CN214881401U

CN214881401U - Micro-fluidic flow channel and micro-fluidic chip

Info

Publication number: CN214881401U
Application number: CN202120261324.6U
Authority: CN
Inventors: 蒙玄; 杨家敏
Original assignee: Guangzhou Wondfo Biotech Co Ltd
Current assignee: Guangzhou Wondfo Biotech Co Ltd
Priority date: 2021-01-29
Filing date: 2021-01-29
Publication date: 2021-11-26
Anticipated expiration: 2031-01-29

Abstract

The utility model relates to a micro-fluidic runner and micro-fluidic chip, micro-fluidic runner include separation tube way, separation tube way is including the linking section that is connected and be responsible for the section, the one end that links up the section and keep away from and be used for being connected with the inlet pipe, be responsible for the section and keep away from the one end that links up the section and be used for being connected with outlet pipe, link up the width that the section is perpendicular on its extending direction and be less than be responsible for the width that the section is perpendicular on its extending direction. The sample gets into the linking section and the main pipe section of sorting pipe from the entry pipeline in proper order, and the width of sorting pipe often is more than the width of entry pipeline, is less than the linking section transition of being responsible for the section through setting up the width and is responsible for the section to be responsible for, plays the cushioning effect, avoids the sample to get into the broad runner by less runner suddenly, disturbs the motion trail of original particle, also avoids flowing through longer main pipe section and just can make the particle press close to the runner inner wall and gather into the thin area.

Description

Micro-fluidic flow channel and micro-fluidic chip

Technical Field

The utility model relates to a particle sorting technology field especially relates to a micro-fluidic runner and micro-fluidic chip.

Background

The inertial aggregation microfluidic technology is gradually applied to a cell sorting link in the biomedical industry, for example, circulating tumor cells are sorted from blood, a sample is led into a flow channel of a microfluidic chip in the sorting process, and different particles in the sample are separated by using a physical principle. The stability of the flow velocity of the sample in the microfluidic chip influences the particle aggregation effect, and the influence on the sorting result is large. In order to ensure stable particle flow state and realize inertial aggregation, a spiral channel or a linear arc-shaped channel is adopted in the traditional technology, but the spiral channel is difficult to manufacture and causes a micro-fluidic chip to have a larger size, while a general linear arc-shaped channel usually needs to be provided with a longer pipeline to stabilize particles and realize the inertial aggregation of the particles, thereby causing the micro-fluidic chip to have a larger size.

SUMMERY OF THE UTILITY MODEL

In view of the above, it is desirable to provide a microfluidic channel and a microfluidic chip, which are not only beneficial to the inertial aggregation of particles, but also capable of shortening the length of the channel.

The utility model provides a micro-fluidic flow channel, includes the sorting conduit, the sorting conduit is including linking section and the main pipe section that is connected, the one end that links up the section and keep away from the main pipe section is used for being connected with the inlet pipe, the one end that the main pipe section kept away from linking section is used for being connected with the export pipeline, link up the width that the section is perpendicular to its extending direction and be less than the width that the main pipe section is perpendicular to its extending direction.

During the separation, the sample gets into the linking section and the main pipe section of separation pipeline from the inlet pipe in proper order, the width of separation pipeline is often more than the width of inlet pipe, be less than the linking section transition of main pipe section to main pipe section through setting up the width, play the cushioning effect, avoid the sample to get into the broad runner by less runner suddenly, disturb the movement track of original particle, avoid destroying the original inertia gathering orbit of particle, and also avoid flowing through can make the particle press close to the runner inner wall and gather into the thin area behind the longer big width main pipe section, compare traditional linear arc runner, the length of main pipe section has been shortened, thereby can solve the unstable condition of the velocity of flow that the particle appears by different runner transitions through shorter runner, not only be favorable to the inertia gathering of particle, and can shorten runner length.

In one embodiment, the connecting section comprises a first elbow unit and a second elbow unit which are alternately arranged, and the radius of curvature of the first elbow unit is larger than that of the second elbow unit; the main pipe section comprises a third elbow unit and a fourth elbow unit which are alternately arranged, the curvature radius of the third elbow unit is larger than that of the fourth elbow unit, and the second elbow unit at the tail end is connected with the third elbow unit at the initial end; wherein the width of the first bent pipe unit perpendicular to the extending direction thereof is a, the width of the third bent pipe unit perpendicular to the extending direction thereof is b, and a < b.

In one embodiment, b is 0.4mm to 1.2mm greater than a; or b is 0.7mm-0.9mm larger than a.

In one embodiment, the first bent pipe unit includes a first side wall and a second side wall which are oppositely arranged, the first side wall and the second side wall are asymmetric curved surfaces, the second bent pipe unit includes a third side wall and a fourth side wall which are oppositely arranged, the third side wall and the fourth side wall are asymmetric curved surfaces, the third side wall is connected with the second side wall, and the fourth side wall is connected with the first side wall;

the third pipe bending unit comprises a fifth side wall and a sixth side wall which are oppositely arranged, the fifth side wall and the sixth side wall are asymmetric curved surfaces, the fourth pipe bending unit comprises a seventh side wall and an eighth side wall which are oppositely arranged, the seventh side wall and the eighth side wall are asymmetric curved surfaces, the fifth side wall is connected with the eighth side wall, and the sixth side wall is connected with the seventh side wall;

the first pipe bending unit and the second pipe bending unit are arranged in a protruding mode towards different directions, the third pipe bending unit and the fourth pipe bending unit are arranged in a protruding mode towards different directions, and the first pipe bending unit and the third pipe bending unit are arranged in a protruding mode towards the same direction.

In one embodiment, the radius of curvature of the first sidewall is smaller than the radius of curvature of the second sidewall, and the radius of curvature of the fifth sidewall is larger than the radius of curvature of the sixth sidewall.

In one embodiment, a radius of curvature of the third sidewall is smaller than a radius of curvature of the fourth sidewall, and a radius of curvature of the seventh sidewall is smaller than a radius of curvature of the eighth sidewall.

In one embodiment, the sorting conduit is a sinusoidal arc flow channel.

A microfluidic chip comprises a functional board, wherein the functional board is provided with any one of the microfluidic flow channels.

When the microfluidic chip is adopted for sorting, a sample sequentially enters the connecting section and the main pipe section of the sorting pipeline from the inlet pipeline, the width of the sorting pipeline is often larger than that of the inlet pipeline, the transition from the connecting section with the width smaller than that of the main pipe section to the main pipe section has the buffering function, prevents the sample from suddenly entering a wider flow passage from a smaller flow passage, disturbs the motion track of the original particles, avoids damaging the original inertia gathering track of the particles, but also avoids the situation that the particles are gathered into a thin belt by being close to the inner wall of the flow channel after flowing through a longer main pipe section with large width, shortens the length of the main pipe section compared with the traditional linear arc-shaped flow channel, therefore, the unstable flow velocity condition caused by the transition of the particles from different flow channels can be solved through the shorter flow channel, the inertial aggregation of the particles is facilitated, the length of the flow channel can be shortened, and the miniaturization of the microfluidic chip is facilitated.

In one embodiment, the microfluidic chip further includes an upper cover plate and a lower cover plate, the upper cover plate is connected to one side surface of the functional plate in an overlapping manner, the lower cover plate is connected to the other side surface of the functional plate in an overlapping manner, the functional plate is further provided with an inlet pipeline and an outlet pipeline, the upper cover plate is provided with a sample inlet communicated with the inlet pipeline, and the lower cover plate is provided with an outlet communicated with the outlet pipeline.

In one embodiment, the outlet pipeline includes a recovery pipeline and a waste liquid pipeline connected to different sides of the main pipeline section, the outlet includes a recovery hole communicated with the recovery pipeline and a waste liquid hole communicated with the waste liquid pipeline, and both the recovery pipeline and the waste liquid pipeline are in a reciprocating folding structure.

Drawings

FIG. 1 is a schematic diagram of an upper cover plate of a microfluidic chip according to an embodiment;

FIG. 2 is a schematic diagram of a first side of a functional plate of the microfluidic chip in one embodiment;

FIG. 3 is a schematic diagram of a second side of a functional board of the microfluidic chip according to an embodiment;

FIG. 4 is a schematic diagram of a lower cover plate of the microfluidic chip according to an embodiment;

FIG. 5 is a schematic diagram showing the movement state of circulating tumor cells, white blood cells and red blood cells in a blood sample in an inlet pipeline;

FIG. 6 is a schematic diagram showing the movement states of circulating tumor cells, white blood cells and red blood cells in a blood sample in a sorting pipeline.

Description of reference numerals:

01. red blood cells; 02. (ii) a leukocyte; 03. circulating tumor cells; 1. a function board; 10. an inlet duct; 11. a sample inlet hole; 110. a lead-in section; 112. a straight pipe section; 114. bending the pipe section; 120. a connecting section; 20. a sorting pipeline; 210. a joining section; 13. a first elbow unit; 13a, a first side wall; 13b, a second side wall; 14. a second elbow unit, 14a, a third side wall; 14b, a fourth side wall; 220. a main pipe section; 15. a third elbow unit; 15a, a fifth side wall; 15b, a sixth side wall, 16, a fourth elbow unit; 16a, a seventh side wall; 16b, an eighth sidewall; 30. deepening a flow channel; 40. a first turn flow path; 50. removing the flow channel; 51. a shunt hole; 52. a blocking member; 60. a second turning flow passage; 70. a recovery pipeline; 71. a first outflow aperture; 80. a waste liquid conduit; 81. a second outflow hole; 90. a buffer flow channel; 2. an upper cover plate; 21. a sample inlet; 3. a lower cover plate; 31. a recovery hole; 32. a waste liquid hole; 33. a discharge hole.

Detailed Description

In order to make the above objects, features and advantages of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, as those skilled in the art will be able to make similar modifications without departing from the spirit and scope of the present invention.

Referring to fig. 1 to 3, and fig. 1 to 4, an embodiment provides a microfluidic chip, including a functional board 1, where the functional board 1 is provided with an inlet pipeline 10, an outlet pipeline, and a microfluidic channel. Further, the microfluidic chip further comprises an upper cover plate 2 and a lower cover plate 3. The upper cover plate 2 is connected with a first side surface of the function plate 1 in an overlapping mode, the lower cover plate 3 is connected with a second side surface of the function plate 1 in an overlapping mode, and the upper cover plate 2 is provided with a sample inlet 21. And an outlet communicated with the outlet pipeline is formed in the lower cover plate 3.

Referring to fig. 2 and 5, in one embodiment, the microfluidic flow channel includes a sorting conduit 20, the sorting conduit 20 includes a connecting section 210 and a main conduit section 220 connected to each other, an end of the connecting section 210 away from the main conduit section 220 is used for connecting with the inlet conduit 10, an end of the main conduit section 220 away from the connecting section 210 is used for connecting with the outlet conduit, and a width of the connecting section 210 perpendicular to an extending direction thereof is smaller than a width of the main conduit section 220 perpendicular to the extending direction thereof.

During sorting, the sample gets into from inlet pipe 10 in proper order and sorts linking section 210 and main pipeline section 220 of pipeline 20, the width of sorting pipeline 20 often is more than inlet pipe 10's width, it is main pipeline section 220 to pass through linking section 210 that sets up the width and be less than main pipeline section 220, play the cushioning effect, avoid the sample to get into the broad runner suddenly by less runner, disturb the motion orbit of original particle, avoid destroying the original inertia gathering orbit of particle, and also avoid need flow through longer big width main pipeline section 220 after can make the particle press close to the runner inner wall and gather into the thin band, compare traditional linear arc runner, the length of main pipeline section 220 has been shortened, thereby can solve the unstable condition of velocity of flow that the particle appears by different runner transitions through shorter runner, be favorable to the inertia gathering of particle, and can shorten runner length. The microfluidic flow channel and the microfluidic core can be used for sorting and enriching the circulating tumor cells 03 in the blood sample and can also be used for sorting and enriching other biological particles.

Referring to fig. 2 and 5, in one embodiment, the inlet conduit 10 includes an introduction section 110 and a connection section 120 connected to each other, an end of the introduction section 110 away from the connection section 120 is communicated with the sample inlet 21, an end of the connection section 120 away from the introduction section 110 is communicated with the sorting conduit 20, and the introduction section 110 is in a reciprocating folded structure.

The introduction section 110 communicated with the sample inlet 21 is set to be a reciprocating folding structure, which achieves the purpose of buffering the liquid sample, so that the speed of the introduced sample in the introduction section 110 of the reciprocating folding structure gradually tends to be stable, and the introduction section 110 of the reciprocating folding structure can form a plurality of turns, due to the force influence of inertial lift force, dean drag force, etc., particles with smaller diameters such as red blood cells 01 flow disorderly and disorderly in the introduction section 110, while the particles with larger diameter such as leucocyte 02 and circulating tumor cells 03 are primarily gathered into a zone under the balance of the action force in the leading-in section 110 and then flow into the connecting section 120 to gradually form a thinner gathering zone, which is beneficial to the inertial gathering of the particles, and the processing difficulty is easier than that of a spiral pipeline or a traditional linear arc runner, and the overall runner layout is more concentrated due to the reciprocating inflection, so that the length of the runner can be effectively shortened.

Referring to fig. 5, when the blood sample enters the inlet end of the introduction section 110, red blood cells 01, white blood cells 02 and circulating tumor cells 03 are uniformly distributed in the flow channel. The diameter of the red blood cells 01 is about 6-8 μm, the diameter of the white blood cells 02 is about 8-12 μm, and the diameter of the circulating tumor cells 03 is about 20-30 μm. As the fluid flows through several turns of the introduction section 110, the white blood cells 02 and circulating tumor cells 03 slowly accumulate, while the red blood cells 01 are uniformly distributed. The bands of aggregated leukocytes 02 and circulating tumor cells 03 become thinner as they flow through the longer connecting segment 120, and become thinner and rest against the inner wall of the connecting segment 120 as the fluid flows into the fast-entry sorting channel 20. The introduction section 110 is set to be a reciprocating folding structure, which not only can play a role of buffering the inflow blood sample and make the liquid flow more stable, but also the blood sample flows through the introduction section 110 and the connection section 120, so that the circulating tumor cells 03 and the white blood cells 02 can be gathered in the flow channel.

The inlet duct 10 is an elongated flow channel compared to the sorting duct 20. Optionally, the inlet duct 10 has a width of 0.3mm to 1.2 mm. Preferably, the width of the inlet duct 10 is 0.5mm-0.9 mm. Optionally, the inlet duct 10 has a depth of 0.06mm-0.3 mm. Preferably, the inlet duct 10 has a depth of 0.1mm to 0.2 mm. So set up, make the blood sample velocity of flow that gets into inlet pipeline 10 tend to steadily, make circulating tumor cell 03 and leucocyte 02 can tentatively gather the area simultaneously, be convenient for follow-up sorting circulating tumor cell 03.

Specifically, referring to fig. 5, in an embodiment, the introduction section 110 includes a plurality of straight tube sections 112 and a plurality of bent tube sections 114, two adjacent straight tube sections 112 are connected by the bent tube sections 114, the straight tube section 112 at the initial end is communicated with the sample inlet 21 through the sample inlet 11, and the bent tube section 114 at the final end is disposed in a clockwise direction and connected to the connection section 120. So set up and make leading-in section 110 form a plurality of turnings, make blood sample speed tend to steadily gradually, play the cushioning effect, the preliminary gathering of leucocyte 02 and circulation tumor cell 03 of being convenient for, the processing degree of difficulty is also easier than the spiral pipeline, and the whole size of chip can be designed for littleer. The bending pipe section 114 at the extreme end of the introduction section 110 is connected with the connecting section 120 along the clockwise direction, and the main purpose is to enable the circulating tumor cells 03 with large particles to be always gathered at one side of the inner wall of the flow channel in the subsequent sorting process.

Referring to fig. 6, in one embodiment, the joint section 210 includes a first elbow unit 13 and a second elbow unit 14 alternately arranged, and the radius of curvature of the first elbow unit 13 is larger than that of the second elbow unit 14. The main tube section 220 comprises a third tube-bending unit 15 and a fourth tube-bending unit 16 which are alternately arranged, the radius of curvature of the third tube-bending unit 15 is larger than the radius of curvature of the fourth tube-bending unit 16, and the second tube-bending unit 14 at the end is connected with the third tube-bending unit 15 at the beginning. Wherein the width of the first bent-tube unit 13 perpendicular to its extending direction is a, the width of the third bent-tube unit 15 perpendicular to its extending direction is b, a < b. The connecting segment 210 is formed by alternately connecting a first elbow unit 13 having a large radius of curvature with a second elbow unit 14 having a small radius of curvature, and the main tube segment 220 is formed by alternately connecting a third elbow unit 15 having a large radius of curvature with a fourth elbow unit 16 having a small radius of curvature. The width of the connecting section 210 perpendicular to the extending direction thereof mainly refers to the width of the first elbow unit 13 perpendicular to the extending direction thereof, and the width of the main pipe section 220 perpendicular to the extending direction thereof mainly refers to the width of the third elbow unit 15 perpendicular to the extending direction thereof. According to the factors such as the diameter of the cells, the height and width of the flow channel, the flow speed of the liquid and the like, and the stress analysis of the inertial lift force, the dean drag force and the like, the circulating tumor cells 03 are close to the bottom of the inner wall of the main pipe section 220, and the white blood cells 02 are also gradually close to the bottom of the inner wall of the main pipe section 220. Alternatively, b is 0.4mm to 1.2mm greater than a. Preferably, b is 0.7mm to 0.9mm greater than a.

Referring to fig. 6, further, the first elbow unit 13 includes a first side wall 13a and a second side wall 13b disposed opposite to each other, and the first side wall 13a and the second side wall 13b are asymmetric curved surfaces. The second pipe bending unit 14 includes a third side wall 14a and a fourth side wall 14b disposed opposite to each other, and the third side wall 14a and the fourth side wall 14b are asymmetric curved surfaces. The third side wall 14a is connected to the second side wall 13b, and the fourth side wall 14b is connected to the first side wall 13 a. The third pipe bending unit 15 includes a fifth side wall 15a and a sixth side wall 15b that are disposed opposite to each other, and the fifth side wall 15a and the sixth side wall 15b are asymmetric curved surfaces. The fourth pipe bending unit 16 includes a seventh side wall 16a and an eighth side wall 16b disposed opposite to each other, and the seventh side wall 16a and the eighth side wall 16b are asymmetric curved surfaces. The fifth side wall 15a is connected to the eighth side wall 16b, and the sixth side wall 15b is connected to the seventh side wall 16 a. The first pipe bending unit 13 and the second pipe bending unit 14 are arranged to protrude in different directions, the third pipe bending unit 15 and the fourth pipe bending unit 16 are arranged to protrude in different directions, and the first pipe bending unit 13 and the third pipe bending unit 15 are arranged to protrude in the same direction. The asymmetric curved surface is arranged in such a way to form asymmetric inertial aggregation, so that the circulating tumor cells 03 are focused at a stable position (the bottom of the inner wall of the flow channel) in the cross section of the flow channel to form a zone, and the focused flow flows to the downstream.

Further, the radius of curvature of the first side wall 13a is smaller than that of the second side wall 13b, and the radius of curvature of the fifth side wall 15a is larger than that of the sixth side wall 15 b. So that the distance between the first side wall 13a and the second side wall 13b is smaller than the distance between the fifth side wall 15a and the sixth side wall 15b, and the buffer of the fluid from the joint section 210 to the main pipe section 220 is realized. Further, the radius of curvature of the third side wall 14a is smaller than the radius of curvature of the fourth side wall 14 b. The curvature radius of the seventh side wall 16a is smaller than that of the eighth side wall 16 b.

Further, referring to fig. 2, in one embodiment, the sorting conduit 20 further includes a first turning flow channel 40 and a removal flow channel 50. One end of the first turning flow channel 40 is connected with the main pipe section 220, the other end is communicated with the removing flow channel 50, and a diversion hole 51 penetrating through the wall surface of the removing flow channel 50 is arranged in the removing flow channel 50. Blood flows in the removing flow channel 50 and flows through the shunting holes 51, the circulating tumor cells 03 continuously move along the bottom of the inner wall of the removing flow channel 50, and because the white blood cells 02 and the red blood cells 01 are uniformly distributed in the pipeline, part of the white blood cells 02 and the red blood cells 01 flow out of the shunting holes 51, so that the subsequent recycling of the circulating tumor cells 03 is facilitated. Because the flow velocity of the liquid in the flow channel is relatively reduced along with the outflow of the liquid from the diversion hole 51, the movement track of the circulating tumor cell 03 is slightly changed and is easy to move towards the direction far away from the inner wall of the flow channel, the circulating tumor cell 03 is easy to approach the diversion hole 51, and the first turning flow channel 40 with large curvature radius is connected before the flow channel 50 is removed, so that the circulating tumor cell 03 flows through the first turning flow channel 40 with large curvature and then flows closely to the bottom of the inner wall of the flow channel, the circulating tumor cell 03 is prevented from flowing into the diversion hole 51, and the recovery rate of the circulating tumor cell 03 is improved.

Referring to fig. 2 and 3, further, in one embodiment, a buffer flow channel 90 in a reciprocating and folding structure is disposed on the second side surface of the function board 1, and the buffer flow channel 90 is communicated with the diversion hole 51. The buffer flow channel 90 is designed to be a reciprocating and folding structure, so that the liquid flowing out of the removal flow channel 50 is stable, and the phenomenon that the flow of the residual liquid in the removal flow channel 50 is disturbed by shaking to influence the recovery of the subsequent circulating tumor cells 03 is avoided.

Referring to fig. 2, in one embodiment, a blocking member 52 is disposed in the removing flow channel 50 corresponding to an inlet of the diversion hole 51. The width of the blocking member 52 in the extending direction of the removal flow path 50 is larger than the diameter of the branch flow hole 51. The circulating tumor cells 03 are protected from flowing into the diversion holes 51 by the barriers 52, and since the white blood cells 02 and the red blood cells 01 are distributed in the flow channels uniformly, the white blood cells 02 and the red blood cells 01 flow out of the diversion holes 51, vertically flow into the second side surface of the functional plate 1, and flow into the buffer flow channels 90.

Further, referring to fig. 2, in one embodiment, the sorting conduit 20 further includes a second turning flow channel 60 connected to the removal flow channel 50. The radius of curvature of the second turning flow path 60 is larger than that of the removal flow path 50. After the blood flows through the shunt hole 51, the contents of the white blood cells 02 and the red blood cells 01 are gradually reduced, and the flow rate is also gradually reduced. The second turning flow channel 60 with the curvature radius larger than that of the removal flow channel 50 is connected, so that the motion track of the circulating tumor cells 03 can be stabilized, and the subsequent recovery of the circulating tumor cells 03 is facilitated.

In one embodiment, the outlet pipes on the function board 1 include a recovery pipe 70 and a waste pipe 80 connected to different sides of the main pipe section 220. The outlet includes a recovery hole 31 communicating with the recovery pipe 70 and a waste hole 32 communicating with the waste pipe 80.

Specifically, referring to fig. 2, the recovery channel 70 communicates with one side of the second turn flow channel 60 near where the circulating tumor cells 03 are accumulated, and the waste channel 80 communicates with the other side of the second turn flow channel 60. The circulating tumor cells 03 closely contact the inner wall of the second turn flow channel 60 and flow into the recovery channel 70, and the white blood cells 02 and the red blood cells 01 flow into the waste liquid channel 80. In one embodiment, the waste liquid pipe 80 and the recovery pipe 70 are in a reciprocating and folding structure, so as to stabilize the liquid flowing state, and prevent the liquid from influencing the movement track of the circulating tumor cells 03 at the end of the second turning flow channel 60 in the process of subsequently falling from the waste liquid hole 32 and the recovery hole 31.

Referring to fig. 1 to 4, in one embodiment, the upper cover plate 2 is bonded to the first side surface of the function board 1, and the lower cover plate 3 is bonded to the second side surface of the function board 1, so that the flow channels of the first side surface and the second side surface of the function board 1 form a sealed channel. The upper cover plate 2 is provided with a sample inlet 21 communicated with the inlet pipeline 10 on the first side surface of the functional plate 1, so that a blood sample can be conveniently led into the microfluidic chip from the sample inlet 21. The lower cover plate 3 is provided with a recovery hole 31, a waste liquid hole 32 and a discharge hole 33, the diversion hole 51 is communicated with the discharge hole 33, part of the white blood cells 02 and the red blood cells 01 flow to the second side surface of the function plate 1 from the diversion hole 51 in the removal flow channel 50 and flow out of the microfluidic chip from the discharge hole 33 of the lower cover plate 3, the recovery pipeline 70 is communicated with the recovery hole 31 through a first outflow hole 71 penetrating through the first side surface and the second side surface of the function plate 1, the separated circulating tumor cells 03 flow out of the microfluidic chip from the recovery hole 31 of the lower cover plate 3, the waste liquid pipeline 80 is communicated with the waste liquid hole 32 through a second outflow hole 81 penetrating through the first side surface and the second side surface of the function plate 1, and the rest other liquid flows out of the microfluidic chip from the waste liquid hole 32 of the lower cover plate 3.

In one embodiment, the sorting conduit 20 is a sinusoidal arcuate flow path. When the fluid flows in the arc-shaped channel, the fluid flowing in a parabola shape has the maximum velocity in the middle of the channel. When passing through the channel turn, the fluid in the middle of the micro-channel is subjected to the largest centrifugal force due to the largest flow velocity, so that the fluid flows to the outer side wall of the arc-shaped channel. The fluid near the channel wall is at a minimum velocity and is subject to a minimum centrifugal force and is therefore squeezed by the intermediate high velocity fluid. In order to maintain mass conservation throughout the fluid, a pair of counter-rotating and symmetrical vortices are formed in a direction perpendicular to the fluid flow, respectively above and below the cross-section of the channel, thereby creating a secondary flow of dean vortices. Dean eddy currents produce a drag effect on the particles in the fluid, known as dean drag. In the curved channel, the flowing particles are subjected to both inertial lift and dean drag, and the relative magnitudes of these two forces determine the focused flow conditions of the particles flowing in the curved channel. In this embodiment, the circulating tumor cells 03 are focused to a band on the inner wall of the flow channel due to the inertial lift force and the dean drag force in the sorting channel 20.

Further, a deepened flow channel 30 is provided at one side of the sorting duct 20. Specifically, the deepened flow passage 30 extends from the main tube section 220 to the second turning flow passage 60. Due to the stress influence of inertial lift force, dean drag force and the like, referring to fig. 2, 5 and 6, the diameter of red blood cells 01 in a sample is small, the red blood cells flow disorderly and disorderly in the inlet pipeline 10, the diameters of white blood cells 02 and circulating tumor cells 03 are large, under the balance of the action force in the inlet pipeline 10, the red blood cells are preliminarily gathered to form a band and then flow into the sorting pipeline 20, referring to fig. 6, at this time, the circulating tumor cells 03 are just gathered to form a thin band and are close to the bottom of the inner wall of the main pipeline section 220, the white blood cells 02 are not gathered at the bottom of the inner wall of the flow channel, but the band where the white blood cells 02 and the circulating tumor cells 03 are gathered is close to each other, a deepened flow channel 30 is dug on one side of the sorting pipeline 20 far away from the circulating tumor cells 03, the deepened flow channel 30 is arranged along the extension direction of the sorting pipeline 20, the depth of the deepened flow channel 30 is greater than the depth of the sorting pipeline 20, so that the liquid flow state near the outer wall of the sorting pipeline 20 is disturbed, the inertial lift force and the dean drag force are changed, the original balance is destroyed, and therefore the leucocyte 02 can generate a disordered motion state, the leucocyte 02 is further uniformly distributed in the sorting pipeline 20, the phenomenon that the leucocyte 02 aggregate is overlapped with the circulating tumor cell 03 is avoided, the erythrocyte 01 is also uniformly distributed in the same way, the aggregate which does not interfere with the circulating tumor cell 03 is guaranteed, the leucocyte 02 is prevented from being gathered at the bottom of the inner wall of the sorting pipeline 20, the circulating tumor cell 03 and the leucocyte 02 are conveniently separated subsequently, and the recycling of the circulating tumor cell 03 is facilitated.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

In the present application, unless expressly stated or limited otherwise, the first feature may be directly on or directly under the second feature or indirectly via intermediate members. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. The micro-fluidic flow channel is characterized by comprising a separation pipeline, wherein the separation pipeline comprises a connection section and a main pipeline section which are connected, one end of the connection section, far away from the main pipeline section, is used for being connected with an inlet pipeline, one end of the main pipeline section, far away from the connection section, is used for being connected with an outlet pipeline, and the width of the connection section, perpendicular to the extending direction of the connection section, is smaller than the width of the main pipeline section, perpendicular to the extending direction of the connection section.

2. The microfluidic flow channel according to claim 1, wherein the connecting section comprises a first elbow unit and a second elbow unit alternately arranged, and a radius of curvature of the first elbow unit is larger than a radius of curvature of the second elbow unit; the main pipe section comprises a third elbow unit and a fourth elbow unit which are alternately arranged, the curvature radius of the third elbow unit is larger than that of the fourth elbow unit, and the second elbow unit at the tail end is connected with the third elbow unit at the initial end; wherein the width of the first bent pipe unit perpendicular to the extending direction thereof is a, the width of the third bent pipe unit perpendicular to the extending direction thereof is b, and a < b.

3. The microfluidic flow channel of claim 2, wherein b is 0.4mm to 1.2mm larger than a; or b is 0.7mm-0.9mm larger than a.

4. The microfluidic flow channel according to claim 2, wherein the first tube bending unit comprises a first sidewall and a second sidewall opposite to each other, the first sidewall and the second sidewall are asymmetric curved surfaces, the second tube bending unit comprises a third sidewall and a fourth sidewall opposite to each other, the third sidewall and the fourth sidewall are asymmetric curved surfaces, the third sidewall is connected to the second sidewall, and the fourth sidewall is connected to the first sidewall;

5. The microfluidic flow channel of claim 4, wherein the radius of curvature of the first sidewall is smaller than the radius of curvature of the second sidewall, and the radius of curvature of the fifth sidewall is larger than the radius of curvature of the sixth sidewall.

6. The microfluidic flow channel of claim 5, wherein the radius of curvature of the third sidewall is smaller than the radius of curvature of the fourth sidewall, and the radius of curvature of the seventh sidewall is smaller than the radius of curvature of the eighth sidewall.

7. The microfluidic flow channel of any of claims 1-6, wherein the sorting conduit is a sinusoidal arc flow channel.

8. A microfluidic chip, comprising a functional plate, wherein the functional plate is provided with the microfluidic flow channel according to any one of claims 1 to 7.

9. The microfluidic chip according to claim 8, further comprising an upper cover plate and a lower cover plate, wherein the upper cover plate is connected to one side of the functional plate in an overlapping manner, the lower cover plate is connected to the other side of the functional plate in an overlapping manner, the functional plate is further provided with an inlet pipeline and an outlet pipeline, the upper cover plate is provided with a sample inlet communicated with the inlet pipeline, and the lower cover plate is provided with an outlet communicated with the outlet pipeline.

10. The microfluidic chip according to claim 9, wherein the outlet conduit comprises a recovery conduit and a waste conduit connected to different sides of the main conduit, the outlet comprises a recovery hole communicated with the recovery conduit and a waste hole communicated with the waste conduit, and the recovery conduit and the waste conduit are both in a reciprocating folded structure.