CN112755933B

CN112755933B - Multistage reaction micro-channel structure, micro-fluidic chip and heterogeneous reaction method

Info

Publication number: CN112755933B
Application number: CN202110043940.9A
Authority: CN
Inventors: 王超; 蒋志强; 李嘉辉
Original assignee: Guangdong University of Technology
Current assignee: Guangdong University of Technology
Priority date: 2021-01-13
Filing date: 2021-01-13
Publication date: 2023-12-26
Anticipated expiration: 2041-01-13
Also published as: CN112755933A

Abstract

The application provides a multistage reaction micro-channel structure, a micro-fluidic chip and a heterogeneous reaction method, wherein the multistage reaction micro-channel structure comprises: the device comprises a continuous outer triangle expansion focusing unit, an active valve quantitative uniform control unit and a multi-stage heterogeneous reaction tank unit; the continuous outer triangle expansion focusing unit comprises: a continuous outer triangular expanded focusing flow channel and a continuous liquid phase flow channel; the active valve quantitative uniform control unit comprises a first active valve, a second active valve and a third active valve, wherein the first active valve comprises a built-in valve plug, a gas phase channel and a gas buffer chamber; the inner wall of the continuous liquid phase runner is provided with a built-in valve plug; the multi-stage heterogeneous reaction tank unit comprises a first-stage heterogeneous reaction tank unit and a second-stage heterogeneous reaction tank unit. The method solves the technical problems of how to design a microfluidic device and an operation process, so that the microfluidic device can realize rapid and accurate quantitative control to perform accurate and efficient heterogeneous reaction on the basis of generating high-dispersion liquid drops and particles, and the sufficiency of the reaction is improved.

Description

Multistage reaction micro-channel structure, micro-fluidic chip and heterogeneous reaction method

Technical Field

The application relates to the technical field of microfluidics, in particular to a multistage reaction micro-channel structure, a microfluidic chip and a heterogeneous reaction method.

Background

With the development of technology, more and more fields (energy, immunity, biochemistry and the like) need to use miniaturized reaction means to perform highly dispersed micro-precise operation, and the micro-fluidic technology receives a great deal of attention because of being capable of realizing a plurality of micro-processes and micro-operations which are difficult to finish. Microfluidic is the manipulation of tiny particles (or samples) that cannot be achieved by some conventional methods using microchannels and devices. The method can integrate biological detection, a series of biochemical reactions and preparation of various samples on a tiny chip for special operation, and has wide application prospect in multiple fields.

At present, in the conventional preparation process of liquid drops or microsphere particles, a mechanical stirring method under a large scale is mainly adopted, so that microsphere particles with specific particle size cannot be accurately screened, the dispersibility of the particles is low, and the high-efficiency performance of the reaction cannot be ensured because the number of liquid drops (or particles) participating in the reaction is too large or too small. The micro-fluidic system with a special structure can be used for uniformly dispersing liquid drops (or particles), and then carrying out effective and sufficient reaction after quantitative control, so that the efficiency and the experiment success rate can be effectively improved.

There are many methods of generating (or coating droplets of particles) using microfluidics, active application of magnetic field and electric field is required; the passive type is generally a dean flow, no energy input is needed, and the device is simple, convenient and easy to maintain and has small volume. Passive dien flow is one of the most effective ways to focus droplets (or droplets encapsulating particles) by micro-flow control at present due to its simple and convenient operation and uniformity and high efficiency. By passive dien flow focusing, the scattered microspheres and droplets can be focused in the micro-channel to form microspheres and droplet queues which are distributed at specific positions at equal intervals. Although the dispersion of the droplets (or particles) is achieved to some extent, a certain length of spiral-shaped flow path is required to achieve the purpose, and precise quantitative control is difficult.

Therefore, how to design a microfluidic device and an operation process, so that on the basis of generating highly dispersed liquid drops and particles, rapid and accurate quantitative control is realized to perform accurate and efficient heterogeneous reaction, and the sufficiency of the reaction is improved, so that the microfluidic device and the operation process become one of the problems to be solved in the technical urgent need in the art.

Disclosure of Invention

The utility model provides a multistage reaction micro-channel structure, micro-fluidic chip and heterogeneous reaction method for how to design a micro-fluidic device and operation technology, make it can realize quick accurate quantitative control and carry out accurate high-efficient heterogeneous reaction on the basis of producing high dispersion liquid drop, granule, and improve the technical problem of the sufficiency of reaction.

To solve the above problems, the present application provides a multistage reaction microchannel structure, comprising: the device comprises a continuous outer triangle expansion focusing unit, an active valve quantitative uniform control unit and a multi-stage heterogeneous reaction tank unit;

the continuous outer triangle expansion focusing unit includes: a continuous liquid phase sample inlet, a continuous outer triangle expansion focusing runner, a continuous liquid phase runner, an air inlet and an air inlet runner;

the continuous liquid phase sample inlet is communicated with the liquid inlet end of the continuous outer triangular expansion focusing flow passage, the liquid inlet end of the continuous liquid phase flow passage is communicated with the liquid outlet end of the continuous outer triangular expansion focusing flow passage, the air outlet end of the air inlet flow passage is communicated with the continuous liquid phase flow passage, and the air inlet end of the air inlet flow passage is communicated with the air inlet;

the multistage heterogeneous reaction tank unit comprises a first stage heterogeneous reaction tank unit and a second stage heterogeneous reaction tank unit;

the primary heterogeneous reaction tank unit comprises: the device comprises a first reaction liquid phase sample inlet, a first reaction liquid phase flow channel, a first heterogeneous reaction tank and a first liquid outlet flow channel;

the liquid inlet end of the first reaction liquid-phase runner is communicated with the first reaction liquid-phase sample inlet, the liquid outlet end of the first reaction liquid-phase runner is communicated with the liquid inlet end of the first heterogeneous reaction tank, the liquid outlet end of the continuous liquid-phase runner is communicated with the liquid inlet end of the first heterogeneous reaction tank, and the liquid outlet end of the heterogeneous reaction tank is communicated with the liquid inlet end of the first liquid outlet runner;

The secondary heterogeneous reaction tank unit comprises: the second reaction liquid phase sample inlet, the second reaction liquid phase flow channel, the second heterogeneous reaction tank, the second liquid outlet flow channel and the mixed phase sample outlet;

the liquid inlet end of the second reaction liquid-phase flow channel is communicated with the second reaction liquid-phase sample inlet, the liquid outlet end of the second reaction liquid-phase flow channel is communicated with the liquid inlet end of the second heterogeneous reaction tank, the liquid outlet end of the first liquid-phase flow channel is communicated with the liquid inlet end of the second heterogeneous reaction tank, the liquid outlet end of the heterogeneous reaction tank is communicated with the second liquid outlet flow channel, and the liquid outlet end of the second liquid outlet flow channel is communicated with the mixed phase sample outlet;

the active valve quantitative and uniform control unit comprises: the first active valve is arranged in the continuous liquid phase flow channel, the second active valve is arranged in the first liquid outlet flow channel, and the third active valve is arranged in the second liquid outlet flow channel;

the first active valve includes: a valve plug, a gas phase sample inlet, a gas phase channel and a gas buffer chamber are arranged in the valve plug;

the built-in valve plug is arranged in the continuous liquid phase flow channel, the gas outlet end of the gas phase channel is communicated with the gas buffer chamber, the gas inlet end of the gas phase channel is communicated with the gas phase sample inlet, and the gas buffer chamber corresponds to the built-in valve plug;

The second active valve and the third active valve are both identical in structure to the first active valve.

Further, the continuous outer triangle expansion focusing flow passage is spiral;

the liquid inlet end of the continuous outer triangle expansion focusing flow passage is positioned at the center of the spiral shape;

the liquid outlet end of the continuous outer triangle expansion focusing flow passage is positioned at the outer side of the spiral shape.

Further, the number of the first active valves is at least one, and the number of the second active valves is at least one.

Further, the built-in valve plug comprises a trapezoid valve block and a rectangular valve block;

the trapezoid valve block is arranged on one side, far away from the gas buffer chamber, of the inner wall of the continuous liquid phase flow channel, and the bottom surface of the trapezoid valve block is attached to the inner wall of the continuous liquid phase flow channel;

the rectangular valve blocks are arranged on one side, close to the gas buffer chamber, of the inner wall of the continuous liquid phase flow channel, the rectangular valve blocks and the trapezoid valve blocks are distributed in a staggered mode, and the side walls, corresponding to the trapezoid valve blocks, of the rectangular valve blocks are located on the same section of the continuous liquid phase flow channel.

Furthermore, the gas buffer chamber and the continuous liquid phase runner are made of deformable materials, the gas buffer chamber is not deformed in a non-inflated state, and the gas buffer chamber expands in an inflated state and is abutted against one side of the continuous liquid phase runner, so that the inner wall of the continuous liquid phase runner is fully contacted with the built-in valve plug, and the continuous liquid phase runner is blocked.

Further, the cross sections of the continuous liquid phase flow channel, the gas phase flow channel and the reaction liquid phase flow channel are rectangular, the heights of the various flow channels are uniform, and the heights are 100-200 mu m.

Further, the side walls of the first heterogeneous reaction tank and the second heterogeneous reaction tank are circular side walls.

The application also provides a microfluidic chip, which comprises a chip body and the multistage reaction micro-channel structure;

the multistage reaction micro-channel structure is arranged in the chip body.

Further, the chip body comprises a base plate and a cover plate;

the multistage reaction micro-channel structure is arranged on the upper surface of the substrate;

the cover plate covers the upper surface of the substrate, and the continuous liquid phase sample inlet, the gas phase sample inlet, the reaction liquid phase sample inlet and the mixed phase sample outlet are all communicated with the cover plate.

Further, the device also comprises a conveying device and an extracting device;

the conveying device comprises a first conveying pump communicated with the continuous liquid phase sample inlet, a second conveying pump communicated with the gas phase sample inlet of the first active valve, a third conveying pump communicated with the first reaction liquid phase sample inlet, a fourth conveying pump communicated with the gas phase sample inlet of the second active valve, a fifth conveying pump communicated with the second reaction liquid phase sample inlet, a sixth conveying pump communicated with the gas phase sample inlet of the third active valve and a seventh conveying pump communicated with the gas inlet;

The extraction device is communicated with the mixed phase sample outlet.

The application also provides a heterogeneous reaction method which is applied to the multistage reaction micro-channel structure and comprises the following steps:

uniformly and stably dispersing microsphere suspension liquid through a continuous outer triangular expansion focusing flow passage, flowing into a continuous liquid phase passage, and guiding the microsphere suspension liquid into a first heterogeneous reaction tank through the continuous liquid phase passage;

the flow of the continuous liquid phase flow channel is regulated by a first active valve of the active valve quantitative and uniform control unit;

a reaction liquid enters a first heterogeneous reaction tank through a first reaction liquid flow channel, is in short contact with a first heterogeneous microsphere suspension, enters the first heterogeneous reaction tank for reaction, and is transmitted to a second heterogeneous reaction tank through a first liquid outlet flow channel;

the flow of the first liquid outlet flow channel is regulated by a second active valve of the active valve quantitative uniform control unit;

the other reaction liquid enters a second heterogeneous reaction tank through a second reaction liquid flow channel and fully reacts with substances in the second heterogeneous reaction tank, and the reacted substances are discharged from a second liquid outlet flow channel;

and the flow of the second liquid outlet flow passage is regulated by a third active valve of the active valve quantitative uniform control unit.

Compared with the prior art, the embodiment of the application has the advantages that:

the application provides a multistage reaction microchannel structure, include: the device comprises a continuous outer triangle expansion focusing unit, an active valve quantitative uniform control unit and a multi-stage heterogeneous reaction tank unit; the continuous outer triangle expansion focusing unit comprises: a continuous liquid phase sample inlet, a continuous outer triangle expansion focusing runner, a continuous liquid phase runner, an air inlet and an air inlet runner; the continuous liquid phase sample inlet is communicated with the liquid inlet end of the continuous outer triangular expansion focusing flow passage, the liquid inlet end of the continuous liquid phase flow passage is communicated with the liquid outlet end of the continuous outer triangular expansion focusing flow passage, the gas outlet end of the gas inlet flow passage is communicated with the continuous liquid phase flow passage, and the gas inlet end of the gas inlet flow passage is communicated with the gas inlet; the multi-stage heterogeneous reaction tank unit comprises a first-stage heterogeneous reaction tank unit and a second-stage heterogeneous reaction tank unit; the primary heterogeneous reaction tank unit comprises: the device comprises a first reaction liquid phase sample inlet, a first reaction liquid phase flow channel, a first heterogeneous reaction tank and a first liquid outlet flow channel; the liquid inlet end of the first reaction liquid phase runner is communicated with the first reaction liquid phase sample inlet, the liquid outlet end of the first reaction liquid phase runner is communicated with the liquid inlet end of the first heterogeneous reaction tank, the liquid outlet end of the continuous liquid phase runner is communicated with the liquid inlet end of the first heterogeneous reaction tank, and the liquid outlet end of the heterogeneous reaction tank is communicated with the liquid inlet end of the first liquid outlet runner; the secondary heterogeneous reaction tank unit comprises: the second reaction liquid phase sample inlet, the second reaction liquid phase flow channel, the second heterogeneous reaction tank, the second liquid outlet flow channel and the mixed phase sample outlet; the liquid inlet end of the second reaction liquid phase runner is communicated with the second reaction liquid phase sample inlet, the liquid outlet end of the second reaction liquid phase runner is communicated with the liquid inlet end of the second heterogeneous reaction tank, the liquid outlet end of the first liquid outlet runner is communicated with the liquid inlet end of the second heterogeneous reaction tank, the liquid outlet end of the heterogeneous reaction tank is communicated with the second liquid outlet runner, and the liquid outlet end of the second liquid outlet runner is communicated with the mixed phase sample outlet; the active valve quantitative and uniform control unit comprises: the first active valve is arranged on the continuous liquid phase flow channel, the second active valve is arranged on the first liquid outlet flow channel, and the third active valve is arranged on the second liquid outlet flow channel; the first active valve includes: a valve plug, a gas phase sample inlet, a gas phase channel and a gas buffer chamber are arranged in the valve plug; the built-in valve plug is arranged in the continuous liquid-phase flow channel, the gas outlet end of the gas-phase channel is communicated with the gas buffer chamber, the gas inlet end of the gas-phase channel is communicated with the gas-phase sample inlet, and the gas buffer chamber corresponds to the built-in valve plug; the second active valve and the third active valve are both identical in structure to the first active valve.

The multistage reaction micro-channel structure provided by the application comprises a continuous outer triangular expansion focusing unit, an active valve quantitative uniform control unit and a multistage heterogeneous phase reaction unit, wherein the continuous outer triangular expansion focusing unit comprises a continuous liquid phase sample inlet, a continuous outer triangular expansion focusing channel and a continuous liquid phase channel, the continuous liquid phase sample inlet is used for introducing a sample (liquid drops or particles), the sample is separated layer by layer through the continuous outer triangular structure of the continuous outer triangular expansion focusing channel, so that the sample forms microspheres with the same size and distributed at equal intervals and enters the continuous liquid phase channel, inert gas is introduced into the continuous liquid phase channel through an air inlet channel, the distance of the microspheres is increased, the stability of the microsphere distributed at intervals is enhanced, the opening and closing degree of the continuous liquid phase channel is controlled through a first active valve of the active valve quantitative uniform control unit, thereby controlling the flow rate of the microspheres, realizing quantitative control and entering the mixed liquid phase channel, one of the mixed liquid phase channels is introduced through the first reaction liquid phase sample inlet, the mixed liquid phase channel is collected and fully reacted in a first heterogeneous phase reaction pool through the first reaction liquid phase channel, the second active valve controls the first active valve to control the first liquid phase channel to fully discharge the first liquid phase reaction liquid into the first heterogeneous reaction pool, the other homogeneous phase reaction channel is fully reacted through the first liquid phase reaction pool after the mixed liquid is completely introduced into the first liquid phase reaction pool, the second active valve controls the opening and closing degree of the first liquid outlet flow channel and the third active valve controls the opening and closing degree of the second liquid outlet flow channel, so that the reaction liquid in the second heterogeneous reaction tank can be subjected to full reaction, thereby realizing rapid and accurate quantitative control to perform accurate and efficient heterogeneous reaction, solving the technical problems of how to design a microfluidic device and an operation process, realizing rapid and accurate quantitative control to perform accurate and efficient heterogeneous reaction on the basis of generating high-dispersion liquid drops and particles, and improving the sufficiency of the reaction.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a top view of a multistage reaction microchannel structure provided in an embodiment of the present application;

FIG. 2 is a top view of a continuous outer triangular expanded focused runner provided in an embodiment of the present application;

FIG. 3 is a control schematic diagram of an active valve quantitative and uniform control unit in an embodiment of the application;

FIG. 4 is a top view of a multi-stage heterogeneous reaction cell unit provided in an embodiment of the present application;

fig. 5 is an overall structure diagram of a microfluidic chip provided in an embodiment of the present application.

The device comprises a continuous outer triangle expansion focusing unit 1, an active valve quantitative uniform control unit 2, a primary heterogeneous reaction tank unit 3, a secondary heterogeneous reaction tank unit 4, a continuous liquid phase sample inlet 5, a continuous outer triangle expansion focusing flow passage 6, a continuous liquid phase flow passage 7, a gas inlet 8, a gas inlet flow passage 9, a first reaction liquid phase sample inlet 10, a first reaction liquid phase flow passage 11, a first flow passage 110, a second flow passage 111, a first heterogeneous reaction tank 12, a first liquid outlet flow passage 13, a second reaction liquid phase sample inlet 14, a second reaction liquid phase flow passage 15, a third flow passage 150, a fourth flow passage 151, a second heterogeneous reaction tank 16, a second liquid outlet flow passage 17, a mixed phase sample outlet 18, a first active valve 19, a second active valve 20, a third active valve 21, a built-in valve plug 22, a gas phase sample inlet 23, a gas phase passage 24, a gas buffer chamber 25, a trapezoid valve block 26, a rectangular valve block 27, a base plate 28, a cover plate 29, a first transfer pump 30, a second transfer pump 31, a third transfer pump 32, a fourth transfer pump 33, a fifth transfer pump 34, a seventh transfer pump 35, a seventh transfer pump 36 and an extraction device 37.

Detailed Description

The following description of the embodiments of the present application will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.

In the description of the present application, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of description of the present application and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Unless specifically stated or limited otherwise, the terms "mounted," "connected," and "coupled" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art in a specific context.

For ease of understanding, referring to fig. 1 to 4, fig. 1 is a top view of a multistage reaction microchannel structure according to an embodiment of the present disclosure; FIG. 2 is a top view of a continuous outer triangular expanded focused runner provided in an embodiment of the present application; FIG. 3 is a control schematic diagram of an active valve quantitative and uniform control unit in an embodiment of the application; fig. 4 is a top view of a multi-stage heterogeneous reaction cell unit provided in an embodiment of the present application.

The embodiment of the application provides a multistage reaction micro-channel structure, including: the device comprises a continuous outer triangle expansion focusing unit 1, an active valve quantitative uniform control unit 2 and a multi-stage heterogeneous reaction tank unit;

the continuous outer triangle expansion focusing unit 1 includes: a continuous liquid phase sample inlet 5, a continuous outer triangle expansion focusing runner 6, a continuous liquid phase runner 7, an air inlet 8 and an air inlet runner 9;

the continuous liquid phase sample inlet 5 is communicated with the liquid inlet end of the continuous outer triangular expansion focusing flow passage 6, the liquid inlet end of the continuous liquid phase flow passage 7 is communicated with the liquid outlet end of the continuous outer triangular expansion focusing flow passage 6, the air outlet end of the air inlet flow passage 9 is communicated with the continuous liquid phase flow passage 7, and the air inlet end of the air inlet flow passage 9 is communicated with the air inlet 8;

the multi-stage heterogeneous reaction tank unit comprises a first-stage heterogeneous reaction tank unit 3 and a second-stage heterogeneous reaction tank unit 4;

The primary heterogeneous reaction tank unit 3 includes: the device comprises a first reaction liquid phase sample inlet 10, a first reaction liquid phase flow channel 11, a first heterogeneous reaction tank 12 and a first liquid outlet flow channel 13;

the liquid inlet end of the first reaction liquid-phase runner 11 is communicated with the first reaction liquid-phase sample inlet 10, the liquid outlet end is communicated with the liquid inlet end of the first heterogeneous reaction tank 12, the liquid outlet end of the continuous liquid-phase runner 7 is communicated with the liquid inlet end of the first heterogeneous reaction tank 12, and the liquid outlet end of the heterogeneous reaction tank is communicated with the liquid inlet end of the first liquid outlet runner 13;

the secondary heterogeneous reaction tank unit 4 includes: the second reaction liquid phase sample inlet 14, the second reaction liquid phase flow channel 15, the second heterogeneous reaction tank 16, the second liquid outlet flow channel 17 and the mixed phase sample outlet 18;

the liquid inlet end of the second reaction liquid-phase runner 15 is communicated with the second reaction liquid-phase sample inlet 14, the liquid outlet end is communicated with the liquid inlet end of the second heterogeneous reaction tank 16, the liquid outlet end of the first liquid-out runner 13 is communicated with the liquid inlet end of the second heterogeneous reaction tank 16, the liquid outlet end of the heterogeneous reaction tank is communicated with the second liquid-out runner 17, and the liquid outlet end of the second liquid-out runner 17 is communicated with the mixed phase sample outlet 18;

the active valve quantitative uniformity control unit 2 includes: a first active valve 19, a second active valve 20 and a third active valve 21, wherein the first active valve 19 is arranged on the continuous liquid phase flow channel 7, the second active valve 20 is arranged on the first liquid outlet flow channel 13, and the third active valve 21 is arranged on the second liquid outlet flow channel 17;

The first active valve 19 comprises: a built-in valve plug 22, a gas phase sample inlet 23, a gas phase channel 24 and a gas buffer chamber 25;

the built-in valve plug 22 is arranged in the continuous liquid-phase flow channel 7, the gas outlet end of the gas-phase channel 24 is communicated with the gas buffer chamber 25, the gas inlet end is communicated with the gas-phase sample inlet 23, and the gas buffer chamber 25 corresponds to the built-in valve plug 22;

the second active valve 20 and the third active valve 21 are each of the same construction as the first active valve 19.

It should be noted that, the inner side wall of the continuous outer triangle expansion focusing flow channel 6 is continuous zigzag, the overlook angle is similar to a plurality of continuous triangles, and the triangle is preferably equilateral triangle, so as to realize equally dispersing the sample and form more uniform microsphere particles, the narrowest part of the continuous outer triangle expansion focusing flow channel 6 is the same as the cross section of the continuous liquid phase flow channel 7, so that butt joint can be just performed, the bottom surface of the continuous outer triangle expansion focusing flow channel 6 is preferably a smooth wall surface, thus being beneficial to the flow of the sample, and the wall surface of the corresponding continuous liquid phase flow channel 7 can also be preferably a smooth wall surface. Preferably, in order to avoid damage to the wall surface caused by excessive pressure at the contact point of the gas phase channel 24 and the wall surface of the continuous liquid phase channel 7 due to direct contact of the gas phase channel 24 and the wall surface of the continuous liquid phase channel 7, a gas buffer chamber 25 is arranged to separate the gas phase channel 24 from the wall surface of the liquid phase channel, and the buffer chamber is kept at a certain distance from the wall surface of the liquid phase channel.

The primary heterogeneous reaction tank unit 3 comprises a first active valve 19, a terminal of a high-dispersion liquid drop (or microsphere) continuous liquid-phase flow passage 7, a first reaction liquid-phase sample injection flow passage, a first reaction liquid-phase sample injection port 10 and a first heterogeneous reaction tank 12 after quantitative and uniform control. The first reaction liquid phase sample inlet 10 and the first reaction liquid phase flow channel 11 are preferably two, and one first reaction liquid phase sample inlet 10 and one first reaction liquid phase flow channel 11 are matched, so that different reaction liquids can be added simultaneously, the functionality of the multistage reaction micro-channel structure is stronger, preferably, the first reaction liquid phase flow channel 11 comprises a first flow channel 110 and a second flow channel 111, one end of the first flow channel 110 is communicated with one end of the second flow channel 111, the other end of the first flow channel 110 is communicated with the first reaction liquid phase sample inlet 10, the other end of the second flow channel 111 is communicated with the liquid inlet end of the first heterogeneous reaction tank 12, the first flow channel 110 and the second flow channel 111 are in the same-diameter pipeline, the first flow channel 110 is in a horizontal trend, and the trend of the second flow channel 111 is in an included angle with the first flow channel 110. The caliber of the first liquid outlet flow channel 13 is larger than the caliber of the continuous liquid phase flow channel 7 and the caliber of the first reaction liquid phase flow channel 11, so that the flow of the first liquid outlet flow channel 13 is larger.

Preferably, the second heterogeneous reaction tank unit 4 comprises a second active valve 20, a first liquid outlet channel 13 end of the highly dispersed liquid drops (or microspheres), a second reaction liquid phase sample injection channel, a second reaction liquid phase sample injection port 14 and a second heterogeneous reaction tank 16 after quantitative and uniform control. The two second reaction liquid phase injection ports 14 and the two second reaction liquid phase flow channels 15 are preferably two, and one second reaction liquid phase injection port 14 and one second reaction liquid phase flow channel 15 are matched, so that different reaction liquids can be added simultaneously, the functionality of the multistage reaction micro-channel structure is stronger, preferably, the second reaction liquid phase flow channel 15 comprises a third flow channel 150 and a fourth flow channel 151, one end of the third flow channel 150 is communicated with one end of the fourth flow channel 151, the other end of the third flow channel 150 is communicated with the second reaction liquid phase injection port 14, the other end of the fourth flow channel 151 is communicated with the liquid inlet end of the second heterogeneous reaction tank 16, the third flow channel 150 and the fourth flow channel 151 are same-diameter pipelines, the third flow channel 150 is in a horizontal trend, and the trend of the fourth flow channel 151 and the third flow channel 150 form an included angle. The caliber of the second liquid outlet flow channel 17 is larger than the caliber of the second liquid outlet flow channel 17 and the caliber of the second reaction liquid phase flow channel 15, so that the flow rate of the second liquid outlet flow channel 17 is larger.

The multistage reaction micro-channel structure provided by the embodiment of the application, except for the multistage heterogeneous reaction tank unit comprising the first-stage heterogeneous reaction tank unit 3 and the second-stage heterogeneous reaction tank unit 4, can further comprise a third-stage heterogeneous reaction tank unit, a fourth-stage heterogeneous reaction tank unit and the like, and the specific stage number setting can be flexibly selected according to actual conditions, so that the purposes of multistage reaction, multistage detection, multi-step preparation and the like are achieved. The multistage reaction tank can be applied to preparing samples by a fractional precipitation method or performing various fractional (stage) reactions.

Preferably, the structure of the second active valve 20 is the same as that of the first active valve 19, specifically, the built-in valve plug 22 of the second active valve 20 is disposed in the liquid outlet channel, the gas outlet end of the gas phase channel 24 of the second active valve 20 is communicated with the buffer chamber of the second active valve 20, the gas inlet end is communicated with the gas phase inlet 23 of the second active valve 20, and the gas buffer chamber 25 of the second active valve 20 corresponds to the built-in valve plug 22 of the second active valve 20, thereby realizing the opening and closing control of the liquid outlet channel. The gas buffer chamber 25 of the first active valve 19 and the gas buffer chamber 25 of the second active valve 20 are preferably conical gas buffer chambers 25, the bottom of the conical gas buffer chambers 25 corresponds to the flow channel, and the distance between the conical gas buffer chambers 25 and the wall of the liquid phase flow channel is preferably 30 μm to 100 μm. The structure of the third active valve 21 is also the same as that of the first active valve 19, and will not be described again here.

The multistage reaction micro-channel structure provided by the application comprises a continuous outer triangular expansion focusing unit 1, an active valve quantitative uniform control unit 2 and a multistage non-uniform phase reaction unit, wherein the continuous outer triangular expansion focusing unit 1 comprises a continuous liquid phase sample inlet 5, a continuous outer triangular expansion focusing channel 6 and a continuous liquid phase channel 7, the continuous liquid phase sample inlet 5 is used for introducing samples (liquid drops or particles), the samples are separated layer by layer through the continuous outer triangular structure of the continuous outer triangular expansion focusing channel 6, so that the samples form microspheres which are identical in size and are distributed at equal intervals and enter the continuous liquid phase channel, inert gas is introduced into the continuous liquid phase channel 7 through an air inlet channel 9, the distance of the microspheres is increased, the spaced arrangement stability of the microspheres is enhanced, the opening and closing degree of the continuous liquid phase channel is controlled through a first active valve 19 of the active valve quantitative uniform control unit 2, thereby controlling the flow of the microspheres, realizing quantitative control, entering into a mixed liquid phase runner, introducing one of the reaction liquids into a first heterogeneous reaction tank 12 through a first reaction liquid phase runner 11, converging and fully reacting the reaction liquid, controlling the opening and closing degree of a first liquid outlet runner 13 through a second active valve 20 of an active valve quantitative uniform control unit 2, enabling a sample in the first heterogeneous reaction tank 12 and the reaction liquid to fully react, ensuring the sufficiency of the reaction, discharging from the first liquid outlet runner 13 and introducing into a second heterogeneous reaction tank 16 after the reaction is finished, introducing the other reaction liquid into the second heterogeneous reaction tank 16 through a human reaction liquid phase runner, converging and fully reacting the reaction liquid into the second heterogeneous reaction tank 16, the second active valve 20 controls the opening and closing degree of the first liquid outlet channel 13 and the third active valve 21 controls the opening and closing degree of the second liquid outlet channel 17, so that the reaction liquid in the second heterogeneous reaction tank 16 can be fully reacted, thereby realizing rapid and accurate quantitative control to perform accurate and efficient heterogeneous reaction, solving the technical problems of how to design a microfluidic device and an operation process, realizing rapid and accurate quantitative control to perform accurate and efficient heterogeneous reaction on the basis of generating high-dispersion liquid drops and particles, and improving the sufficiency of the reaction.

As a further improvement, the continuous outer triangular expansion focusing flow channel 6 of the multistage reaction micro flow channel structure provided by the embodiment of the application is spiral;

the liquid inlet end of the continuous outer triangle expansion focusing flow passage 6 is positioned at the center of the spiral shape;

the liquid outlet end of the continuous outer triangular expansion focusing flow passage 6 is positioned at the outer side of the spiral shape.

Specifically, the spiral structure is beneficial to the fact that the length of the continuous outer triangle expansion flow channel is the largest under the condition of occupying area as small as possible, so that the separation and dispersion effects on samples are better, the introduced samples can be relatively turbulent fluids such as focused liquid drops or liquid drops wrapping particles, after entering the continuous outer triangle expansion focusing flow channel, turbulent fluids containing particles flow along the inner wall surface of the triangle under the simultaneous action of centrifugal force and Dien flow force, and finally high-dispersion and stable arrangement is realized, so that the focusing flow can be effectively increased, and the dispersion stability is improved.

As a further improvement, the embodiment of the present application provides at least one first active valve 19 and at least one second active valve 20 of the active valve quantitative uniformity control unit 2 of the multistage reaction micro-channel structure. Two first driving valves 19 are preferably arranged, so that the flow in the continuous liquid phase flow channel 7 is controlled in a grading manner, the flow in the continuous liquid phase flow channel 7 is reduced step by step, the final flow is controlled more accurately, the two first driving valves 19 are arranged in parallel front and back, and the two second driving valves 20 are identical in function with the two first driving valves 19, and are not described herein.

As a further improvement, the built-in valve plug 22 provided in the embodiment of the present application includes a trapezoid valve block 26 and a rectangular valve block 27;

the trapezoid valve block 26 is arranged on one side of the inner wall of the continuous liquid-phase flow channel 7 far away from the gas buffer chamber 25, and the bottom surface of the trapezoid valve block 26 is attached to the inner wall of the continuous liquid-phase flow channel 7;

the rectangular valve blocks 27 are arranged on one side, close to the gas buffer chamber 25, of the inner wall of the continuous liquid phase flow channel 7, the rectangular valve blocks 27 and the trapezoid valve blocks 26 are distributed in a staggered mode, and the side walls of the rectangular valve blocks 27 corresponding to the trapezoid valve blocks 26 are located on the same section of the continuous liquid phase flow channel 7.

Specifically, when the gas buffer chamber 25 is inflated, the flow channel (which may be the continuous liquid-phase flow channel 7 or the first liquid-outlet flow channel 13 or the second liquid-outlet flow channel 17) is extruded through the bottom of the gas buffer chamber 25, so that the flow channel is deformed and drives the rectangular valve block 27 to move and approach the trapezoid valve block 26, so that the flow port of the flow channel is gradually reduced, the flow rate can be controlled, and when the rectangular valve block 27 is closely attached to the trapezoid valve block 26, the flow channel is closed.

As a further improvement, the materials of the gas buffer chamber 25 and the continuous liquid flow channel 7 provided in the embodiments of the present application are deformable materials, the gas buffer chamber 25 does not deform in a non-inflated state, the gas buffer chamber 25 expands in an inflated state and abuts against one side of the continuous liquid flow channel 7, and the inner wall of the continuous liquid flow channel 7 is fully contacted with the built-in valve plug 22, so that blocking of the continuous liquid flow channel 7 is realized. Specifically, the gas source in the gas phase channel 24 is from the gas introduced by the gas phase inlet 23, and the gas phase inlet 23 can be externally connected with a gas pump and other devices.

As a further improvement, the cross sections of the continuous liquid-phase flow channel 7, the gas-phase flow channel 24, the first reaction liquid-phase flow channel 11, the second reaction liquid-phase flow channel 15, the first liquid-outlet flow channel 13 and the second liquid-outlet flow channel 17 provided in the embodiment of the present application are all rectangular, and the various flow channels are highly uniform.

Preferably, the total length of the continuous outer triangular expansion focusing runner 6 is 200 mm-2000 mm; the width of the continuous outer triangle expansion focusing flow passage 6 is 100-200 μm; the distance between two adjacent channels of the continuous outer triangular expansion focusing channel 6 is 200-400 μm; the radius of curvature of the innermost runner of the continuous outer triangular expansion focusing runner 6 is 20 mm-60 mm.

Further, the side walls of the first heterogeneous reaction tank 12 and the second heterogeneous reaction tank 16 are circular side walls, and the circular radius of the two side walls is 100 um-200 um.

Referring to fig. 1 to 5, the present application further provides a microfluidic chip, which includes a chip body and the multistage reaction micro-channel structure in the above embodiment; the multistage reaction micro-channel structure is arranged in the chip body.

Alternatively, the material of the chip body is preferably PDMS made of transparent material, and the chip body can be directly observed and photographed by using a microscope.

As a further improvement, the chip body of the microfluidic chip provided in the embodiment of the present application includes a substrate 28 and a cover plate 29; the multistage reaction micro-channel structure is arranged on the upper surface of the substrate 28; the cover 29 covers the upper surface of the substrate 28, and the continuous liquid phase sample inlet 5, the gas phase sample inlet 23, the reaction liquid phase sample inlet and the mixed phase sample outlet 18 are all penetrated through the cover 29.

As a further improvement, the microfluidic chip provided in the embodiment of the present application further includes a conveying device and an extracting device 37; the conveying device comprises a first conveying pump 30 communicated with the continuous liquid phase sample inlet 5, a second conveying pump 31 communicated with the gas phase sample inlet 23 of the first active valve 19, a third conveying pump 32 communicated with the first reaction liquid phase sample inlet 10, a fourth conveying pump 33 communicated with the gas phase sample inlet 23 of the second active valve 20, a fifth conveying pump 34 communicated with the second reaction liquid phase sample inlet 14, a sixth conveying pump 35 communicated with the gas phase sample inlet 23 of the third active valve 21 and a seventh conveying pump 36 communicated with the gas inlet 8; the extraction device 37 communicates with the mixed phase outlet 18. Wherein, the first delivery pump 30 is used for delivering the sample into the continuous liquid phase sample inlet 5; the seventh transfer pump 36 is used for transferring inert gas into the air inlet channel 9, and into the continuous liquid phase channel 7 through the air inlet channel 9; the second transfer pump 31 is used for transferring gas into the gas phase sample inlet 23 of the first active valve 19; the third transfer pump 32 is used for transferring the reaction liquid into the first reaction liquid phase sample inlet 10, the fourth transfer pump 33 is used for transferring the gas into the gas phase sample inlet 23 of the second driving valve 20, the fifth transfer pump 34 is used for transferring the other reaction liquid into the second reaction liquid phase sample inlet 14, and the sixth transfer pump 35 is used for transferring the gas into the gas phase sample inlet 23 of the third driving valve 21, specifically, since two first reaction liquid phase sample inlets 10 and first reaction liquid phase flow channels 11 are preferably used, one first reaction liquid phase sample inlet 10 and one first reaction liquid phase flow channel 11 are matched, two third transfer pumps 32 can be preferably used, and each third transfer pump 32 can be respectively communicated with one first reaction liquid phase sample inlet 10 and is used for transferring the same or different reaction liquids to the corresponding first reaction liquid phase sample inlet 10. Since two second reaction liquid phase injection ports 14 and two second reaction liquid phase flow channels 15 are preferred, and one second reaction liquid phase injection port 14 and one second reaction liquid phase flow channel 15 are matched, two fifth transfer pumps 34 may be preferred, and each fifth transfer pump 34 may be respectively communicated with the second reaction liquid phase injection port 14 and used for transferring the same or different reaction liquids to the corresponding second reaction liquid phase injection port 14. Preferably, since the number of the first active valves 19 is preferably two, the number of the second transfer pumps 31 is also preferably two, and the two first active valves 19 are respectively matched, so that independent control of the two first active valves 19 is realized. Since the number of the second active valves 20 is preferably two, the number of the fourth transfer pumps 33 is also preferably two, and is matched with the two second active valves 20, respectively, so that independent control of the two second active valves 20 is achieved.

The microfluidic chip is highly integrated, and the whole chip area is small and only has a plurality of cubic centimeters; the microfluidic chip has low cost and simple structure, and is easy for mass production.

The microfluidic chip provided by the application has the following advantages:

1. the device structure is miniaturized and has strong compatibility with other equipment. The whole microfluidic chip device has small area but large specific surface area, and realizes high flux.

2. Can be widely applied to various heterogeneous reactions. A plurality of reaction units can be simultaneously used through a series or parallel micro-channel network, and meanwhile, the reaction units are mutually isolated, and the reactions are not mutually interfered. The application field is wide. Because the liquid-phase flow channel and the gas-phase flow channel are not communicated, the gas can not react with the reaction liquid and the particles, and the method is suitable for various heterogeneous reactions.

3. The device material is highly replaceable. Such as glass chips, metal chips can be used as the chip material.

4. The controlled solid particles have high dispersion stability. The continuous outer triangle expansion focusing flow passage is more beneficial to passive Dien flow inertial focusing, effectively increases focusing paths and regulates and controls inertial force stress at the same time, thereby improving the dispersibility and stability of particles.

5. And 3, the materials in the reaction tank are accurately and quantitatively controlled. The pressure of the conical gas buffer chamber is controlled by adjusting the pneumatic pump so as to rapidly control the quantity of solid particles in the continuous liquid phase, thereby realizing precise and controllable quantitative control.

6. The reaction is uniform and full. The heterogeneous reaction can be ensured to be uniformly and fully carried out in the reaction tank by adjusting the opening and closing of the front and rear active control valves of the heterogeneous reaction tank.

7. Is environment-friendly and low in cost. The used chip materials are nontoxic and harmless, and the reaction effect can be hardly achieved by the conventional operation only by less particles and reaction liquid in the operation process.

8. Is easy to observe. The device can select PDMS of transparent material as the chip material, can directly use the microscope to observe, record of shooing.

9. Safe, reliable, high-speed and high-efficiency reaction.

The application also provides a heterogeneous reaction method which is applied to the multistage reaction micro-channel structure of any one of claims 1-6, and is characterized by comprising the following steps:

s1, uniformly and stably dispersing microsphere suspension liquid through a continuous outer triangular expansion focusing flow channel, flowing into a continuous liquid phase channel, and guiding the microsphere suspension liquid into a first heterogeneous reaction tank through the continuous liquid phase channel;

s2, adjusting the flow of the continuous liquid phase channel through a first active valve of an active valve quantitative uniform control unit, and accurately controlling the quantity of microspheres in microsphere suspension flowing into a first heterogeneous reaction tank;

S3, enabling a reaction liquid to enter a first heterogeneous reaction tank through a first reaction liquid flow channel, enabling the reaction liquid to enter the first heterogeneous reaction tank for reaction after being in short contact with a first heterogeneous microsphere suspension, and transmitting the reaction liquid to a second heterogeneous reaction tank through a first liquid outlet flow channel;

s4, adjusting the flow of the first liquid outlet flow passage through a second active valve of the active valve quantitative uniform control unit;

s5, enabling the other reaction liquid to enter a second heterogeneous reaction tank through a second reaction liquid flow channel, fully reacting with substances in the second heterogeneous reaction tank, and discharging the reacted substances from a second liquid flow channel;

s6, adjusting the flow of the second liquid outlet flow passage through a third active valve of the active valve quantitative uniform control unit.

The first embodiment provided in the present application is the following second embodiment provided in the present application, specifically:

the chip body is made of PDMS (polydimethylsiloxane), wherein the length of the continuous outer triangle expansion focusing flow passage is 1200mm, the distance between two adjacent vortex focusing flow passages is 100 mu m, the radius of curvature of the innermost flow passage is 40mm, the widths of the gas phase flow passage, the first reaction liquid phase flow passage, the continuous liquid phase flow passage and the second reaction liquid flow passage are 100 mu m, the widths of the first liquid outlet flow passage and the second liquid outlet flow passage are 100 mu m, the distance between the gas buffer chamber and the continuous liquid phase flow passage is 60 mu m when the gas buffer chamber is in a non-working state, and the heights of all flow passages are 150 mu m. Nitrogen is selected as a gas phase, a proper amount of carbon spheres with the particle size of 50 mu m are added into a mixed water solution of magnesium nitrate and calcium nitrate to form microsphere suspension, and an ammonium carbonate water solution and a sodium hydroxide water solution are respectively used as reaction solutions in a primary heterogeneous reaction tank unit and a secondary heterogeneous reaction tank unit. Microsphere suspension and reaction solution were injected into the chip using polytetrafluoroethylene capillary tubing, respectively, and gas phase fluid was controlled using a pneumatic pump. The flow rate of the microsphere suspension is 50 mu l/min, the gas phase flow rate is 80 mu l/min, and the flow rates of the reaction liquid in the first reaction liquid flow channel, the first liquid outlet flow channel and the second reaction liquid flow channel are all 40 mu l/min. The quantitative carbon spheres in the microsphere suspension liquid and the ammonium carbonate aqueous solution enter a first heterogeneous reaction tank together by adjusting the flow rates of the gas phase and the microsphere suspension liquid, all active valves in the front and the back of the reaction tank are closed, so that the ammonium carbonate solution, the cobalt nitrate and the mixed aqueous solution of calcium nitrate with the carbon spheres are subjected to precise, efficient and sufficient heterogeneous reaction, and calcium hydroxide precipitation is uniformly attached to the surface of a carbon sphere template. And opening front and rear active valves of the first heterogeneous reaction tank, regulating the flow of gas phase and calcium hydroxide/carbon sphere suspension liquid to control the quantity of particles, simultaneously introducing sodium hydroxide aqueous solution into the third flow passage and the fourth flow passage to enable the sodium hydroxide aqueous solution to jointly enter the second heterogeneous reaction tank, closing the front and rear active valves of the second heterogeneous reaction tank, and carrying out uniform and sufficient secondary reaction in the tank to generate the (calcium hydroxide-cobalt hydroxide)/carbon sphere. And then the obtained substance is led out from the third mixed phase sample outlet.

The above is a second embodiment provided by the present application, and the following is a third embodiment provided by the present application, specifically:

the chip body is made of PDMS, wherein the length of the continuous outer triangle expansion focusing flow passage is 1600mm, the distance between two adjacent vortex focusing flow passages is 80 mu m, the radius of curvature of the innermost flow passage is 50mm, the widths of the gas phase flow passage, the first reaction liquid phase flow passage, the continuous liquid phase flow passage and the second reaction liquid flow passage are 120 mu m, the widths of the mixed liquid phase flow passage and the liquid outlet flow passage are 160 mu m, the gas buffer chamber is kept at a certain distance from the wall of the liquid phase flow passage in a non-working state, the distance is 80 mu m, and the heights of all flow passages are 200 mu m. Nitrogen is selected as a gas phase, a proper amount of carbon spheres with the particle size of 50 mu m are added into a mixed water solution of magnesium nitrate and calcium nitrate to form microsphere suspension, and an ammonium carbonate water solution and a sodium hydroxide water solution are respectively used as reaction solutions in a primary heterogeneous reaction tank unit and a secondary heterogeneous reaction tank unit. Microsphere suspension and reaction solution were injected into the chip using polytetrafluoroethylene capillary tubing, respectively, and gas phase fluid was controlled using a pneumatic pump. The flow rate of the microsphere suspension is 60 mu l/min, the gas phase flow rate is 80 mu l/min, and the flow rates of the reaction liquid in the first reaction liquid flow channel, the first liquid outlet flow channel and the second reaction liquid flow channel are all 50 mu l/min. The quantitative carbon spheres in the microsphere suspension liquid and the ammonium carbonate aqueous solution enter a first heterogeneous reaction tank together by adjusting the flow rates of the gas phase and the microsphere suspension liquid, all active valves in the front and the back of the reaction tank are closed, so that the ammonium carbonate solution, the cobalt nitrate and the mixed aqueous solution of calcium nitrate with the carbon spheres are subjected to precise, efficient and sufficient heterogeneous reaction, and calcium hydroxide precipitation is uniformly attached to the surface of a carbon sphere template. And opening front and rear active valves of the first reaction tank unit, regulating the flow of gas phase and calcium hydroxide/carbon sphere suspension liquid to control the quantity of particles, simultaneously introducing sodium hydroxide aqueous solution into the third flow passage and the fourth liquid flow passage to enable the sodium hydroxide aqueous solution to jointly enter the second heterogeneous reaction tank, closing the front and rear active valves of the second heterogeneous reaction tank, and carrying out uniform and sufficient secondary reaction in the tank to generate (calcium hydroxide-magnesium hydroxide)/carbon spheres. And then the obtained substances are led out from the mixed phase sample outlet.

The above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. Multistage reaction microchannel structure, its characterized in that includes: the device comprises a continuous outer triangle expansion focusing unit, an active valve quantitative uniform control unit and a multi-stage heterogeneous reaction tank unit;

the liquid inlet end of the first reaction liquid phase runner is communicated with the first reaction liquid phase sample inlet, the liquid outlet end of the first reaction liquid phase runner is communicated with the liquid inlet end of the first heterogeneous reaction tank, the liquid outlet end of the continuous liquid phase runner is communicated with the liquid inlet end of the first heterogeneous reaction tank, and the liquid outlet end of the heterogeneous reaction tank is communicated with the liquid inlet end of the first liquid outlet runner;

the liquid inlet end of the second reaction liquid phase runner is communicated with the second reaction liquid phase sample inlet, the liquid outlet end of the second reaction liquid phase runner is communicated with the liquid inlet end of the second heterogeneous reaction tank, the liquid outlet end of the first liquid outlet runner is communicated with the liquid inlet end of the second heterogeneous reaction tank, the liquid outlet end of the heterogeneous reaction tank is communicated with the second liquid outlet runner, and the liquid outlet end of the second liquid outlet runner is communicated with the mixed phase sample outlet;

the second active valve and the third active valve are identical to the first active valve in structure;

the built-in valve plug comprises a trapezoid valve block and a rectangular valve block;

2. The multi-stage reaction microchannel structure according to claim 1, wherein the continuous outer triangular expanded focusing channel is spiral;

3. The multi-stage reaction microchannel structure according to claim 1, wherein at least one of the first active valves and at least one of the second active valves is provided.

4. The multistage reaction microchannel structure according to claim 1, wherein,

the gas buffer chamber and the continuous liquid phase runner are made of deformable materials, the gas buffer chamber is not deformed in a non-inflated state, and the gas buffer chamber expands in an inflated state and is abutted against one side of the continuous liquid phase runner, so that the inner wall of the continuous liquid phase runner is fully contacted with the built-in valve plug, and the blocking of the continuous liquid phase runner is realized.

5. The multistage reaction microchannel structure according to claim 1, wherein the cross sections of the continuous liquid-phase channel, the gas-phase channel and the reaction liquid-phase channel are rectangular, the heights of the various channels are uniform, and the heights are 100 μm to 200 μm.

6. The multi-stage reaction microchannel structure according to claim 1, wherein the sidewalls of the first heterogeneous reaction cell and the second heterogeneous reaction cell are circular sidewalls.

7. A microfluidic chip comprising a chip body and the multistage reaction microchannel structure of any one of claims 1-6;

the multistage reaction micro-channel structure is arranged in the chip body.

8. The microfluidic chip according to claim 7, wherein the chip body comprises a substrate and a cover plate;

9. The microfluidic chip according to claim 7, further comprising a delivery device and an extraction device;

The extraction device is communicated with the mixed phase sample outlet.

10. A heterogeneous reaction method applied to the multistage reaction microchannel structure according to any one of claims 1 to 6, characterized by comprising the steps of: