Nucleic acid extraction microfluidic chip, nucleic acid extraction device and extraction method

Abstract

A nucleic acid extraction microfluidic chip, a nucleic acid extraction device and an extraction method. The nucleic acid extraction microfluidic chip comprises a channel plate (1) comprising: a mixing and cracking zone (100), an extraction zone (200) located on one side of the mixing and cracking zone (100), an air pressure drive port (13) connected to the outside, a first type of channel (14) connecting the mixing and cracking zone (100) and the extraction zone (200), and a second type of channel (15) connecting the extraction zone (200) and the air pressure drive port (13); a cover plate (2) arranged opposite to the channel plate (1), the cover plate (2) having an injection port (160) and a liquid inlet through hole (22) at a position corresponding to the mixing and cracking zone (100); and a solution containing chamber (3) located on a side of the cover plate (2) away from the channel plate (1), the solution containing chamber (3) being connected to the mixing and cracking zone (100) of the channel plate (1) through the liquid inlet through hole (22).

Description

Technical Field

[0001] The present invention relates to the field of microfluidics, and in particular to a nucleic acid extraction microfluidics chip, a nucleic acid extraction device and an extraction method. Background Art

[0002] In the sample preparation process of molecular detection, the separation and purification technology of biomacromolecules and nucleic acids is its most core foundation and also a key technology in life science research and application. The traditional method of nucleic acid extraction mainly adopts the extraction method in the centrifuge tube, which wastes space and reagents and increases the manufacturing cost. With the development and application of microfluidic technology, microfluidic-based nucleic acid extraction methods have been developed. General microfluidic nucleic acid extraction methods only fix silicon dioxide, diatoms and other substances that adsorb nucleic acids on the inner wall of the channel, and then manually pass reagents and remove waste liquids. The method steps are cumbersome, time-consuming and labor-intensive, and the extraction rate and repeatability of the results are poor. In view of this, it is necessary to design and provide an efficient and easy-to-use microfluidic chip integrated nucleic acid extraction chip. Summary of the invention

[0003] The present disclosure provides a nucleic acid extraction microfluidic chip, which includes:

[0004] A channel plate, comprising: a mixing and cracking zone, an extraction zone located on one side of the mixing and cracking zone, an air pressure driving port communicating with the outside, a first type of channel communicating with the mixing and cracking zone and the extraction zone, and a second type of channel communicating with the extraction zone and the air pressure driving port;

[0005] A cover plate is arranged opposite to the channel plate, and the cover plate has a sample inlet and a liquid inlet through hole at a position corresponding to the mixed cracking zone;

[0006] The solution containing chamber is located on a side of the cover plate away from the channel plate, and the solution containing chamber is connected with the mixing and cracking area of ​​the channel plate through the liquid inlet through hole.

[0007] In a possible implementation, the extraction zone includes: an extraction groove having a liquid inlet end and a liquid outlet end;

[0008] The pyrolysis zone comprises: a mixed pyrolysis groove, a first liquid inlet groove, a second liquid inlet groove and a third liquid inlet groove which are arranged in sequence on one side of the mixed pyrolysis groove;

[0009] The first type of channels include: a first channel connecting the first liquid inlet groove and the liquid inlet end, a second channel connecting the second liquid inlet groove and the liquid inlet end, and a third channel connecting the third liquid inlet groove and the liquid inlet end, and the mixing and cracking groove is located in the second channel;

[0010] The second type of channel includes: a fourth channel connecting the liquid outlet and the air pressure drive port;

[0011] The liquid inlet through holes include: a first through hole corresponding to the first liquid inlet groove, a second through hole corresponding to the second liquid inlet groove, and a third through hole corresponding to the third liquid inlet groove;

[0012] In a possible implementation, the solution containing chamber includes:

[0013] A flushing liquid accommodating chamber, connected to the second liquid inlet groove of the channel plate through the first through hole;

[0014] A lysate containing chamber, connected to the second liquid inlet groove of the channel plate through the second through hole;

[0015] The eluent accommodating chamber is communicated with the third liquid inlet groove of the channel plate through the third through hole.

[0016] In a possible embodiment, the air pressure driven port includes a first air pressure driven port and a second air pressure driven port, and the fourth channel includes: a first sub-channel connecting the first air pressure driven port and the liquid outlet, and a second sub-channel connecting the second air pressure driven port and the liquid outlet.

[0017] In a possible implementation manner, the channel plate further includes: a sample storage groove located in the first sub-channel.

[0018] In a possible implementation, the channel plate further includes: a waste liquid storage groove located in the second sub-channel.

[0019] In a possible implementation manner, the first channel, the second channel, and the third channel converge into a liquid inlet channel and communicate with the liquid inlet end;

[0020] The waste liquid storage groove is also connected to the liquid inlet channel through a fifth channel.

[0021] In a possible implementation, the nucleic acid extraction microfluidic chip further includes magnetic beads located in the extraction grooves.

[0022] In a possible implementation, the nucleic acid extraction microfluidic chip further includes: a magnetic bead accommodating cavity located on a side of the cover plate away from the channel plate;

[0023] The pyrolysis zone further comprises: a fourth liquid inlet groove, and a sixth channel connecting the fourth liquid inlet groove and the liquid inlet end;

[0024] The cover plate further comprises: a fourth through hole corresponding to the fourth liquid inlet groove;

[0025] The magnetic bead accommodating chamber is communicated with the fourth liquid inlet groove of the channel plate through the fourth through hole.

[0026] In a possible implementation manner, the first type of channel and the second type of channel are further provided with control valves.

[0027] In a possible implementation, the control valve includes:

[0028] a first control valve, located in the first channel;

[0029] a second control valve, located in the second passage;

[0030] a third control valve, located in the third channel;

[0031] The fourth control valve is located in the second sub-channel and between the waste liquid storage groove and the liquid outlet.

[0032] In a possible embodiment, the control valve is an electromagnetic control valve structure, which includes: an iron block accommodating groove located on the side of the cover plate facing the channel plate, an iron block located in the iron block accommodating groove, and an elastic protective membrane located on the side of the iron block facing the channel plate to seal the iron block accommodating groove.

[0033] In a possible implementation, the control valve is a camshaft pressure rod valve structure, and the camshaft pressure rod valve includes: a rod accommodating groove located on the side of the cover plate facing away from the channel plate, and an elastic protective membrane located on the side of the rod accommodating groove facing the channel plate.

[0034] In a possible embodiment, the control valve is an air pressure driven extrusion valve structure, which includes: an extrusion block accommodating groove located on the side of the cover plate facing away from the channel plate, an extrusion block located in the extrusion accommodating groove, a bottom membrane located on the side of the extrusion block facing away from the channel plate, and an elastic protective membrane located on the side of the extrusion block facing the channel plate; wherein the bottom membrane has an air path access port connected to the extrusion block accommodating groove.

[0035] In a possible implementation, the cover plate is further provided with a protective film accommodating groove for accommodating the elastic protective film on a side facing the channel plate, and the orthographic projection of the protective film accommodating groove on the cover plate covers the orthographic projection of the elastic protective film on the cover plate.

[0036] In a possible implementation, the elastic protective film is made of polydimethylsiloxane.

[0037] In a possible implementation, the main body of the channel plate is rectangular, having a first side and a second side extending along a first direction, and a third side and a fourth side extending along a second direction; the shape of the cover plate is the same as that of the channel plate;

[0038] The channel plate has a first section, a second section and a third section arranged in sequence along the first direction, and the lengths of the first section, the second section and the third section in the second direction decrease in sequence;

[0039] The first air pressure driving port is located at a position where the first subsection of the first side protrudes more than the second subsection, and the second air pressure driving port is located at a position where the first subsection of the second side protrudes more than the second subsection.

[0040] In a possible implementation, the extraction groove is located in the first subdivision; the mixed lysis groove is located in the second subdivision; the lysis liquid accommodating chamber, the flushing liquid accommodating chamber, and the eluent accommodating chamber are located in the area where the third subdivision is located.

[0041] In a possible implementation manner, the extraction groove is in a snake shape.

[0042] The embodiment of the present disclosure also provides a nucleic acid extraction device, which includes the nucleic acid extraction microfluidic chip provided in the embodiment of the present disclosure, and the nucleic acid extraction device also includes a magnetic supply component for providing a magnetic field for the magnetic beads.

[0043] In a possible implementation, when the control valve is an electromagnetic control valve structure, the nucleic acid extraction device further includes an electromagnet, and the electromagnet is located on a side of the channel plate away from the cover plate.

[0044] In a possible implementation, when the control valve is a camshaft pressure rod valve structure, the nucleic acid extraction device further includes a camshaft and a plurality of pressure rods connected to the camshaft.

[0045] The present disclosure also provides a method for extracting nucleic acid using the nucleic acid extraction device provided by the present disclosure, which comprises:

[0046] Injecting a sample solution into the mixed lysis zone through the injection port, and controlling the solution containing cavity to release the lysis solution, so that the sample solution is lysed by the lysis solution to form a mixed solution;

[0047] Negative pressure is applied through the air pressure drive port to move the mixed solution into the extraction area to separate and extract the nucleic acid in the mixed solution.

[0048] In a possible implementation, injecting the sample solution into the mixed lysis zone through the sample inlet and controlling the solution containing chamber to release the lysis solution includes:

[0049] The sample liquid is injected into the mixed lysis groove through the injection port, the lysis liquid containing chamber is controlled to release the lysis liquid, and the lysis liquid is moved into the mixed lysis groove to lyse the sample liquid by the lysis liquid to form a mixed liquid.

[0050] In a possible embodiment, the nucleic acid extraction microfluidic chip includes magnetic beads located in the extraction groove; applying negative pressure through the air pressure drive port to move the mixed solution into the extraction area to separate and extract the nucleic acid in the mixed solution, including:

[0051] Applying negative pressure through the air pressure driving port to move the mixed solution into the extraction groove to mix with the magnetic beads, so that the magnetic beads are combined with the nucleic acid formed by the lysis of the sample solution;

[0052] Control the flushing liquid accommodating chamber to pass the flushing liquid into the extraction groove for a first flushing time, provide a magnetic field through the magnetic supply component to make the magnetic beads adsorbed on the inner wall of the extraction groove, and discharge the liquid flushed from the magnetic beads through the air pressure driving port;

[0053] The magnetic field is closed by the magnetic supply component, and the eluent accommodating chamber is controlled to pass the eluent into the extraction groove, so that the nucleic acid is separated from the magnetic beads.

[0054] In a possible implementation, the channel plate further includes a sample storage groove;

[0055] After controlling the eluent containing chamber to pass the eluent into the extraction groove to separate the nucleic acid from the magnetic beads, the nucleic acid extraction method further includes: moving the nucleic acid into the sample storage groove.

[0056] In a possible implementation, the nucleic acid extraction microfluidic chip further includes a waste liquid storage groove;

[0057] The discharging of the liquid after flushing the magnetic beads through the air pressure driven port comprises: discharging the liquid after flushing the magnetic beads into the storage groove through the air pressure driven port.

[0058] In a possible implementation, the air pressure drive port includes a first air pressure drive port and a second air pressure drive port;

[0059] The step of moving the lysate into the mixed lysate groove comprises: applying negative pressure to the first air pressure driving port to suck the lysate into the mixed lysate groove;

[0060] The step of applying negative pressure through the air pressure driving port to move the mixed solution into the extraction groove to mix with the magnetic beads comprises: applying negative pressure to the first air pressure driving port to move the mixed solution into the extraction groove to mix with the magnetic beads;

[0061] The step of discharging the liquid after washing the magnetic beads through the air pressure driven port comprises: applying negative pressure to the second air pressure driven port to suck the washed liquid into the waste liquid storage groove;

[0062] The step of introducing the nucleic acid into the sample storage cavity includes: applying negative pressure to the first air pressure driving port to suck the nucleic acid into the sample storage groove.

[0063] In a possible implementation, the nucleic acid extraction microfluidic chip further includes: a first control valve, a second control valve, a third control valve and a fourth control valve;

[0064] Before injecting the sample liquid into the mixed lysis groove through the injection port, the nucleic acid extraction method further includes: opening the first control valve, the second control valve, the third control valve and the fourth control valve;

[0065] Before controlling the flushing liquid containing chamber to pass the flushing liquid into the extraction groove, the nucleic acid extraction method further includes: closing the second control valve;

[0066] Before controlling the eluent accommodating chamber to pass the eluent into the mixed lysis groove, the nucleic acid extraction method further includes: closing the first control valve;

[0067] Before moving the nucleic acid into the sample storage groove, the nucleic acid extraction method further includes: closing the fourth control valve.

[0068] In a possible implementation, after the mixed solution is moved into the extraction groove to mix with the magnetic beads, and before the flushing solution containing chamber is controlled to pass the flushing solution into the extraction groove, the nucleic acid extraction method further includes:

[0069] The magnetic field is provided by the magnetic supply component so that the magnetic beads are adsorbed on the inner wall of the serpentine tube, and the liquid that has reacted with the lysate and has not been combined with the magnetic beads is discharged through the second air pressure driven port;

[0070] The magnetic field is closed by the magnet supply component. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0072] Figure 2 A schematic diagram of the structure of a cover plate provided in an embodiment of the present disclosure;

[0073] Figure 3 A schematic diagram of the overall structure of a nucleic acid extraction microfluidic chip provided in an embodiment of the present disclosure;

[0074] Figure 4a A schematic diagram of the structure of a specific channel plate provided in an embodiment of the present disclosure;

[0075] Figure 4b A schematic diagram of the overall structure of a specific nucleic acid extraction microfluidic chip provided in an embodiment of the present disclosure;

[0076] Figure 5a A schematic diagram of an electromagnetic control valve structure provided by an embodiment of the present disclosure when it is turned on;

[0077] Figure 5b A schematic diagram of a solenoid control valve structure provided by an embodiment of the present disclosure when closed;

[0078] Figure 5c A schematic diagram of an electromagnetic control valve structure provided by an embodiment of the present disclosure when it is partially turned on and partially turned off;

[0079] Figure 6 A schematic diagram of the structure of a cover plate provided in an embodiment of the present disclosure at the location of an electromagnetic control valve structure;

[0080] Figure 7a A schematic diagram of a camshaft pressure rod valve provided by an embodiment of the present disclosure when it is turned on;

[0081] Figure 7b A schematic diagram of a camshaft pressure rod valve provided by an embodiment of the present disclosure when it is partially open and partially closed;

[0082] Figure 7c A schematic structural diagram of a camshaft corresponding to a camshaft pressure rod valve structure provided in an embodiment of the present disclosure;

[0083] Figure 8 A schematic diagram of the structure of a cover plate provided in an embodiment of the present disclosure at the location of a camshaft pressure rod valve;

[0084] Figure 9a A schematic diagram of a pneumatically driven extrusion valve structure provided in an embodiment of the present disclosure when it is turned on;

[0085] Figure 9b A schematic diagram of a pneumatically driven extrusion valve structure provided by an embodiment of the present disclosure when it is partially open and partially closed;

[0086] Fig.10 A schematic diagram of the structure of a cover plate provided in an embodiment of the present disclosure at the location of a pneumatic pressure driven extrusion valve structure;

[0087] Fig.11a A schematic diagram of a nucleic acid extraction method provided in an embodiment of the present disclosure;

[0088] Fig.11b A schematic diagram of a specific nucleic acid extraction method provided in an embodiment of the present disclosure;

[0089] Fig.12 A schematic diagram of a specific nucleic acid extraction method provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0090] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0091] Unless otherwise defined, the technical terms or scientific terms used in the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0092] In order to keep the following description of the embodiments of the present disclosure clear and concise, the present disclosure omits detailed descriptions of well-known functions and well-known components.

[0093] See also Figure 1 , Figure 2 and Figure 3 As shown, Figure 1 It is a structural diagram of the opposite side of the channel plate and the cover plate. Figure 2 It is a schematic diagram of the opposite side of the cover plate and the channel plate. Figure 3 The overall structure diagram of a nucleic acid extraction microfluidic chip is shown in FIG. 1 . The present disclosure provides a nucleic acid extraction microfluidic chip, including:

[0094] The channel plate 1 comprises: a mixing and cracking zone 100, an extraction zone 200 located on one side of the mixing and cracking zone 100, a gas pressure driving port 13 communicating with the outside, a first type of channel 14 communicating with the mixing and cracking zone 100 and the extraction zone 200, and a second type of channel 15 communicating with the extraction zone 200 and the gas pressure driving port 13;

[0095] The cover plate 2 is arranged opposite to the channel plate 1, and the cover plate 2 has a sample inlet 160 and a liquid inlet through hole 22 at a position corresponding to the mixing and cracking area 100;

[0096] The solution containing chamber 3 is located on a side of the cover plate 2 away from the channel plate 1 , and the solution containing chamber 3 is connected to the mixing and cracking area 100 of the channel plate 1 through the liquid inlet through hole 22 .

[0097] The nucleic acid extraction microfluidic chip provided by the embodiment of the present disclosure injects a sample liquid into the mixed lysis area 100 through the sample inlet 160 of the cover plate 2, and injects a lysis solution that can lyse the sample liquid into the mixed lysis area 100 through the solution containing chamber 3. In the mixed lysis area 100, the sample liquid is lysed by the lysis solution to lyse the nucleic acid. After that, the mixed liquid after lysis in the mixed lysis area 100 is moved into the extraction area 200, and the nucleic acid formed after lysis in the extraction area 200 can be adsorbed by the magnetic beads 110, and then the flushing liquid is injected through the solution containing chamber 3 for flushing and purification. When the waste liquid after flushing is discharged, a magnetic field is applied by the outside , the magnetic beads 110 are absorbed in the area where the extraction area 200 is located, and then the nucleic acids are also absorbed, and then other liquids are discharged; then an eluent is injected through the solution containing chamber 3, and the eluent can separate the magnetic beads 110 from the nucleic acids, so as to obtain pure nucleic acids. Compared with the devices for obtaining nucleic acids in the prior art, the nucleic acid extraction microfluidic chip provided in the embodiment of the present disclosure can reduce the risk of operators contacting exposed samples, simplify the operation process, and avoid users providing their own operation containers. The entire extraction reaction can be completed in the microfluidic chip, reducing the errors that may be caused by human operations, and the portability is also improved.

[0098] In the specific implementation, see Figure 1 As shown, the extraction zone 200 comprises: an extraction groove 11 having a liquid inlet end A and a liquid outlet end B;

[0099] The cracking zone 100 includes: a mixing cracking groove 16, a first liquid inlet groove 121, a second liquid inlet groove 122 and a third liquid inlet groove 123 arranged in sequence on one side of the mixing cracking groove 16;

[0100] The first type of channel 14 includes: a first channel 141 connecting the first liquid inlet groove 121 and the liquid inlet end A, a second channel 142 connecting the second liquid inlet groove 122 and the liquid inlet end A, a third channel 143 connecting the third liquid inlet groove 123 and the liquid inlet end A, and the mixing and cracking groove 16 is located in the second channel 142;

[0101] The second type of channels 15 include: a fourth channel 15 connecting the liquid outlet B and the air pressure drive port 13;

[0102] The liquid inlet through holes 22 include: a first through hole 221 corresponding to the first liquid inlet groove 121 , a second through hole 222 corresponding to the second liquid inlet groove 122 , and a third through hole 223 corresponding to the third liquid inlet groove 123 .

[0103] The solution containing chamber 3 comprises:

[0104] The flushing liquid accommodating chamber 31 is connected to the second liquid inlet groove 121 of the channel plate 1 through the first through hole 221;

[0105] A lysate containing chamber 32, the lysate containing chamber 32 is connected to the second liquid inlet groove 122 of the channel plate 1 through the second through hole 222;

[0106] The eluent accommodating chamber 33 is communicated with the third liquid inlet groove 123 of the channel plate 1 through the third through hole 223 .

[0107] The magnetic beads 110 are located in the extraction groove 11; specifically, the magnetic beads 110 are magnetic beads that can adsorb the nucleic acid to be extracted, and specifically can carry a substance that matches the nucleic acid to achieve binding with the nucleic acid;

[0108] In a specific implementation, the lysate containing chamber 32, the flushing liquid containing chamber 31, and the eluent containing chamber 33 in the embodiment of the present disclosure may be as follows: Figure 1 The single chamber shown may also be a composite structure including a plurality of sub-chambers. For example, when the lysis solution is specifically composed of a plurality of reagents, mixing the plurality of reagents together may affect the chemical properties of each reagent. In this case, the lysis solution containing chamber 32 may include a plurality of independent sub-lysis solution containing chambers. The plurality of sub-lysis solution containing chambers may be arranged in a row or in a circle. Each sub-lysis solution containing chamber may contain at least one lysis reagent. For example, the lysis solution containing chamber 32 may include a first sub-lysis solution containing chamber, a second sub-lysis solution containing chamber, and a third sub-lysis solution containing chamber. The first sub-lysis solution containing chamber may contain two lysis reagents whose chemical properties do not affect each other (or promote each other), the second sub-lysis solution containing chamber may contain another three lysis reagents whose chemical properties do not affect each other (or promote each other), and the third sub-lysis solution containing chamber may contain another two lysis reagents whose chemical properties do not affect each other (or promote each other).

[0109] In a specific implementation, the lysate chamber 32, the rinse chamber 31, and the eluent chamber 33 may be electrically controlled structures, and an indium tin oxide (ITO) electrode that can be electrically heated may be provided at the bottom, and a bottom wax microvalve that can be heated and melted by electricity, so that the internal reagents are released into the corresponding flow channel. Figure 3 The upper end surfaces of the cylindrical lysate accommodating chamber 32, the flushing liquid accommodating chamber 31, and the eluent accommodating chamber 33 may all be provided with openings ( Figure 3 The liquid receiving chamber 32, the flushing liquid receiving chamber 31, and the eluent receiving chamber 33 can also be flexible bags to release the liquid by squeezing.

[0110] In a specific implementation, the extraction groove 11 may be in a snake shape, so that the volume of the extraction groove 11 can be increased to achieve sufficient mixing of the liquid.

[0111] In specific implementation, combined with Figure 1 or Figure 4a As shown, the air pressure drive port 13 includes a first air pressure drive port 131 and a second air pressure drive port 132, and the fourth channel 15 includes: a first sub-channel 151 connected to the first air pressure drive port 131 and the liquid outlet B, and a second sub-channel 152 connected to the second air pressure drive port 132 and the liquid outlet B. In a specific implementation, the first air pressure drive port 131 can be used as a first negative pressure access port for sucking the lysate in the lysate accommodating chamber 32 into the mixed lysate groove 16, and in subsequent operations, for adsorbing the liquid in the mixed lysate groove 16 into the extraction groove 11; the second air pressure drive port 132 can be used as a second negative pressure access port for sucking out the liquid after flushing in the extraction groove 11. The first air pressure driving port 131 and the second air pressure driving port 132 of the channel plate 1 can be specifically semi-cylindrical grooves, and the cover plate 2 can also be provided with semi-cylindrical grooves 23 at positions corresponding to the first air pressure driving port 131 and the second air pressure driving port 132 of the channel plate 1 (the grooves 23 include a first corresponding air pressure driving port groove 231 corresponding to the first air pressure driving port 131, and a second corresponding air pressure driving port groove 232 corresponding to the second air pressure driving port 132). After the cover plate 2 and the channel plate 1 are matched, a tubular cavity is formed, which is pulled by an external piston to form a structure similar to a syringe, so as to achieve the purpose of applying positive pressure or negative pressure to the inside of the nucleic acid extraction microfluidic chip.

[0112] In specific implementation, combined with Figure 4a and Figure 4bAs shown, the nucleic acid extraction microfluidic chip further includes: a sample storage groove 17 located in the first subchannel 151, and a waste liquid storage groove 18 located in the second subchannel 152. In the disclosed embodiment, the nucleic acid extraction microfluidic chip further includes the sample storage groove 17 and the waste liquid storage groove 18, which can realize the absorption of the purified nucleic acid into the sample storage groove 17, and the absorption of the waste liquid in the extraction groove 11 during the operation into the waste liquid storage groove 18.

[0113] In specific implementation, combined with Figure 4a and Figure 4b As shown, the first channel 141, the second channel 142, and the third channel 143 converge at a liquid inlet channel 144 and are connected to the liquid inlet end A; the waste liquid storage groove 18 is also connected to the liquid inlet channel 144 through the fifth channel 145. In the embodiment of the present disclosure, the waste liquid storage groove 18 is also connected to the liquid inlet channel 144 through the fifth channel 145. In some cases where the magnetic beads 110 are not pre-coated on the extraction groove 11 but the magnetic bead solution is stored in the magnetic bead accommodating chamber (the specific setting method can be similar to the setting method of the lysate storage chamber 32, and can be connected to the mixed lysis groove 16 through the sixth channel, not shown in the figure), the magnetic beads and the lysate mixture can be mixed in the mixed lysis groove 16. For the waste liquid after cell lysis, after the magnetic beads are adsorbed by the magnetic supply component, the waste liquid can be directly discharged into the waste liquid storage groove 18 instead of passing through the extraction groove 11 (serpentine tube), reducing the possibility of subsequent operation contamination caused by the waste liquid entering the extraction groove 11.

[0114] In a specific implementation, the magnetic beads 110 can be pre-coated in the extraction groove 11, that is, the nucleic acid extraction microfluidic chip also includes the magnetic beads 110 located in the extraction groove 11; or, a magnetic bead accommodating chamber for storing the magnetic beads 110 can be separately provided for the magnetic beads, that is, the nucleic acid extraction microfluidic chip also includes: a magnetic bead accommodating chamber located on the side of the cover plate 2 away from the channel plate 1 (not shown in the figure, the specific structure setting method and the connection method with the extraction groove 11 and the mixed lysis groove 16 can be similar to the lysis liquid accommodating chamber 32, the flushing liquid accommodating chamber 31, and the eluent accommodating chamber 33); accordingly, the lysis zone 100 also includes: a fourth liquid inlet groove, and a sixth channel connecting the fourth liquid inlet groove and the liquid inlet end A; the cover plate also includes: a fourth through hole corresponding to the fourth liquid inlet groove; the magnetic bead accommodating chamber is connected to the fourth liquid inlet groove of the channel plate through the fourth through hole; or, the magnetic beads 110 can also be mixed in the lysis liquid accommodating chamber 32 as a lysis liquid in the lysis liquid accommodating chamber 32.

[0115] In specific implementation, combined with Figure 4a and Figure 4bAs shown, the first channel 14 and the second channel 15 are also provided with control valves. Specifically, the control valves include: a first control valve 191, located in the first channel 141; a second control valve 192, located in the second channel 142; a third control valve 193, located in the third channel 143; and a fourth control valve 194, located in the second sub-channel 152 and between the waste liquid storage groove 18 and the liquid outlet B. In the disclosed embodiment, the first control valve 191, the second control valve 192, the third control valve 193, and the fourth control valve 194 are initially in an open state. Before the flushing liquid in the flushing liquid accommodating chamber 31 is sucked into the extraction groove 11 through the first air pressure driving port 131, the second control valve 192 can be controlled to be closed to avoid insufficient negative pressure caused by leakage in the second channel 142 (that is, the channel where the second control valve 192 is located) when negative pressure needs to be introduced into the first channel 141 to drive the liquid; when the flushing liquid in the eluent accommodating chamber 33 is sucked into the extraction groove 11 through the first air pressure driving port 131, the second control valve 192 can be controlled to be closed to avoid insufficient negative pressure caused by leakage in the second channel 142 (that is, the channel where the second control valve 192 is located); Before being sucked into the extraction groove 11, the first control valve 191 can be controlled to be closed to avoid insufficient negative pressure caused by air leakage in the first channel 141 (that is, the channel where the first control valve 191 is located) when negative pressure needs to be introduced into the third channel 143 to drive the liquid; after the flushing liquid accommodating chamber 33 releases the flushing liquid, the third control valve 193 can still remain open so that positive and negative pressure can be applied to the channel later; before the purified nucleic acid is sucked into the sample storage chamber 17, the fourth control valve 194 can be controlled to be closed to avoid sucking the waste liquid in the waste liquid storage chamber 18 into the sample storage chamber 17.

[0116] In a specific implementation, the nucleic acid extraction microfluidic chip further includes: a fifth control valve 195 , located in the liquid inlet channel 144 .

[0117] In the specific implementation, see Figure 5a , Figure 5b , Figure 5c , Figure 6 As shown, the control valve is an electromagnetic control valve structure Z1, that is, at least one of the first control valve 191, the second control valve 192, the third control valve 193, and the fourth control valve 194 is an electromagnetic control valve structure Z1, and the electromagnetic control valve structure Z1 includes: an iron block receiving groove 41 located on the side of the cover plate 2 facing the channel plate 1, an iron block 42 located in the iron block receiving groove 41, and an elastic protective film 43 located on the side of the iron block 42 facing the channel plate 1 to seal the iron block receiving groove 41. In a specific implementation, an electromagnet 44 may also be provided on the side of the channel plate 1 away from the cover plate 2. The electromagnet 44 may specifically be a structure independent of the nucleic acid extraction microfluidic chip. When liquid is required to flow through the position of the electromagnetic control valve structure Z, the electromagnet 44 may be controlled to be powered off, the iron block 42 is completely located in the iron block receiving groove 41, and the liquid may pass through unimpeded, such as Figure 5aWhen the liquid cannot flow through the electromagnetic control valve structure Z1, the electromagnet 44 can be controlled to be energized in the forward direction, and the iron block 42 in the iron block accommodating groove 41 is adsorbed by the electromagnet 44 to block the liquid from flowing through. Figure 5b As shown; the liquid needs to flow through a portion of the electromagnetic control valve structure Z1 (such as Figure 5c The left side of the center needs liquid to flow through), while the solenoid control valve structure Z1 at other positions is blocked (such as Figure 5c When the liquid at the right position in the middle needs to be blocked), the electromagnet 44 at the position where the liquid needs to flow can be controlled to be de-energized or reversely energized to allow the liquid to flow through. When the electromagnetic control valve structure Z1 at the position where the liquid needs to be blocked, the electromagnet 44 is controlled to be energized in the forward direction, and the iron block 42 in the iron block receiving groove 41 is adsorbed by the electromagnet 44 to block the liquid from flowing through. Figure 5c At least one of the first control valve 191, the second control valve 192, the third control valve 193, and the fourth control valve 194 is an electromagnetic control valve structure Z1, which can make the nucleic acid extraction microfluidic chip have the advantages of small device size and good portability.

[0118] In specific implementation, combined with Figure 7a , Figure 7b , Figure 7c , Figure 8 As shown, the control valve is an electromagnetic control valve structure Z2, that is, at least one of the first control valve 191, the second control valve 192, the third control valve 193, and the fourth control valve 194 is a camshaft pressure rod valve structure Z2, and the camshaft pressure rod valve structure Z2 includes: a accommodating rod through groove 51 located on the side of the cover plate 2 away from the channel plate 1, and an elastic protective film 43 located on the side of the accommodating rod through groove 51 facing the channel plate 1. In specific implementation, the camshaft pressure rod valve structure 2 can cooperate with the external camshaft 56, the pressure rod 55, and the connecting rod 57 connecting the pressure rod 55 and the camshaft 56 to be pulled up or down, so as to achieve the blocking or flow of the liquid at the position of the camshaft pressure rod valve structure Z2, such as Figure 7a As shown, when pulled up, the liquid can flow; Figure 7b As shown in the camshaft pressure rod valve structure Z2 on the left side, when it descends, it can block the liquid. The camshaft 56 can be rotated, and different pressure rods 55 can be fixed at different angles with the camshaft to achieve pulling up or lowering of the pressure rods 55 at different positions. A suction cup can be provided at one end of the connecting rod 57 connected to the pressure rod 55 to achieve adsorption of the pressure rod 55. At least one of the first control valve 191, the second control valve 192, the third control valve 193, and the fourth control valve 194 is an electric camshaft pressure rod valve structure Z2, which can make the nucleic acid extraction microfluidic chip have higher reliability.

[0119] In specific implementation, combined with Figure 9a , Figure 9b , Fig.10 As shown, the control valve is an electromagnetic control valve structure Z3, that is, at least one of the first control valve 191, the second control valve 192, the third control valve 193, and the fourth control valve 194 is an air pressure driven extrusion valve structure Z3, and the air pressure driven extrusion valve structure Z3 includes: an extrusion block accommodating groove 61 located on the side of the cover plate 2 away from the channel plate 1, an extrusion block 62 located in the extrusion accommodating groove 61, a bottom film 63 located on the side of the extrusion block 62 away from the channel plate 1, and an elastic protective film 43 located on the side of the extrusion block 62 facing the channel plate 1; wherein the bottom film 63 has an air path access port 630 connected to the extrusion block accommodating groove 61. In a specific implementation, gas can be introduced through the air path access port 630 to enable the extrusion block 62 to squeeze the elastic protective film 43, thereby achieving the circulation or blocking of liquids at different locations of the air pressure driven extrusion valve structures Z3, for example, to Figure 9b The air pressure on the left side of the middle drives the extrusion valve structure Z3 to apply positive pressure, so that the extrusion block 62 squeezes the elastic protective film 43, thereby blocking the flow of liquid. Figure 9b The air pressure-driven squeeze valve structure Z3 on the middle right side applies negative pressure or zero pressure to enable the liquid to circulate.

[0120] In specific implementation, combined with Figure 6 , Figure 8 , Fig.10 As shown, the cover plate 2 is further provided with a protective film receiving groove 45 for receiving the elastic protective film 43 on the side facing the channel plate 1, and the orthographic projection of the protective film receiving groove 45 on the cover plate 2 covers the orthographic projection of the elastic protective film 43 on the cover plate 2. Specifically, the orthographic projection of the protective film receiving groove 45 on the cover plate 2 is a rectangle, and the orthographic projection of the protective film receiving groove 45 on the cover plate 2 coincides with the orthographic projection of the elastic protective film 43 on the cover plate 2.

[0121] In a specific implementation, the material of the elastic protective film 43 is polydimethylsiloxane (PDMS). Specifically, the thickness of the elastic protective film 43 is 90 microns to 110 microns, so that the elastic protective film 43 has good resilience, good use time and response speed.

[0122] In specific implementation, combined with Figure 4aAs shown, the main body shape of the channel plate 1 is rectangular, having a first side K1 and a second side K2 extending along the first direction EF, and a third side K3 and a fourth side K4 extending along the second direction GH; the shape of the cover plate 2 is the same as that of the channel plate 1; wherein the channel plate 2 has a first subsection S1, a second subsection S2 and a third subsection S3 arranged in sequence along the first direction EF, and the lengths of the first subsection S1, the second subsection S2 and the third subsection S3 in the second direction GH decrease in sequence; the first air pressure driving port 131 is located at a position where the first subsection S1 of the first side K1 protrudes more than the second subsection S2, and the second air pressure driving port 132 is located at a position where the first subsection S1 of the second side K2 protrudes more than the second subsection S2, so that the air pressure driving port 13 and each channel are basically located on the same horizontal plane, so as to realize rapid ventilation or exhaust into each channel through the air pressure driving port 13.

[0123] In the specific implementation, the sample storage groove 17, the extraction groove 11, and the waste liquid storage groove 18 are located in the first section S1; the mixed lysis groove 16 is located in the second section S2; the lysis liquid accommodating chamber 32, the flushing liquid accommodating chamber 31, and the eluent accommodating chamber 33 are located in the area where the third section S3 is located.

[0124] In a specific implementation, the width of the internal channels of the nucleic acid extraction microfluidic chip (including the first channel 141, the second channel 142, the third channel 143, the first sub-channel 151, the second sub-channel 152, and the liquid inlet channel 144) in the direction perpendicular to its own extension direction can be 0.4mm-0.6mm, specifically, it can be 0.5mm; the depth in the direction perpendicular to the channel plate 1 is 0.4mm-0.6mm, specifically, it can be 0.5mm; the depth of the protective film accommodating groove 45 on the cover plate 2 in the direction perpendicular to the cover plate 2 is a depression of the order of hundreds of microns, which is used to place a PDMS elastic protective film 43 of equal thickness. Specifically, the thickness of the PDMS elastic film used in the example of the present disclosure is approximately 100um, and accordingly, the depth of the protective film accommodating groove is also 100um.

[0125] In specific implementation, the cover plate 2 and the channel plate 1 can be bonded by ultrasonic welding or double-sided adhesive.

[0126] Since the first control valve 191, the second control valve 192, the third control valve 193, and the fourth control valve 194 are consumable devices, there are certain requirements for the thickness and elasticity of the PDMS film layer in the first control valve 191, the second control valve 192, the third control valve 193, and the fourth control valve 194. The embodiments of the present disclosure have the following exploration schemes and solutions:

[0127] a. Use the curing agent for making PDMS membrane layer and the original solution for making PDMS membrane layer in a ratio of 1:10. After mixing evenly, glue is dripped on a spin coater at a speed of 1000rpm, and heated in an oven at 100 degrees Celsius to form. After the membrane layer is stable, take it out for testing. The thickness of the membrane layer is approximately 150um;

[0128] b. Mix the curing agent and stock solution in a ratio of 1:5. After mixing evenly, apply glue on a spin coater at a speed of 1000 rpm, and heat in an oven at 100 degrees Celsius to form. After the film layer is stable, take it out for testing. The film thickness is approximately 200um.

[0129] c. Use the curing agent and stock solution in a ratio of 1:10. After mixing evenly, apply glue on a spin coater at a speed of 1500rpm, and heat in an oven at 100 degrees Celsius to form. After the film layer is stable, take it out for testing. The film thickness is approximately 100um.

[0130] d. Use a curing agent and stock solution ratio of 1:5, mix well, and then drip glue on a spin coater at a speed of 1500rpm, and heat in a 100 degrees Celsius oven to form. After the film layer is stable, take it out for testing. The film thickness is approximately 170um;

[0131] e. Use the curing agent and stock solution in a ratio of 1:10. After mixing evenly, glue is dripped on a spin coater at a speed of 1800 rpm, and heated in an oven at 100 degrees Celsius to form. After the film layer is stable, take it out for testing. The film thickness is approximately 60um;

[0132] f. Use the curing agent and stock solution in a ratio of 1:5. After mixing evenly, apply glue on a spin coater at a speed of 1800 rpm, and heat in an oven at 100 degrees Celsius to form. After the film layer is stable, take it out for testing. The thickness of the film layer is approximately 90um.

[0133] The PDMS film layers of the above four different conditions a, b, c, d are used to make the elastic protective film in the first control valve 191, the second control valve 192, the third control valve 193, and the fourth control valve 194, respectively. The pull-down property when the first control valve 191, the second control valve 192, the third control valve 193, and the fourth control valve 194 are investigated, and the rebound property when opened and the service life are investigated. The results are as follows:

[0134] a. When the electromagnet is powered on, the film layer is pulled down and closed for about 2.7 seconds; when the electromagnet is powered off, the film layer recovers its deformation for about 0.8 seconds; after 50 cycles of power on and power off, the film layer is not broken and its properties are not changed;

[0135] b. When the electromagnet is powered on, the film layer is pulled down and closed for 3.2 seconds; when the electromagnet is powered off, the film layer recovers its deformation for 0.4 seconds. After 50 cycles of power on and power off, the film layer is not broken and its properties are not changed;

[0136] c. When the electromagnet is powered on, the film is pulled down and closed for 1 second; when the electromagnet is powered off, the film recovers its shape for 1 second; after 50 cycles of power on and power off, the film is not broken and its properties are not changed;

[0137] d. When the electromagnet is powered on, the film layer is pulled down and closed for 1.6 seconds; when the electromagnet is powered off, the film layer recovers its deformation for 0.7 seconds; after 50 cycles of power on and power off, the film layer is not broken and its properties are not changed (permanent deformation);

[0138] e. When the electromagnet is powered on, the film layer is pulled down and closed for 0.4S; when the electromagnet is powered off, the film layer recovers its deformation for 1.2S; after 50 cycles of power on and power off, the film layer is ruptured due to its thickness, but its properties remain unchanged;

[0139] f. When the electromagnet is powered on, the film is pulled down and closed for 1.1 seconds; when the electromagnet is powered off, the film recovers its deformation in 0.9 seconds. After 50 cycles of power on and power off, due to the high hardness / rigidity of the film and the thin thickness of the film, the film is not broken but the deformation is difficult to recover and the properties are changed.

[0140] The PDMS film layer obtained by different components and spin coating conditions basically shows that c is the best implementation scheme, which can take into account the requirements of elastic rigidity and service life and has a fast response speed. It is the elastic layer material manufacturing scheme for the first control valve 191, the second control valve 192, the third control valve 193, and the fourth control valve 194 used in the embodiment of the present disclosure.

[0141] Based on the same disclosed concept, the embodiment of the present disclosure also provides a nucleic acid extraction device, which includes a nucleic acid extraction microfluidic chip as provided in the embodiment of the present disclosure, and the nucleic acid extraction device also includes a magnetic supply component for providing a magnetic field for the magnetic beads, so as to achieve the adsorption of the magnetic beads 110 to the tube wall of the extraction groove 11 or the separation of the magnetic beads 110 from the tube wall of the extraction groove 11 as needed.

[0142] In specific implementation, combined with Figure 5a , Figure 5b and Figure 6 As shown, when the control valve is an electromagnetic control valve structure Z1, the nucleic acid extraction device also includes an electromagnet 44.

[0143] In specific implementation, combined with Figure 7c As shown, when the control valve is a camshaft pressure rod valve structure Z2, the nucleic acid extraction device also includes a camshaft 56 and a plurality of pressure rods 55 connected to the camshaft 56.

[0144] See also Fig.11a As shown, the embodiment of the present disclosure also provides a nucleic acid extraction method of the nucleic acid extraction device provided by the embodiment of the present disclosure, which includes:

[0145] Step S100, injecting a sample solution into the mixed lysis zone through the sample inlet, and controlling the solution containing chamber to release the lysis solution, so as to lyse the sample solution with the lysis solution to form a mixed solution;

[0146] Step S200: negative pressure is applied through the air pressure drive port to move the mixed solution into the extraction area to separate and extract the nucleic acid in the mixed solution.

[0147] In the specific implementation, see Fig.11b As shown, for step S100, injecting sample liquid into the mixed lysis area through the injection port, and controlling the solution containing chamber to release the lysis liquid, it can include: step S110, injecting sample liquid into the mixed lysis groove through the injection port, controlling the lysis liquid containing chamber to release the lysis liquid, and moving the lysis liquid into the mixed lysis groove to lyse the sample liquid through the lysis liquid to form a mixed liquid.

[0148] Regarding step S200, applying negative pressure through the air pressure drive port to move the mixed solution into the extraction area to separate and extract the nucleic acid in the mixed solution, specifically, the following steps may be performed:

[0149] Step S210, applying negative pressure through the air pressure drive port to move the mixed solution into the extraction groove to mix with the magnetic beads, so that the magnetic beads are combined with the nucleic acid formed by the lysis of the sample solution;

[0150] Step S220, control the flushing liquid accommodating chamber to pass the flushing liquid into the extraction groove, flush for a first time, provide a magnetic field through the magnetic supply component to make the magnetic beads adsorbed on the inner wall of the extraction groove, and discharge the liquid after flushing the magnetic beads through the air pressure drive port; specifically, the nucleic acid extraction microfluidic chip also includes a waste liquid storage groove; for discharging the liquid after flushing the magnetic beads through the air pressure drive port in step S220, it includes: discharging the liquid after flushing the magnetic beads into the storage groove through the air pressure drive port;

[0151] Step S230, closing the magnetic field by the magnetic supply component, controlling the eluent holding chamber to pass the eluent into the extraction groove, so as to separate the nucleic acid from the magnetic beads.

[0152] In the specific implementation, see Fig.12 As shown, the channel plate also includes a sample storage groove; after step S230, that is, after controlling the eluent accommodating chamber to pass the eluent into the extraction groove to separate the nucleic acid from the magnetic beads, the sample storage groove is connected to the sample storage groove. Fig.12 As shown, the nucleic acid extraction method further includes: step S300, moving the nucleic acid into the sample storage groove.

[0153] In a specific implementation, the air pressure drive port includes a first air pressure drive port and a second air pressure drive port;

[0154] The step S110 of moving the lysate into the mixed lysate groove includes: applying negative pressure to the first air pressure driving port to suck the lysate into the mixed lysate groove;

[0155] The step S210 of applying negative pressure through the air pressure driving port to move the mixed solution into the extraction groove to mix with the magnetic beads includes: applying negative pressure to the first air pressure driving port to move the mixed solution into the extraction groove to mix with the magnetic beads;

[0156] The step S220 of discharging the liquid after washing the magnetic beads through the air pressure driven port includes: applying negative pressure to the second air pressure driven port to suck the washed liquid into the waste liquid storage groove;

[0157] The step S300 of introducing the nucleic acid into the sample storage cavity includes: applying negative pressure to the first air pressure driving port to suck the nucleic acid into the sample storage groove.

[0158] In a specific implementation, the nucleic acid extraction microfluidic chip further includes: a first control valve, a second control valve, a third control valve and a fourth control valve;

[0159] Before step S100, that is, before injecting the sample liquid into the mixed lysis groove through the injection port, the nucleic acid extraction method further includes: opening the first control valve, the second control valve, the third control valve and the fourth control valve;

[0160] Before controlling the flushing liquid containing chamber to pass the flushing liquid into the extraction groove, the nucleic acid extraction method further includes: closing the second control valve;

[0161] Before controlling the eluent containing chamber to pass the eluent into the mixed lysis groove, the nucleic acid extraction method further includes: closing the first control valve;

[0162] Before moving the nucleic acid into the sample storage groove, the nucleic acid extraction method further includes: closing the fourth control valve.

[0163] In a specific implementation, after step S200 and before step S300, that is, after the mixed solution is moved into the extraction groove to mix with the magnetic beads, and before the flushing solution containing chamber is controlled to pass the flushing solution into the extraction groove, the nucleic acid extraction method further includes:

[0164] The magnetic field is provided by the magnetic supply component so that the magnetic beads are adsorbed on the inner wall of the serpentine tube, and the liquid that has reacted with the lysate and has not been combined with the magnetic beads is discharged through the second air pressure driven port;

[0165] The magnetic field is switched off by means of the magnetic supply component.

[0166] In order to more clearly understand the nucleic acid extraction method provided by the embodiment of the present disclosure, the following Figure 4a and Figure 4bTaking the nucleic acid extraction microfluidic chip shown in FIG. 1 as an example, further detailed description is given as follows:

[0167] Step 1: Control the first control valve 191, the second control valve 192, the third control valve 193 and the fourth control valve 194 to be in an open state, that is, all control valves are initially in an open state by default;

[0168] Step 2: inject the sample liquid into the mixed lysis groove 16 through the injection port 160. After adding the sample, close the injection port 160, control the lysis liquid containing chamber 32 to release the lysis liquid, and apply negative pressure to the first air pressure driving port 131 to suck the lysis liquid into the mixed lysis groove 16, so that the sample liquid is lysed by the lysis liquid to form a mixed liquid. Specifically, cyclic positive and negative pressure can be used to make it fully react for 10 minutes. Specifically, if heating is required, the nucleic acid extraction device can also include: a first heating component set at the position corresponding to the mixed lysis groove 16. Specifically, the first heating component can be set on the side of the channel plate 1 away from the cover plate 2;

[0169] Step 3: applying negative pressure to the first air pressure driving port 131 to move the mixed solution into the extraction groove 11 and mix it with the magnetic beads 110 pre-coated in the extraction groove 11, so that the magnetic beads 110 are combined with the nucleic acid formed by the lysis of the sample solution. Specifically, the positive and negative pressure cycles can be used to make them fully contact and let them stand for 1 minute;

[0170] Step 4: A magnetic field is provided by the magnetic supply component to adsorb the magnetic beads 110 on the inner wall of the extraction groove 11 (serpentine tube), and negative pressure is applied through the second air pressure driving port 132 to suck out the liquid that has reacted with the lysate and has not been combined with the magnetic beads 110 to the waste liquid storage groove 18;

[0171] Step 5: Turn off the magnetic field through the magnetic supply component;

[0172] Step 6: close the second control valve 192;

[0173] Step 7: Control the lysis solution containing chamber 31 to release the flushing liquid, and apply negative pressure to the first air pressure driving port 131 to suck the flushing liquid into the extraction groove 11, flush for a first time, provide a magnetic field through the magnetic supply component, so that the magnetic beads 110 are adsorbed on the inner wall of the extraction groove 11, and discharge the liquid flushed with the magnetic beads 110 to the storage groove 18 through the second air pressure driving port 132; repeat this step at least once;

[0174] Step 8: close the first control valve 191;

[0175] Step nine, closing the magnetic field by the magnetic supply component, controlling the eluent accommodating chamber 33 to release the eluent, and applying negative pressure to the first air pressure driving port 131 to suck the eluent into the extraction groove 11, so that the eluent reacts with the magnetic beads combined with the nucleic acid, so that the nucleic acid and the magnetic beads 11 are separated; specifically, if heating is required, the nucleic acid extraction device may further include: a second heating component arranged at the position corresponding to the extraction groove 11, and the second heating component may be arranged on the side of the channel plate 1 away from the cover plate 2; specifically, the first heating component and the second heating component may be structures independent of the nucleic acid extraction microfluidic chip, and may be arranged on the operating table when performing nucleic acid extraction, and may be arranged at a position corresponding to the nucleic acid extraction microfluidic chip when performing nucleic acid extraction;

[0176] Step 10: close the fourth control valve 194;

[0177] Step 11: Provide a magnetic field through the magnetic supply component to make the magnetic beads 110 adsorb on the inner wall of the extraction groove 11 (serpentine tube), and apply negative pressure to the first air pressure driving port 131 to suck the eluted nucleic acid solution into the sample storage groove 17.

[0178] Specifically, 50uL of lysate can be stored in the lysate storage chamber 31, 600uL of rinsate can be stored in the rinsate storage chamber 32, and 150ul of elution suspension can be stored in the elution storage chamber 33. The extraction magnetic beads 110 can be pre-coated in the extraction groove 11 (serpentine tube), and after the magnetic beads 110 are adsorbed on the tube wall by a magnetic supply component (e.g., a magnet), the supernatant mixed with the magnetic beads 110 is extracted.

[0179] The nucleic acid extraction microfluidic chip provided by the embodiment of the present disclosure injects a sample liquid into the mixed lysis zone through the sample inlet of the cover plate, and injects a lysis solution that can lyse the sample liquid into the mixed lysis zone through the solution containing chamber. In the mixed lysis zone, the sample liquid is lysed by the lysis solution to lyse the nucleic acid. After that, the mixed liquid after lysis in the mixed lysis zone is moved into the extraction zone, and the nucleic acid formed after lysis can be adsorbed by magnetic beads in the extraction zone. Then, a flushing liquid is injected through the solution containing chamber for flushing and purification. When the waste liquid after flushing is discharged, the magnetic beads are adsorbed in the area where the extraction zone is located by applying a magnetic field from the outside, and the nucleic acid is also adsorbed, and other liquids are discharged. Then, an eluent is injected through the solution containing chamber, and the eluent can separate the magnetic beads from the nucleic acid to obtain pure nucleic acid. Compared with the device for obtaining nucleic acid in the prior art, the nucleic acid extraction microfluidic chip provided by the embodiment of the present disclosure can reduce the risk of operators contacting exposed samples, simplify the operation process, and avoid users providing operation containers by themselves. The entire extraction reaction can be completed in the microfluidic chip, reducing the errors that may be caused by human operation, and the portability is also improved.

[0180] 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 concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present disclosure.

[0181] Obviously, those skilled in the art can 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 these modifications and variations 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 also intended to include these modifications and variations.

Claims

1. A nucleic acid extraction microfluidic chip, wherein: include: A channel plate, comprising: a mixing and cracking zone, an extraction zone located on one side of the mixing and cracking zone, an air pressure driving port communicating with the outside, a first type of channel communicating with the mixing and cracking zone and the extraction zone, and a second type of channel communicating with the extraction zone and the air pressure driving port; A cover plate is arranged opposite to the channel plate, and the cover plate has a sample inlet and a liquid inlet through hole at a position corresponding to the mixed cracking zone; A solution containing chamber is located on a side of the cover plate away from the channel plate, and the solution containing chamber is connected with the mixing and cracking area of ​​the channel plate through the liquid inlet through hole; Wherein, the extraction zone comprises: an extraction groove having a liquid inlet end and a liquid outlet end; The pyrolysis zone comprises: a mixed pyrolysis groove, a first liquid inlet groove, a second liquid inlet groove and a third liquid inlet groove which are arranged in sequence on one side of the mixed pyrolysis groove; The first type of channels include: a first channel connecting the first liquid inlet groove and the liquid inlet end, a second channel connecting the second liquid inlet groove and the liquid inlet end, and a third channel connecting the third liquid inlet groove and the liquid inlet end, and the mixing and cracking groove is located in the second channel; The second type of channel includes: a fourth channel connecting the liquid outlet and the air pressure drive port; The liquid inlet through holes include: a first through hole corresponding to the first liquid inlet groove, a second through hole corresponding to the second liquid inlet groove, and a third through hole corresponding to the third liquid inlet groove; The air pressure driving port includes a first air pressure driving port and a second air pressure driving port, and the fourth channel includes: a first sub-channel connecting the first air pressure driving port and the liquid outlet, and a second sub-channel connecting the second air pressure driving port and the liquid outlet; The first air pressure driving port and the second air pressure driving port are semi-cylindrical grooves, and the cover plate is provided with semi-cylindrical grooves at positions corresponding to the first air pressure driving port and the second air pressure driving port. After the cover plate and the channel plate are matched, a tubular cavity is formed, which is pulled by an external piston to form a structure similar to a syringe; The main body of the channel plate is rectangular, having a first side and a second side extending along a first direction, and a third side and a fourth side extending along a second direction; the shape of the cover plate is the same as that of the channel plate; The channel plate has a first section, a second section and a third section arranged in sequence along the first direction, and the lengths of the first section, the second section and the third section in the second direction decrease in sequence; The first air pressure driving port is located at a position where the first subsection of the first side protrudes more than the second subsection, and the second air pressure driving port is located at a position where the first subsection of the second side protrudes more than the second subsection.

2. The nucleic acid extraction microfluidic chip according to claim 1, wherein: The solution containing chamber comprises: a flushing liquid accommodating chamber, connected to the first liquid inlet groove of the channel plate through the first through hole; A lysate containing chamber, connected to the second liquid inlet groove of the channel plate through the second through hole; The eluent accommodating chamber is communicated with the third liquid inlet groove of the channel plate through the third through hole.

3. The nucleic acid extraction microfluidic chip according to claim 1, wherein: The channel plate further includes: a sample storage groove located in the first sub-channel.

4. The nucleic acid extraction microfluidic chip according to claim 3, wherein: The channel plate further includes a waste liquid storage groove located in the second sub-channel.

5. The nucleic acid extraction microfluidic chip according to claim 4, wherein: The first channel, the second channel, and the third channel converge into a liquid inlet channel and communicate with the liquid inlet end; The waste liquid storage groove is also connected to the liquid inlet channel through a fifth channel.

6. The nucleic acid extraction microfluidic chip according to claim 1, wherein: The nucleic acid extraction microfluidic chip also includes magnetic beads located in the extraction grooves.

7. The nucleic acid extraction microfluidic chip according to claim 1, wherein: The nucleic acid extraction microfluidic chip further comprises: a magnetic bead accommodating cavity located on a side of the cover plate away from the channel plate; The pyrolysis zone further comprises: a fourth liquid inlet groove, and a sixth channel connecting the fourth liquid inlet groove and the liquid inlet end; The cover plate further comprises: a fourth through hole corresponding to the fourth liquid inlet groove; The magnetic bead accommodating chamber is communicated with the fourth liquid inlet groove of the channel plate through the fourth through hole.

8. The nucleic acid extraction microfluidic chip according to claim 4, wherein: The first type of channel and the second type of channel are also provided with control valves.

9. The nucleic acid extraction microfluidic chip according to claim 8, wherein: The control valve comprises: a first control valve, located in the first channel; a second control valve, located in the second passage; a third control valve, located in the third channel; The fourth control valve is located in the second sub-channel and between the waste liquid storage groove and the liquid outlet.

10. The nucleic acid extraction microfluidic chip according to claim 8, wherein: The control valve is an electromagnetic control valve structure, which includes: an iron block accommodating groove located on the side of the cover plate facing the channel plate, an iron block located in the iron block accommodating groove, and an elastic protective membrane located on the side of the iron block facing the channel plate to seal the iron block accommodating groove.

11. The nucleic acid extraction microfluidic chip according to claim 8, wherein: The control valve is a camshaft pressure rod valve structure, and the camshaft pressure rod valve comprises: a rod accommodating groove located on the side of the cover plate away from the channel plate, and an elastic protective membrane located on the side of the rod accommodating groove facing the channel plate.

12. The nucleic acid extraction microfluidic chip according to claim 8, wherein: The control valve is an air pressure driven extrusion valve structure, which includes: an extrusion block accommodating groove located on the side of the cover plate away from the channel plate, an extrusion block located in the extrusion block accommodating groove, a bottom membrane located on the side of the extrusion block away from the channel plate, and an elastic protective membrane located on the side of the extrusion block facing the channel plate; wherein the bottom membrane has an air path access port connected to the extrusion block accommodating groove.

13. The nucleic acid extraction microfluidic chip according to any one of claims 10 to 12, wherein: The cover plate is further provided with a protective film accommodating groove for accommodating the elastic protective film on a side facing the channel plate, and the orthographic projection of the protective film accommodating groove on the cover plate covers the orthographic projection of the elastic protective film on the cover plate.

14. The nucleic acid extraction microfluidic chip according to any one of claims 10 to 12, wherein: The material of the elastic protective film is polydimethylsiloxane.

15. The nucleic acid extraction microfluidic chip according to claim 2, wherein: The extraction groove is located in the first subdivision; the mixed lysis groove is located in the second subdivision; the lysis liquid accommodating chamber, the flushing liquid accommodating chamber, and the eluent accommodating chamber are located in the area where the third subdivision is located.

16. The nucleic acid extraction microfluidic chip according to claim 1, wherein: The extraction groove is in a snake shape.

17. A nucleic acid extraction device, wherein: It comprises the nucleic acid extraction microfluidic chip as described in any one of claims 1 to 16, and the nucleic acid extraction device also comprises a magnetic supply component for providing a magnetic field for the magnetic beads in the extraction groove.

18. The nucleic acid extraction device according to claim 17, wherein: When the control valves located in the first type of channels and the second type of channels are electromagnetic control valve structures, the nucleic acid extraction device further includes an electromagnet, and the electromagnet is located on a side of the channel plate away from the cover plate.

19. The nucleic acid extraction device according to claim 17, wherein: When the control valves located in the first type of channels and the second type of channels are camshaft pressure rod valve structures, the nucleic acid extraction device further includes a camshaft and a plurality of pressure rods connected to the camshaft.

20. A method for extracting nucleic acid using the nucleic acid extraction device according to any one of claims 17 to 19, wherein: include: Injecting a sample solution into the mixed lysis zone through the injection port, and controlling the solution containing cavity to release the lysis solution, so that the sample solution is lysed by the lysis solution to form a mixed solution; Negative pressure is applied through the air pressure drive port to move the mixed solution into the extraction area to separate and extract the nucleic acid in the mixed solution.

21. The method for extracting nucleic acid according to claim 20, wherein: The method of injecting the sample solution into the mixed pyrolysis zone through the sample inlet and controlling the solution containing cavity to release the pyrolysis solution comprises: The sample liquid is injected into the mixed lysis groove through the injection port, the lysis liquid containing chamber is controlled to release the lysis liquid, and the lysis liquid is moved into the mixed lysis groove to lyse the sample liquid by the lysis liquid to form a mixed liquid.

22. The method for extracting nucleic acid according to claim 21, wherein: Applying negative pressure through the air pressure drive port to move the mixed solution into the extraction area, and separating and extracting the nucleic acid in the mixed solution, comprising: Applying negative pressure through the air pressure driving port to move the mixed solution into the extraction groove to mix with the magnetic beads, so that the magnetic beads are combined with the nucleic acid formed by the lysis of the sample solution; Control the flushing liquid accommodating chamber to pass the flushing liquid into the extraction groove for a first flushing time, provide a magnetic field through the magnetic supply component to make the magnetic beads adsorbed on the inner wall of the extraction groove, and discharge the liquid flushed from the magnetic beads through the air pressure driving port; The magnetic field is closed by the magnetic supply component, and the eluent accommodating chamber is controlled to pass the eluent into the extraction groove, so that the nucleic acid is separated from the magnetic beads.

23. The method for extracting nucleic acid according to claim 22, wherein: After controlling the eluent containing chamber to pass the eluent into the extraction groove to separate the nucleic acid from the magnetic beads, the nucleic acid extraction method further includes: moving the nucleic acid into a sample storage groove.

24. The method for extracting nucleic acid according to claim 23, wherein: Discharging the liquid after washing the magnetic beads through the air pressure driven port includes: discharging the liquid after washing the magnetic beads into the waste liquid storage groove through the air pressure driven port.

25. The method for extracting nucleic acid according to claim 24, wherein: The step of moving the lysate into the mixed lysate groove comprises: applying negative pressure to a first air pressure driving port to suck the lysate into the mixed lysate groove; The step of applying negative pressure through the air pressure driving port to move the mixed solution into the extraction groove to mix with the magnetic beads comprises: applying negative pressure to the first air pressure driving port to move the mixed solution into the extraction groove to mix with the magnetic beads; The step of discharging the liquid after washing the magnetic beads through the air pressure driven port comprises: applying negative pressure to the second air pressure driven port to suck the washed liquid into the waste liquid storage groove; The step of introducing the nucleic acid into the sample storage groove includes: applying negative pressure to the first air pressure driving port to suck the nucleic acid into the sample storage groove.

26. The method for extracting nucleic acid according to claim 25, wherein: The nucleic acid extraction microfluidic chip also includes: a first control valve, a second control valve, a third control valve and a fourth control valve; Before injecting the sample liquid into the mixed lysis groove through the injection port, the nucleic acid extraction method further includes: opening the first control valve, the second control valve, the third control valve and the fourth control valve; Before controlling the flushing liquid containing chamber to pass the flushing liquid into the extraction groove, the nucleic acid extraction method further includes: closing the second control valve; Before controlling the eluent accommodating chamber to pass the eluent into the mixed lysis groove, the nucleic acid extraction method further includes: closing the first control valve; Before moving the nucleic acid into the sample storage groove, the nucleic acid extraction method further includes: closing the fourth control valve.

27. The method for extracting nucleic acid according to claim 26, wherein: The extraction groove is in a snake shape; after the mixed solution is moved into the extraction groove to mix with the magnetic beads, and before the flushing solution containing chamber is controlled to pass the flushing solution into the extraction groove, the nucleic acid extraction method further includes: The magnetic field is provided by the magnetic supply component so that the magnetic beads are adsorbed on the inner wall of the snake-shaped extraction groove, and the liquid that has reacted with the lysate and has not been combined with the magnetic beads is discharged through the second air pressure driven port; The magnetic field is closed by the magnet supply component.

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