WO2021243882A1

WO2021243882A1 - Microfluidic chip and in-vitro detection apparatus

Info

Publication number: WO2021243882A1
Application number: PCT/CN2020/115469
Authority: WO
Inventors: 白孟斌; 冷杰; 苗再奎
Original assignee: 广州万孚生物技术股份有限公司
Priority date: 2020-06-04
Filing date: 2020-09-16
Publication date: 2021-12-09
Also published as: CN111774104A

Abstract

A microfluidic chip and an in-vitro detection apparatus. The microfluidic chip is provided with sample adding cavities, a separation cavity, a first waste liquid cavity, a first capillary flow channel, a cushioning cavity, and a quantitative cavity. There are a plurality of sample adding cavities, and at least one sample adding cavity is connected to the cushioning cavity by means of the separation cavity and the first capillary flow channel in sequence.

Description

Microfluidic chip and in vitro detection device

This application claims the priority of the Chinese patent application whose application date is June 4, 2020 and the application number is 202010501152.5. The entire content of this application is incorporated into this application by reference.

Technical field

This application relates to the field of in vitro detection, for example, to a microfluidic chip and an in vitro detection device.

Background technique

In Vitro Diagnosis (IVD) belongs to the medical and biological industry, which refers to taking blood, body fluids, tissues and other samples from the human body, and using in vitro testing reagents, instruments, etc. to test and verify the samples in order to prevent diseases , Diagnosis, treatment testing, later observation, health evaluation, genetic disease prediction, etc. In vitro diagnosis is divided into three categories: biochemical diagnosis, immunodiagnosis, and molecular diagnosis according to methodology, as well as point-of-care rapid diagnosis POCT differentiated from biochemical, immunological and molecular diagnosis. Dry chemical reaction is a type of biochemical diagnosis, which uses biochemical reagents to react with a specific substrate, and then quantitatively detects the concentration of the target through an instrument to calculate certain biochemical indicators of the human body. Biochemical diagnosis in related technologies needs to be tested on a large biochemical analyzer, which leads to problems such as high reagent consumption and insufficient flexibility; while the general dry-type biochemical POCT diagnosis method has low test throughput, generally only one time Test one or several samples, one or several items. Microfluidics technology (Microfluidics) can integrate basic operation units such as sample preparation, reaction, separation, and detection in the biological, chemical, and medical analysis process on the chip, automatically complete the entire analysis process, greatly improving the detection efficiency, and at the same time The advantages of miniaturization, automation, etc., have become more and more widely used in the field of POCT.

In the field of biochemical testing, Abaxis of the United States took the lead in the development of microfluidic chips for biochemical testing. Domestic companies such as Tianjin Micronanochip and Chengdu Smart have similar microfluidic chip development. The chips of related products generally only have one test process for sample processing, and different types of samples cannot be distinguished, which easily leads to unnecessary sample waste and the testing process is not flexible enough.

Summary of the invention

This application provides a microfluidic chip capable of distinguishing different samples and an in vitro detection device containing the microfluidic chip.

An embodiment provides a microfluidic chip having a sample addition cavity, a separation cavity, a first waste liquid cavity, a first capillary flow channel, a buffer cavity, and a quantitative cavity;

The sample adding cavity has a sample hole, the sample adding cavity has a plurality, each of the sample adding cavity is connected with the buffer cavity, and at least one of the sample adding cavity is passed through the buffer cavity in turn. The separation cavity and the first capillary flow channel are connected to the buffer cavity, the buffer cavity is connected to the quantitative cavity, and the separation cavity is also connected to the first waste liquid cavity;

The microfluidic chip has a center of rotation, the separation cavity is farther away from the center of rotation than the sample loading cavity connected to it, and the first waste liquid cavity is farther away from the separation cavity In the rotation center, the buffer cavity is farther away from the rotation center than the sample loading cavity connected to it, and the first capillary flow channel gradually approaches from the end connected to the separation cavity toward the center of rotation. The direction of the rotation center extends and bends and then extends in a direction away from the rotation center to be connected to the buffer cavity, and the bending position is closer to the rotation relative to the separation cavity and the buffer cavity Center, the quantitative cavity is farther away from the rotation center than the buffer cavity.

In one of the embodiments, the microfluidic chip further has a second capillary flow channel, and one end of the second capillary flow channel is connected to the quantitative cavity, and is approached after being connected to the quantitative cavity. The direction of the rotation center extends and bends and then extends in a direction away from the rotation center, so as to discharge the solution to be measured in the dosing cavity from the other end.

In one of the embodiments, the microfluidic chip further has a liquid permeation hole, and one end of the liquid permeation hole is on the side surface where the second capillary flow channel is located and is connected to the second capillary flow channel. One end for discharging the solution to be tested is connected, and the other end is opened on the other side surface of the microfluidic chip.

In one of the embodiments, the microfluidic chip further has a second waste liquid cavity, the second waste liquid cavity is connected to the separation cavity through an overflow channel, and the overflow channel Relative to the second waste liquid cavity and the separation cavity, it is closer to the rotation center.

In one of the embodiments, the microfluidic chip further has a liquid separation channel, the liquid separation channel is connected to the buffer cavity and extends from the connecting end around the rotation center to the other end thereof;

There are multiple quantitative cavities, and the multiple quantitative cavities are distributed around the center of rotation on the outer side of the liquid separation channel, and each of the quantitative cavities is connected to the liquid separation channel.

In one of the embodiments, the microfluidic chip further has a first penetration hole and a second penetration hole that penetrate the microfluidic chip;

The microfluidic chip has opposite sides of the surface, a first surface and a second surface, the buffer cavity and the liquid distribution channel are located on the first surface and the second surface, respectively. One end of the first penetration hole is connected to the buffer cavity on the first surface, and the other end is connected to the liquid distribution channel on the second surface;

The quantitative cavity is located on the first surface, one end of the second permeation hole is connected to the liquid distribution channel on the second surface, and the other end is on the first surface and corresponds to the quantitative cavity体连接。 Body connection.

In one of the embodiments, the microfluidic chip further has a third penetration hole and a quality control cavity, the quality control cavity is located on the first surface, and the third penetration hole penetrates the microfluidic In the chip, one end of the third penetration hole is connected to a position near the end of the liquid distribution channel on the second surface, and the other end is connected to the quality control cavity on the first surface.

In one of the embodiments, the microfluidic chip further has a fourth penetration hole and a third waste liquid cavity, the third waste liquid cavity is located on the first surface, and the fourth penetration hole penetrates the In the microfluidic chip, one end of the fourth penetration hole is connected to the tail end of the liquid separation channel on the second surface and the other end is connected to the third waste liquid cavity on the first surface .

In one of the embodiments, some cavities are directly provided with vents to exhaust air, and some cavities are exhausted through vents provided on other cavities connected to the cavities, and the vents are relative to the cavity directly connected to it. The body is closer to the center of rotation.

In one of the embodiments, two interconnected cavities or interconnected cavities and holes are connected by a micro channel.

In one of the embodiments, the sample loading cavity is arranged around the center of rotation; and/or

The size of the sample application cavity gradually increases from one end of the sample application to the other end thereof.

In one of the embodiments, the microfluidic chip is also provided with positioning holes.

An embodiment provides an in vitro detection device, including the microfluidic chip and a detection mechanism described in any of the above embodiments, the detection mechanism is in communication with the quantitative cavity, and the detection mechanism is used to detect the quantitative cavity Samples from the body.

In one of the embodiments, the detection mechanism is a dry chemical test paper.

In one of the embodiments, the dry chemical test paper includes a support layer and a reaction indicator layer and a diffusion layer sequentially stacked on the support layer, and the reaction indicator layer contains a substance capable of reacting with the target substance in the sample to be tested. Reaction reagents and indicator reagents, and the diffusion layer faces the quantitative cavity through its sample inlet.

In one of the embodiments, the microfluidic chip is provided with mounting grooves surrounding each of the quantitative cavities, and the detection mechanism is embedded in each of the mounting grooves to communicate with the quantitative cavity.

The microfluidic chip has a sample loading cavity, a separation cavity, a first waste liquid cavity, a first capillary flow channel, a buffer cavity, and a quantitative cavity. There are multiple sample loading cavities, and at least one The sample cavity is sequentially connected to the buffer cavity via the separation cavity and the first capillary flow channel. Therefore, when adding samples, different sample addition cavities can be selected according to the type of sample solution added, for example, when a whole blood sample is required. When testing, it can be added to the sample chamber connected to the separation chamber. Subsequent centrifugation can achieve the separation of blood cells from serum (or plasma) in the whole blood sample solution. Blood cells and other impurities can be Centrifugally deposited in the first waste liquid chamber, while the serum remains in the separation chamber; and when the serum sample needs to be tested, it can be directly added to the sample chamber connected to the buffer chamber , Without centrifugal separation, the subsequent quantification and detection process can be carried out directly. The microfluidic chip can differentiate and process different samples, is flexible and convenient to use, is beneficial to rational use according to the properties of the sample solution, is beneficial to reduce the waste of the sample solution, and saves the amount of sample used.

Description of the drawings

Fig. 1, Fig. 2 and Fig. 3 are schematic diagrams of the front, back, and side structures of a microfluidic chip according to an embodiment of the application, respectively.

Figure 4 is a schematic diagram of the structure of a dry chemical test strip.

5A to 5N are schematic diagrams of the separation, quantification and detection process of the whole blood sample solution realized by the microfluidic chip.

Figure 6 is a schematic diagram of the microfluidic chip for adding samples to serum samples.

The reference signs are explained as follows:

10: microfluidic chip, 101: center of rotation, 102: first surface, 103: second surface, 104: chip body, 105: cover film;

11: Sampling cavity, 110: Sampling hole, 111: First sampling cavity, 112: Second sampling cavity; 12: Separation cavity; 13: First waste liquid cavity; 14: First Capillary flow channels, 14a, 14b and 14c are the front section, bending apex and back section of the first capillary flow channel respectively; 15: buffer cavity; 16: quantitative cavity; 17: second capillary flow channel, 17a, 17b and 17c are the front section, the bending apex and the back section of the second capillary channel respectively; 18: liquid permeation hole; 19: second liquid waste cavity, 191: overflow channel; 20: branch flow channel; 21: No. One penetration hole; 22: second penetration hole; 23: third penetration hole; 24: quality control cavity; 25: fourth penetration hole; 26: third waste liquid cavity; 27: ventilation hole; 28: micro flow Road; 29: positioning hole; 30: mounting groove;

40: dry chemical test paper, 41: support layer, 42: reaction indicator layer, 43: diffusion layer.

detailed description

It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to another element or there may be a centering element at the same time, such as connection through a microfluidic channel.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field of this application. The terminology used in the specification of the application herein is only for the purpose of describing specific embodiments, and is not intended to limit the application. The term "and/or" as used herein includes any and all combinations of one or more related listed items.

1 and 2, an embodiment of the present application provides a microfluidic chip 10, which has a sample addition cavity 11, a separation cavity 12, a first waste liquid cavity 13, and a first capillary flow channel 14. , Buffer cavity 15 and quantitative cavity 16. The sample loading cavity 11 has a sample loading hole 110. In this embodiment, there are multiple sample loading cavities 11, and each sample loading cavity 11 is connected to the buffer cavity 15, and at least one of the sample loading cavities 11 passes through the separation cavity 12 and the first capillary flow channel in sequence. 14 is connected to the buffer cavity 15. The buffer cavity 15 is connected to the quantitative cavity 16. The separation cavity 12 is also connected to the first waste liquid cavity 13.

The middle part of the microfluidic chip 10 is a rotary mounting part, which has a rotation center 101, which is the center of rotation during centrifugal operation. The separation cavity 12 is farther away from the rotation center 101 than the sample addition cavity 11 connected to it, the first waste liquid cavity 13 is further away from the rotation center 101 relative to the separation cavity 12, and the buffer cavity 15 is relatively far from the sample addition cavity 11 connected to it. The cavity 11 is further away from the rotation center 101, and the first capillary channel 14 gradually approaches the rotation center 101 from the end connected to the separation cavity 12 (may be each gradually approaching the rotation center 101, for example, but not limited to It extends and bends in a direction away from the rotation center 101 (which may be a direction gradually away from the rotation center 101, for example, but is not limited to a radial direction away from the rotation center 101), and then extends to buffer The cavity 15 is connected and the bending position is closer to the rotation center 101 than the separation cavity 12 and the buffer cavity 15, and the quantitative cavity 16 is farther from the rotation center 101 than the buffer cavity 15.

For example, in the specific example shown in the figure, there are two sample adding cavities 11, namely, a first sample adding cavity 111 and a second sample adding cavity 112. Wherein, the first sample adding cavity 111 is connected to the buffer cavity 15 through the separation cavity 12 and the first capillary flow channel 14, and the second sample adding cavity 112 is directly connected to the buffer cavity 15. The direct connection described herein refers to that the two objects connected are not connected via other cavities, but are not limited to structures such as micro-channels and capillary channels for communication between the two objects.

Illustratively, in the specific example shown in the figure, the first sample application cavity 111 and the second sample application cavity 112 are both arranged around the rotation center 101. The first sample adding cavity 111 is used to add sample solutions such as whole blood. It has a large volume and is close to each other around the center of rotation 101. The sample solution added in it needs to be centrifuged; the second sample adding cavity 112 is used to add The volume of sample solutions such as serum or plasma is relatively small, and there is no need to centrifuge the added sample solution. Optionally, the size of the sample application cavity 11 gradually increases from one end of the sample application to the other end thereof, which facilitates the flow of the sample solution in the cavity and allows the sample solution to flow smoothly from one end to the other end to facilitate sample application. The "surround" mentioned herein can be a closed ring or not, for example, it can be surrounded by a fan with an angle greater than 180° or a fan with an angle of about 90°, etc., according to the needs of the sample amount, the center of the fan-shaped circle The angle of the angle is not limited.

In the specific example shown in the figure, the microfluidic chip 10 further has a second capillary flow channel 17. One end of the second capillary flow channel 17 is connected to the quantitative cavity 16, and after being connected to the quantitative cavity 16, it extends in a direction close to the rotation center 101 and is bent and then extends in a direction away from the rotation center 101, so as to extend the quantitative cavity The solution to be tested in 16 is discharged from the other end.

Optionally, in the specific example shown in the figure, the microfluidic chip 10 further has a liquid permeation hole 18. One end of the liquid permeation hole 18 is connected to one end of the second capillary flow channel 17 for discharging the solution to be tested on the side surface where the second capillary flow channel 17 is located, and the other end is open to the other end of the microfluidic chip 10 The side surface is used to export the sample solution to be tested, for example, to a test strip or other testing mechanism.

In the specific example shown in the figure, the microfluidic chip 10 also has a second waste liquid cavity 19. The second waste liquid cavity 19 is connected to the separation cavity 12 through an overflow channel 191. The overflow channel 191 is closer to the rotation center 101 relative to the second waste liquid cavity 19 and the separation cavity 12. When the separation cavity 12 and the first waste liquid cavity 13 are filled with liquid, the excess liquid enters the second waste liquid cavity 19 through the liquid flow channel 191. In the example shown in the figure, the second waste liquid cavity 19 has an elongated shape as a whole, one end is close to the rotation center 101 and the other end is far away from the rotation center 101.

In the specific example shown in the figure, the microfluidic chip 10 further has a liquid separation channel 20. The liquid distribution channel 20 is connected to the buffer cavity 15 and extends from the connecting end around the rotation center 101 to the other end thereof. Optionally, there are multiple quantitative cavities 16, the multiple quantitative cavities 16 are distributed around the rotation center 101 outside the liquid distribution channel 20, and each quantitative cavity 16 is connected to the liquid distribution channel 20.

In the specific example shown in the figure, each quantitative cavity 16, the second capillary flow channel 17, and the liquid permeation hole 18 constitute a certain amount of detection unit, so the microfluidic chip 10 has a plurality of quantitative detection units around its rotation center 101 . By setting multiple quantitative detection units, multiple quantifications of the sample solution can be achieved, which can be used to perform multiple repeated detections on the same index of the same sample to ensure the accuracy of the test results, or for multiple different indexes of the same sample Perform testing to fully reflect the various indicators of the sample solution. The microfluidic chip 10 with multiple quantitative detection units has a high degree of integration, which can significantly increase the single detection throughput.

As shown in FIGS. 1 and 2, the illustrated microfluidic chip 10 further has a first penetration hole 21 and a second penetration hole 22 penetrating the microfluidic chip 10. The microfluidic chip 10 has two opposite surfaces, a first surface 102 and a second surface 103, respectively. The buffer cavity 15 and the liquid distribution channel 20 are respectively located on the first surface 102 and the second surface 103. One end of the first penetration hole 21 is connected to the buffer cavity 15 on the first surface 102, and the other end is connected to the liquid distribution channel 20 on the second surface 103. The quantitative cavity 16 is located on the first surface 102. There are multiple second penetration holes 22. One end of the multiple second penetration holes 22 is connected to the liquid distribution channel 20 on the second surface 103, and the other end is on the first surface 102 and corresponds to The quantitative chamber 16 is connected.

By arranging the liquid separation channel 20 on the other surface of the microfluidic chip 10, the integration degree of the microfluidic chip 10 can be improved within a certain size range, which is beneficial to reduce the size of the microfluidic chip 10, and is beneficial to the product Miniaturized and portable design.

In the specific example shown in the figure, the microfluidic chip 10 further has a third penetration hole 23 and a quality control cavity 24. The quality control cavity 24 is located on the first surface 102, the third penetration hole 23 penetrates the microfluidic chip 10, one end of the third penetration hole 23 is connected to the position near the end of the liquid distribution channel 20 on the second surface 103 and the other end The first surface 102 is connected to the quality control cavity 24. By setting the quality control cavity 24, it is possible to determine whether each quantification cavity 16 is full of liquid by observing whether there is liquid in the quality control cavity 24, so that the sample solution can be accurately quantified, and part of the quantification cavity 16 can be avoided. The problem occurs that the detection volume of each quantitative detection unit is inconsistent because the sample solution is not filled with the sample solution, which affects the accuracy and reliability of the detection result.

In the specific example shown in the figure, the microfluidic chip 10 further has a fourth penetration hole 25 and a third waste liquid cavity 26. The third waste liquid cavity 26 is located on the first surface 102, the fourth permeation hole 25 penetrates the microfluidic chip 10, one end of the fourth permeation hole 25 is connected to the tail end of the liquid distribution channel 20 on the second surface 103 and the other end The first surface 102 is connected to the third waste liquid cavity 26. Optionally, in the example shown in the figure, the third waste liquid cavity 26 is arranged around the center of rotation 101 on the outside of each quantitative detection unit, and the third waste liquid cavity 26 is relatively large in size so that sufficient The volume accommodates the excess sample solution to be tested, so that a little more sample solution can be added when sample is added to prevent the problem that part of the quantitative cavity 16 is not full of the sample solution to be tested due to insufficient sample solution.

In the specific example shown in the figure, some cavities are directly provided with vents 27 for exhaust, and some cavities are exhausted through vents 27 provided on other cavities connected to the cavities. Each vent 27 is directly opposite to the vent 27 The connected cavity is closer to the center of rotation 101. For example, both the first sample adding cavity 111 and the second sample adding cavity 112 are provided with a vent 27, and optionally, they share one vent 27; for another example, each of the quantitative cavities 16, the second waste liquid cavity The body 19, the quality control cavity 24, and the third waste liquid cavity 26 are all independently provided with a vent 27.

In the specific example shown in the figure, the two cavities connected to each other or the cavities and the holes connected to each other are connected by a micro channel 28. For example, between the first sample addition cavity 111 and the separation cavity 12, between the separation cavity 12 and the first waste liquid cavity 13, and between each cavity and the corresponding vent 27 all pass through the micro flow channel 28 connect.

The capillary flow channel described herein (such as the first capillary flow channel 14 and the second capillary flow channel 17) is a flow channel structure having a smaller size (e.g., width and/or depth) than the micro flow channel 28. In a specific example, the main part of each capillary channel is in a V shape, and the bent part thereof is close to the rotation center 101. Optionally, the width of each capillary flow channel is 0.1mm-0.2mm and the depth is 0.1mm-0.2mm; or the width of each capillary flow channel is 0.2mm-0.5mm and the depth is 0.2mm-0.5mm. When the width of each capillary channel is 0.1mm-0.2mm and the depth is 0.1mm-0.2mm, no surface treatment is required. When the width of each capillary channel is 0.2mm-0.5mm and the depth is 0.2mm-0.5mm, The flow channel wall of each capillary flow channel can be surface treated with inert materials such as PEG4000. Optionally, the width of each capillary flow channel is 0.2 mm, and the depth is also 0.2 mm. After each capillary flow channel enters the sample solution, the sample solution can flow to the other end of the sample solution by capillary action. Optionally, each capillary channel has different sizes in different sections. For example, the width at the bending part is 0.2mm and the depth is also 0.2mm, and the width at other parts is 0.5mm and the depth is also 0.2mm, so as to facilitate Liquid flows and forms siphon and capillary action locally.

The PEG4000 surface treatment can be, but is not limited to, adding a 1wt% PEG4000 solution to the capillary flow channel and forming it after natural drying. The surface treatment of PEG4000 is beneficial to increase the capillary force of the capillary flow channel, and PEG4000 is an inert substance in the reaction system, and generally does not react with samples and test reagents, so it will not affect the test results.

The distance between the bent apex position of each capillary channel and the center of rotation 101 is less than the distance between the whole cavity directly connected to the center of rotation 101, so that during centrifugation, the sample solution flows with the capillary channel, but the centrifugal force is greater than With gross suction, the sample solution will not flow to the bending apex of the capillary channel. Therefore, the capillary channel can act as a valve during centrifugal separation of the sample solution to achieve a closed effect when the sample solution is quantified and detected.

By designing the microfluidic chip 10 with the above structure, the sample solution can be separated and quantified by one centrifugation, and the operation is simple, which is beneficial to improve the efficiency of separation and quantification of the sample solution.

Optionally, the microfluidic chip 10 also has positioning holes 29. By designing the positioning hole 29, it is convenient for the matching detection equipment to identify the position of the microfluidic chip 10, so as to determine the relative position of the detection mechanism installed on the microfluidic chip 10, such as dry chemical test paper, on the chip 10, thereby determining a detection mechanism Corresponding test items to complete the test to obtain the corresponding results.

In a specific example, as shown in FIG. 3, the microfluidic chip 10 includes a chip body 104 and a cover film 105 covering both sides of the chip body 104.

Sampling cavity 11, separation cavity 12, first waste liquid cavity 13, first capillary flow channel 14, buffer cavity 15, quantitative cavity 16, second capillary flow channel 17, and second waste liquid cavity 19 , The liquid flow channel 191, the liquid distribution channel 20, the quality control cavity 24, the third waste liquid cavity 26 and the micro channel 28 for connecting the cavities are all located on the same side surface of the chip body 104, for example On the first surface 102, the vent 27 is opened on the cover film 105 on this side, and the liquid distribution channel 20 is located on the other side surface of the chip body 104, for example, on the second surface 103.

The chip body 104 cooperates with the cover films 105 on both sides to form the structure of each cavity and flow channel (micro flow channel, capillary flow channel, etc.) of the microfluidic chip 10. Optionally, the grooves of each cavity and flow channel structure are pre-formed on the chip body 104, and subsequently covered by the cover film 12 and sealed on the front surface of the chip body 104 to complete the cavity and flow channel structure. Encapsulation to form a complete cavity and flow channel structure.

The material of the chip body 104 can be selected but not limited to monocrystalline silicon wafers, quartz, glass or high molecular organic polymer materials, such as polymethylmethacrylate (PMMA), polydimethylsiloxane (PDMS), polycarbonate Ester (PC) or hydrogel, etc. The entire chip body 104 can be selected as a disc shape, which is convenient for installation and ensures the stability of the centrifugal process.

The cover film 105 can be made of the same material as the chip body 104, in addition, it can also be an adhesive tape, such as pressure sensitive tape, double-sided tape or die-cut tape, etc., which cooperates with the chip body 104 to form the entire microfluidic chip 10. Simple assembly, no need to use complicated and expensive ultrasonic welding technology, just direct bonding, which can significantly reduce the production cost. In other specific examples, the microfluidic chip 10 may also be formed by welding with a relatively high-cost ultrasonic welding technology, or be integrally formed with a 3D printing technology.

The present application also provides an in vitro detection device, which includes the microfluidic chip 10 in any of the above specific examples and a detection mechanism, and the detection mechanism is used to detect a sample in the quantitative cavity 16.

In a specific example, the detection mechanism is a dry chemical test paper. The detection mechanism is in communication with the quantitative cavity 16.

Illustratively, as shown in FIG. 4, the dry chemical test paper 40 may include a supporting layer 41 and a reaction indicating layer 42 and a diffusion layer 43 stacked on the supporting layer 41 in sequence. The reaction indicator layer 42 contains reaction reagents and indicator reagents capable of reacting with the target substance in the sample to be tested. The diffusion layer 43 communicates with the quantitative cavity 16 through the sample inlet, for example, but is not limited to permeation through the sample inlet and the outlet liquid. The hole 18 communicates. The reaction reagent and the indicator reagent in the reaction indicator layer 42 may be located in the same layer, or may be located in different sublayers. It can be understood that in other specific examples, the detection mechanism is not limited to dry chemical test strips, and can also be various other test strips or reactors.

In a specific example, the microfluidic chip 10 is provided with a mounting groove 30 around each quantitative detection unit. A detection mechanism such as dry chemical test paper 40 may be embedded in each installation slot 30.

The microfluidic chip 10 has a sample loading cavity 11, a separation cavity 12, a first waste liquid cavity 13, a first capillary flow channel 14, a buffer cavity 15 and a quantitative cavity 16, wherein the sample loading cavity 11 has There are multiple, and at least one sample adding cavity 11 is connected to the buffer cavity 15 via the separation cavity 12 and the first capillary channel 14 in turn. Therefore, when adding samples, you can choose different types according to the type of sample solution added. The sample addition cavity 11, for example, when a whole blood sample needs to be tested, it can be added to the sample addition cavity 11 connected to the separation cavity 12, and subsequently under centrifugation, the whole blood sample solution can be added Separation of blood cells and serum (or plasma), blood cells and other impurities can be centrifuged and deposited in the first waste liquid cavity 13, while the serum remains in the separation cavity 12; another example is when serum samples need to be tested. It can be directly added to the sample loading cavity 11 connected to the buffer cavity 15, and the subsequent quantification and detection process can be directly performed without centrifugal separation. The microfluidic chip 10 can differentiate and process different samples, is flexible and convenient to use, is beneficial to rational use according to the properties of the sample solution, is beneficial to reduce the waste of the sample solution, and saves the amount of sample used.

Exemplarily, taking the microfluidic chip 10 shown in FIG. 1 and FIG. 2 as an example, the detection of a whole blood sample and a pure serum (or plasma) sample can be performed according to, but not limited to, the following operations.

For whole blood samples, the entire testing process includes three stages: separation, quantification and detection. Separation refers to the process of separating serum and blood cells by high-speed centrifugation. Quantification is the quantification of the required amount of serum for testing in each quantification chamber 16, and detection is to export the serum obtained in the quantification process to the testing organization. To be tested in. The whole process can be referred to as follows:

As shown in FIG. 5A, a whole blood sample is first added to the first sample adding cavity 111, and the excess air in the first sample adding cavity 111 is discharged through the corresponding vent 27;

After adding the complete blood sample, install the microfluidic chip 10 into the device with centrifugation function, start high-speed centrifugation, and control the rotation speed, for example, between 3000-6000 rpm. As shown in FIG. 5B, the whole blood sample flows into the separation chamber 12 And in the first waste liquid chamber 13, the excess whole blood sample flows into the second waste liquid chamber 19 through the liquid flow channel 191, and the excess air in the chamber passes through the vent hole provided on the second waste liquid chamber 19. 27 discharge.

Continue centrifugation, as shown in Figure 5C. Under the action of centrifugal force, the serum and blood cells in the whole blood sample are separated. Under the action of centrifugal force, the blood cells will all gather in the first waste liquid cavity 13, while the serum remains in the separation cavity. At the same time, part of the serum will enter the first capillary channel 14 connected to the separation cavity 12, as shown in Figure 5D, because the centrifugal force is greater than the capillary force in the first capillary channel 14, enter the first capillary channel 14 The serum in a capillary channel 14 stops flowing when it reaches the highest point of the separation cavity 12 and stays in the front section 14a. The first capillary channel 14 is closer to the bending apex of the rotation center 101 than the separation cavity. The body 12 as a whole is closer to the center of rotation, so the serum will not cross the bending apex 14b, and will not enter the rear section 14c. The first capillary flow channel 14 functions as a valve when the whole blood sample is centrifuged.

As shown in Figure 5E, Figure 5F and Figure 5G, when the centrifugation of the whole blood sample is completed, the centrifugation is stopped. At this time, the serum in the first capillary flow channel 14 will follow the first capillary flow channel 14 under the action of capillary force. The internal flow of the blood, and finally cross the bending apex 14b from the rear section 14c into the buffer cavity 15, and then continue to open the centrifugation, the separated serum sample enters the first permeation hole 21 through the buffer cavity 15 and enters the liquid separation channel 20 , The liquid is separated through the liquid separation channel 20, and the serum is guided into each quantitative cavity 16 through the second permeation hole 22.

As shown in FIG. 5H and FIG. 5I, when each quantitative cavity 16 is filled with serum samples, the excess serum samples enter the quality control cavity 24 through the third penetration hole 23, and the quality control cavity 24 can be detected by a testing instrument. Status, check whether there is serum in it. When there is serum in the quality control cavity 24, it means that each quantification cavity 16 is filled with serum. Subsequent testing can be performed normally. When there is no serum in the quality control cavity 24, it means There may be a case where part of the quantitative cavity 16 is not filled. At this time, the test instrument can give a reminder that a quality inspection is required. The quality control cavity 24 can also be equipped with corresponding reagents, which can be prompted by observing the color change of the quality control cavity 24 Whether there is liquid entering the quality control chamber.

As shown in FIG. 5J, when the quality control cavity 24 is also filled with liquid, the excess liquid will enter the third waste liquid cavity 26 and be collected.

During this period, as shown in FIG. 5K, liquid will also enter the second capillary flow channel 17 connected to each quantitative cavity 16. Since the centrifugal force is greater than the capillary force, the liquid entering the second capillary flow channel 17 will also stop and be quantitatively determined. The position where the cavity 16 is flush, that is, in the front section 17a, since the bending apex 17b is closer to the center of rotation than the entire quantitative cavity 16, the liquid will not cross the bending apex 17b, and will not enter the rear section 17c. The second capillary channel 17 functions as a valve during centrifugation. During high-speed centrifugation, the valve is closed, effectively keeping the liquid in each quantitative cavity 16 and controlling the smooth progress of the entire quantitative process.

When the quantification process is over, stop the centrifugation, as shown in Figure 5L and Figure 5M. At this time, the liquid in the second capillary channel 17 will flow along the second capillary channel 17 under the action of capillary force and finally pass over The bent apex 17b enters the rear section 17c. At this time, as shown in Fig. 5N, the low-speed centrifugation can be turned on, for example, it can be rotated at 1000-2500 rpm to promote the liquid from the rear section 17c through the liquid penetration hole 18 to enter the detection mechanism such as Tested in dry chemical test strips.

When the sample solution is serum, the entire process only needs to include quantification and detection. Correspondingly, as shown in FIG. 6, the serum sample is added to the second sample loading cavity 112, and the centrifugation is turned on, so that the serum sample enters the liquid distribution channel 20 through the buffer cavity 15 and finally enters each quantitative cavity In 16, the quantification and detection process can refer to but not limited to the above-mentioned quantification and detection process of serum obtained after separation of a whole blood sample. For serum samples, there is no need to repeat the operation of whole blood separation, and the serum samples are directly added to the second sample addition cavity 112, thus reducing the sample amount and shortening the detection process, which can effectively improve the efficiency of detection.

The microfluidic chip 10 can be used for multiple purposes in one piece, and is used for detecting different types of sample solutions, with simple operation and high flexibility. Moreover, the capillary flow channel is used as a valve, which is faster and more convenient than using water-soluble membranes in related technologies to control sample detection.

The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the various technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, All should be considered as the scope of this specification.

Claims

A microfluidic chip having a sample loading cavity, a separation cavity, a first waste liquid cavity, a first capillary flow channel, a buffer cavity and a quantitative cavity;

The sample adding cavity has a sample hole, the sample adding cavity has a plurality, each of the sample adding cavity is connected with the buffer cavity, and at least one of the sample adding cavity is passed through the buffer cavity in turn. The separation cavity and the first capillary flow channel are connected to the buffer cavity, the buffer cavity is connected to the quantitative cavity, and the separation cavity is also connected to the first waste liquid cavity;

The microfluidic chip has a center of rotation, the separation cavity is farther away from the center of rotation than the sample loading cavity connected to it, and the first waste liquid cavity is farther away from the separation cavity For the rotation center, the buffer cavity is farther away from the rotation center than the sample loading cavity connected to it, and the first capillary flow channel is gradually approached from the end connected to the separation cavity. The direction of the rotation center extends and bends and then extends in a direction away from the rotation center to be connected to the buffer cavity, and the bending position is closer to the rotation relative to the separation cavity and the buffer cavity Center, the quantitative cavity is farther away from the rotation center than the buffer cavity.
The microfluidic chip according to claim 1, further having a second capillary flow channel, one end of the second capillary flow channel is connected to the quantitative cavity, and after being connected to the quantitative cavity, it approaches the The direction of the rotation center extends and bends and then extends in a direction away from the rotation center, so as to discharge the solution to be measured in the quantitative cavity from the other end.
The microfluidic chip according to claim 2, further having a liquid permeation hole, one end of the liquid permeation hole is connected to the second capillary flow channel on the side surface where the second capillary flow channel is located. It is connected to one end where the solution to be tested is discharged, and the other end is open on the other side surface of the microfluidic chip.
The microfluidic chip according to claim 1, further comprising a second waste liquid cavity, the second waste liquid cavity is connected to the separation cavity through an overflow channel, and the overflow channel is opposite to The second waste liquid cavity and the separation cavity are closer to the rotation center.
The microfluidic chip according to any one of claims 1 to 4, further having a liquid separation channel, the liquid separation channel is connected to the buffer cavity and extends from the connection end around the center of rotation to Its other end

There are multiple quantitative cavities, and the multiple quantitative cavities are distributed around the center of rotation on the outer side of the liquid separation channel, and each of the quantitative cavities is connected to the liquid separation channel.
5. The microfluidic chip according to claim 5, further having a first penetration hole and a second penetration hole penetrating the microfluidic chip;

The microfluidic chip has opposite sides of the surface, a first surface and a second surface, the buffer cavity and the liquid distribution channel are located on the first surface and the second surface, respectively. One end of the first penetration hole is connected to the buffer cavity on the first surface, and the other end is connected to the liquid distribution channel on the second surface;

The quantitative cavity is located on the first surface, one end of the second permeation hole is connected to the liquid distribution channel on the second surface, and the other end is on the first surface and corresponds to the quantitative cavity体连接。 Body connection.
The microfluidic chip according to claim 6, further having a third penetration hole and a quality control cavity, the quality control cavity is located on the first surface, and the third penetration hole penetrates the microfluidic chip One end of the third penetration hole is connected to a position near the end of the liquid distribution channel on the second surface, and the other end is connected to the quality control cavity on the first surface.
The microfluidic chip according to claim 6, further comprising a fourth permeation hole and a third waste liquid cavity, the third waste liquid cavity is located on the first surface, and the fourth permeation hole penetrates the In the microfluidic chip, one end of the fourth penetration hole is connected to the tail end of the liquid separation channel on the second surface, and the other end is connected to the third waste liquid cavity on the first surface.
The microfluidic chip according to any one of claims 1-4 and 6-8, wherein some cavities are directly provided with vents for exhausting air, and some cavities are provided on other cavities connected to it. The ventilation hole is used to exhaust air, and the ventilation hole is closer to the rotation center than the cavity to which it is directly connected.
The microfluidic chip according to any one of claims 1-4 and 6-8, wherein the two cavities connected to each other or the cavities and the holes connected to each other are connected by a micro flow channel.
The microfluidic chip according to any one of claims 1-4 and 6-8, wherein the sample loading cavity is arranged around the center of rotation; and/or

The size of the sample application cavity gradually increases from one end of the sample application to the other end thereof.
The microfluidic chip according to any one of claims 1-4 and 6-8, wherein the microfluidic chip is further provided with positioning holes.
An in vitro detection device, comprising the microfluidic chip according to any one of claims 1-12 and a detection mechanism, the detection mechanism is in communication with the quantitative cavity, and the detection mechanism is used to detect the quantitative The sample inside the cavity.
The in vitro detection device according to claim 13, wherein the detection mechanism is a dry chemical test paper.
The in vitro detection device according to claim 14, wherein the dry chemical test paper comprises a support layer and a reaction indicator layer and a diffusion layer stacked on the support layer, and the reaction indicator layer contains The reaction reagent and indicator reagent for the reaction of the target substance in the sample, and the diffusion layer faces the quantitative cavity through its sample inlet.
The in vitro detection device according to any one of claims 13-15, wherein the microfluidic chip is provided with mounting grooves surrounding each of the quantitative chambers, and the detection mechanism is embedded in each of the mounting grooves. The quantitative cavity is connected.