CN114733586A

CN114733586A - Microparticle flow focusing device and method

Info

Publication number: CN114733586A
Application number: CN202210228904.4A
Authority: CN
Inventors: 陈华英; 徐正; 陈思远; 陈震林
Original assignee: Zhuhai Ontario Technology Co ltd
Current assignee: Zhuhai Ontario Technology Co ltd
Priority date: 2022-03-09
Filing date: 2022-03-09
Publication date: 2022-07-12
Anticipated expiration: 2042-03-09
Also published as: WO2023168775A1; CN114733586B

Abstract

The invention relates to a microparticle flow focusing device and a method, comprising the following steps: the micro-pore mechanism comprises a plurality of micro-pores arranged in rows, and a micro-particle inlet is arranged at the starting end of the first flow channel. The microparticle flow sorting device and the microparticle flow sorting method disclosed by the invention can realize one-dimensional focusing of microparticles without sheath flow, and the focusing effect is better at low flow velocity, so that the microparticle flow sorting device and the microparticle flow sorting method have no damage to the activity of mammalian cells. In addition, the method and the device can also be used for focusing micro samples, and have obvious advantages compared with the traditional focusing based on sheath flow.

Description

Microparticle flow focusing device and method

Technical Field

The invention relates to a micro-particle flow focusing device and a micro-particle flow focusing method, and belongs to the field of biomedical analysis.

Background

In biomedical analysis, only specific particles (microspheres or cells) in a sample, such as circulating tumor cells in a blood sample or healthy cells in a cell culture medium, are often studied. These particles generally have specific properties, and can therefore be detected and sorted out using these properties.

Flow cytometry has been widely used as a powerful analytical tool for many diseases over the past 20 years due to its ability to detect and sort cells. It utilizes laser or impedance-based techniques for cell counting or sorting, by suspending cells in a fluid through an optical or electrical device testing apparatus, and downstream for further sorting operations, an important tool for biological analysis. Conventional flow cytometers are bulky, expensive and complex to operate, and in order to overcome these disadvantages, researchers have introduced the concept of microfluidics into flow cytometry, which is referred to as microfluidic flow cytometry. Microfluidics is a technique for manipulating fluids in channels with dimensions in the range of tens of micrometers. Similar to conventional flow cytometers, microfluidic flow cytometers also consist of five major subsystems, where sample pumping, focusing and sorting can be mostly done on microfluidic chips. The micro-fluidic chip has a small size, which can greatly reduce the volume of the required sample and reagent. And its integration into a system, can reduce the overall size and maintenance requirements of the device, and as such, in combination with microfluidics is considered to be a future development direction for flow cytometers.

The detection capability of a single cell is one of the main features and capabilities of a flow cytometer. When cells are injected into a flow cytometer, it is necessary to focus the sample into a narrow core stream that can be passed through the detection zone one by one at a rate, which is the pre-processing stage of the flow cytometer. Focusing can be divided into active focusing, which relies on the inherent properties of the fluid to achieve microparticle focusing, and passive focusing, which often relies on external fields to generate driving forces, including Acoustophoresis (AP), Dielectrophoresis (DEP), Magnetoelectrophoresis (MP), and fluorescence-activated separation methods. Active focusing often requires the introduction of an external device, which increases the complexity of the device and may cause damage to the cells. For example, the traditional flow cytometer uses sheath flow to focus the sample flow, and after the microfluidic chip appears, the sheath flow is introduced through a smart structural design. The sheath flow compresses the sample flow from all sides to the middle, which can achieve precise control of the sample flow, but requires a large amount of sheath flow reagents, and the sheath flow flowing at high speed may also damage the cells. Inertial microfluidics is a passive focusing method that uses inertial lift to drive particles to one or more equilibrium positions of a microchannel to achieve the focusing function. The device needs a long length and a high speed to focus, the focusing accuracy is poor, and the method cannot be combined with a detection system to realize high-precision single cell separation. Researchers have also designed a spiral microfluidic device that can directly focus particles at different positions according to size and then directly sort the particles. To avoid the large spiral layout, researchers have designed a straight channel microfluidic chip containing a contraction and expansion array using inertial microfluidics. However, the problems of high flow rate and low focusing resolution caused by inertial microfluidics are still unavoidable. Other passive focusing, such as Deterministic Lateral Displacement (DLD), are as difficult as inertial microfluidics to achieve deterministic sorting by subsequent detection of particles.

In summary, the flow cytometry mostly adopts sheath flow focusing microparticles, but the sheath flow increases the complexity of the microfluidic chip, and needs a large amount of additional sheath fluid, and the sheath fluid flowing at high speed may also cause cell damage; the active focusing device needs to introduce an external physical field such as sound, light, electricity, magnetism and the like, the focusing mode greatly increases the focusing complexity, and the intervention of the external physical field can cause damage to the cell per se and influence the activity of the cell; other passive focusing, while not introducing an external physical field, have low inertial microfluidic resolution and require high flow rates and long focal lengths. Other passive focusing such as DLD is difficult to combine with image, fluorescence and telecommunications to achieve deterministic sorting.

Disclosure of Invention

The present invention provides a focusing device and method for particle flow, which at least solves one of the technical problems in the prior art.

The technical scheme of the invention is a microparticle flowing focusing device, which comprises: the micro-pore mechanism comprises a plurality of micro-pores arranged in rows, and a micro-particle inlet is arranged at the starting end of the first flow channel.

Further, still include: the micro-particle sorting system comprises a micro-particle sorting area, a sorting device and a control device, wherein the micro-particle sorting area comprises a plurality of sorting flow channels, and the tail ends of the sorting flow channels are communicated with a sorting outlet; and valve switching mechanisms correspondingly arranged near the sorting flow channels, wherein the starting ends of the sorting flow channels are communicated with the tail ends of the first flow channels.

Furthermore, the micropore mechanism also comprises a second flow passage, and the connected micropores are communicated through the second flow passage.

Furthermore, the micropores are respectively mirror-symmetrical with the central axis of the first flow channel.

Furthermore, a plurality of adjacent second flow passages and the micropores are symmetrically arranged along a central axis in the flowing direction, and the cross section of each micropore comprises one or more of a circle, an ellipse, a triangle or a rhombus which can converge streamline shapes.

Further, valve switch mechanism includes force pump and thin layer, the middle part of thin layer is equipped with many air flues, the both ends of air flue are equipped with into gas port and gas outlet respectively, the high-pressure outlet and the low pressure entry of force pump communicate with income gas port and gas outlet respectively, wherein, the surface at chip layer mechanism is connected in the thin layer bonding, each the air flue corresponds and spanes the top of selecting separately the runner top, the bottom surface of air flue is the switch layer with the crossing part of selecting separately the runner, when the high-pressure outlet of force pump lets in high-pressure gas to the air flue, the switch layer receives the bottom surface inflation of high-pressure gas extrusion to selecting separately the runner, makes the switch layer block up selects separately the runner, when the gas outlet of force pump flowed high-pressure gas, the deformation on switch layer recovers the mediation of messenger and selects separately the runner.

Furthermore, the microparticle focusing region further comprises a transition flow channel, one end of the transition flow channel is communicated with the first flow channel from the starting end of the separation flow channel to the microparticle inlet direction, and the other end of the transition flow channel is connected with the tail end of the first flow channel.

Further, valve switch mechanism includes force pump and control fluid channel, control fluid channel sets up the inside of chip layer mechanism, control fluid channel's one end and the top intercommunication of selecting separately the runner, the pressure port and the other end intercommunication of control fluid channel of force pump.

A method for focusing and actively sorting a micro-particle flow, according to the working method of the device, wherein the device comprises a detection mechanism arranged at the end of the first flow channel, the method comprises the following steps:

s100, introducing liquid and microparticles through the initial end of the microparticle focusing area, and enabling the microparticles to flow through a first flow channel from the initial end to the tail end of the microparticle focusing area;

s200, enabling the micro-particles to pass through a plurality of micro-holes arranged in at least one row from the first flow channel in sequence and focus on the tail end of a micro-particle focusing area along a straight line;

s300, after the detection mechanism identifies the attributes of the micro-particles, the opening or closing of the valve opening and closing mechanism is controlled to actively control the micro-particles with different attributes to flow into the corresponding sorting flow channels, and sorting of the micro-particles is completed.

The invention has the beneficial effects that:

1. the micro-particle flow focusing device has good focusing effect and can realize one-dimensional focusing on micro-particles.

2. Compared with inertial microfluidics, the device provided by the invention has the advantages that the required channel length is short, the size of the device can be reduced, the device can realize the focusing of particles without high flow velocity, the device can be applied to a plurality of low-flow-velocity scenes, and the accurate detection and sorting of the particles can be realized.

3. The microparticle sorting method can select different detection mechanisms for sorting based on the difference of the size, fluorescence and electric signals of the microparticles.

Drawings

Fig. 1 is a top view of a microparticle flow focusing apparatus according to an embodiment of the present invention.

Fig. 2 is a top view of a focusing region of micro-particles according to an embodiment of the present invention.

FIG. 3 is a top view of a micro-well and a second flow channel connection according to an embodiment of the invention.

FIG. 4 is a perspective view of a micro-well and a second flow channel connection according to an embodiment of the present invention.

FIG. 5 is a top view of different shaped micro-particles and a second flow channel connection according to an embodiment of the present invention.

FIG. 6 is a cross-sectional view of a first fluid channel and a micro-well according to a first embodiment of the invention.

FIG. 7 is a cross-sectional view of a second embodiment of a microwell and first fluid channel connection in accordance with the present invention.

Fig. 8 is a schematic view of a microparticle flow sorting device according to an embodiment of the present invention.

Fig. 9 is a schematic diagram illustrating the connection between the microparticle focusing region and the microparticle sorting region according to an embodiment of the present invention.

Fig. 10 is a schematic diagram of an external configuration of a micro-particle flow focusing and sorting connection valve according to an embodiment of the present invention.

FIG. 11 is a schematic view showing the connection between the valve opening and closing mechanism and the external structure according to the embodiment of the present invention.

Fig. 12 is a sectional view of a valve opening and closing mechanism and an external structure according to an embodiment of the present invention.

Fig. 13 is an enlarged view of a portion of the AA of fig. 5, in accordance with an embodiment of the present invention.

Detailed Description

The conception, the specific structure and the technical effects produced by the present invention will be clearly and completely described in conjunction with the embodiments and the attached drawings, so as to fully understand the objects, the schemes and the effects of the present invention. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

It should be noted that, unless otherwise specified, when a feature is referred to as being "fixed" or "connected" to another feature, it may be directly fixed or connected to the other feature or indirectly fixed or connected to the other feature. Furthermore, the descriptions of upper, lower, left, right, top, bottom, etc. used in the present invention are only relative to the positional relationship of the components of the present invention with respect to each other in the drawings.

Furthermore, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any combination of one or more of the associated listed items.

It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element of the same type from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of the present disclosure.

Referring to fig. 1 to 13, in some embodiments, the present disclosure discloses a microparticle flow sorting apparatus, including: a chip layer mechanism 1000, wherein a micro particle focusing region 1100 is arranged inside the chip layer mechanism 1000. Referring to fig. 1, a section of the chip layer mechanism 1000 is a micro-particle focusing region 1100.

Referring to the microparticle focusing region 1100 shown in fig. 1 to 4, the upper layer and the lower layer of the microparticle focusing region 1100 are respectively provided with a first flow channel 1110 and at least one row of micro-porous mechanisms 1120 corresponding to the lower side of the first flow channel 1110. In the microparticle focusing region in fig. 4, it is seen that the microparticles are gradually focused in the arrow direction, and the three rightmost microparticles are located in the first flow channel 1110. Referring to fig. 5, a first channel 1110 and a micro-porous structure 1120 corresponding to a row below the first channel 1110 are disposed on the upper layer and the lower layer of the micro-particle focusing region 1100, respectively.

Referring to fig. 2 in conjunction with fig. 4, the micro-hole mechanism 1120 includes a plurality of micro-holes 1121 arranged in a row, and the connected micro-holes 1121 are communicated with each other through a second flow channel 1122. Referring to fig. 1, a fine particle inlet 1111 is provided at a start end of the first channel 1110.

The micro-particles to be focused are input with the liquid through the micro-particle inlet 1111 at the beginning of the first flow channel 1110, the micro-particles gradually pass through at least one row of micro-pore mechanisms 1120 at the lower layer of the first flow channel 1110 at the upper layer, because the lower layer has a plurality of micro-pores 1121 and is communicated through the second flow channel 1122, the micro-particles settle through the micro-pores 1121 under the action of gravity and flow lines, rise through the second flow channel 1122, and gradually deflect towards the middle line until the micro-particles completely focus on the central axis position of the micro-pores 1121. When the micro-particles pass through the multi-row micro-particle mechanism 1120, a large number of micro-particles flowing from the upstream are focused into a plurality of rows of fine wire bundles without changing the flow speed, the micro-particles are further gathered into a bundle through the arrangement of the micro-holes 1121 in the downstream, and finally all the micro-particles can flow to the end of the first flow channel 1110 along a straight line.

Referring to fig. 1 and the microparticle sorting region 1200 shown in fig. 8, the microparticle sorting region 1200 includes a plurality of sorting channels 1220, the ends of the sorting channels 1220 are connected to a sorting outlet 1221, and both ends of the waste liquid channel 1210 are connected to a waste liquid outlet 1211.

Referring to fig. 9, two sorting channels 1220 are drawn from the first channel 1110 corresponding to the valve switching mechanisms 2000 disposed near each sorting channel 1220, and then the respective valve switching mechanisms 2000 are disposed on the two sorting channels 1220 to control whether the microparticles enter a specific sorting channel 1220.

The straight line of the end of the focusing region for the particles leaves the particles, the particles with different attributes are classified, and the opening and closing of the valve opening and closing mechanism 2000 are controlled to make the particles with different attributes enter the specific sorting flow channel 1220, so that the region completes the classification of the particles.

Referring to fig. 1 to 5 in combination with fig. 13, the micro-hole mechanism 1120 further includes a second flow channel 1122, the micro-holes 1121 are connected and communicated through the second flow channel 1122, and a plurality of adjacent second flow channels 1122 and micro-holes 1121 are symmetrically arranged along a central axis of a flow direction, so as to facilitate focusing of the micro-particles in a step-by-step manner during a flow process of each micro-hole.

Referring to fig. 5 to 7, the cross-sectional shapes of the micro-holes 1121 include one or more of a circle, an ellipse, a triangle, or a diamond, the micro-holes 1121 may also be formed in other converging streamline shapes, and the whole device may also be adapted to a specific application scenario of focusing the micro-particles by adjusting the shapes, heights, and arrangement of the micro-holes.

Referring to fig. 9 to 12, the valve switching mechanism 2000 includes a pressure pump 2100 and a thin film layer 2200, wherein the thin film layer 2200 is a PDMS thin film having a thickness of 9 to 11 μm.

Referring to fig. 9 to 12, a plurality of air passages 2210 are formed in the middle of the film layer 2200, an air inlet 2211 and an air outlet 2212 are formed at both ends of the air passages 2210, and a high pressure outlet 2110 and a low pressure inlet 2120 of the pressure pump 2100 are respectively communicated with the air inlet 2211 and the air outlet 2212.

Referring to fig. 9, the thin film layer 2200 is bonded to the surface of the chip layer mechanism 1000, and each air passage 2210 correspondingly crosses over the beginning of the sorting channel 1220. Referring to fig. 13, a portion where the bottom surface of the air passage 2210 intersects the sorting flow path 1220 is a switching layer 2213.

Referring to the embodiment shown in fig. 10, an air passage 2210 is connected to a pressure pump 2100, a syringe pump 4000 is connected to a microparticle inlet 1111 via a pipe to input flowing liquid, and a sorting channel 1220 is connected to a container to collect the liquid output from the syringe pump 4000.

When the high pressure outlet 2110 of the pressure pump 2100 introduces high pressure gas into the gas passage 2210, the switch layer 2213 is pressed by the high pressure gas to expand toward the bottom surface of the sorting flow channel 1220, so that the switch layer 2213 blocks the sorting flow channel 1220, and when the high pressure gas flows out from the gas outlet 2212 of the pressure pump 2100, the deformation of the switch layer 2213 is restored to dredge the sorting flow channel 1220. The micro-particles enter the corresponding sorting flow channels along with the opening and closing of the switch layer 2213, and the structure of the sorting valve is simple to operate.

Referring to fig. 1 and 2, the particle focusing region 1100 further includes a transition flow channel 1130. One end of the transition flow channel 1130 is connected to the first flow channel 1110 from the start end of the separation flow channel 1220 toward the microparticle inlet 1111, and the other end of the transition flow channel 1130 is connected to the end of the first flow channel 1110. The microparticles flow at the end of the first flow channel 1110 by only accommodating a row of microparticles, ensuring that only a single microparticle enters the corresponding valve switch mechanism at the end of the transition flow channel 1130 into a particular sorting flow channel 1220.

Referring to the second embodiment of the valve switching mechanism of fig. 1 to 2, the valve switching mechanism 2000 includes a pressure pump 2100 and a control fluid channel 2300, the control fluid channel 2300 being disposed inside the chip layer mechanism 1000, one end of the control fluid channel 2300 being in communication with the beginning of the sorting flow channel 1220, and a pressure port of the pressure pump 2100 being in communication with the other end of the control fluid channel 2300. An additional control flow channel 2300 is provided at the beginning of the plurality of sorted flow channels, the flow of which is modified by pressure pump control. When a particular microparticle passes through the microparticle focus region, the pressure pump controls the fluid flow rate to push the microparticle into a different sorting flow channel 1220.

The invention also discloses a particle flow sorting method, which comprises the following steps: the fine particle flow sorting apparatus described above.

Referring to fig. 8, the apparatus further includes a detection mechanism 3000 disposed at the end of the first flow channel 1110, in the figure, the detection mechanism is a microscope structure, and performs classification according to different visual attributes of the microparticles, and the microparticle sorting system mainly includes image acquisition, image recognition, data processing, hardware control, and a visual GUI interactive page based on Python development language. The method comprises the steps of rapidly capturing a screen (35 ms/frame) in a detection area to realize rapid image acquisition, converting the acquired image from an RGB space to an hsv space by using opencv, carrying out graying operation, carrying out color and size detection by Gaussian fuzzy denoising, expansion, corrosion, contour detection and contour drawing, judging whether microparticles of adjacent frames are the same microparticles or not by setting a time threshold, displaying a detection result on a GUI (graphical user interface) developed by PyQt5 in real time, and transmitting a corresponding instruction according to the detection result to control a pressure pump control valve switch structure so as to realize automatic microparticle sorting based on color or size. The time from the collection to the instruction sending of each frame of image is controlled to be about 40ms, the collection of the image does not need additional hardware support, the method is efficient and convenient, and the whole process from the focusing of the microparticles to the detection and sorting is fully automatic. Other detection equipment can be arranged at the position, and the detection equipment performs sorting according to the difference standard of the size of the micro-particles, fluorescence and electric signals.

S100, liquid and microparticles are introduced through the beginning of the microparticle focusing region 1100, and the microparticles flow through the first flow channel 1110 from the beginning to the end of the microparticle focusing region 1100.

S200, focusing the micro-particles from the first flow channel 1110 sequentially through the plurality of micro-holes 1121 arranged in at least one row along a straight line at the end of the micro-particle focusing region 1100.

S300, after the detecting mechanism 3000 identifies the attributes of the micro-particles, the valve opening/closing mechanism 2000 is controlled to be opened or closed to actively control the micro-particles with different attributes to flow into the corresponding sorting channels 1220, thereby completing the sorting of the micro-particles. The method focuses the sorted microparticles to include cells.

According to the micro-particle flow sorting device and method, a series of micro-particles avoid the use of an external physical field or sheath flow in a passive focusing mode, the complexity of chip manufacturing and specific operation is effectively simplified, and the micro-particles are not damaged.

The micro-particle flow focusing device has good focusing effect and can realize one-dimensional focusing on micro-particles.

The device of the invention requires a shorter channel length than inertial microfluidics, allowing a reduction in the size of the device. The device can realize the focusing of the particles without high flow velocity, can be applied to a plurality of scenes with low flow velocity, and can realize the accurate detection and sorting of single particles.

The microparticle sorting method can select different detection mechanisms for sorting based on the difference of the size, fluorescence and electric signals of the microparticles.

The present invention is not limited to the above embodiments, and any modifications, equivalent substitutions, improvements, etc. within the spirit and principle of the present disclosure should be included in the scope of the present disclosure as long as the technical effects of the present invention are achieved by the same means. Are intended to fall within the scope of the present invention. The invention is capable of other modifications and variations in its technical solution and/or its implementation, within the scope of protection of the invention.

Claims

1. A focusing device for focusing a flow of fine particles, comprising:

a chip layer mechanism (1000), a microparticle focusing region (1100) is arranged inside the chip layer mechanism (1000),

the micro particle focusing device comprises a micro particle focusing region (1100), wherein a first flow channel (1110) and at least one row of micro pore mechanisms (1120) corresponding to the lower part of the first flow channel (1110) are respectively arranged on the upper layer and the lower layer of the micro particle focusing region (1100), each micro pore mechanism (1120) comprises a plurality of micro pores (1121) which are arranged in rows, and a micro particle inlet (1111) is arranged at the starting end of the first flow channel (1110).

2. The microparticle flow focusing device according to claim 1, further comprising:

a micro-particle sorting region (1200), wherein the micro-particle sorting region (1200) comprises a plurality of sorting flow channels (1220), and the tail ends of the sorting flow channels are communicated with a sorting outlet (1221);

a valve opening/closing mechanism (2000) provided in the vicinity of each of the sorting flow paths (1220),

wherein the start of the sorting channel (1220) is in communication with the end of the first channel (1110).

3. The micro-particle flow focusing device of claim 2,

the micropore mechanism (1120) further comprises a second flow channel (1122), and the connected micropores (1121) are communicated through the second flow channel (1122).

4. The micro-particle flow focusing arrangement of claim 3,

the micropores (1121) are respectively mirror-symmetrical to the central axis of the first flow channel (1110).

5. The microparticle flow sorting device according to claim 2, wherein the first and second flow-dividing members are provided with a first and second flow-dividing member,

the plurality of adjacent second flow channels (1122) and the micropores (1121) are symmetrically arranged along a central axis of a flow direction, and the shape of the cross section of the micropore (1121) comprises one or more of a circle, an ellipse, a triangle, a rhombus or a convergent streamline shape.

6. The micro-particle flow focusing device of claim 1,

the valve switching mechanism (2000) comprises a pressure pump (2100) and a film layer (2200), wherein a plurality of air passages (2210) are arranged in the middle of the film layer (2200), an air inlet (2211) and an air outlet (2212) are respectively arranged at two ends of each air passage (2210), a high-pressure outlet (2110) and a low-pressure inlet (2120) of the pressure pump (2100) are respectively communicated with the air inlet (2211) and the air outlet (2212),

the thin film layer (2200) is bonded and connected on the surface of the chip layer mechanism (1000), each air channel (2210) correspondingly crosses over the starting end of the sorting flow channel (1220), the intersecting part of the bottom surface of the air channel (2210) and the sorting flow channel (1220) is a switch layer (2213), when high-pressure gas is introduced into the air channel (2210) from a high-pressure outlet (2110) of the pressure pump (2100), the switch layer (2213) is extruded by the high-pressure gas to expand towards the bottom surface of the sorting flow channel (1220), so that the switch layer (2213) blocks the sorting flow channel (1220), and when the high-pressure gas flows out from a gas outlet (2212) of the pressure pump (2100), the deformation of the switch layer (2213) is restored to dredge the sorting flow channel (1220).

7. The micro-particle flow focusing device of claim 1,

the microparticle focusing region (1100) further comprises a transition flow channel (1130),

one end of a transition flow channel (1130) is communicated with the first flow channel (1110) from the starting end of the sorting flow channel (1220) to the direction of the microparticle inlet (1111), and the other end of the transition flow channel (1130) is connected with the tail end of the first flow channel (1110).

8. The micro-particle flow focusing device of claim 1,

the valve switching mechanism (2000) comprises a pressure pump (2100) and a control fluid channel (2300), wherein the control fluid channel (2300) is arranged inside the chip layer mechanism (1000), one end of the control fluid channel (2300) is communicated with the initial end of the sorting flow channel (1220), and the pressure opening of the pressure pump (2100) is communicated with the other end of the control fluid channel (2300).

9. A method of micro-particle flow focusing and active sorting, the method of operating the device of any of claims 1 to 8, wherein the device comprises a detection mechanism (3000) disposed at the end of the first flow channel (1110), characterized in that the method comprises the steps of:

s100, introducing liquid and micro-particles through the initial end of the micro-particle focusing region (1100), wherein the micro-particles flow through a first flow channel (1110) from the initial end to the tail end of the micro-particle focusing region (1100);

s200, focusing the micro-particles on the tail end of a micro-particle focusing region (1100) along a straight line from the first flow channel (1110) through a plurality of micropores (1121) arranged in at least one row in sequence;

s300, after the detection mechanism (3000) identifies the attributes of the micro-particles, the opening or closing of the valve switch mechanism (2000) is controlled to actively control the micro-particles with different attributes to flow into the corresponding sorting flow channels (1220), and sorting of the micro-particles is completed.