CN-122006825-A - Microfluidic chip, microfluidic system and processing method

Abstract

The invention discloses a microfluidic chip, a microfluidic system and a treatment method, wherein the microfluidic chip comprises a first runner, a first buffer solution runner, a first waste liquid runner and a cleaning runner group, wherein the first buffer solution runner, the first waste liquid runner and the cleaning runner group are communicated with the first runner, the cleaning runner group comprises at least two cleaning runners which are sequentially arranged along the flowing direction, the diameter of an inlet of each cleaning runner is smaller than that of a first target object, and the microfluidic system further comprises a micro valve which is arranged corresponding to each runner. When the first micro valve and the first waste liquid micro valve are in an open state so that a single first target flows to the first area, the first micro valve and the first waste liquid micro valve are switched to a closed state, and the first buffer micro valve and the cleaning micro valve are in an open state so that a single first target flows to an inlet of one of the cleaning flow channels and stops at the inlet, and liquid in the first area flows out through other cleaning flow channels. The invention can screen out single first target objects from the first carrier liquid containing the first target object A and non-target objects.

Inventors

• CAO XIAOBAO
• XU WENHUA
• LIU YA
• HAN MENGYING
• LUO XINYI
• JIN JIAN
• XU TAO

Assignees

• 广州国家实验室

Dates

Publication Date

20260512

Application Date

20241112

Claims (20)

1. 1. The microfluidic chip is applied to screening of a first target object and is characterized by comprising a first runner, a first buffer runner, a first waste liquid runner and a cleaning runner group, wherein the first buffer runner, the first waste liquid runner and the cleaning runner group are respectively communicated with the first runner, the first runner is used for allowing liquid containing the first target object to flow through, the first waste liquid runner and the cleaning runner group are arranged at the downstream of the first buffer runner along the flow direction of the liquid in the first runner, the cleaning runner group comprises at least two cleaning runners which are sequentially arranged along the flow direction, and the diameter of an inlet of the cleaning runner is smaller than that of the first target object; The microfluidic system further comprises a first micro valve arranged corresponding to the first flow channel, a first buffer micro valve arranged corresponding to the first buffer flow channel, a first waste liquid micro valve arranged corresponding to the first waste liquid flow channel and cleaning micro valves arranged corresponding to the cleaning flow channels, wherein the first micro valve is used for controlling the on-off of the first flow channel, the first buffer micro valve is used for controlling the on-off of the first buffer flow channel, the first waste liquid micro valve is used for controlling the on-off of the first waste liquid flow channel, and the cleaning micro valve is used for controlling the on-off of the cleaning flow channels; The first flow channel between the first buffer flow channel and the cleaning flow channel group is defined as a first area, and the microfluidic chip is configured such that after the first micro valve and the first waste liquid micro valve are in an open state so that a single first target flows to the first area, the first micro valve and the first waste liquid micro valve are switched to a closed state, and the first buffer micro valve and the cleaning micro valve are in an open state so that the single first target flows to an inlet of one of the cleaning flow channels and stops at the inlet, and liquid in the first area flows out through the other cleaning flow channels.
2. 2. The microfluidic chip according to claim 1, wherein the first waste flow channel and the washing flow channel are independent flow channels, and the diameter of the first waste flow channel is larger than the diameter of the washing flow channel.
3. 3. The microfluidic chip according to claim 2, wherein the first buffer flow channel, the first waste flow channel and the washing flow channel group are sequentially arranged along the flow direction; The first flow channel between the first buffer flow channel and the first waste liquid flow channel is defined as a second area, when the first micro valve and the first waste liquid micro valve are in an open state and a single first target object flows to the first area, the first micro valve and the first waste liquid micro valve are switched to a closed state, and the first buffer micro valve and the cleaning micro valve are in an open state, including when the first micro valve and the first waste liquid micro valve are in an open state and a single first target object flows to the second area, the first micro valve and the first waste liquid micro valve are switched to a closed state, and the first buffer micro valve and the cleaning micro valve are switched to an open state.
4. 4. The microfluidic chip according to claim 1, wherein at least one of the cleaning flow channels is the first waste flow channel and the cleaning micro valve is the first waste micro valve.
5. 5. The microfluidic chip according to claim 1, wherein the washing flow channel comprises a first washing section communicating with the first flow channel, the first washing section having the inlet toward one end of the first flow channel, and a cross-sectional area of the first washing section gradually increasing from the one end having the inlet along a flow direction of the liquid in the washing flow channel.
6. 6. The microfluidic chip according to claim 4, wherein the washing flow channel further comprises a second washing section communicating with the first washing section along a flow direction of the liquid in the washing flow channel, and a cross-sectional area of the second washing section is greater than or equal to a maximum cross-sectional area of the first washing section.
7. 7. The microfluidic chip according to claim 1, wherein the diameter of the inlet of the first waste flow channel is 5 to 10 microns.
8. 8. The microfluidic chip according to claim 1, further comprising a connecting flow channel, wherein one end of the connecting flow channel is communicated with the first flow channel, the other end is communicated with each cleaning flow channel, and the length of the connecting flow channel is 3 micrometers to 8 micrometers along the flow direction of the liquid in the connecting flow channel.
9. 9. The microfluidic chip of claim 1, further comprising a second flow channel, an oil flow channel, a second buffer flow channel, and a mating flow channel, wherein the mating flow channel is connected to the oil flow channel, and wherein the first flow channel, the second flow channel, and the second buffer flow channel are all connected to the mating flow channel, and wherein the second flow channel is configured to flow a liquid containing a second target; The microfluidic chip further comprises a pairing micro valve corresponding to the pairing flow channel, a second micro valve corresponding to the second flow channel, an oil micro valve corresponding to the oil flow channel and a second buffer micro valve corresponding to the second buffer flow channel, wherein the pairing micro valve is used for controlling the on-off of the pairing flow channel, the second micro valve is used for controlling the on-off of the second flow channel, the oil micro valve is used for controlling the on-off of the oil flow channel, and the second buffer micro valve is used for controlling the on-off of the second buffer flow channel; When the single first target object from the first flow channel and the single second target object from the second flow channel exist in the pairing flow channel, the first micro valve, the second micro valve, the first buffer micro valve, the first waste liquid micro valve and the cleaning micro valve are all in a closed state, and the pairing micro valve and the second buffer micro valve are in an open state so as to send the single first target object and the single second target object in the pairing flow channel into oil in the oil flow channel to form liquid drops.
10. 10. The microfluidic chip of claim 9, wherein the microfluidic system further comprises a second waste flow channel and a second waste flow micro valve arranged corresponding to the second waste flow channel, the second waste flow channel is communicated with the pairing flow channel, the second waste flow micro valve is used for controlling on-off of the second waste flow channel, and the microfluidic chip is further configured such that when the single first object stops at the inlet of one of the cleaning flow channels, the first micro valve, the first waste flow micro valve, the cleaning micro valve, the second buffer flow channel and the pairing micro valve are all in a closed state, and the liquid in the first flow channel can flow out through the pairing flow channel and the second waste flow channel when the first buffer micro valve and the second waste flow channel are in an open state, so that the single first object enters the pairing flow channel from the first flow channel.
11. 11. The microfluidic chip of claim 10, wherein the microfluidic chip is further configured such that after the single first target is stopped at the inlet of one of the wash channels and the first buffer micro valve and the wash micro valve remain in an open state for a set time, the wash micro valve is switched to a closed state and the second waste micro valve is switched to an open state to allow the single first target to enter the mating channel from the first channel.
12. 12. The microfluidic chip according to claim 9, wherein the microfluidic system further comprises a second waste flow channel and a second waste micro valve arranged corresponding to the second waste flow channel, the second waste flow channel is communicated with the pairing flow channel, and the second waste micro valve is used for controlling on-off of the second waste flow channel; When the first micro valve, the first waste liquid micro valve, the cleaning micro valve and the pairing micro valve are all in a closed state, and the first buffer micro valve and the second waste liquid micro valve are in an open state, the liquid in the first flow channel can flow out through the pairing flow channel and the second waste liquid flow channel; and/or when the pairing micro valve is in a closed state and the second micro valve and the second waste liquid micro valve are in an open state, the liquid in the second flow channel can flow out through the pairing flow channel and the second waste liquid flow channel.
13. 13. The microfluidic system of claim 1, further comprising a second runner, an oil runner, and a mating runner, the mating runner being in communication with the oil runner, the first runner and the second runner both being in communication with the mating runner; The micro-fluidic system further comprises a pairing micro valve arranged corresponding to the pairing flow channel and a second micro valve arranged corresponding to the second flow channel, wherein the pairing micro valve is used for controlling the on-off of the pairing flow channel, and the second micro valve is used for controlling the on-off of the second flow channel; When the single first target object from the first flow channel and the single second target object from the second flow channel exist in the pairing flow channel, the first micro valve, the second micro valve, the first waste liquid micro valve and the cleaning micro valve are all in a closed state, and the pairing micro valve and the first buffer micro valve are in an open state, so that the buffer in the first buffer micro valve sends the single first target object and the single second target object in the pairing flow channel into the oil in the oil flow channel to form liquid drops.
14. 14. The microfluidic chip according to any one of claims 9 to 13, wherein the second target is a detection microsphere, the detection microsphere comprises a marker core and a magnetic coating layer coated on the marker core, wherein the marker core comprises a polymer core and a detection marker located on the surface of the polymer core, and a primer strand is bonded to the surface of the magnetic coating layer.
15. 15. The microfluidic chip according to claim 14, wherein the magnetic coating layer is modified with streptavidin, the primer strand is modified with biotin, and the primer strand is bound to the streptavidin on the surface of the magnetic coating layer through biotin.
16. 16. The microfluidic chip according to claim 14, wherein the number of primer strands bound to the surface of the magnetic coating layer is 5×10 7 ～2×10 8 .
17. 17. The microfluidic chip according to claim 14, wherein the polymer comprises a copolymer or homopolymer of at least one monomer of styrene, acrylic acid ester, and methacrylic acid ester.
18. 18. The microfluidic chip according to claim 14, wherein the magnetic coating layer comprises at least one of ferroferric oxide, ferric oxide, ferrite material.
19. 19. The microfluidic chip according to claim 14, wherein the detection label comprises a fluorescent detection label.
20. 20. The microfluidic chip according to claim 19, wherein the fluorescent detection marker comprises at least one of APC, coomassie brilliant blue, and chlorider blue.

Description

Microfluidic chip, microfluidic system and processing method Technical Field The invention relates to the technical field of single-cell sequencing, in particular to a microfluidic chip, a microfluidic system and a processing method. Background Circulating Tumor Cells (CTCs) are rare cancer cells that are commonly found in the circulatory system of cancer patients, and are commonly found in the blood or lymph fluid of the patient. The circulating tumor cells fall off from the primary tumor and enter the circulating system, and can be used as seeds to form secondary tumors. During this metastasis, strong heterogeneity is observed in circulating tumor cells. Phenotypic variation between circulating tumor cells and molecular characteristics indicates the presence of a specific subset of circulating tumor cells, and this variation may result in different metastatic potential. Analysis of CTCs in breast cancer patients at the single cell level may reveal internal heterogeneity of patient cancer-related gene expression, and may further reveal molecular pathways that are activated or altered during tumor and metastatic evolution, enabling researchers to obtain important information about metastatic mechanisms and genomic alterations, which would be helpful in drug resistance studies, enhanced cancer treatment, and cancer management. The number of circulating tumor cells in a sample is rare, and in the face of the low sample size single cell sequencing requirements, the valve-based development of single cell sequencing systems has the advantages of low cost and high RNA capture efficiency. At present, the commercialized single-cell sequencing technology based on liquid drops or micropores has higher single-cell capturing efficiency and cell flux, however, the sample has other cells such as red blood cells, white blood cells and the like besides circulating tumor cells, and the great pollution of the red blood cells and the white blood cells reduces the accuracy of single-cell gene sequencing and improves the sequencing cost. Disclosure of Invention The present invention aims to solve at least one of the technical problems existing in the prior art. Therefore, the invention provides the microfluidic chip which can reduce the pollution of non-target objects to target objects. The invention also provides a microfluidic system and a processing method. According to the microfluidic chip in the first embodiment of the present invention, the microfluidic chip is applied to screening of a first target object, and comprises a first flow channel, a first buffer flow channel, a first waste liquid flow channel and a cleaning flow channel group, wherein the first buffer flow channel, the first waste liquid flow channel and the cleaning flow channel group are respectively communicated to the first flow channel, the first flow channel is used for flowing a liquid containing the first target object, the first waste liquid flow channel and the cleaning flow channel group are both arranged at the downstream of the first buffer flow channel along the flow direction of the liquid in the first flow channel, the cleaning flow channel group comprises at least two cleaning flow channels which are sequentially arranged along the flow direction, and the diameter of the inlet of the cleaning flow channel is smaller than the diameter of the first target object; The microfluidic system further comprises a first micro valve arranged corresponding to the first flow channel, a first buffer micro valve arranged corresponding to the first buffer flow channel, a first waste liquid micro valve arranged corresponding to the first waste liquid flow channel and cleaning micro valves arranged corresponding to the cleaning flow channels, wherein the first micro valve is used for controlling the on-off of the first flow channel, the first buffer micro valve is used for controlling the on-off of the first buffer flow channel, the first waste liquid micro valve is used for controlling the on-off of the first waste liquid flow channel, and the cleaning micro valve is used for controlling the on-off of the cleaning flow channels; The first flow channel between the first buffer flow channel and the cleaning flow channel group is defined as a first area, and the microfluidic chip is configured such that after the first micro valve and the first waste liquid micro valve are in an open state so that a single first target flows to the first area, the first micro valve and the first waste liquid micro valve are switched to a closed state, and the first buffer micro valve and the cleaning micro valve are in an open state so that the single first target flows to an inlet of one of the cleaning flow channels and stops at the inlet, and liquid in the first area flows out through the other cleaning flow channels. The microfluidic system according to the embodiment of the invention has at least the following beneficial effects: according to the microfluidic chip, through