CN113416626A

CN113416626A - Microfluidic device and driving method thereof

Info

Publication number: CN113416626A
Application number: CN202110697436.0A
Authority: CN
Inventors: 白云飞; 席克瑞; 贾振宇; 林柏全; 秦锋; 雷登明; 朱清三
Original assignee: Shanghai Tianma Microelectronics Co Ltd
Current assignee: Shanghai Tianma Microelectronics Co Ltd
Priority date: 2021-06-23
Filing date: 2021-06-23
Publication date: 2021-09-21

Abstract

The invention discloses a micro-fluidic device and a driving method thereof, belonging to the technical field of micro-fluidic, wherein the micro-fluidic device comprises a first substrate, a second substrate and a third substrate which are arranged in a stacking way; the liquid inlet, the first feed inlet and the second feed inlet are formed in the first substrate, the first flow channel and the first collecting pool are formed in one side, facing the first substrate, of the second substrate, the second flow channel and the second collecting pool are formed in one side, facing the second substrate, of the third substrate, and the aperture of the first through holes in the first flow channel is larger than that of the second through holes in the second flow channel. The microfluidic device can further comprise at least a first substrate and a second substrate, wherein a first thin film is arranged on one side, away from the first substrate, of the second substrate, the first thin film comprises any one of a photoinduced deformation thin film or an electrostrictive thin film, and the first thin film comprises a plurality of first sub-holes. The invention can realize the separation and extraction of cell particles through a simple structure, and simultaneously can improve the efficiency, reduce the cost and reduce the pollution risk.

Description

Microfluidic device and driving method thereof

Technical Field

The invention relates to the technical field of microfluidics, in particular to a microfluidic device and a driving method thereof.

Background

The existing microbeads have various extraction types, for example, through chemical reaction, the needed microbeads are subjected to multiple steps of centrifugation, sedimentation and the like according to different situations, or the needed cells are extracted through microscope observation, the efficiency is low, a large amount of chemical reagents are needed, the steps are complicated, the extraction cost is increased, and the pollution risk is caused.

The Micro-fluidic (Micro Fluidics) technology belongs to a new technology, is a new interdiscipline related to chemistry, fluid physics, microelectronics, new materials, biology and biomedical engineering, can accurately control the movement of liquid drops, realizes the operations of fusion, separation and the like of the liquid drops, completes various biochemical reactions, and is a technology which is mainly characterized by controlling the fluid in a micron-scale space. The technology is crossed with chemical, biological, engineering, physics and other subjects, and shows wide application prospect. The micro-fluidic device is a main platform for realizing the micro-fluidic technology, and basic operation units of sample preparation, reaction, separation, detection and the like in the processes of biological, chemical and medical analysis can be integrated on the micro-fluidic device with micron scale, so that the whole analysis process can be automatically completed on the micro-fluidic device. At present, the separation and acquisition of cells with different sizes are required to be carried out firstly whether the detection or the analysis process is finished.

Therefore, it is an urgent technical problem to provide a microfluidic device and a driving method thereof, which can better apply the microfluidic technology to the microfluidic technology of bead extraction, realize the separation and extraction of cells with different sizes, improve efficiency, reduce cost, and reduce the risk of contamination.

Disclosure of Invention

In view of this, the present invention provides a microfluidic device and a driving method thereof, so as to solve the problems of low efficiency, large amount of chemical reagents, complicated steps, increased extraction cost and pollution risk in the extraction of desired cells in the bead extraction structure in the prior art.

The invention discloses a microfluidic device, which at least comprises a first substrate, a second substrate and a third substrate which are arranged in a stacked manner; the first substrate is at least provided with a liquid inlet, a first feed inlet and a second feed inlet, and the liquid inlet, the first feed inlet and the second feed inlet penetrate through the first substrate along the thickness direction of the first substrate; a first flow channel and a first collecting pool are arranged on one side, facing the first substrate, of the second substrate, and the depth of the first flow channel is smaller than the thickness of the second substrate; the liquid inlet is communicated with the first flow channel, the first feed inlet is communicated with a first inlet end of the first flow channel, and the first collecting tank is communicated with a first outlet end of the first flow channel; the first inlet end and the first outlet end are two opposite ends of the first flow channel in the flow direction; a second flow channel and a second collecting pool are formed in one side, facing the second substrate, of the third substrate, and the depth of the second flow channel is smaller than the thickness of the third substrate; the first flow channel is communicated with the second flow channel, the second feed inlet is communicated with the second inlet end of the second flow channel, and the second collecting pool is communicated with the second outlet end of the second flow channel; the second inlet end and the second outlet end are two opposite ends of the second flow channel in the flow direction; the first flow channel comprises a plurality of first through holes, the second flow channel comprises a plurality of second through holes, and the aperture of each first through hole is larger than that of each second through hole in the direction perpendicular to the plane of the first substrate; the liquid inlet is used for flowing in a solution to be treated, the first feeding hole is used for flowing in a first boosting agent to push the solution in the first flow channel to flow into the first collecting pool, and the second feeding hole is used for flowing in a second boosting agent to push the solution in the second flow channel to flow into the second collecting pool.

Based on the same inventive concept, the invention also discloses a driving method of the microfluidic device, the driving method is used for driving the microfluidic device to work, and the driving method comprises the following steps: in the screening stage, the solution to be treated flows into a first flow channel of the second substrate from the liquid inlet, enters a second flow channel of the third substrate after being screened by a first through hole of the first flow channel, and is screened again by a second through hole of the second flow channel; at the moment, a plurality of first particles are left in the first flow channel, and the particle size of the first particles is larger than the aperture of the first through hole; a plurality of second particles are left in the second flow channel, and the particle size of the second particles is larger than the aperture of the second through hole; in the extraction stage, a first booster enters a first flow channel of the second substrate through a first feed inlet, and pushes first particles in the first flow channel to enter a first collection pool for collection and extraction of the first particles; and the second booster enters a second flow channel of the third substrate through a second feed inlet, and pushes second particles in the second flow channel to enter a second collection pool for collection and extraction of the second particles.

The invention also discloses a microfluidic device, which at least comprises a first substrate and a second substrate which are oppositely arranged; the first substrate is at least provided with a liquid inlet and a first feed inlet, and the liquid inlet and the first feed inlet both penetrate through the first substrate along the thickness direction of the first substrate; a first flow channel and a first collecting pool are formed in one side, facing the first substrate, of the second substrate, and a liquid inlet is communicated with the first flow channel; the first feeding hole is communicated with a first inlet end of the first flow channel, and the first collecting tank is communicated with a first outlet end of the first flow channel; the first inlet end and the first outlet end are two opposite ends of the first flow channel in the flow direction; the depth of the first flow channel is smaller than or equal to the thickness of the second substrate, a first thin film is arranged on one side, away from the first substrate, of the second substrate, the first thin film comprises any one of a photoinduced deformation thin film or an electrostrictive thin film, and the first thin film comprises a plurality of first sub-holes; when the depth of the first flow channel is smaller than the thickness of the second substrate, the first flow channel comprises a plurality of first through holes, and the first sub-holes are at least partially overlapped with the first through holes in the direction perpendicular to the plane of the second substrate; when the depth of the first flow channel is equal to the thickness of the second substrate, the orthographic projections of the plurality of first sub-holes to the second substrate are positioned in the first flow channel; the liquid inlet is used for flowing in a solution to be treated, and the first feeding hole is used for flowing in a first booster to push the solution in the first flow channel to flow into the first collecting tank.

Based on the same inventive concept, the invention also discloses a driving method of the microfluidic device, the driving method is used for driving the microfluidic device to work, and the driving method comprises the following steps: in the screening stage, the solution to be treated flows into the first flow channel of the second substrate from the liquid inlet, the aperture size of the first sub-hole of the first film is controlled through illumination or electrification, so that first particles with the particle size larger than that of the first sub-hole in the solution to be treated are left in the first flow channel, and the rest solution flows out of the first sub-hole; and in the extraction stage, the first booster enters the first flow channel of the second substrate through the first feed inlet, and pushes the first particles in the first flow channel to enter the first collection pool for collection and extraction of the first particles.

Compared with the prior art, the micro-fluidic device and the driving method thereof provided by the invention at least realize the following beneficial effects:

the micro-fluidic device of the invention can at least comprise a first substrate, a second substrate and a third substrate which are arranged in a stacking way, not only can the solution to be treated flow into the first flow channel of the second substrate from the liquid inlet, after the first-step screening is carried out through a plurality of first through holes arranged on the first flow passage, a plurality of first particles with the particle size larger than the aperture of the first through holes are remained in the first flow passage, the rest solution containing the particles smaller than or equal to the first through holes further flows into the second flow channel of the third substrate through the plurality of first through holes, and after the solution is screened again through the second through holes of the second flow channel, a plurality of second particles with the particle size larger than the aperture of the second through holes are remained in the second flow channel, the rest solution containing the particles smaller than or equal to the second through holes can further flow out for screening or recycling through the second through holes, so that the separation and screening of the cell particles with different sizes can be realized. The microfluidic device can also extract cell particles with different particle sizes after screening and separation, and the first boosting agent enters the first inlet end of the first flow channel of the second substrate through the first feed inlet, the first boosting agent can be specific solution or gas, and the specific solution or gas can boost the first particles which are remained in the first flow channel and have the particle sizes larger than the aperture of the first through hole to move, so that the first particles can flow from the first inlet end to the first outlet end of the first flow channel along the flow direction of the first flow channel and enter the first collection pool for collection and extraction. And the second assisting agent enters a second flow channel of the third substrate through a second feeding hole, and can assist to push second particles which are remained in the second flow channel and have the particle size larger than the aperture of the second through hole, so that the second particles can flow from a second inlet end to a second outlet end of the second flow channel along the flow direction of the second flow channel and enter a second collecting tank for collection and extraction. The invention can realize the screening and separation of the cell particles with different sizes through the first flow channel comprising the first through hole and the second flow channel comprising the second through hole, and can also realize the extraction and collection of the cell particles with different sizes after the screening and separation through the first collection pool on the second substrate and the second collection pool on the third substrate, and can improve the efficiency and reduce the cost while realizing the separation and extraction of the cell particles through a simple structure. The micro-fluidic device provided by the invention can also comprise a first substrate and a second substrate which are arranged oppositely, the size of the aperture of a first sub-hole on a first thin film arranged on one side of the second substrate far away from the first substrate is changed through electric control or light control, so that the screening and separation of cell particles with different sizes are realized, and the extraction and collection of the cell particles with different sizes after the screening and separation can be realized through a first collection pool on the second substrate, thereby being beneficial to reducing the whole thickness of the micro-fluidic device and realizing the effect of screening and extracting the cell particles with different sizes through the thinned micro-fluidic device.

Of course, it is not necessary for any product in which the present invention is practiced to specifically achieve all of the above-described technical effects simultaneously.

Other features of the present invention and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.

Fig. 1 is a schematic diagram of a disassembled structure of a microfluidic device according to an embodiment of the present invention;

FIG. 2 is a schematic view of the first substrate away from the second substrate in FIG. 1;

FIG. 3 is a schematic view of the second substrate facing the first substrate in FIG. 1;

FIG. 4 is a schematic view of the third substrate facing the second substrate in FIG. 1;

FIG. 5 is a top perspective view of the substrates of FIG. 1 after stacking;

FIG. 6 is a schematic sectional view taken along line A-A' of FIG. 5;

FIG. 7 is a schematic sectional view taken along line B-B' of FIG. 5;

fig. 8 is a schematic block diagram of a method of driving a microfluidic device according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of a first substrate of another microfluidic device provided in an embodiment of the present invention, the first substrate being away from a second substrate;

fig. 10 is a schematic structural diagram of a first substrate facing a second substrate of another microfluidic device according to an embodiment of the present invention;

fig. 11 is a schematic structural diagram of a second substrate facing a first substrate of another microfluidic device according to an embodiment of the present invention;

fig. 12 is a schematic view of another disassembled structure of the microfluidic device provided in the embodiments of the present invention;

FIG. 13 is a schematic view of the second substrate facing the first substrate in FIG. 12;

FIG. 14 is a schematic view of the third substrate facing the second substrate in FIG. 12;

fig. 15 is a schematic view of another disassembled structure of the microfluidic device provided in the embodiments of the present invention;

FIG. 16 is a schematic view of the structure of the side of the first substrate facing the second substrate in FIG. 15;

FIG. 17 is a schematic view of the second substrate facing the first substrate in FIG. 15;

FIG. 18 is a schematic view of the structure of the second substrate facing the third substrate in FIG. 15;

FIG. 19 is a schematic view of the third substrate facing the second substrate in FIG. 15;

fig. 20 is a schematic view of another disassembled structure of the microfluidic device provided in the embodiments of the present invention;

FIG. 21 is a top perspective view of the substrates of FIG. 20 after stacking;

FIG. 22 is a schematic cross-sectional view taken along line C-C' of FIG. 21;

fig. 23 is a schematic view of another disassembled structure of the microfluidic device provided in the embodiments of the present invention;

FIG. 24 is a top perspective view of the substrates of FIG. 23 after stacking;

FIG. 25 is a schematic cross-sectional view taken along line D-D' of FIG. 24;

FIG. 26 is a schematic view of another cross-sectional structure taken along line D-D' of FIG. 24;

fig. 27 is a schematic block diagram of another driving method of a microfluidic device according to an embodiment of the present invention;

fig. 28 is a schematic view of another disassembled structure of the microfluidic device provided in the embodiments of the present invention;

fig. 29 is a schematic view of another disassembled structure of the microfluidic device provided in the embodiments of the present invention;

fig. 30 is a schematic view of another disassembled structure of the microfluidic device provided in the embodiments of the present invention;

fig. 31 is a schematic view of another disassembled structure of the microfluidic device provided in the embodiments of the present invention;

fig. 32 is a schematic view of another disassembled structure of the microfluidic device provided in the embodiment of the present invention.

Detailed Description

Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

Referring to fig. 1 to 7 in combination, fig. 1 is a schematic diagram illustrating a split structure of a microfluidic device according to an embodiment of the present invention, fig. 2 is a schematic diagram illustrating a side of a first substrate away from a second substrate in fig. 1, fig. 3 is a schematic diagram illustrating a side of the second substrate facing the first substrate in fig. 1, fig. 4 is a schematic diagram illustrating a side of a third substrate facing the second substrate in fig. 1, fig. 5 is a top perspective view of the substrates in fig. 1 after being stacked, fig. 6 is a schematic diagram illustrating a cross-sectional structure of a direction a-a 'in fig. 5, fig. 7 is a schematic diagram illustrating a cross-sectional structure of a direction B-B' in fig. 5 (it can be understood that, in order to clearly illustrate the structures of the substrates in the embodiment, the structures in the figures are all transparent), and a microfluidic device 000 according to an embodiment of the present invention at least includes a first substrate 10, a second substrate 20, and a stacked structure, A third substrate 30;

the first substrate 10 is at least provided with a liquid inlet 10A, a first feed port 101 and a second feed port 102, and the liquid inlet 10A, the first feed port 101 and the second feed port 102 all penetrate through the first substrate 10 along the thickness direction of the first substrate 10;

a first flow channel 201 and a first collecting tank 202 are formed on one side of the second substrate 20 facing the first substrate 10, and the depth of the first flow channel 201 is smaller than the thickness of the second substrate 20; the liquid inlet 10A is communicated with a first flow channel 201, the first feed inlet 101 is communicated with a first inlet end 201A of the first flow channel 201, and the first collecting tank 202 is communicated with a first outlet end 201B of the first flow channel 201; wherein, the first inlet end 201A and the first outlet end 201B are opposite ends of the first flow channel 201 in the flowing direction thereof;

a second flow channel 301 and a second collecting tank 302 are formed on one side of the third substrate 30 facing the second substrate 20, and the depth of the second flow channel 302 is smaller than the thickness of the third substrate 30; the first flow channel 201 is communicated with the second flow channel 301, the second feed inlet 102 is communicated with a second inlet end 301A of the second flow channel 301, and the second collecting tank 302 is communicated with a second outlet end 301B of the second flow channel 301; wherein the second inlet end 301A and the second outlet end 301B are opposite ends of the second flow channel 301 in the flow direction thereof;

the first flow channel 201 comprises a plurality of first through holes 2011, the second flow channel 301 comprises a plurality of second through holes 3011, and the diameter of the first through holes 2011 is larger than that of the second through holes 3011 in the direction Z perpendicular to the plane of the first substrate 10;

the liquid inlet 10A is used for flowing a solution to be treated, the first feeding hole 101 is used for flowing a first boosting agent to push the solution in the first flow channel 201 to flow into the first collecting tank 202, and the second feeding hole 102 is used for flowing a second boosting agent to push the solution in the second flow channel 301 to flow into the second collecting tank 302.

Specifically, the microfluidic device 000 of the present embodiment can be used in the disciplines of chemistry, fluid physics, microelectronics, new materials, biology and biomedical engineering to realize the separation and extraction operations of cells (microbeads) of different sizes. The microfluidic device 000 may include at least a first substrate 10, a second substrate 20, and a third substrate 30 stacked in layers, and optionally, the first substrate 10 may be an uppermost substrate, and the second substrate 20 and the third substrate 30 are sequentially stacked below the first substrate 10. The first substrate 10 is provided with at least a liquid inlet 10A, a first inlet 101 and a second inlet 102 (it is understood that the positions and sizes of the liquid inlet 10A, the first inlet 101 and the second inlet 102 on the first substrate 10 are only exemplarily shown in the figure, and do not represent the actual situation, and in the specific implementation, the positions and sizes may be set according to the actual requirements), the liquid inlet 10A, the first inlet 101 and the second inlet 102 all penetrate through the first substrate 10 along the thickness direction of the first substrate 10, namely, the liquid inlet 10A, the first feed inlet 101 and the second feed inlet 102 which are arranged on the first substrate 10 are all communicated with the second substrate 20 or the third substrate 30 which is arranged below the first feed inlet, so that the solution or gas flowing through the loading port 10A, the first loading port 101, and the second loading port 102 can smoothly flow into the second substrate 20 or the third substrate 30 by its own weight.

In this embodiment, a first flow channel 201 is formed on a side of the second substrate 20 facing the first substrate 10, the first flow channel 201 is formed by a depression of a surface of the second substrate 20 close to the first substrate 10 and facing a side away from the first substrate 10, and a depth of the first flow channel 201 is smaller than a thickness of the second substrate 20 (as shown in fig. 6), since the liquid inlet 10A is communicated with the first flow channel 201 (a communication relationship thereof is indicated by a dotted line in fig. 1), a solution to be processed by the microfluidic device 000 entering from the liquid inlet 10A can smoothly enter the first flow channel 201 of the second substrate 20, and a first screening separation is performed through the plurality of first through holes 2011 formed in the first flow channel 201, that is, after the solution to be processed by the microfluidic device 000 flows into the first flow channel 201 through the liquid inlet 10A, particles larger than the first through holes 2011 in the solution to be processed are retained in the first flow channel 201, and the remaining solution including particles smaller than or equal to the first through holes 2011 further passes through the plurality of first through the first through holes 2011 And then flows into the second channel 301 of the third substrate 30.

In this embodiment, the second flow channel 301 is formed on a side of the third substrate 30 facing the second substrate 20, the second flow channel 301 is formed by a depression of a surface of the third substrate 30 close to the second substrate 20 and facing a side far from the second substrate 20, and a depth of the second flow channel 301 is smaller than a thickness of the third substrate 30 (as shown in fig. 7), since the first flow channel 201 is communicated with the second flow channel 301 (a communication relationship thereof is indicated by a dotted line in fig. 1), a solution remaining after being screened by the plurality of first through holes 2011 of the first flow channel 201 can enter the second flow channel 301 of the third substrate 30, and is further screened and separated by the plurality of second through holes 3011 formed in the second flow channel 301, that is, after a solution to be processed by the microfluidic device 000 flows into the first flow channel 201 through the liquid inlet 10A, particles larger than the first through holes 2011 in the solution to be processed are retained in the first flow channel 201, and a remaining solution including particles smaller than or equal to the first through holes 2011 can further continue to pass through the plurality of first through holes 2011 The particles flowing into the second channel 301 of the third substrate 30 and larger than the second through holes 3011 remain in the second channel 301, and the rest of the solution including the particles smaller than or equal to the second through holes 3011 further flows out of the second through holes 3011 for screening (if the substrate with through holes smaller than the second through holes 3011 is further disposed below the third substrate 30) or is recycled, thereby realizing separation and screening of cell particles with different sizes.

In this embodiment, a first collecting pool 202 is further disposed on a side of the second substrate 20 facing the first substrate 10, the first collecting pool 202 is formed by a surface of the second substrate 20 close to the first substrate 10 and recessed towards a side far from the first substrate 10, since the first feeding hole 101 is communicated with a first inlet end 201A of the first flow channel 201 (the communication relationship is indicated by a dotted line in fig. 1), the first collecting pool 202 is communicated with a first outlet end 201B of the first flow channel 201, where the first inlet end 201A and the first outlet end 201B are opposite ends of the first flow channel 201 in a flowing direction (e.g. a first direction X in the figure), a first assisting agent can enter the first flow channel 201 of the second substrate 20 through the first feeding hole 101, the first assisting agent can be a specific solution or gas, and the specific solution or gas can assist to push particles having a particle diameter larger than a pore diameter of the first through hole 201 and remaining in the first flow channel 201, so that it can flow from the first inlet end 201A to the first outlet end 201B of the first flow channel 201 along the flow direction (first direction X) of the first flow channel 201, and enter the first collection tank 202 for collection and extraction.

Alternatively, the depth of the first collection chamber 202 may be smaller than the thickness of the second substrate 20 (as shown in fig. 6), so that the cell particles collected in the first collection chamber 202 can be stored in the first collection chamber 202, which facilitates the next operation. Alternatively, the depth of the first collection pool 202 may be equal to the thickness of the second substrate 20, and the first collection pool 202 may be directly connected to an external first collection bottle or other storage device (not shown in the drawings), so as to facilitate collection and extraction of the cell particles screened and separated through the first through-hole 2011. The subsequent disposal manner of the cellular particles collected in the first collection pool 202 is not particularly limited in this embodiment, and the subsequent disposal manner may be selected according to actual requirements.

In this embodiment, a second collecting tank 302 is further disposed on a side of the third substrate 30 facing the second substrate 20, the second collecting tank 302 is formed by recessing a surface of the third substrate 30 close to the second substrate 20 toward a side far from the second substrate 20, and since the second feed inlet 102 is communicated with a second inlet end 301A of the second flow channel 301 (the communication relationship is illustrated by a dotted line in fig. 1), the second collecting tank 302 is communicated with a second outlet end 301B of the second flow channel 301, optionally, a through hole 20A (as shown in fig. 3) may be disposed on the second substrate 20, and the through hole 20A is used for communicating the second feed inlet 102 of the first substrate 10 with the second inlet end 301A of the second flow channel 301 of the third substrate 30; the second inlet end 301A and the second outlet end 301B are opposite ends of the second flow channel 301 in the flowing direction (e.g., the first direction X in the figure), the second assisting agent can be introduced into the second flow channel 301 of the third substrate 30 through the second inlet 102, the second assisting agent can be a specific solution or gas, and the specific solution or gas can assist in pushing the particles with a larger diameter than the second through hole 3011, which remain in the second flow channel 301, so that the particles can flow from the second inlet end 301A to the second outlet end 301B of the second flow channel 301 along the flowing direction (the first direction X) of the second flow channel 301, and enter the second collection pool 302 for collection and extraction.

Alternatively, the depth of second collection well 302 may be less than the thickness of third substrate 30 (as shown in fig. 7), so that the cell particles collected in second collection well 302 can be stored in second collection well 302, which facilitates the next operation. Alternatively, the depth of the second collecting tank 302 may be equal to the thickness of the third substrate 30, and the second collecting tank 302 may be directly connected to an external second collecting bottle or other storage device (not shown in the drawings), so as to facilitate collection and extraction of the cell particles screened and separated by the second through hole 3011. The subsequent disposal manner of the cell particles collected in the second collection pool 302 is not particularly limited in this embodiment, and in the specific implementation, the arrangement may be selected according to actual requirements.

In the micro-fluidic device 000 provided in this embodiment, the side of the second substrate 20 facing the first substrate 10 is provided with the first flow channel 201 and the first collection pool 202, the side of the third substrate 30 facing the second substrate 20 is provided with the second flow channel 301 and the second collection pool 302, the first flow channel 201 includes the plurality of first through holes 2011, the second flow channel 301 includes the plurality of second through holes 3011, in the direction Z perpendicular to the plane of the first substrate 10, the aperture of the first through holes 2011 is larger than that of the second through holes 3011, the first flow channel 201 including the first through holes 2011 and the second flow channel 301 including the second through holes 3011 can respectively realize screening and separation of cellular microparticles with different sizes, and the first collection pool 202 on the second substrate 20 and the second collection pool 302 on the third substrate 30 can also realize extraction and collection of cellular microparticles with different sizes after screening and separation, not only can realize separation and extraction of cellular microparticles by a simple structure, the micro-fluidic device 000 of the embodiment may also improve efficiency and reduce cost, and since the micro-fluidic device 000 at least includes the first substrate 10, the second substrate 20, and the third substrate 30 bonded and sealed to each other, the solutions to be processed all flow in the flow channels of the substrates, and are collected and extracted via the collection pool, the risk of contamination may be reduced.

It should be noted that, in this embodiment, the structure of the microfluidic device 000 is illustrated by only three substrates stacked in layers, and does not show the actual number of the substrates in the microfluidic device 000, in a specific implementation, the number of the substrates in the microfluidic device 000 may be N (N is a positive integer greater than or equal to 3), at this time, N inlets penetrating the thickness of the first substrate 10 may be disposed on the first substrate 10 as the uppermost layer, one of the inlets may be a liquid inlet for a solution to be processed, and the remaining inlets may be used as liquid inlet for a booster agent and are respectively communicated with different substrates below the first substrate 10, so as to implement screening, separation, extraction and collection of cell particles with different sizes.

It should be further noted that, in the present embodiment, the shape of the first through-hole 2011 and the second through-hole 3011 are only exemplified as circles, and do not represent actual shapes thereof, and in the specific implementation, the arrangement may be selected according to the shape of the cell particles to be screened and extracted.

In some alternative embodiments, please refer to fig. 1-7 and 8 in combination, fig. 8 is a schematic diagram of a driving method of a microfluidic device according to an embodiment of the present invention, the driving method is used for driving the above microfluidic device to operate, and the driving method includes: in the screening stage T1, the solution to be processed flows into the first flow channel 201 of the second substrate 20 from the liquid inlet 10A, enters the second flow channel 301 of the third substrate 30 after being screened by the first through hole 2011 of the first flow channel 201, and is screened again by the second through hole 3011 of the second flow channel 301; at this time, a plurality of first particles are remained in the first flow channel 201, and the particle size of the first particles is larger than the aperture of the first through-hole 2011; a plurality of second particles are remained in the second flow channel 301, and the particle size of the second particles is larger than the pore size of the second through hole 3011; it is understood that when the first particles and the second particles have a regular shape such as a spherical shape, the particle diameters of the first particles and the second particles are spherical diameters, and when the first particles and the second particles have an ellipsoidal shape, the particle diameters of the first particles and the second particles are the maximum length in the major axis direction; when the first and second particles are irregularly shaped, the particle size of the first and second particles is the length of the line between the two farthest points on the surface of the particles. In the extraction stage T2, the first assisting agent enters the first flow channel 201 of the second substrate 20 through the first feeding hole 101, and pushes the first particles in the first flow channel 201 to enter the first collecting pool 202, so as to collect and extract the first particles; the second assisting agent enters the second flow channel 301 of the third substrate 30 through the second feeding hole 102, and pushes the second particles in the second flow channel 301 to enter the second collecting pool 302, so as to collect and extract the second particles.

Specifically, the driving method for driving the operation of the microfluidic device 000 of the present embodiment may include a screening stage and an extraction stage. In the screening stage T1, the solution to be processed may flow into the first flow channel 201 of the second substrate 20 from the loading port 10A, and after a first step of screening is performed through the plurality of first through holes 2011 formed in the first flow channel 201, the plurality of first particles may remain in the first flow channel 201, the particle size of the first particles is larger than the pore size of the first through holes 2011, the remaining solution including the particles smaller than or equal to the first through holes 2011 may further flow into the second flow channel 301 of the third substrate 30 through the plurality of first through holes 2011, after re-screening is performed through the second through holes 3011 of the second flow channel 301, the plurality of second particles may remain in the second flow channel 301, the particle size of the second particles is larger than the pore size of the second through holes 3011, the remaining solution including the particles smaller than or equal to the second through holes 3011 may further flow out through the plurality of second through holes 3011 for screening (if a substrate with through holes smaller than the pore size of the second through holes 3011 is further disposed below the third substrate 30) or may be recovered, thereby realizing the separation and screening of the cell particles with different sizes.

In the extraction stage T2, the first assisting agent enters the first inlet end 201A of the first flow channel 201 of the second substrate 20 through the first inlet 101, and the first assisting agent may be a specific solution or gas, and the specific solution or gas may assist to push the first particles with a diameter larger than the diameter of the first through holes 2011 remaining in the first flow channel 201 to move, so that the first particles can flow from the first inlet end 201A to the first outlet end 201B of the first flow channel 201 along the flow direction (the first direction X) of the first flow channel 201 and enter the first collection pool 202 for collection and extraction. And the second assisting agent enters the second flow channel 301 of the third substrate 30 through the second feeding hole 102, and the second assisting agent may be a specific solution or gas, and the specific solution or gas may assist to push the second particles, which are left in the second flow channel 301 and have a larger diameter than the second through hole 3011, so that the second particles can flow from the second inlet end 301A to the second outlet end 301B of the second flow channel 301 along the flow direction (the first direction X) of the second flow channel 301, and enter the second collecting pool 302 for collection and extraction. The driving method of the microfluidic device provided by the embodiment can be applied to the microfluidic device in the above embodiment to separate and extract cellular particles with different sizes, and not only has high working efficiency, simple operation and low cost, but also can reduce the risk of contamination of the cellular particles.

In some optional embodiments, please refer to fig. 1 to fig. 7 continuously, in this embodiment, the liquid inlet 10A of the first substrate 10 is communicated with the first flow channel 201 through the first inlet section 100, and optionally, the first inlet section 100 is communicated with the first flow channel 201 close to the first outlet end 201B, which is taken as an example for illustration, but does not represent an actual setting position, and in a specific implementation, the position of the first inlet section 100 may be designed according to actual requirements; the orthographic projection of the first inlet section 100 to the first substrate 10 is overlapped with the liquid inlet 10A; the first inlet section 100 is located on the side of the second substrate 20 facing the first substrate 10.

This embodiment illustrates that the loading port 10A provided on the first substrate 10 and the first flow channel 201 on the side of the second substrate 20 facing the first substrate 10 can communicate with each other through a first inlet section 100 overlapping with the loading port 10A; alternatively, as shown in fig. 1 and fig. 3, the first inlet section 100 may be formed on a side surface of the second substrate 20 facing the first substrate 10, and only after the first substrate 10 and the second substrate 20 are stacked, the liquid inlet 10A on the first substrate 10 and the first inlet section 100 on the second substrate 20 are overlapped and communicated. After the first substrate 10 and the second substrate 20 are stacked, the solution to be processed flowing in through the liquid inlet 10A first passes through the first inlet section 100 on the second substrate 20 and then flows into the first flow channel 201 on the second substrate 20 for the first step of particle screening and separation.

In some alternative embodiments, as shown in fig. 1 and 4, the second flow channel 301 on the third substrate 30 communicates with the first flow channel 201 through the second inlet section 200, and the orthographic projection of the second inlet section 200 to the second substrate 20 overlaps with the first flow channel 201; the second inlet section 200 is located on the side of the third base plate 30 facing the second base plate 20. Optionally, the second inlet section 200 may also be disposed on a side of the second substrate 20 facing the third substrate 30, at this time, an orthographic projection of the second inlet section 200 disposed on the lower surface of the second substrate 20 on the third substrate 30 may overlap with the second flow channel 301, the position of the second inlet section 200 is not particularly limited in this embodiment, and in the specific implementation, the second inlet section may be selectively disposed according to actual requirements.

This embodiment illustrates that the second flow channel 301 opened on the third substrate 30 and the first flow channel 201 on the second substrate 20 can communicate with each other through a second inlet section 200 overlapping the first flow channel 201; the second inlet section 200 may be formed on a side surface of the third substrate 30 facing the second substrate 20, and only after the second substrate 20 and the third substrate 30 are stacked, the first flow channel 201 on the second substrate 20 and the second inlet section 200 on the third substrate 30 are overlapped and communicated, when the first substrate 10, the second substrate 20 and the third substrate 30 are stacked, the solution to be processed flowing in through the liquid inlet 10A firstly passes through the first inlet section 100 on the second substrate 20 and then flows into the first flow channel 201 on the second substrate 20 for the first-step particle screening and separation, and then flows into the second inlet section 200 of the third substrate 30 from the first through hole 2011 on the second substrate 20, and then continues to flow into the second flow channel 301 communicated with the second inlet section 200, and continues to screen and separate the particles through the second through hole 3011 in the second flow channel 301. The second inlet section 200 without the through hole in this embodiment is disposed to avoid direct impact of the solution screened by the first flow channel 201 on the second flow channel 301.

In some alternative embodiments, please refer to fig. 9-11 in combination, fig. 9 is a schematic structural diagram of a side of a first substrate of another microfluidic device provided by an embodiment of the present invention, which is away from a second substrate, fig. 10 is a schematic structural diagram of a side of the first substrate of another microfluidic device provided by an embodiment of the present invention, which is facing the second substrate (fig. 10 is equivalent to the bottom view of fig. 9), fig. 11 is a schematic structural diagram of a side of the second substrate of another microfluidic device provided by an embodiment of the present invention, which is facing the first substrate (it can be understood that structures of the substrates of this embodiment are illustrated in transparent for clarity), this embodiment explains that a liquid inlet 10A formed on the first substrate 10 and a first flow channel 201 of a side of the second substrate 20 facing the first substrate 10 can communicate with each other through a first inlet section 100 overlapping with the liquid inlet 10A, the first inlet section 100 may be disposed at a side of the first substrate 10 facing the second substrate 20; the first inlet section 100 may be formed on a side surface of the first substrate 10 facing the second substrate 20, and only needs to satisfy that the liquid inlet 10A on the first substrate 10 and the first inlet section 100 on the second substrate 20 are overlapped and communicated after the first substrate 10 and the second substrate 20 are overlapped. After the first substrate 10 and the second substrate 20 are stacked, the solution to be processed flowing in through the liquid inlet 10A first passes through the first inlet section 100 of the first substrate 10 near the second substrate 20 and then flows into the first flow channel 201 on the second substrate 20 to perform the first step of particle screening and separation.

In some alternative embodiments, please refer to fig. 12-14 in combination, fig. 12 is another schematic diagram of a disassembled structure of a microfluidic device according to an embodiment of the present invention, fig. 13 is a schematic diagram of a side of the second substrate facing the first substrate in fig. 12, fig. 14 is a schematic diagram of a side of the third substrate facing the second substrate in fig. 12 (it is understood that structures of the substrates in this embodiment are illustrated in a transparent manner for clarity), in this embodiment, a liquid inlet 10A formed on the first substrate 10 and a first flow channel 201 formed on a side of the second substrate 20 facing the first substrate 10 may be communicated with each other through a first inlet section 100 overlapping with the liquid inlet 10A, and the first inlet section 100 is provided with a first valve K1.

In this embodiment, it is explained that the first valve K1 is disposed on the first inlet section 100, so that whether the first inlet section 100 is conducted or not can be controlled by opening and closing the first valve K1, and further whether the liquid inlet 10A on the first substrate 10 is communicated with the first flow channel 201 on the second substrate 20 is controlled, so as to achieve flexible control of cell particle manipulation.

Optionally, as shown in fig. 12 and 13, the first outlet end 201B of the first flow channel 201 of the present embodiment is communicated with the first collecting tank 202 through a second valve K2, and the first feeding hole 101 is communicated with the first inlet end 201A of the first flow channel 201 through a third valve K3; the second valve K2 may be disposed at the first outlet end 201B of the first flow path 201, and the third valve K3 may be disposed at the first inlet end 201A of the first flow path 201;

alternatively, as shown in fig. 12 and 14, the second outlet end 301B of the second flow channel 301 of the present embodiment is communicated with the second collecting tank 302 through a fourth valve K4, and the second feeding hole 102 is communicated with the second inlet end 301A of the second flow channel 301 through a fifth valve K5; the fourth valve K4 may be disposed at the second outlet end 301B of the second flow path 301, and the fifth valve K5 may be disposed at the second inlet end 301A of the second flow path 301.

In this embodiment, it is explained that the first outlet end 201B and the first inlet end 201A of the first flow channel 201 may be provided with a valve for controlling conduction, and similarly, the second outlet end 301B and the second inlet end 301A of the second flow channel 301 may also be provided with a valve for controlling conduction. When the solution to be treated completes the screening separation work in the first flow path 201 and the second flow path 301 to enter the particle extraction stage, the first valve K1 of the first inlet section 100 can be closed, and the second valve K2 and the third valve K3 can be opened, wherein the first inlet 101 is connected to the first flow channel 201 and the first collecting tank 202, the first assisting agent enters the first inlet end 201A of the first flow channel 201 of the second substrate 20 through the first inlet 101, the first assisting agent can be a specific solution or gas, the specific solution or gas can assist to push the first particles with a diameter larger than the aperture of the first through-hole 2011 and remaining in the first flow channel 201 to move, so that the first particles can flow along the flow direction (the first direction X) of the first flow channel 201 from the first inlet end 201A to the first outlet end 201B of the first flow channel 201, and enter the first collection pool 202 to collect and extract the first particles. If it is desired to collect and extract the second particles remaining in the second flow channel 301, the first valve K1 on the first inlet section 100 is closed, the second valve K2 and the third valve K3 are closed, the fourth valve K4 and the fifth valve K5 are opened, the second inlet 102 is communicated with the second flow channel 301 and the second collecting tank 302, the second assisting agent enters the second flow channel 301 of the third substrate 30 through the second inlet 102, the second assisting agent may be a specific solution or gas, and the specific solution or gas may assist to push the second particles remaining in the second flow channel 301 and having a larger diameter than the second through hole 3011, so that the second particles can flow from the second inlet 301A to the second outlet 301B of the second flow channel 301 along the flow direction (the first direction X) of the second flow channel 301 and enter the second collecting tank 302 to collect and extract the second particles. The driving method of the microfluidic device provided by the embodiment can be applied to the microfluidic device in the above embodiment to separate and extract cell particles with different sizes, and can also flexibly control the separation and extraction operation to be performed and stopped through each valve, so that the operation is simple and flexible, and the working efficiency is high.

Optionally, in this embodiment, the manufacturing materials of the first valve K1, the second valve K2, the third valve K3, the fourth valve K4, and the fifth valve K5 include any one of a photo-deformable material and an electro-deformable material.

When the first valve K1, the second valve K2, the third valve K3, the fourth valve K4 and the fifth valve K5 are made of a photo-deformable material, such as a film-shaped micro-valve structure made of azobenzene, diarylhydrocarbon, styrene, spiropyran and derivatives thereof, the first valve K1, the second valve K2, the third valve K3, the fourth valve K4 and the fifth valve K5 made of the photo-deformable material can be directly attached to respective required positions, when the pipeline communication needs to be controlled, the selective and reversible reconstitution of the first valve K1 made of the photo-deformable material can be realized through light treatment (such as whether the light is irradiated or not), so that the valve can be opened and closed, and when the valve is not irradiated, the pipeline where the valve is positioned can be contracted so that the pipeline where the valve is positioned can be opened; or the valve shrinks when being illuminated, so that the pipeline where the valve is located is opened, and expands when being not illuminated so that the pipeline where the valve is located is closed, and during specific implementation, the valve can be arranged to expand or contract when being illuminated according to the property of a specific photoinduced deformation material.

It should be understood that the present embodiment is only an exemplary illustration of the structural shape of the valves, and in practical implementation, the structure of each valve can be designed according to the shape and size of the first inlet section 100, the first flow passage 201, and the second flow passage 301, and it is only necessary that the first valve K1 can control the conduction or non-conduction of the first inlet section 100 and the first flow passage 201 through expansion or contraction, the second valve K2 can control the conduction or non-conduction of the first collecting tank 202 and the first outlet end 201B of the first flow passage 201 through expansion or contraction, the third valve K3 can control the conduction or non-conduction of the first inlet 101 and the first inlet end 201A of the first flow passage 201 through expansion or contraction, the fourth valve K4 can control the conduction or non-conduction of the second collecting tank 302 and the second outlet end 301B of the second flow passage 301 through expansion or contraction, and the fifth valve K5 can control the conduction or non-conduction of the second inlet 102 and the second inlet end 301A of the second flow passage 301 through expansion or contraction, the present embodiment is not particularly limited.

In some alternative embodiments, please refer to fig. 15-19 in combination, fig. 15 is another schematic diagram of a disassembled structure of a microfluidic device according to an embodiment of the present invention, fig. 16 is a schematic diagram of a side of a first substrate facing a second substrate in fig. 15, fig. 17 is a schematic diagram of a side of the second substrate facing the first substrate in fig. 15, fig. 18 is a schematic diagram of a side of the second substrate facing a third substrate in fig. 15, and fig. 19 is a schematic diagram of a side of the third substrate facing the second substrate in fig. 15 (it is understood that structures of the substrates in this embodiment are illustrated for clarity, structures in the drawings are illustrated in a transparent manner, and the valves and the electrode leads are filled in a transparent manner in fig. 1), in this embodiment, when a manufacturing material of the first valve K1 is an electro-deformable material, the first valve K1 is connected to a first electrode lead L1, and optionally, the first electrode lead L1 may include two leads, that is, both ends of the first valve K1 are connected with first electrode leads L11 and L12, respectively.

This embodiment explains that if the first valve K1 is made of an electro-deformable material, such as an electro-expandable colloidal crystal thin film (reactant of monodisperse polystyrene microspheres and ferrocene derivatives, etc.), the first valve K1 needs to be connected to the first electrode lead L1, optionally, two ends of the first valve K1 are respectively connected to the first electrode leads L11 and L12, the first electrode leads L11 and L12 are respectively used to connect external control signals with different values to two ends of the first valve K1, so that the external control signals are respectively transmitted to the first valve K1 of the electro-deformable material through the first electrode leads L11 and L12, a voltage difference is formed between two ends of the first valve K1, so as to control whether the first valve K1 is opened or not through the driving electrical signal, for example, when the first inlet section 100 needs to be communicated with the first flow channel 201, the first valve K1 of the electro-deformable material can be selectively reconfigured by electrical processing (e.g. powering on or not), the first valve K1 functions as a valve switch, and expands when the first electrode leads L11 and L12 are energized, thereby closing the pipe in which it is located, and contracts when the first electrode leads L11 and L12 are not energized, thereby opening the pipe in which it is located; or the first valve K1 may be contracted when the first electrode leads L11 and L12 are energized, so as to open the pipe where the first valve K is located, and may be expanded when the first electrode leads L11 and L12 are not energized, so as to close the pipe where the first valve K1 is located.

Alternatively, as shown in fig. 15-19, in this embodiment, the second valve K2, the third valve K3, the fourth valve K4, and the fifth valve K5 may also be made of an electro-deformable material, in this case, the second valve K2 is connected to the second electrode lead L2, the third valve K3 is connected to the third electrode lead L3, the fourth valve K4 is connected to the fourth electrode lead L4, and the fifth valve K5 is connected to the fifth electrode lead L5, optionally, the second electrode lead L2 may include two, that is, two ends of the second valve K2 are connected to the second electrode leads L21 and L22, the third electrode lead L3 may include two, that is, two ends of the third valve K3 are connected to the third electrode leads L31 and L32, the fourth electrode lead L4 may include two, that is two ends of the fourth valve K4 are connected to the fourth electrode leads L41 and L42, and the fifth valve K5 may include two electrodes L395392, namely, the fifth valve K5 has fifth electrode leads L51 and L52 connected to both ends thereof, respectively. The second electrode leads L21 and L22 are used for respectively accessing different external control signals to two ends of the second valve K2, the third electrode leads L31 and L32 are used for respectively accessing different external control signals to two ends of the third valve K3, the fourth electrode leads L41 and L42 are used for respectively accessing different external control signals to two ends of the fourth valve K4, and the fifth electrode leads L51 and L52 are used for respectively accessing different external control signals to two ends of the fifth valve K5, that is, the materials of the valves in this embodiment may all adopt an electro-deformable material, and the electrode leads for accessing external control signals are connected to two ends of each valve, so as to realize the switching function of the valves.

Alternatively, as shown in fig. 15 to 19, the first electrode lead L1 and the first valve K1 in the present embodiment are disposed on a side of the first substrate 10 facing the second substrate 20;

the second electrode lead L2 and the second valve K2 are disposed at a side of the first substrate 10 facing the second substrate 20; a third electrode lead L3 and a third valve K3 are disposed on a side of the first substrate 10 facing the second substrate 20;

the fourth electrode lead L4 and the fourth valve K4 are disposed at a side of the second substrate 20 facing the third substrate 30; the fifth electrode lead L5 and the fifth valve K5 are disposed at a side of the second substrate 20 facing the third substrate 30.

This embodiment explains that when the first valve K1, the second valve K2, the third valve K3, the fourth valve K4 and the fifth valve K5 are made of an electro-deformable material, the first valve K1 is connected with the first electrode lead L1, the second valve K2 is connected with the second electrode lead L2, the third valve K3 is connected with the third electrode lead L3, the fourth valve K4 is connected with the fourth electrode lead L4, the fifth valve K5 is connected with the fifth electrode lead L5, the first inlet section 100 acting on the second substrate 20 and the first valve K1, the second valve K2, the third valve K3, the first electrode lead L1, the second electrode lead L2 and the third electrode lead L3 in the first flow channel 201 can be made on the surface of the first substrate 10 facing the second substrate 20, and the first inlet section 100 and the first flow channel 201 are mainly formed on the surface of the second substrate 20 facing the first substrate 10 by etching process, Since the first collecting chamber 202 and the valves and the electrode leads are mainly made of conductive materials through an attaching or depositing process, if the valves and the electrode leads are still formed on the surface of the second substrate 20 facing the first substrate 10, the performance of the deposited or attached valves and electrode leads may be affected due to the uneven surface of the second substrate 20 facing the first substrate 10, and the yield may be reduced. Therefore, in the embodiment, the first valve K1, the second valve K2, the third valve K3, the first electrode lead L1, the second electrode lead L2 and the third electrode lead L3 which are made of conductive materials through an attaching or depositing process are arranged on the flat surface of the side of the first substrate 10 facing the second substrate 20, and the first flow channel 201, the first inlet section 100 and the first collection pool 202 are formed on the surface of the side of the second substrate 20 facing the first substrate 10 through an etching process, so that the influence of the uneven surface of the side of the second substrate 20 facing the first substrate 10 on the performances of the valves and the electrode leads can be avoided, and the manufacturing yield can be improved. Similarly, the fourth electrode lead L4, the fourth valve K4, the fifth electrode lead L5 and the fifth valve K5 which are made of conductive materials through an attaching or depositing process are made on the flat surface of one side of the second substrate 20 facing the third substrate 30, and the surface of one side of the third substrate 30 facing the second substrate 20 is specially formed into the second flow channel 301, the second inlet section 200 and the second collecting tank 302 through an etching process, so that the influence of the uneven surface of one side of the third substrate 30 facing the second substrate 20 on the performances of the valves and the electrode leads can be avoided, and the improvement of the manufacturing yield is facilitated.

In some alternative embodiments, please refer to fig. 20-22 in combination, fig. 20 is a schematic diagram of another split structure of a microfluidic device according to an embodiment of the present invention, fig. 21 is a top perspective view of the substrates in fig. 20 after being stacked, fig. 22 is a schematic diagram of a cross-sectional structure along the direction C-C' in fig. 21 (it is understood that structures of the substrates in this embodiment are illustrated in a transparent manner for clarity), and a microfluidic device 000 according to this embodiment includes at least a first substrate 10 and a second substrate 20 that are disposed opposite to each other;

the first substrate 10 is at least provided with a liquid inlet 10A and a first feed inlet 101, and the liquid inlet 10A and the first feed inlet 101 both penetrate through the first substrate 10 along the thickness direction of the first substrate 10;

a first flow channel 201 and a first collecting tank 202 are arranged on one side of the second substrate 20 facing the first substrate 10, and the liquid inlet 10A is communicated with the first flow channel 201; the first feed port 101 is communicated with a first inlet end 201A of the first flow channel 201, and the first collecting tank 202 is communicated with a first outlet end 201B of the first flow channel 201; the first inlet end 201A and the first outlet end 201B are opposite ends of the first flow channel 201 in the flow direction;

the depth of the first flow channel 201 is smaller than the thickness of the second substrate 20, a first thin film 40 is arranged on one side of the second substrate 20 away from the first substrate 10, the first thin film 40 comprises any one of a photo-induced deformation thin film or an electro-induced deformation thin film, and the first thin film 40 comprises a plurality of first sub-holes 401;

the first flow channel 201 includes a plurality of first through holes 2011, and the first sub-apertures 401 at least partially overlap the first through holes 2011 in a direction Z perpendicular to a plane of the second substrate 20;

the liquid inlet 10A is used for flowing a solution to be treated, and the first inlet 101 is used for flowing a first assisting agent to push the solution in the first flow channel 201 to flow into the first collecting tank 202.

Specifically, the microfluidic device 000 of the present embodiment can be used in the disciplines of chemistry, fluid physics, microelectronics, new materials, biology and biomedical engineering to realize the separation and extraction operations of cells (microbeads) of different sizes. The microfluidic device 000 may include at least a first substrate 10 and a second substrate 20 stacked, and optionally, the first substrate 10 may be an upper substrate and the second substrate 20 may be a lower substrate. The first substrate 10 is at least provided with a liquid inlet 10A and a first feed inlet 101 (it can be understood that the positions and sizes of the liquid inlet 10A and the first feed inlet 101 on the first substrate 10 are only exemplarily shown in the drawing, and do not represent actual situations, and in specific implementation, the positions and sizes can be set according to actual requirements), the liquid inlet 10A and the first feed inlet 101 both penetrate through the first substrate 10 along the thickness direction of the first substrate 10, that is, the liquid inlet 10A and the first feed inlet 101 provided on the first substrate 10 are both communicated with the second substrate 20 below the same, so that substances such as solution or gas flowing in through the liquid inlet 10A and the first feed inlet 101 can smoothly flow into the second substrate 20 through self gravity.

In this embodiment, the first flow channel 201 is formed on the side of the second substrate 20 facing the first substrate 10, the first flow channel 201 is formed by recessing the surface of the second substrate 20 close to the first substrate 10 toward the side far from the first substrate 10, and the depth of the first flow channel 201 is smaller than the thickness of the second substrate 20 (as shown in fig. 22), and since the liquid inlet 10A is communicated with the first flow channel 201 (the communication relationship is indicated by a dotted line in fig. 20), the solution to be processed by the microfluidic device 000 entering from the liquid inlet 10A can smoothly enter the first flow channel 201 of the second substrate 20, and enter the first sub-hole 401 of the first thin film 40 through the plurality of first through holes 2011 formed in the first flow channel 201 for screening and separation. In this embodiment, the first film 40 includes any one of a photo-deformable film and an electro-deformable film, and the first film 40 includes a plurality of first sub-holes 401, so that the first film 40 can be controlled to expand and contract by light or electricity, and the size of the first sub-holes 401 can be controlled, and then cell particles with different sizes can be screened and separated. That is, after the solution to be processed by the microfluidic device 000 flows into the first flow channel 201 through the liquid inlet 10A, since the first sub-well 401 and the first through-hole 2011 are at least partially overlapped in the direction Z perpendicular to the plane of the second substrate 20 (optionally, the aperture of the first through-hole 2011 is greater than or equal to the largest aperture of the variable apertures of the first sub-well 401, so that the first through-hole 2011 can be prevented from limiting the screening of the particles), the solution can enter the first sub-well 401 of the first thin film 40 from the plurality of first through-holes 2011 formed in the first flow channel 201 for screening, the particles larger than the first sub-well 401 in the solution to be processed can remain in the first flow channel 201, and the rest of the solution including the particles smaller than or equal to the first sub-well 401 can continuously flow out of the screening through the plurality of first sub-wells 401 (if a substrate or a thin film having sub-wells smaller than the aperture of the first sub-well 401 is continuously disposed under the second substrate 20), or after the recovery, the aperture size of the first sub-hole 401 of the first film 40 is changed by light control or electric control, and then the cell particles enter the liquid inlet 10A again for continuous screening, so that the separation and screening of the cell particles with different sizes are realized.

In this embodiment, a first collecting pool 202 is further disposed on a side of the second substrate 20 facing the first substrate 10, the first collecting pool 202 is formed by a surface of the second substrate 20 close to the first substrate 10 and recessed towards a side far from the first substrate 10, since the first feeding hole 101 is communicated with a first inlet end 201A of the first flow channel 201 (the communication relationship is indicated by a dotted line in fig. 20), the first collecting pool 202 is communicated with a first outlet end 201B of the first flow channel 201, wherein the first inlet end 201A and the first outlet end 201B are opposite ends of the first flow channel 201 in a flowing direction (e.g. a first direction X in the figure), a first assisting agent can be introduced into the first flow channel 201 of the second substrate 20 through the first feeding hole 101, the first assisting agent can be a specific solution or gas, and the specific solution or gas can assist to push particles having a particle diameter larger than a pore diameter of the first sub-hole 401 and remaining in the first flow channel 201, so that it can flow from the first inlet end 201A to the first outlet end 201B of the first flow channel 201 along the flow direction (first direction X) of the first flow channel 201, and enter the first collection tank 202 for collection and extraction.

Alternatively, please refer to fig. 23-25 in combination, fig. 23 is a schematic diagram of another split structure of a microfluidic device according to an embodiment of the present invention, fig. 24 is a top perspective view of the stacked substrates in fig. 23, fig. 25 is a schematic diagram of a cross-sectional structure along the direction D-D' in fig. 24 (it is understood that, in order to clearly illustrate the structures of the substrates in this embodiment, the structures in the drawings are all illustrated in a transparent manner), and a microfluidic device 000 according to this embodiment includes at least a first substrate 10 and a second substrate 20 that are disposed opposite to each other;

at least part of the first flow channel 201 has a depth equal to the thickness of the second substrate 20, or the depth of the first flow channel 201 is equal to the thickness of the second substrate 20, a first thin film 40 is disposed on a side of the second substrate 20 away from the first substrate 10, the first thin film 40 includes any one of a photo-deformable thin film and an electro-deformable thin film, and the first thin film 40 includes a plurality of first sub-holes 401;

the orthographic projection of the plurality of first sub-holes 401 to the second substrate 20 is positioned in the first flow channel 201;

In this embodiment, the first channel 201 is formed on the side of the second substrate 20 facing the first substrate 10, the first channel 201 is formed by the surface of the second substrate 20 close to the first substrate 10 and recessed towards the side far from the first substrate 10, and the depth of the first channel 201 is equal to the thickness of the second substrate 20 (as shown in fig. 25, the first channel 201 is completely hollowed through the thickness of the second substrate 20), and since the liquid inlet 10A is communicated with the first channel 201 (the communication relationship is indicated by a dotted line in fig. 23), the solution to be processed by the microfluidic device 000 entering from the liquid inlet 10A can smoothly enter the first channel 201 of the second substrate 20, and enter the first sub-hole 401 of the first thin film 40 through the first channel 201 which is completely hollowed through the thickness of the second substrate 20 for screening and separation. In this embodiment, the first film 40 includes any one of a photo-deformable film and an electro-deformable film, and the first film 40 includes a plurality of first sub-holes 401, so that the first film 40 can be controlled to expand and contract by light or electricity, and the size of the first sub-holes 401 can be controlled, and then cell particles with different sizes can be screened and separated. That is, after the solution to be processed by the microfluidic device 000 flows into the first flow channel 201 through the liquid inlet 10A, since the orthographic projection of the plurality of first sub-holes 401 to the second substrate 20 is located in the first flow channel 201, the solution can directly enter the first sub-holes 401 of the first thin film 40 from the first flow channel 201 for screening, particles larger than the first sub-holes 401 in the solution to be processed will remain in the first flow channel 201, and the rest of the solution including particles smaller than or equal to the first sub-holes 401 will continue to flow out of the first flow channel through the plurality of first sub-holes 401 for screening (if a substrate or a thin film with sub-holes smaller than the aperture of the first sub-holes 401 is continuously disposed below the second substrate 20), or after the solution is recovered, the size of the first sub-holes 401 of the first thin film 40 is changed by light control or electric control, the solution enters the continuous screening from the liquid inlet 10A again, thereby realizing separation and screening of cellular particles with different sizes.

In this embodiment, a first collecting pool 202 is further disposed on a side of the second substrate 20 facing the first substrate 10, the first collecting pool 202 is formed by a surface of the second substrate 20 close to the first substrate 10 and recessed towards a side far from the first substrate 10, since the first feeding hole 101 is communicated with a first inlet end 201A of the first flow channel 201 (the communication relationship is indicated by a dotted line in fig. 23), the first collecting pool 202 is communicated with a first outlet end 201B of the first flow channel 201, wherein the first inlet end 201A and the first outlet end 201B are opposite ends of the first flow channel 201 in a flowing direction (e.g. a first direction X in the figure), a first assisting agent can be introduced into the first flow channel 201 of the second substrate 20 through the first feeding hole 101, the first assisting agent can be a specific solution or gas, and the specific solution or gas can assist to push particles having a particle diameter larger than a pore diameter of the first sub-hole 401 and remaining in the first flow channel 201, so that it can flow from the first inlet end 201A to the first outlet end 201B of the first flow channel 201 along the flow direction (first direction X) of the first flow channel 201, and enter the first collection tank 202 for collection and extraction.

Alternatively, the depth of the first collection chamber 202 may be smaller than the thickness of the second substrate 20 (as shown in fig. 20), so that the cell particles collected in the first collection chamber 202 can be stored in the first collection chamber 202, which facilitates the next operation. Alternatively, the depth of the first collecting chamber 202 may be equal to the thickness of the second substrate 20, and the first collecting chamber 202 may be directly connected to an external first collecting bottle or other storage device (not shown), so as to facilitate collection and extraction of the cell particles screened and separated through the first sub-hole 401. The subsequent disposal manner of the cellular particles collected in the first collection pool 202 is not particularly limited in this embodiment, and the subsequent disposal manner may be selected according to actual requirements.

The micro-fluidic device 000 of this embodiment can change the size of the aperture of the first sub-hole 401 on the first thin film 40 through electric control or optical control, and then realize the screening and separation of the cell particles of different sizes, and can also realize the extraction and collection of the cell particles of different sizes after the screening and separation through the first collection pool 202 on the second substrate 20, not only can realize the separation and extraction of the cell particles through a simple structure, but also can be beneficial to reducing the whole thickness of the micro-fluidic device, realize the effect of extracting the cell particles of different sizes through the screening of the thinned micro-fluidic device, and is beneficial to improving the efficiency and reducing the cost. Since the microfluidic device 000 of the present embodiment includes at least the first substrate 10 and the second substrate 20 bonded and sealed to each other, the solutions to be processed are all processed in the flow channel of the substrates, and finally collected and extracted through the collection pool, so that the risk of contamination can be reduced.

It should be noted that, in this embodiment, the structure of the microfluidic device 000 is illustrated by only two stacked substrates, and does not show the actual number of the substrates in the microfluidic device 000, in a specific implementation, the number of the substrates in the microfluidic device 000 may be N (N is a positive integer greater than or equal to 3), at this time, the first substrate 10 as the uppermost layer may be provided with N inlets penetrating through the thickness of the first substrate 10, one of the inlets may be a liquid inlet for a solution to be processed, and the remaining inlets may be used as liquid inlet for a booster agent and are respectively communicated with different substrates below the first substrate 10, so as to implement screening, separation, extraction and collection of cell particles with different sizes.

It should be further noted that, in the present embodiment, the shape of the first through-hole 2011 and the first sub-hole 401 are only illustrated as circles, which do not indicate the actual shape thereof, and the arrangement may be selected according to the shape of the cell particles to be screened and extracted.

In some alternative embodiments, referring to fig. 26 in combination, fig. 26 is a schematic cross-sectional view along the direction D-D' in fig. 24, in which when the depth of the first flow channel 201 is equal to the thickness of the second substrate 20, the first film 40 is attached to the second substrate 20 through the first adhesive layer 400. Optionally, the orthographic projection of the first glue layer 400 to the second substrate 20 does not overlap with the first flow channel 201.

This embodiment explains that when the depth of the first runner 201 is equal to the thickness of the second substrate 20, that is, the first runner 201 is completely hollowed out through the thickness of the second substrate 20, the first thin film 40 located on the side of the second substrate 20 away from the first substrate 10 can be attached and fixed to the second substrate 20 through the first adhesive layer 400, and the first runner 201 is a structure that is completely hollowed out through the thickness of the second substrate 20, so that the first sub-holes 401 on the first thin film 40 do not need to consider the problem of hole alignment, and therefore, the first thin film 40 provided with the first sub-holes 401 only needs to be integrally attached to the surface of the second substrate 20 away from the first substrate 10, so that the orthographic projections of the plurality of first sub-holes 401 on the second substrate 20 are located within the range of the first runner 201, thereby facilitating the improvement of the process efficiency and the reduction of the process difficulty. This embodiment still sets up first glue film 400 and does not overlap with first flow channel 201 to the orthographic projection of second base plate 20, when can guaranteeing the laminating effect, can also avoid first glue film 400 to influence the flow of solution in first flow channel 201 and first sub-hole 401, and then is favorable to improving screening efficiency.

It can be understood that, in this embodiment, the fixing manner of the first film 40 and the second substrate 20 is merely illustrated, but not limited to this, in the specific implementation, the first film 40 may also be fabricated on one side of the second substrate 20 away from the first substrate 10 by a vapor deposition process, or when the depth of the first flow channel 201 is smaller than the thickness of the second substrate 20 and the first flow channel 201 is provided with the plurality of first through holes 2011, the fabrication of the first film 40 may also be completed by a process of glue layer bonding or deposition, only the overlapping alignment between the first through holes 2011 and the first sub-holes 401 needs to be ensured.

In some alternative embodiments, please refer to fig. 20-26 and fig. 27 in combination, fig. 27 is a schematic diagram of a frame of another driving method of a microfluidic device according to an embodiment of the present invention, the driving method is used for driving the above microfluidic device to operate, and the driving method includes: a screening stage T1, in which the solution to be treated flows into the first flow channel 201 of the second substrate 20 from the liquid inlet 10A, the aperture size of the first sub-hole 401 of the first film 40 is controlled by illumination or electrification, so that the first particles with the particle size larger than that of the first sub-hole 401 in the solution to be treated are left in the first flow channel 201, and the rest solution flows out from the first sub-hole 401; it is understood that when the first particles and the second particles have a regular shape such as a spherical shape, the particle diameters of the first particles and the second particles are spherical diameters, and when the first particles and the second particles have an ellipsoidal shape, the particle diameters of the first particles and the second particles are the maximum length in the major axis direction; when the first and second particles are irregularly shaped, the particle size of the first and second particles is the length of the line between the two farthest points on the surface of the particles.

In the extraction stage T2, the first assisting agent enters the first flow channel 201 of the second substrate 20 through the first feeding hole 101, and pushes the first particles in the first flow channel 201 to enter the first collecting pool 202, so as to collect and extract the first particles.

Specifically, the driving method for driving the operation of the microfluidic device 000 of the present embodiment may include a screening stage and an extraction stage. In the screening stage T1, the solution to be treated may be flowed from the loading port 10A into the first flow path 201 of the second substrate 20, and flows into the first sub-holes 401 of the first thin film 40 through the first flow channel 201 with a plurality of first through holes 2011 or the first flow channel 201 which is completely hollow and penetrates through the thickness of the second substrate 20 for screening, a plurality of first particles remain in the first flow channel 201, the particle size of the first particles is larger than the pore size of the first sub-pores 401, the remaining solution containing particles smaller than or equal to the first sub-wells 401 will further flow out of the screen through the plurality of first sub-wells 401 (if a substrate or a thin film with sub-wells smaller than the first sub-wells 401 is further disposed under the second substrate 20), or after the recovery, the aperture size of the first sub-hole 401 of the first film 40 is changed by light control or electric control, and then the cell particles enter the liquid inlet 10A again for continuous screening, so that the separation and screening of the cell particles with different sizes are realized. In the extraction stage T2, the first assisting agent enters the first inlet end 201A of the first flow channel 201 of the second substrate 20 through the first inlet 101, and the first assisting agent may be a specific solution or gas, and the specific solution or gas may assist to push the first particles with a larger diameter than the first sub-holes 401 remaining in the first flow channel 201 to move, so that the first particles can flow from the first inlet end 201A to the first outlet end 201B of the first flow channel 201 along the flowing direction (the first direction X) of the first flow channel 201, and enter the first collection pool 202 for collection and extraction. The driving method of the microfluidic device provided by the embodiment can be applied to the microfluidic device in the above embodiment to separate and extract cell particles with different sizes, is beneficial to reducing the overall thickness of the microfluidic device, realizes the effect of screening and extracting the cell particles with different sizes through the thinned microfluidic device, is also beneficial to improving the efficiency and reducing the cost, and can also reduce the risk of contamination of the cell particles.

In some alternative embodiments, please refer to fig. 28, fig. 28 is a schematic diagram illustrating another split structure of the microfluidic device according to the embodiment of the present invention, in which the liquid inlet 10A on the first substrate 10 is communicated with the first flow channel on the second substrate 20 through a first inlet section 100, and a forward projection of the first inlet section 100 to the first substrate 10 is overlapped with the liquid inlet 10A;

the first inlet section 100 is located on the side of the first base plate 10 facing the second base plate 20 (not illustrated in the drawings, and can be understood with particular reference to the embodiments of fig. 9-11); alternatively, the first inlet section 100 is located on the side of the second substrate 20 facing the first substrate 10 (as shown in fig. 28);

this embodiment illustrates that the loading port 10A provided on the first substrate 10 and the first flow channel 201 on the side of the second substrate 20 facing the first substrate 10 can communicate with each other through a first inlet section 100 overlapping with the loading port 10A; optionally, the first inlet section 100 may be formed on a side surface of the second substrate 20 facing the first substrate 10, and only needs to satisfy that the liquid inlet 10A on the first substrate 10 and the first inlet section 100 on the second substrate 20 are overlapped and communicated after the first substrate 10 and the second substrate 20 are overlapped. After the first substrate 10 and the second substrate 20 are stacked, the solution to be processed flowing in through the liquid inlet 10A first passes through the first inlet section 100 on the second substrate 20 and then flows into the first flow channel 201 on the second substrate 20 for the first step of particle screening and separation.

The first inlet section 100 of this embodiment is provided with the first valve K1, so that whether the first inlet section 100 is conducted or not can be controlled by opening and closing the first valve K1, and further whether the liquid inlet 10A of the first substrate 10 is communicated with the first flow channel 201 of the second substrate 20 or not can be controlled, so as to realize flexible control of cell particle operation.

Optionally, the first outlet end 201B of the first flow channel 201 is communicated with the first collecting tank 202 through a second valve K2, and the first inlet 101 is communicated with the first inlet end 201A of the first flow channel 201 through a third valve K3. Wherein, the second valve K2 can be disposed at the first outlet end 201B of the first flow channel 201, and the third valve K3 can be disposed at the first inlet end 201A of the first flow channel 201;

this embodiment illustrates that the first outlet end 201B and the first inlet end 201A of the first flow channel 201 can be provided with a valve for controlling the conduction. When the solution to be treated completes the screening separation work in the first flow channel 201 and enters the particle extraction stage, the first valve K1 on the first inlet section 100 may be closed, and the second valve K2 and the third valve K3 may be opened, at this time, the first feed port 101 is communicated with the first flow channel 201 and the first collection pool 202, the first assisting agent enters the first inlet end 201A of the first flow channel 201 of the second substrate 20 through the first feed port 101, the first assisting agent may be a specific solution or gas, and the specific solution or gas may assist to push the first particles with the particle size larger than the pore size of the first sub-pore 401 remaining in the first flow channel 201 to move so that the first particles can flow from the first inlet end 201A to the first outlet end 201B of the first flow channel 201 along the flow direction (the first direction X) of the first flow channel 201 and enter the first collection pool 202 for collection and extraction of the first particles. The driving method of the microfluidic device provided by the embodiment can be applied to the microfluidic device in the above embodiment to separate and extract cell particles with different sizes, and can also flexibly control the separation and extraction operation to be performed and stopped through each valve, so that the operation is simple and flexible, and the working efficiency is high.

In some optional embodiments, referring to fig. 29, fig. 29 is a schematic view of another disassembled structure of the microfluidic device according to the embodiment of the present invention, in which the material for manufacturing the first valve K1, the second valve K2, and the third valve K3 of the present embodiment includes any one of a photo-deformable material and an electro-deformable material. When the first valve K1, the second valve K2 and the third valve K3 are made of an electro-deformable material, the first valve K1 is connected with a first electrode lead L1, the second valve K2 is connected with a second electrode lead L2, and the third valve K3 is connected with a third electrode lead L3. The first electrode lead L1 and the first valve K1 are disposed at a side of the first substrate 10 facing the second substrate 20; the second electrode lead L2 and the second valve K2 are disposed at a side of the first substrate 10 facing the second substrate 20; the third electrode lead L3 and the third valve K3 are disposed on a side of the first substrate 10 facing the second substrate 20. It can be understood that, in this embodiment, details of the working principle and the structure of the valve made of the photo-deformable material or the electro-deformable material are not described, and the embodiment may be understood with reference to the above embodiments of fig. 12 to fig. 19.

In some alternative embodiments, referring to fig. 30, fig. 30 is a schematic diagram of another split structure of the microfluidic device according to the embodiment of the present invention (it is understood that, for clarity, structures of the substrates in this embodiment are all illustrated in transparent form), the microfluidic device 000 in this embodiment may further include a third substrate 30, where the third substrate 30 is located on a side of the second substrate 20 away from the first substrate 10;

the first substrate 10 is further provided with at least a second feed port 102, and the second feed port 102 penetrates through the first substrate 10 along the thickness direction of the first substrate 10;

a second flow channel 301 and a second collecting tank 302 are formed on one side of the third substrate 30 facing the second substrate 20, the second feed inlet 102 is communicated with a second inlet end 301A of the second flow channel 301, and the second collecting tank 302 is communicated with a second outlet end 301B of the second flow channel 301; the second inlet end 301A and the second outlet end 301B are opposite ends of the second flow channel 301 in the flow direction;

the depth of the second flow channel 301 is less than or equal to the thickness of the third substrate 30, a second film 50 is arranged on one side of the third substrate 30 away from the second substrate 20, the second film 50 includes any one of a photo-deformable film or an electro-deformable film, and the second film 50 includes a plurality of second sub-holes 501;

when the depth of the second flow channel 301 is smaller than the thickness of the third substrate 30, the second flow channel 301 includes a plurality of second through holes, and in a direction perpendicular to the plane of the third substrate 30, the second sub-holes 501 at least partially overlap with the second through holes (not shown in the drawings, and can be understood with specific reference to the structure of the first flow channel in fig. 20-22);

when the depth of the second flow channel 301 is equal to the thickness of the third substrate 30 (as shown in fig. 30), the orthogonal projection of the plurality of second sub-holes 501 to the third substrate 30 is located in the second flow channel 301;

the second feeding hole 102 is used for flowing a second booster to push the solution in the second flow channel 301 to flow into the second collecting tank 302.

This embodiment further explains that the second channel 301 is opened on the side of the third substrate 30 facing the second substrate 20, the second channel 301 is formed by the surface of the third substrate 30 close to the second substrate 20 and recessing towards the side far from the second substrate 20, and the depth of the second channel 301 can be smaller than or equal to the thickness of the second substrate 20 (as exemplified in fig. 30 by the second channel 301 being completely hollowed through the thickness of the third substrate 30), since the liquid inlet 10A is communicated with the first channel 201 (the communication relationship is illustrated by the dotted line in fig. 30), the solution to be processed by the microfluidic device 000 entering from the liquid inlet 10A can smoothly enter the first channel 201 of the second substrate 20, and enter the first sub-hole 401 of the first thin film 40 through the first channel 201 being completely hollowed through the thickness of the second substrate 20 for the first screening separation, and then the solution screened through the first sub-hole 401 continues to the first channel 301 of the third substrate 30, and the second flow channel 301 which penetrates through the thickness of the third substrate 30 is completely hollowed out to enter the second sub-hole 501 of the second film 50 for further screening and separation.

Optionally, in this embodiment, the first film 40 and the second film 50 include any one of a photo-deformable film or an electro-deformable film, the first film 40 includes a plurality of first sub-holes 401, and the second film 50 includes a plurality of second sub-holes 501, so that expansion and contraction of the first film 40 can be controlled by light or electricity, and then sizes of the first sub-holes 401 and the second sub-holes 501 are controlled, and further cell particles with different sizes are flexibly screened and separated. That is, after the solution to be processed by the microfluidic device 000 flows into the first flow channel 201 through the liquid inlet 10A, since the orthographic projections of the plurality of first sub-holes 401 on the second substrate 20 are located in the first flow channel 201, the solution can directly enter the first sub-holes 401 of the first thin film 40 from the first flow channel 201 to perform the first screening, the particles larger than the first sub-holes 401 in the solution to be processed will remain in the first flow channel 201, the rest of the solution including the particles smaller than or equal to the first sub-holes 401 will continuously flow out through the plurality of first sub-holes 401 to further screen through the second sub-holes 501, the particles larger than the second sub-holes 501 will remain in the second flow channel 301, and the rest of the solution can be recovered, thereby realizing the separation and screening of the cell particles with different sizes. Alternatively, the first membrane 40 and the second membrane 50 may be optically or electrically controlled to make the pore size of the second sub-pore 501 smaller than that of the first sub-pore 401, so as to realize one-step screening separation of cell particles.

In this embodiment, a first collecting pool 202 is further disposed on a side of the second substrate 20 facing the first substrate 10, the first collecting pool 202 is formed by recessing a surface of the second substrate 20 close to the first substrate 10 toward a side far from the first substrate 10, a second collecting pool 302 is disposed on a side of the third substrate 30 facing the second substrate 20, the second collecting pool 302 is formed by recessing a surface of the third substrate 30 close to the second substrate 20 toward a side far from the second substrate 20, since the first inlet port 101 is communicated with a first inlet port 201A of the first flow channel 201 (the communication relationship is indicated by a dotted line in fig. 30), the first collecting pool 202 is communicated with a first outlet port 201B of the first flow channel 201, wherein the first inlet port 201A and the first outlet port 201B are opposite ends of the first flow channel 201 in a flowing direction (such as a first direction X in the figure), the first assisting agent can be introduced into the first flow channel 201 of the second substrate 20 through the first inlet port 101, the first assisting agent may be a specific solution or gas, and the specific solution or gas may assist to push the particles with the size larger than the pore size of the first sub-pores 401 remaining in the first flow channel 201, so that the particles can flow from the first inlet end 201A to the first outlet end 201B of the first flow channel 201 along the flow direction (the first direction X) of the first flow channel 201, and enter the first collecting tank 202 for collection and extraction. Since the second feed port 102 communicates with the second inlet end 301A of the second flow channel 301 (the communication is illustrated by the dotted line in fig. 30), the second collecting tank 302 communicates with the second outlet end 301B of the second flow channel 301, wherein the second inlet end 301A and the second outlet end 301B are opposite ends of the second flow channel 301 in the direction of flow (as shown in the figure as the first direction X), the second assisting agent may be introduced into the second flow channel 301 of the third substrate 30 through the second inlet port 102, the second assisting agent may be a specific solution or gas, the specific solution or gas can assist to push the particles with the diameter larger than the diameter of the second sub-holes 501, which are left in the second flow channel 301, to flow along the flow direction (first direction X) of the second flow channel 301 from the second inlet end 301A to the second outlet end 301B of the second flow channel 301, and enter the second collection pool 302 for collection and extraction.

Optionally, the second outlet end 301B of the second flow channel 301 is connected to the second collecting tank 302 through a fourth valve K4, and the second inlet port 301A is connected to the second inlet end 301A of the second flow channel 301 through a fifth valve K5. This embodiment illustrates that the second outlet end 301B and the second inlet end 301A of the second flow channel 301 may be provided with a valve for controlling the conduction. When the solution to be treated completes the screening separation work in the second flow path 301 to enter the particle extraction stage, the first valve K1 on the first inlet section 100 can be closed, the second valve K2 and the third valve K3 can be closed, the fourth valve K4 and the fifth valve K5 can be opened, the second inlet 102 is connected to the second flow channel 301 and the second collecting tank 302, the second auxiliary agent enters the second inlet 301A of the second flow channel 301 of the third substrate 30 through the second inlet 102, the second auxiliary agent can be a specific solution or gas, the specific solution or gas can assist to push the second particles with a larger diameter than the second sub-holes 501 in the second flow channel 301 to move, so that the second particles can flow along the flow direction (the first direction X) of the second flow channel 301 from the second inlet end 301A to the second outlet end 301B of the second flow channel 301, and enter the second collection pool 302 for collection and extraction of the second particles. The driving method of the microfluidic device provided by the embodiment can be applied to the microfluidic device in the above embodiment to separate and extract cell particles with different sizes, and can also flexibly control the separation and extraction operation to be performed and stopped through each valve, so that the operation is simple and flexible, and the working efficiency is high.

In some optional embodiments, referring to fig. 31, fig. 31 is a schematic diagram of another split structure of the microfluidic device according to the embodiment of the present invention, in this embodiment, the fourth valve K4 and the fifth valve K5 may be made of the same material as that of the first valve K1, the second valve K2, and the third valve K3, and both include any one of a photo-deformable material and an electro-deformable material. Optionally, when the fourth valve K4 and the fifth valve K5 are made of an electro-deformable material, such as an electro-expandable colloidal crystal film (a reactant of monodisperse polystyrene microspheres and ferrocene derivatives, etc.), the fourth valve K4 is connected to a fourth electrode lead L4, and the fifth valve K5 is connected to a fifth electrode lead L5; the fourth electrode lead L4 and the fourth valve K4 are disposed at a side of the second substrate 20 facing the third substrate 30; the fifth electrode lead L5 and the fifth valve K5 are disposed at a side of the second substrate 20 facing the third substrate 30. It can be understood that, in this embodiment, details of the working principle and the structure of the valve made of the photo-deformable material or the electro-deformable material are not described, and the embodiment may be understood with reference to the above embodiments of fig. 12 to fig. 19.

In some alternative embodiments, referring to fig. 32, fig. 32 is a schematic diagram illustrating another split structure of a microfluidic device according to an embodiment of the present invention, in this embodiment, when the first film 40 and the second film 50 are electrostrictive films, the first film 40 is connected to a sixth electrode lead L6, and the second film 50 is connected to a seventh electrode lead L7; alternatively, the sixth electrode lead L6 may include two, that is, the sixth electrode lead L61 and the sixth electrode lead L62 are connected to both ends of the first film 40, respectively, and the seventh electrode lead L7 may include two, that is, the seventh electrode lead L71 and the seventh electrode lead L72 are connected to both ends of the second film 50, respectively;

the sixth electrode lead L6 is disposed on the second substrate 20 at a side away from the first substrate 10, and the seventh electrode lead L7 is disposed on the third substrate 30 at a side away from the second substrate 20.

This embodiment explains that when the first film 40 and the second film 50 are electro-deformable films, the first film 40 is connected with the sixth electrode lead L6, and the second film 50 is connected with the seventh electrode lead L7; the sixth electrode leads L61 and L62 are used for respectively receiving different external control signals to the two ends of the first film 40, so that the external control signals are transmitted to the two ends of the first film 40 of the electro-deformable film through the sixth electrode leads L61 and L62, expansion or contraction of the first film 40 is controlled through driving electric signals, and the aperture size of the first sub-hole 401 is controlled. For example, when the first sub-hole 401 needs to be larger, the first film 40 of the electro-deformable material can be expanded through electrical treatment (such as energization or not), so as to drive the first sub-hole 401 to expand and expand to a desired large aperture, and when the first film 40 is not energized, the first sub-hole 401 is reduced by contracting the first film 40, and in specific implementation, the first film 40 can be set to expand or contract when the first film is energized according to the property of the specific electro-deformable material. The seventh electrode leads L71 and L72 are used for respectively receiving different external control signals to the two ends of the second film 50, so that the external control signals are transmitted to the two ends of the second film 50 of the electro-deformable film through the seventh electrode leads L71 and L72, thereby controlling the expansion or contraction of the second film 50 through the driving electrical signals, and further controlling the aperture size of the second sub-hole 501. For example, when the second sub-hole 501 needs to be larger, the second film 50 of the electro-deformable material can be expanded through electrical treatment (such as powering on or not), so as to drive the second sub-hole 501 to expand and expand to a desired large aperture, and when the second film 50 is not powered on, the second film 50 contracts so as to reduce the second sub-hole 501.

Alternatively, the sixth electrode lead L6 may be fabricated on the first film 40 on the side of the second substrate 20 away from the first substrate 10, and the seventh electrode lead L7 may be fabricated on the second film 50 on the side of the third substrate 30 away from the second substrate 20. Since the first flow channel 201, the first inlet section 100, and the first collecting tank 202 are mainly formed on the surface of the second substrate 20 facing the first substrate 10 by an etching process, the second flow channel 301, the second inlet section 200, and the second collecting tank 302 are mainly formed on the surface of the third substrate 30 facing the second substrate 20 by an etching process, and the electrode lead is mainly made of a conductive material by an attaching or depositing process, if the electrode lead is still made on the surface of the second substrate 20 facing the first substrate 10 and the surface of the third substrate 30 facing the second substrate 20, the performance of the deposited or attached valve and electrode lead may be affected due to the uneven surfaces after etching, and the manufacturing yield may be reduced.

Therefore, in the present embodiment, the sixth electrode lead L6 made of a conductive material by an attaching or depositing process is formed on the first film 40 on the side of the second substrate 20 away from the first substrate 10, the seventh electrode lead L7 is formed on the second film 50 on the side of the third substrate 30 away from the second substrate 20, the surface of the second substrate 20 facing the first substrate 10 is specially formed with the first flow channel 201, the first inlet section 100, and the first collecting tank 202 by an etching process, and the surface of the third substrate 30 facing the second substrate 20 is specially formed with the second flow channel 301, the second inlet section 200, and the second collecting tank 302 by an etching process, so that the influence of the uneven surface on the performance of the valve and the electrode lead can be avoided, and the manufacturing yield can be improved.

As can be seen from the above embodiments, the microfluidic device and the driving method thereof according to the present invention at least achieve the following advantages:

Although some specific embodiments of the present invention have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustrative purposes only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. The microfluidic device is characterized by at least comprising a first substrate, a second substrate and a third substrate which are arranged in a stacked mode;

the first substrate is at least provided with a liquid inlet, a first feed inlet and a second feed inlet, and the liquid inlet, the first feed inlet and the second feed inlet penetrate through the first substrate along the thickness direction of the first substrate;

a first flow channel and a first collecting pool are formed in one side, facing the first substrate, of the second substrate, and the depth of the first flow channel is smaller than the thickness of the second substrate; the liquid inlet is communicated with the first flow channel, the first feed inlet is communicated with a first inlet end of the first flow channel, and the first collecting tank is communicated with a first outlet end of the first flow channel; wherein the first inlet end and the first outlet end are opposite ends of the first flow channel in the flow direction;

a second flow channel and a second collecting pool are formed in one side, facing the second substrate, of the third substrate, and the depth of the second flow channel is smaller than the thickness of the third substrate; the first flow channel is communicated with the second flow channel, the second feed inlet is communicated with a second inlet end of the second flow channel, and the second collecting tank is communicated with a second outlet end of the second flow channel; wherein the second inlet end and the second outlet end are opposite ends of the second flow channel in the flow direction;

the first flow channel comprises a plurality of first through holes, the second flow channel comprises a plurality of second through holes, and the aperture of each first through hole is larger than that of each second through hole in the direction perpendicular to the plane of the first substrate;

the liquid inlet is used for flowing in a solution to be treated, the first feeding hole is used for flowing in a first boosting agent to push the solution in the first flow channel to flow into the first collecting pool, and the second feeding hole is used for flowing in a second boosting agent to push the solution in the second flow channel to flow into the second collecting pool.

2. The microfluidic device according to claim 1, wherein the liquid inlet communicates with the first flow channel through a first inlet section, an orthographic projection of the first inlet section to the first substrate overlapping the liquid inlet;

the first inlet section is positioned on one side of the first base plate facing the second base plate; or, the first inlet section is positioned on one side of the second substrate facing the first substrate;

the first inlet section is provided with a first valve.

3. The microfluidic device according to claim 2, wherein the second flow channel communicates with the first flow channel through a second inlet section, an orthographic projection of the second inlet section to the second substrate overlapping the first flow channel;

the second inlet section is located on a side of the third base plate facing the second base plate.

4. The microfluidic device according to claim 3,

the first outlet end of the first flow channel is communicated with the first collecting tank through a second valve, and the first feeding hole is communicated with the first inlet end of the first flow channel through a third valve;

the second outlet end of the second flow channel is communicated with the second collecting tank through a fourth valve, and the second feeding hole is communicated with the second inlet end of the second flow channel through a fifth valve.

5. The microfluidic device according to claim 4, wherein the first, second, third, fourth, and fifth valves are made of a material including any one of a photo-deformable material or an electro-deformable material.

6. The microfluidic device according to claim 5, wherein when the first valve is made of an electro-deformable material, the first valve is connected with a first electrode lead.

7. The microfluidic device according to claim 5, wherein when the first, second, third, fourth, and fifth valves are made of an electro-deformable material, the first valve is connected to a first electrode lead, the second valve is connected to a second electrode lead, the third valve is connected to a third electrode lead, the fourth valve is connected to a fourth electrode lead, and the fifth valve is connected to a fifth electrode lead.

8. The microfluidic device according to claim 7, wherein the first electrode lead and the first valve are disposed on a side of the first substrate facing the second substrate;

the second electrode lead and the second valve are disposed on a side of the first substrate facing the second substrate; the third electrode lead and the third valve are arranged on one side of the first substrate facing the second substrate;

the fourth electrode lead and the fourth valve are arranged on one side, facing the third substrate, of the second substrate; the fifth electrode lead and the fifth valve are disposed on one side of the second substrate facing the third substrate.

9. A microfluidic device comprising at least a first substrate and a second substrate arranged opposite to each other;

the first substrate is at least provided with a liquid inlet and a first feed inlet, and the liquid inlet and the first feed inlet penetrate through the first substrate along the thickness direction of the first substrate;

a first flow channel and a first collecting pool are formed in one side, facing the first substrate, of the second substrate, and the liquid inlet is communicated with the first flow channel; the first feed inlet is communicated with a first inlet end of the first flow channel, and the first collecting tank is communicated with a first outlet end of the first flow channel; wherein the first inlet end and the first outlet end are opposite ends of the first flow channel in the flow direction;

the depth of the first flow channel is smaller than or equal to the thickness of the second substrate, a first thin film is arranged on one side, far away from the first substrate, of the second substrate, the first thin film comprises any one of a photoinduced deformation thin film or an electrostrictive deformation thin film, and the first thin film comprises a plurality of first sub-holes;

when the depth of the first flow channel is smaller than the thickness of the second substrate, the first flow channel comprises a plurality of first through holes, and the first sub-holes are at least partially overlapped with the first through holes in the direction perpendicular to the plane of the second substrate;

when the depth of the first flow channel is equal to the thickness of the second substrate, the orthographic projection of the first sub-holes to the second substrate is positioned in the first flow channel;

the liquid inlet is used for flowing in a solution to be treated, and the first feeding hole is used for flowing in a first boosting agent to push the solution in the first flow channel to flow into the first collecting tank.

10. The microfluidic device according to claim 9, wherein when the depth of the first channel is equal to the thickness of the second substrate, the first film is attached to the second substrate through a first adhesive layer.

11. The microfluidic device according to claim 9, wherein the loading port communicates with the first flow channel through a first inlet section, an orthographic projection of the first inlet section to the first substrate overlapping the loading port;

the first inlet section is provided with a first valve.

12. The microfluidic device according to claim 11,

the first outlet end of the first flow channel is communicated with the first collecting tank through a second valve, and the first feeding hole is communicated with the first inlet end of the first flow channel through a third valve.

13. The microfluidic device according to claim 12, wherein the first valve, the second valve, and the third valve are made of a material including any one of a photo-deformable material and an electro-deformable material.

14. The microfluidic device according to claim 13, wherein when the first valve is made of an electro-deformable material, the first valve is connected with a first electrode lead.

15. The microfluidic device according to claim 13, wherein when the first, second, and third valves are made of an electro-deformable material, the first valve is connected to a first electrode lead, the second valve is connected to a second electrode lead, and the third valve is connected to a third electrode lead.

16. The microfluidic device according to claim 15,

the first electrode lead and the first valve are arranged on one side, facing the second substrate, of the first substrate;

the second electrode lead and the second valve are disposed on a side of the first substrate facing the second substrate; the third electrode lead and the third valve are disposed on a side of the first substrate facing the second substrate.

17. The microfluidic device according to claim 10, further comprising a third substrate on a side of the second substrate remote from the first substrate;

the first substrate is at least provided with a second feeding hole, and the second feeding hole penetrates through the first substrate along the thickness direction of the first substrate;

a second flow channel and a second collecting tank are formed in one side, facing the second substrate, of the third substrate, the second feed inlet is communicated with a second inlet end of the second flow channel, and the second collecting tank is communicated with a second outlet end of the second flow channel; wherein the second inlet end and the second outlet end are opposite ends of the second flow channel in the flow direction;

the depth of the second flow channel is less than or equal to the thickness of the third substrate, a second thin film is arranged on one side, far away from the second substrate, of the third substrate, the second thin film comprises any one of a photoinduced deformation thin film or an electrostrictive deformation thin film, and the second thin film comprises a plurality of second sub-holes;

when the depth of the second flow channel is smaller than the thickness of the third substrate, the second flow channel comprises a plurality of second through holes, and the second sub-holes are at least partially overlapped with the second through holes in the direction perpendicular to the plane of the third substrate;

when the depth of the second flow channel is equal to the thickness of the third substrate, the orthographic projection of the second sub-holes to the third substrate is positioned in the second flow channel;

and the second feeding hole is used for flowing a second booster to push the solution in the second flow channel to flow into the second collecting tank.

18. The microfluidic device according to claim 17, wherein the second sub-well has a smaller pore size than the first sub-well.

19. The microfluidic device according to claim 17,

20. The microfluidic device according to claim 19, wherein the fourth valve and the fifth valve are made of any one of a photo-deformable material and an electro-deformable material.

21. The microfluidic device according to claim 20, wherein when the fourth valve and the fifth valve are made of an electro-deformable material, the fourth valve is connected with a fourth electrode lead, and the fifth valve is connected with a fifth electrode lead;

22. The microfluidic device according to claim 17, wherein when the first and second films are electrostrictive films, the first film is connected to a sixth electrode lead and the second film is connected to a seventh electrode lead;

the sixth electrode lead is arranged on one side, far away from the first substrate, of the second substrate, and the seventh electrode lead is arranged on one side, far away from the second substrate, of the third substrate.

23. A driving method of a microfluidic device, wherein the driving method is used for driving the microfluidic device according to claim 1 to operate, and the driving method comprises:

in the screening stage, the solution to be treated flows into the first flow channel of the first substrate from the liquid inlet, enters the second flow channel of the second substrate after being screened by the first through hole of the first flow channel, and is screened again by the second through hole of the second flow channel; at this time, a plurality of first particles are remained in the first flow channel, and the particle size of the first particles is larger than the aperture of the first through hole; a plurality of second particles are remained in the second flow channel, and the particle size of the second particles is larger than the aperture of the second through hole;

in the extraction stage, a first boosting agent enters the first flow channel of the first substrate through the first feed inlet, pushes the first particles in the first flow channel to enter the first collection pool, and collects and extracts the first particles; and a second assisting agent enters the second flow channel of the second substrate through the second feed inlet, pushes the second particles in the second flow channel to enter the second collection pool, and collects and extracts the second particles.

24. A method for driving a microfluidic device, the method being used for driving the microfluidic device according to claim 9, the method comprising:

in the screening stage, a solution to be treated flows into the first flow channel of the first substrate from the liquid inlet, the aperture size of the first sub-hole of the first film is controlled through illumination or electrification, so that first particles with the particle size larger than that of the first sub-hole in the solution to be treated are remained in the first flow channel, and the rest solution flows out of the first sub-hole;

and in the extraction stage, a first boosting agent enters the first flow channel of the first substrate through the first feed inlet, and pushes the first particles in the first flow channel to enter the first collection pool, so as to collect and extract the first particles.