, four cuboid protrusions 701) is embedded in the first card slot 109 and the second card slot 206, and the claw-type connector 07 includes a pressure supply channel 702 communicating with the first pneumatic driving port 104 or the second pneumatic driving port 105. By providing the claw-type connector 07 at the first pneumatic driving port 104 and the second pneumatic driving port 105, the airtightness of the entire chip can be increased.

[0166] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figures 1 to 4 and Figure 21 shown, in order to enhance the firmness between the claw-type connector 07 and the channel plate layer 01 and the cover plate layer 02, the channel plate layer 01 further includes a third card slot 110 below the first pneumatic driving port 104 and the second pneumatic driving port 105; the cover plate layer 02 further includes a fourth card slot 207 on the side facing the channel plate layer 01, and the orthographic projection of the fourth card slot 207 on the plane where the cover plate layer 02 is located overlaps with the orthographic projection of the third card slot 110 on the plane where the cover plate layer 02 is located; a part of the claw-type connector 07 (the circular protrusion 703 in the figure) is embedded in the third card slot 110 and the fourth card slot 207.

[0167] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figure 22As shown, the solution storage chamber 03 includes a liquid storage chamber 3011 having a liquid discharge port g, an electrode release layer 3012 on one side close to the liquid discharge port g, and a heat-melting sealing structure (not shown in the figure). Among them, the electrode release layer 3012 has an opening h at a position corresponding to the liquid discharge port g, and the heat-melting sealing structure seals the liquid discharge port g and the opening h, and the liquid discharge port g and the opening h form a liquid outlet through hole.

[0168] In the present disclosure, a certain volume of liquid can be pre-stored in the liquid storage chamber 3011 and sealed with a heat-melting sealing structure for long-term storage. When the liquid needs to be released, only the electrode release layer 3012 needs to be powered on to increase the temperature, so that the heat-melting sealing structure melts, opening the channel between the liquid storage chamber 3011 and the liquid inlet groove 101. The liquid enters the liquid inlet groove 101 due to gravity, and the liquid release is completed, avoiding the risk brought by manually adding reagents, and the structure of the solution storage chamber 03 is simple and convenient for operation and safety.

[0169] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, the heat-melting sealing structure includes a ball valve for sealing the opening h and a thermal structure for fixing the ball valve on the electrode release layer 3012. After the thermal structure is heated and melted, the ball valve will rise to the upper part of the liquid storage chamber 3011 due to the buoyancy effect, so that the liquid in the liquid storage chamber 3011 flows through the liquid discharge port g and the opening h to the mixing and cracking channel 102. In some embodiments, the material of the ball valve can be polyvinyl chloride (PVC), and the material of the thermal structure can be paraffin.

[0170] In some embodiments, in the above microfluidic chip provided by the embodiments of the present disclosure, as Figure 22 shown, the liquid storage chamber 3011 further includes a sealing ring 3013 accommodation groove i surrounding the liquid discharge port g; the solution storage chamber 03 further includes a sealing ring 3013 and an adhesive (not shown in the figure). The sealing ring 3013 is located in the sealing ring accommodation groove i, and the adhesive is filled between the sealing ring 3013 and the sealing ring accommodation groove i to achieve good sealing of the liquid storage chamber 3011 and avoid the volatilization of the liquid pre-stored in the liquid storage chamber 3011.

[0171] In some embodiments, the sealing ring 3013 can be an O-ring with a diameter of 3 mm - 4 mm (preferably 3.5 mm), and the material can be selected from elastic substances such as silica gel, nitrile rubber, and fluororubber, preferably fluororubber. When assembling, the O-ring is slightly convex out of the sealing ring accommodation groove i after being placed in the sealing ring accommodation groove i. After applying glue, the elastic O-ring is completely filled in the sealing ring accommodation groove i by using pressure, which plays a role in isolating the liquid storage chamber 3011 from the adhesive outside the O-ring. At the same time, the O-ring ensures the harm caused by the organic reagent in the liquid storage chamber 3011 to the adhesive.

[0172] In some embodiments, in the above-mentioned microfluidic chip provided in the embodiments of the present disclosure, if Figure 22 As shown, the liquid storage chamber 3011 further includes a liquid storage chamber cover 3014 and a waterproof membrane (not shown). The liquid storage chamber cover 3014 is provided with an exhaust port j, and the waterproof membrane covers the exhaust port j. The waterproof membrane prevents external moisture from entering the liquid storage chamber 3011, prevents the liquid in the liquid storage chamber 3011 from evaporating, and balances the internal and external air pressures of the liquid storage chamber 3011. In some embodiments, the liquid storage chamber 3011 and the liquid storage chamber cover 3014 can be an integrated structure, so that the liquid to be stored can be injected through the exhaust port j, and the waterproof membrane is then placed over the exhaust port j, which is not limited here.

[0173] In some embodiments, in the above-mentioned microfluidic chip provided in the embodiments of the present disclosure, if Figure 1 and Figure 4 As shown, the cover layer 02 further includes a fifth slot 208 surrounding the liquid inlet hole 201 on the side away from the channel layer 01 . The fifth slot 208 is embedded with an electrode release layer 3012 to achieve a fixed connection between the cover layer 02 and the solution storage cavity 03 .

[0174] Based on the same inventive concept, an embodiment of the present disclosure provides a nucleic acid extraction method for the above-mentioned microfluidic chip. Since the principle of solving the problem by the nucleic acid extraction method is similar to the principle of solving the problem by the above-mentioned microfluidic chip, the implementation of the nucleic acid extraction method provided by the embodiment of the present disclosure can refer to the implementation of the above-mentioned microfluidic chip provided by the embodiment of the present disclosure, and the repeated parts will not be repeated.

[0175] Specifically, the present disclosure provides a method for extracting nucleic acid using the microfluidic chip, such as Figure 23 Shown, including:

[0176] S2301, mixing a sample solution and a lysis reagent and adding the mixture to a solution storage chamber, and controlling the solution storage chamber to release the mixed liquid of the sample solution and the lysis reagent, as well as the reagent pre-stored in the solution storage chamber;

[0177] S2302, alternately applying positive and negative pressures through the second air pressure driving port to introduce the sample liquid, lysis reagent, and pre-stored reagent into the mixed lysis channel for mixing and lysing the nucleic acid;

[0178] S2303. Alternately apply positive pressure and negative pressure through the first air pressure driving port to introduce the mixed solution after the nucleic acid is lysed into the nucleic acid extraction channel to separate and extract the nucleic acid.

[0179] In order to better understand the above-mentioned nucleic acid extraction method provided in the embodiments of the present disclosure, it is described in detail below.

[0180] In specific implementation, the nucleic acid extraction method provided in the embodiment of the present disclosure may specifically include the following steps:

[0181] Step 1: 175 μL of magnetic bead buffer can be pre-stored in the magnetic bead buffer storage chamber 301, 300 μL of binding solution in the binding solution storage chamber 302, 600 μL of washing solution in the washing solution storage chamber 303, and 100 μL of elution solution in the elution solution storage.

[0182] Step 2: Using 10 5 cells as the standard sample volume, the cells are diluted with 1× phosphate buffer to serve as the sample solution. The lysis reagent is mixed with the sample solution and incubated at 65 °C for 10 minutes. Then it is added to the magnetic bead buffer storage chamber 301 and mixed evenly with the magnetic bead buffer in the magnetic bead buffer storage chamber 301. Open the first valve 41 and the fifth valve 45, and close the remaining valves, so that the mixed liquid of the magnetic bead buffer, lysis reagent, and sample solution in the magnetic bead buffer storage chamber 301 is introduced into the mixing lysis groove 1021 through the opened fifth valve 45 by the first channel A, and nucleic acids are lysed. The lysed nucleic acids are adsorbed by the magnetic beads in the mixing lysis groove 1021. And the magnetic beads can be adsorbed on the inner wall of the mixing lysis groove 1021 by magnetic supply components such as electromagnets. The waste liquid generated by lysis enters the waste liquid chamber 06 through the opened fifth valve 45 by the fifth channel E and is absorbed by the liquid absorbing core.

[0183] Step 3: Open the second valve 42 and the fifth valve 45, and close the remaining valves. At this time, the binding solution in the binding solution storage chamber 302 is released into the reaction groove 021 through the opened second valve 42 by the second channel B. Driven by the positive and negative pressures alternately at the second air pressure driving port 105, the magnetic beads adsorbed with nucleic acids flow back and forth in the reaction groove 021 and the buffer groove 022 to fully increase the binding force between the magnetic beads and the nucleic acids. Then after standing for 3 minutes, the magnetic beads are adsorbed on the inner wall of the reaction groove 021 by magnetic supply components such as electromagnets, and the waste liquid enters the waste liquid chamber 06 through the opened fifth valve 45 by the fifth channel E and is absorbed by the liquid absorbing core.

[0184] Step 4: Open the third valve 43 and the sixth valve 46, and close the remaining valves. At this time, the washing solution in the washing solution storage chamber 303 is released into the reaction groove 021 through the opened third valve 43 by the third channel C. Driven by the positive and negative pressures alternately at the first air pressure driving port 104, the magnetic beads adsorbed with nucleic acids and the washing solution flow back and forth in the reaction groove 021 and the nucleic acid extraction channel 103 through the opened sixth valve 46 and via the sixth channel F to effectively wash the magnetic beads adsorbed with nucleic acids. After flowing back and forth multiple times, the magnetic beads adsorbed with nucleic acids finally enter the nucleic acid extraction channel 103, and then the magnetic beads are adsorbed on the inner wall of the nucleic acid extraction channel 103 in the electromagnet accommodation groove by magnetic supply components such as electromagnets. The waste liquid enters the waste liquid chamber 06 under the negative pressure drive of the second air pressure driving port 105 and is absorbed by the liquid absorbing core.

[0185] Step 5: Close all valves and alternately drive the first air pressure driving port 104 and the second air pressure driving port 105 with positive and negative pressure to blow air back and forth into the nucleic acid extraction channel 103 to volatilize the organic reagent remaining on the magnetic beads adsorbed with nucleic acid.

[0186] Step 6: Open the fourth valve 44 and the sixth valve 46, and close the remaining valves. At this time, the eluate in the eluate storage chamber 304 is released from the fourth channel D into the reaction groove 021 through the opened fourth valve 44, and then enters the nucleic acid extraction channel 103 through the opened sixth valve 46 and the sixth channel F. Under the alternating positive and negative pressure drive of the first air pressure drive port 104, the eluate and the magnetic beads adsorbed with nucleic acid flow back and forth in the reaction groove 021 and the nucleic acid extraction channel 103 (i.e., to ensure that the magnetic beads are in a suspended state). In the suspended state of the magnetic beads, incubate at 56°C for 5 minutes to separate the magnetic beads from the nucleic acid and obtain pure nucleic acid.

[0187] Step 7: Close all valves, and use a magnetic component such as an electromagnet to adsorb the magnetic beads onto the inner wall of the nucleic acid extraction channel 103 within the electromagnet receiving groove. The eluate containing nucleic acids is then discharged from the nucleic acid extraction channel 103 by negative pressure from the first pneumatic drive port 104. For example, a product recovery tube can be connected to the first pneumatic drive port 104 to recover the eluate containing nucleic acids into the product recovery tube for subsequent testing.

[0188] Based on the same inventive concept, the present disclosure provides a nucleic acid extraction device comprising a microfluidic chip and a magnetic supply component (e.g., an electromagnet), wherein the microfluidic chip is the aforementioned microfluidic chip provided in the present disclosure, and the magnetic supply component is located on the side of the channel plate layer facing away from the cover plate layer. Because the principles for solving the problems of the nucleic acid extraction device are similar to those for solving the problems of the aforementioned microfluidic chip, the implementation of the nucleic acid extraction device provided in the present disclosure can refer to the implementation of the aforementioned microfluidic chip provided in the present disclosure, and any repetitions will not be repeated.

[0189] Although the preferred embodiments of the present disclosure have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present disclosure.

[0190] Obviously, those skilled in the art may make various changes and modifications to the embodiments of the present disclosure without departing from the spirit and scope of the embodiments of the present disclosure. Thus, if such changes and modifications of the embodiments of the present disclosure fall within the scope of the claims of the present disclosure and their equivalents, the present disclosure is intended to include such changes and modifications.

Claims

1. A microfluidic chip, wherein, include: a channel plate layer, the channel plate layer comprising: a liquid inlet groove, a mixing and lysis channel, a nucleic acid extraction channel, a first air pressure drive port, and a second air pressure drive port, wherein the liquid inlet groove, the mixing and lysis channel, the nucleic acid extraction channel, and the first air pressure drive port are sequentially connected to form a liquid flow channel, and the liquid inlet groove, the mixing and lysis channel, and the second air pressure drive port are sequentially connected to form another liquid flow channel; a cover plate layer, arranged opposite to the channel plate layer, the cover plate layer comprising liquid inlet through holes arranged corresponding to the liquid inlet grooves; a solution storage cavity, located on a side of the cover plate layer away from the channel plate layer, the solution storage cavity including a liquid outlet through hole corresponding to the liquid inlet through hole; The mixing and cracking channel includes a mixing and cracking groove, and the mixing and cracking groove includes a buffer groove and a reaction groove interconnected with the buffer groove.

2. The microfluidic chip according to claim 1, wherein The solution storage chamber includes a magnetic bead buffer storage chamber, a binding solution storage chamber, a cleaning solution storage chamber and an eluent storage chamber; The liquid inlet through-holes include a magnetic bead buffer liquid inlet through-hole, a binding liquid liquid inlet through-hole, a cleaning liquid liquid inlet through-hole and an eluent liquid inlet through-hole; The liquid inlet grooves include: a magnetic bead buffer liquid inlet groove, a binding liquid liquid inlet groove, a cleaning liquid liquid inlet groove and an elution liquid liquid inlet groove; Wherein, the magnetic bead buffer storage cavity, the magnetic bead buffer inlet through hole and the magnetic bead buffer inlet groove are connected in sequence; The binding liquid storage cavity, the binding liquid inlet through hole and the binding liquid inlet groove are connected in sequence; The cleaning liquid storage cavity, the cleaning liquid inlet through hole and the cleaning liquid inlet groove are connected in sequence; The eluent storage cavity, the eluent inlet through hole and the eluent inlet groove are connected in sequence.

3. The microfluidic chip according to claim 2, wherein, The mixed lysis channel also includes a first channel directly connecting the mixed lysis groove and the magnetic bead buffer inlet groove, a second channel directly connecting the mixed lysis groove and the binding liquid inlet groove, a third channel directly connecting the mixed lysis groove and the cleaning liquid inlet groove, a fourth channel directly connecting the mixed lysis groove and the elution liquid inlet groove, a fifth channel indirectly connecting the mixed lysis groove and the second air pressure drive port, and a sixth channel directly connecting the mixed lysis groove and the nucleic acid extraction channel.

4. The microfluidic chip according to claim 3, wherein, Also includes: a first valve for controlling whether the liquid in the first channel circulates, a second valve for controlling whether the liquid in the second channel circulates, a third valve for controlling whether the liquid in the third channel circulates, a fourth valve for controlling whether the liquid in the fourth channel circulates, a fifth valve for controlling whether the liquid in the fifth channel circulates, and a sixth valve for controlling whether the liquid in the sixth channel circulates.

5. The microfluidic chip according to claim 4, wherein, The fifth channel between the fifth valve and the second air pressure driving port is in a broken line shape.

6. The microfluidic chip according to claim 5, wherein, The zigzag-line-shaped fifth channel includes a first part and a second part that are cross-arranged and connected to each other, wherein the first part is directly connected to the fifth valve, and the second part is indirectly connected to the second air pressure drive port, and the length of the first part is greater than the length of the second part.

7. The microfluidic chip according to claim 6, wherein, The included angle between the first portion and the second portion is 30° to 150°.

8. The microfluidic chip according to claim 4, wherein, Any one of the first valve, the second valve, the third valve, the fourth valve, the fifth valve and the sixth valve includes: a first limiting through hole on the channel plate layer, a second limiting through hole on the cover plate layer corresponding to the first limiting through hole, a valve core moving between the first limiting through hole and the second limiting through hole, a bottom membrane sealing the first limiting through hole on the side of the channel plate layer facing away from the cover plate layer, and an elastic membrane supporting the valve core on the side of the cover plate layer facing the channel plate layer, and the elastic membrane covering the second limiting through hole.

9. The microfluidic chip according to claim 4, wherein, Any one of the first valve, the second valve, the third valve, the fourth valve, the fifth valve and the sixth valve includes: a limiting groove on the channel plate layer, a second limiting through hole on the cover plate layer corresponding to the limiting groove, a valve core moving between the limiting groove and the second limiting through hole, and an elastic membrane on the side of the cover plate layer facing the channel plate layer that supports the valve core, and the elastic membrane covers the second limiting through hole.

10. The microfluidic chip according to claim 4, wherein, The channel plate layer includes a first channel layer, a first glue layer and a second channel layer stacked in sequence, wherein the first channel layer is close to the cover plate layer; The first channel layer includes a first mixing and lysis groove, a first sub-channel directly connected to the first valve and the magnetic bead buffer inlet groove, a second sub-channel directly connected to the second valve and the binding liquid inlet groove, a third sub-channel directly connected to the third valve and the cleaning liquid inlet groove, and a fourth sub-channel directly connected to the fourth valve and the eluent inlet groove; The first adhesive layer includes a second mixing and lysis groove and a first nucleic acid extraction channel which are independent of each other; The second channel layer includes a third mixing and lysis groove, a second nucleic acid extraction channel, a fifth sub-channel directly connected to the first valve and the third mixing and lysis groove, a sixth sub-channel directly connected to the second valve and the third mixing and lysis groove, a seventh sub-channel directly connected to the third valve and the third mixing and lysis groove, an eighth sub-channel directly connected to the fourth valve and the third mixing and lysis groove, a ninth sub-channel directly connected to the third mixing and lysis groove and the fifth valve, a tenth sub-channel indirectly connected to the fifth valve and the second air pressure driving port, an eleventh sub-channel directly connected to the third mixing and lysis groove and the sixth valve, and a twelfth sub-channel directly connected to the sixth valve and the second nucleic acid extraction channel; Among them, the first sub-channel and the fifth sub-channel constitute the first channel, the second sub-channel and the sixth sub-channel constitute the second channel, the third sub-channel and the seventh sub-channel constitute the third channel, the fourth sub-channel and the eighth sub-channel constitute the fourth channel, the ninth sub-channel and the tenth sub-channel constitute the fifth channel, and the eleventh sub-channel and the twelfth sub-channel constitute the sixth channel; The first mixing and cracking groove, the second mixing and cracking groove, and the third mixing and cracking groove are directly connected in sequence to form the mixing and cracking groove, and the orthographic projection of the first mixing and cracking groove on the plane where the cover plate layer is located, the orthographic projection of the second mixing and cracking groove on the plane where the cover plate layer is located, and the orthographic projection of the third mixing and cracking groove on the plane where the cover plate layer is located coincide; The first nucleic acid extraction channel and the second nucleic acid extraction channel are directly connected to form the nucleic acid extraction channel, and the orthographic projection of the first nucleic acid extraction channel on the plane where the cover plate layer is located coincides with the orthographic projection of the second nucleic acid extraction channel on the plane where the cover plate layer is located.

11. The microfluidic chip according to claim 10, wherein, Any one of the first valve, the second valve, the third valve, the fourth valve, the fifth valve, and the sixth valve includes: a first limiting through hole on the first channel layer, a drainage hole directly communicated with the first limiting through hole on the first glue layer, a second limiting through hole correspondingly arranged on the cover plate layer with respect to the first limiting through hole, a valve core moving between the first limiting through hole and the second limiting through hole, and an elastic membrane carrying the valve core on the side of the cover plate layer facing the first channel layer, and the elastic membrane covers the second limiting through hole; Among them, any one of the first valve, the second valve, the third valve, and the fourth valve is provided with one of the drainage holes, and any one of the fifth valve and the sixth valve is provided with two of the drainage holes.

12. The microfluidic chip according to claim 8, 9 or 11, wherein It further includes: A first protective film for sealing the second limiting through hole on the side of the cover plate layer facing away from the channel plate layer.

13. The microfluidic chip according to claim 8, 9 or 11, wherein The cover plate layer further includes an expansion groove surrounding the second limiting through hole, and the orthographic projection of the expansion groove on the plane where the cover plate layer is located overlaps with the orthographic projection of the elastic membrane on the plane where the cover plate layer is located.

14. The microfluidic chip according to claim 13, wherein, The expansion groove includes a first expansion groove and / or a second expansion groove. Among them, the first expansion groove is located on the side of the cover plate layer facing away from the channel plate layer, the second expansion groove is located on the side of the cover plate layer facing the channel plate layer, the orthographic projection of the first expansion groove on the plane where the cover plate layer is located is the same as the orthographic projection of the elastic membrane on the plane where the cover plate layer is located, and the orthographic projection of the second expansion groove on the plane where the cover plate layer is located is located within the orthographic projection of the elastic membrane on the plane where the cover plate layer is located.

15. The microfluidic chip according to claim 14, wherein, The distance between the boundary of the orthographic projection of the second expansion groove on the plane where the cover plate layer is located and the boundary of the orthographic projection of the elastic membrane on the plane where the cover plate layer is located is 0.5 mm to 1.0 mm.

16. The microfluidic chip according to claim 14, wherein, In a direction perpendicular to the plane where the cover layer is located, the depth of the first capacity expansion groove is 0.8 mm to 1.2 mm, and the depth of the second capacity expansion groove is 11 μm to 50 μm.

17. The microfluidic chip according to claim 8, 9 or 11, wherein, It also includes a second adhesive layer bonding the cover plate layer and the channel plate layer, the second adhesive layer includes a first through hole directly connecting the binding liquid inlet hole and the magnetic bead buffer inlet groove, a second through hole directly connecting the binding liquid inlet hole and the binding liquid inlet groove, a third through hole directly connecting the cleaning liquid inlet hole and the cleaning liquid inlet groove, a fourth through hole directly connecting the elution liquid inlet hole and the elution liquid inlet groove, an accommodating hole for accommodating the elastic membrane, and a fifth through hole directly connecting the mixed lysis groove.

18. The microfluidic chip according to claim 3, wherein, Also included are magnetic beads located in the mixing and lysis grooves.

19. The microfluidic chip according to claim 3, wherein, The reaction groove is directly connected to the first channel, the second channel, the third channel, the fourth channel, and the sixth channel respectively, and the buffer groove is directly connected to the fifth channel.

20. The microfluidic chip according to claim 3, wherein, The reaction groove is directly connected to the first channel, the second channel, the third channel, and the fourth channel respectively, and the buffer groove is directly connected to the fifth channel and the sixth channel respectively.

21. The microfluidic chip according to claim 19 or 20, wherein, The cover plate layer further includes a capacity expansion through hole that completely covers the reaction groove, and a second protective film that seals the capacity expansion through hole on a side of the cover plate layer away from the channel plate layer.

22. The microfluidic chip according to claim 1, wherein, The buffer groove is spindle-shaped, and has the largest width at a position 1 / 2 to 3 / 4 in the spindle-shaped extending direction.

23. The microfluidic chip according to claim 19 or 20, wherein, The mixing and cracking groove further includes a guide channel directly connecting the mixing and cracking groove and the buffer groove, and the guide channel is "S" shaped.

24. The microfluidic chip according to claim 19, wherein, The channel plate layer further includes a waste liquid groove, wherein the waste liquid groove is directly connected to the nucleic acid extraction channel, the fifth channel and the second air pressure driving port respectively; The cover layer further includes a waste liquid through hole correspondingly connected to the waste liquid groove; The microfluidic chip further includes a waste liquid cavity embedded in the waste liquid through hole.

25. The microfluidic chip according to claim 24, wherein, The channel plate layer further includes a support column located in the waste liquid groove; The microfluidic chip further comprises a liquid wick located on the support column.

26. The microfluidic chip according to claim 24, wherein, The liquid inlet groove, the mixed lysis channel and the nucleic acid extraction channel are arranged side by side in sequence in the first direction, the first air pressure driven port and the second air pressure driven port are respectively arranged on both sides of the nucleic acid extraction channel in the second direction, the waste liquid groove and the second air pressure driven port are located on the same side of the nucleic acid extraction channel, and the second direction is arranged to intersect with the first direction.

27. The microfluidic chip according to claim 26, wherein, In the second direction, the length of the channel plate layer in the area where the liquid inlet groove is located, the length in the area where the mixing and lysis channel is located, and the length in the area where the nucleic acid extraction channel is located increases successively.

28. The microfluidic chip according to claim 26, wherein, The channel plate layer also includes a first positioning hole located on the side of the waste liquid groove away from the nucleic acid extraction channel and on both sides of the mixed lysis channel in the second direction; the cover layer has a second positioning hole at a position corresponding to the first positioning hole.

29. The microfluidic chip according to any one of claims 3 to 11 and 18 to 20, wherein, The nucleic acid extraction channel is serpentine.

30. The microfluidic chip according to any one of claims 3 to 11 and 18 to 20, wherein, The channel plate layer further includes a magnet accommodating groove on the side facing away from the cover plate layer, and the magnet accommodating groove is located in the area where the nucleic acid extraction channel is located and the area where the mixing and lysis groove is located.

31. The microfluidic chip according to any one of claims 1 to 11, 18 to 20, wherein, The channel plate layer further includes a first card slot on the side facing away from the cover plate layer, and the orthographic projection of the first card slot on the plane where the cover plate layer is located does not overlap with the orthographic projections of the first air pressure driving port and the second air pressure driving port on the plane where the cover plate layer is located; The cover plate layer further includes a second card slot on the side facing away from the channel plate layer, and the orthographic projection of the second card slot on the plane where the cover plate layer is located overlaps with the orthographic projection of the first card slot on the plane where the cover plate layer is located; 32. The microfluidic chip according to claim 31, wherein, The microfluidic chip further includes a claw-shaped connector, a part of the claw-shaped connector is embedded in the first card slot and the second card slot, and the claw-shaped connector includes a pressure supply channel communicated with the first air pressure driving port or the second air pressure driving port. The channel plate layer further includes a third card slot located below the first air pressure driving port and the second air pressure driving port; The cover plate layer further includes a fourth card slot on the side facing the channel plate layer, and the orthographic projection of the fourth card slot on the plane where the cover plate layer is located overlaps with the orthographic projection of the third card slot on the plane where the cover plate layer is located; 33. The microfluidic chip according to any one of claims 1 to 11 and 18 to 20, wherein A part of the claw-shaped connector is embedded in the third card slot and the fourth card slot.

34. The microfluidic chip according to claim 33, wherein, [[ID=Z]]The solution storage cavity includes a liquid storage chamber having a liquid discharge port, an electrode release layer near the liquid discharge port, and a thermoplastic sealing structure. Wherein, the electrode release layer has an opening at a position corresponding to the liquid discharge port, and the thermoplastic sealing structure seals the liquid discharge port and the opening, and the liquid discharge port and the opening form the liquid outlet through hole.

35. The microfluidic chip according to claim 33, wherein, The thermoplastic sealing structure includes a ball valve for sealing the opening and a thermosensitive structure for fixing the ball valve on the electrode release layer. The liquid storage chamber further includes a sealing ring accommodating groove surrounding the liquid discharge port; 36. The microfluidic chip according to claim 33, wherein, The solution storage cavity further includes a sealing ring and an adhesive. The sealing ring is located in the sealing ring accommodating groove, and the adhesive is filled between the sealing ring and the sealing ring accommodating groove.

37. The microfluidic chip according to claim 33, wherein, It further includes a liquid storage cavity cover and a waterproof film. The liquid storage cavity cover is provided with an exhaust port, and the waterproof film covers the exhaust port.

38. A nucleic acid extraction method for a microfluidic chip according to any one of claims 1 to 37, wherein, The cover plate layer further includes a fifth card slot surrounding the liquid inlet through hole on the side facing away from the channel plate layer, and the electrode release layer is embedded in the fifth card slot. Including: Mix the sample liquid and the lysis reagent and then add them to the solution storage cavity, and control the solution storage cavity to release the mixed liquid of the sample liquid and the lysis reagent and the reagent pre-stored in the solution storage cavity; Alternately apply positive pressure and negative pressure through the second air pressure driving port to introduce the sample liquid, the lysis reagent and the pre-stored reagent into the mixing and lysis channel for mixing, and lyse out nucleic acid; Alternately apply positive pressure and negative pressure through the first air pressure driving port to introduce the mixed liquid after nucleic acid is lysed out into the nucleic acid extraction channel for separating and extracting nucleic acid.

39. A nucleic acid extraction device, wherein, It includes a microfluidic chip and a magnetic supply component, wherein the microfluidic chip is the microfluidic chip according to any one of claims 1 to 37, and the magnetic supply component is located on the side of the channel plate layer away from the cover plate layer.

Images