WO2020192168A1

WO2020192168A1 - Microfluidic chip and in vitro testing device containing the microfluidic chip

Info

Publication number: WO2020192168A1
Application number: PCT/CN2019/122795
Authority: WO
Inventors: 蒙玄; 刘洋; 万惠芳; 李文美
Original assignee: 广州万孚生物技术股份有限公司
Priority date: 2019-03-27
Filing date: 2019-12-03
Publication date: 2020-10-01
Also published as: CN110508335A

Abstract

A microfluidic chip (10) and an in vitro testing device (2) containing the microfluidic chip (10). The microfluidic chip (10) is provided with a sample adding cavity (110), a precipitation cavity (130) and a quantification cavity (160); a sample to be tested can be added to the sample adding cavity (110) through a sample adding hole (111), a solid precipitate can be separated from a liquid by means of centrifugal separation, so as to obtain a solution to be tested containing a target substance, and said solution in the sample adding cavity (110) and a first microfluidic channel (120) can drive the liquid to flow by means of the capillary force of a capillary flow channel (140), finally forming a siphoning action and an external centrifugal action to enable said solution to flow into the quantification cavity (160), so as to achieve the quantification of said solution. The microfluidic chip (10) has a relatively simple structure, is easy to manufacture and mold, and can be widely promoted and used. The in vitro testing device (2) has a testing unit (20) and can directly test a solution to be tested which has been quantified in a quantification cavity (160), being easy to operate and having high testing efficiency.

Description

Microfluidic chip and in vitro detection device containing the microfluidic chip

Technical field

The invention relates to the technical field of in vitro diagnostics, in particular to a microfluidic chip and an in vitro detection device containing the microfluidic chip.

Background technique

In Vitro Diagnosis (IVD) refers to the technology of taking samples (blood, body fluids, tissues, etc.) from the human body for detection and analysis to diagnose diseases. The detection process requires corresponding instruments and reagents, and these instruments and reagents It constitutes an in vitro diagnostic system. In-vitro diagnostic systems are roughly divided into two types: one is represented by the testing center laboratory, which has the characteristics of system modularization and automation, and conducts pipeline inspections on samples, which also has high throughput, high efficiency, and high sensitivity. However, the entire system also has disadvantages such as high cost, large volume, and professional operation. It is mainly used in large hospitals; the other is represented by point-of-care testing (POCT) , Its system has the characteristics of integration and miniaturization, which can carry out sample inspection anytime and anywhere, which also has the advantages of affordable price, simple operation, and timely result reporting. The advantages of microfluidic chip technology are high functional integration, miniaturization, and automation. Therefore, microfluidic technology is widely used in the POCT field. However, the traditional microfluidic chip used for POCT generally has the problem of complex structure, and therefore the price is relatively expensive, which limits its further application in the POCT field.

Summary of the invention

Based on this, it is necessary to provide a microfluidic chip with a relatively simple structure and capable of separating and quantifying samples, and an in vitro detection device containing the microfluidic chip.

A microfluidic chip. The microfluidic chip is provided with a separation and quantification unit. The separation and quantification unit includes a sample addition cavity, a first microchannel, a precipitation cavity, a capillary channel, and a second microchannel And a quantitative cavity; the sample loading cavity is provided with a sample loading hole, the sample loading cavity and the precipitation cavity are communicated through the first micro flow channel, and the first micro flow channel passes through the capillary The flow channel is in communication with the second micro flow channel, and the second micro flow channel is in communication with the quantitative cavity;

The microfluidic chip has a center of rotation, the precipitation chamber is farther from the center of rotation than the sample loading chamber, and the capillary channel is closer to the center of rotation after being connected to the first microchannel. It extends in the direction of and bends and then extends in a direction away from the rotation center to connect with the second micro flow channel, and the quantitative cavity is farther from the rotation center than the capillary flow channel.

In one of the embodiments, the separation and quantification unit further includes a waste liquid cavity, the waste liquid cavity is in communication with the second microchannel, and the waste liquid cavity is located on the second microchannel. Downstream of the quantitative cavity, the waste liquid cavity is farther from the rotation center than the capillary flow channel.

In one of the embodiments, the sample adding cavity is further provided with a first vent hole.

In one of the embodiments, a baffle is provided in the sample loading cavity between the sample loading hole and the first vent hole.

In one of the embodiments, the sample adding hole and the first vent hole are both arranged on the sample adding cavity close to the rotation center.

In one of the embodiments, the width of the capillary flow channel is 0.1 mm to 0.2 mm, and the depth is 0.1 mm to 0.2 mm; or

The width of the capillary flow channel is 0.2mm-0.5mm, and the depth is 0.2mm-0.5mm, and the flow channel wall of the capillary flow channel is surface treated with PEG4000.

In one of the embodiments, the second microfluidic channel is provided with a second ventilation hole, the second ventilation hole is located downstream of the cavity structure connected to the second microfluidic channel, and the second ventilation hole Relative to the cavity structure connected to the second micro flow channel, it is closer to the rotation center.

In one of the embodiments, the portion of the second micro-channel downstream of the cavity structure to which it is connected is bent and extended in a direction close to the rotation center, and the second vent is provided in the second micro-channel. The end of the runner.

In one of the embodiments, there are multiple separation and quantitative units, and multiple separation and quantitative units are arranged around the same rotation center.

In one of the embodiments, the microfluidic chip is in the shape of a disc, a plurality of the separation and quantitative units are evenly distributed on the microfluidic chip, and the middle of the microfluidic chip has a rotating mounting part, so The center of the rotation mounting part is the rotation center.

In one of the embodiments, the microfluidic chip includes a chip body and a transparent cover film covering the chip body, and the chip body and the transparent cover film cooperate to form each cavity of the separation and quantitative unit Structure and runner structure.

An in vitro detection device includes the microfluidic chip described in any of the above embodiments and a detection unit, and the detection unit is used to detect a sample in the quantitative cavity.

In one of the embodiments, the detection unit is a freeze-dried reagent set in the quantitative cavity.

In one of the embodiments, the quantitative cavity has a permeation hole, the permeation hole is covered with a water-soluble film, and the sampling port of the detection unit is connected to the permeation hole and is separated by the water-soluble film .

In one of the embodiments, the detection unit 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 water-soluble membrane through the injection port.

In one of the embodiments, the microfluidic chip is provided with a mounting groove around the penetration hole, and the detection unit is embedded in the mounting groove.

The microfluidic chip is equipped with a sample loading cavity, a sedimentation cavity and a quantitative cavity. The sample to be tested can be added to the sample loading cavity through the sample hole, and the solid precipitate can be separated from the liquid by centrifugal separation. For the test solution containing the target substance, the test solution in the sample loading chamber and the first microchannel can drive the liquid to flow through the capillary force of the capillary channel, and finally form a siphon effect and external centrifugal action to flow into the quantitative cavity to achieve the Measure the quantification of the solution. The microfluidic chip has a relatively simple structure, is easy to manufacture and shape, and can be widely promoted and used.

The in-vitro detection device has a detection unit, which can directly detect the quantitative solution to be tested in the quantitative cavity, and has simple operation and high detection efficiency.

Description of the drawings

FIG. 1 is a schematic diagram of the front structure of a microfluidic chip according to an embodiment of the present invention;

2 is a schematic diagram of the backside structure of the microfluidic chip shown in FIG. 1;

Fig. 3 is a side view of the microfluidic chip shown in Fig. 1 with a detection unit;

Figures 4-1, 4-2, 4-3 and 4-4 are schematic diagrams of the process of plasma (or serum) separation and quantification of the whole blood sample by the microfluidic chip shown in Figure 1, Figure 4-2-1, 4 -3-1 and 4-4-1 are corresponding partial enlarged schematic diagrams;

Figures 5-1, 5-2, and 5-3 are schematic diagrams of the process of dissolving the water-soluble membrane into the detection unit by plasma (or serum) of an in vitro detection device according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of the structure of a dry chemical test paper according to an embodiment.

detailed description

In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

It should be noted that when a component is referred to as being "disposed on" or "mounted on" another component, it can be directly on the other component or a centered component may also exist. When an element is considered to be "connected" to another element, it can be directly connected to the other element or an intermediate element may be present at the same time.

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 the present invention. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The term "and/or" as used herein includes any and all combinations of one or more related listed items.

1 and FIG. 2, an embodiment of the present invention provides a microfluidic chip 10 on which a separation and quantification unit 100 is provided. The separation and quantification unit 100 includes a sample addition cavity 110, a first micro flow channel 120, a sedimentation cavity 130, a capillary flow channel 140, a second micro flow channel 150 and a quantification cavity 160. The sample adding cavity 110 is used to hold the sample to be tested, and is provided with a sample adding hole 111. The sedimentation chamber 130 is used to collect useless objects in the sample to be tested with a relatively high density of solids. The sample loading cavity 110 and the sedimentation cavity 130 are in communication with each other through the first micro flow channel 120. The first micro channel 120 communicates with the second micro channel 150 through the capillary channel 140. The second micro flow channel 150 is in communication with the quantitative cavity 160. The quantitative cavity 160 is used to quantify the sample solution to be tested.

In this embodiment, the microfluidic chip 10 has a center of rotation 18. The sedimentation cavity 130 is farther away from the rotation center 18 than the sample addition cavity 110. The capillary flow channel 140 extends from the connection with the first micro flow channel 120 in the direction approaching the rotation center 18 (may be each gradually approaching the rotation center 18, such as but not limited to the radial direction), and then bends away from the rotation center. The direction of 18 (may be a direction gradually away from the rotation center 18, for example, but not limited to a radial direction) extends to connect with the second micro channel 150. The quantitative cavity 160 is farther from the center of rotation than the capillary flow channel 140.

In the specific example shown in the figure, the bottom of the end connecting the sample adding cavity 110 and the first micro flow channel 120 is inclined to facilitate the flow of the sample to be tested into the first micro flow channel 120.

The size of the first microfluidic channel 120 needs to be able to pass through the useless objects in the sample to be tested. For example, for a whole blood sample, when separating plasma or serum, the first microfluidic channel 120 needs to satisfy Of blood cells can pass through. In the specific example shown in the figure, the first micro flow channel 120 has a branch portion 121 extending in a direction close to the rotation center 18, and the capillary flow channel 140 is connected to the end of the branch portion 121 of the first micro flow channel 120.

In a specific example, the separation and quantitative unit 100 further includes a waste liquid cavity 170. The waste liquid chamber 170 is used to collect excess solution to be tested. The waste liquid cavity 170 is in communication with the second micro flow channel 150. The waste liquid cavity 170 is located downstream of the quantitative cavity 160 on the second micro flow channel 150 to receive the excess solution to be tested. The waste liquid cavity 170 is farther away from the rotation center 18 than the capillary flow channel 140. When there is a solution to be tested in the waste liquid cavity 170, it means that the quantitative cavity 160 located upstream of it is filled with the solution to be tested, so that the quantitative cavity 160 can quantify the solution to be tested.

In a specific example, the sample adding cavity 110 is further provided with a first vent 112. The first vent hole 112 is used for ventilation, which can facilitate the addition of the sample, and avoid the influence of the sample entry due to the increase of the air pressure inside the cavity when the sample is added.

Further, in a specific example, a baffle 113 is provided between the sample adding hole 111 and the first vent hole 112 in the sample adding cavity 110. The baffle 113 can prevent the sample from reaching one side of the first vent hole 112 after the sample is added, and prevent the sample from flowing out of the first vent hole 112.

Preferably, the sample addition hole 111 and the first vent hole 112 are both arranged on the sample addition cavity 110 close to the rotation center 18, so that when the sample is rotated and centrifuged to make the sample flow to the side of the sample addition cavity 110 far from the rotation center, The sample is placed to flow out from the sample loading hole 111 and the first vent hole 112, so that the sample flows smoothly into the first micro flow channel 120 and the sedimentation cavity 130.

The capillary flow channel 140 has a V shape, and its curved part is close to the rotation center 18. In a specific example, the capillary flow channel 140 has a width of 0.1 mm to 0.2 mm and a depth of 0.1 mm to 0.2 mm; or the capillary flow channel 140 has a width of 0.2 mm to 0.5 mm and a depth of 0.2 mm to 0.5 mm. When the capillary channel 140 has a width of 0.1mm～0.2mm and a depth of 0.1mm～0.2mm, no surface treatment is required. When the capillary channel 140 has a width of 0.2mm～0.5mm and a depth of 0.2mm～0.5mm, The flow channel wall of the capillary flow channel 140 is preferably surface-treated with PEG4000. Further preferably, the width of the capillary flow channel 140 is 0.2 mm, and the depth is also 0.2 mm. After the capillary channel 140 enters the sample solution, the sample solution can flow to the other end of the sample solution by capillary action, and finally form a siphon effect between the first micro channel 120 and the second micro channel 150.

The PEG4000 surface treatment can be, but is not limited to, adding a 1 wt% PEG4000 solution to the capillary flow channel 140 and forming it after natural drying. The surface treatment of PEG4000 is beneficial to increase the capillary force of the capillary channel 140, and PEG4000 is an inert substance in the reaction system, and generally does not react with samples and detection reagents, and thus does not affect the detection results.

In a specific example, the second micro flow channel 150 is provided with a second vent hole 151. The second vent hole 151 is located downstream of the cavity structure (for example, the quantitative cavity 160 and the waste liquid cavity 170) connected to the second micro flow channel 150, and the second vent hole 151 is connected to the second micro flow channel 150 The cavity structure is closer to the center of rotation 18. The second vent hole 151 also plays a role of ventilating, facilitating the sample solution to be tested to smoothly flow into the second micro flow channel 150 and finally flow into the quantitative cavity 160 and the waste liquid cavity 170.

It can be understood that in other specific examples, the first vent 112 and the second vent 151 can be selected. For example, there may be only the first vent 112 or the second vent 151, wherein the second vent 151 is Choose one of the best.

Further, the part of the second micro-channel 150 downstream of the cavity structure connected to it is bent and extended in a direction close to the rotation center 18, and the second vent hole 151 is provided at the end of the second micro-channel 150, which can effectively The sample solution is prevented from flowing out from the second vent hole 151.

Please refer to FIG. 3, in a specific example, the microfluidic chip 10 includes a chip body 11 and a transparent cover film 12 covering the chip body 11. The chip body 11 and the transparent cover film 12 cooperate to form the cavity structure and the flow channel structure of the separation and quantitative unit 100. Specifically, the grooves of each cavity structure and flow channel structure are pre-formed on the chip body 11. As shown in FIG. 2, each hole is opened on the back of the chip body, and is subsequently covered by a transparent cover film 12 and sealed in The front surface of the chip body 11 can be formed to complete the packaging of the cavity structure and the flow channel structure, forming a complete cavity structure and the flow channel structure.

The transparent cover film 12 can be, but is not limited to, transparent tape or transparent pressure-sensitive adhesive, etc., which cooperates with the chip body 11 to form the entire microfluidic chip 10, which is simple to assemble and does not require complicated and expensive ultrasonic welding technology. , Can significantly reduce production costs. It can be understood that, 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.

In a specific example, there are multiple separation and quantitative units 100, and the multiple separation and quantitative units 100 are arranged around the same rotation center 18. Multiple quantification units 100 can realize multi-sample single detection, and can also realize single-sample multiple detection, with good consistency and high integration, which significantly improves the throughput of single detection.

Preferably, for example, in the specific example shown in the figure, the microfluidic chip 10 is in the shape of a disc, a plurality of separate quantitative units 100 are evenly distributed on the microfluidic chip 10, and the microfluidic chip 10 has a rotating mounting part 180 in the middle. , The center of the rotating mounting portion 180 is the center of rotation 18. The rotating mounting part 180 may be various types of clamping slots or clamping posts.

The microfluidic chip 10 is provided with a sample loading cavity 110, a precipitation cavity 130, and a quantitative cavity 160. The sample to be tested can be added to the sample loading cavity 110 through the sample hole 111, and the solid can be precipitated by centrifugal separation. The substance is separated from the liquid to obtain the test solution containing the target substance. The test solution in the sample loading chamber 110 and the first microchannel 120 can drive the liquid to flow through the capillary force of the capillary channel 140, and finally form a siphon effect and the outside world. The centrifugal action flows into the quantification cavity 160 to realize the quantification of the solution to be tested. The microfluidic chip 10 has a relatively simple structure, is easy to manufacture and shape, and can be widely promoted and used.

Referring to FIGS. 2, 3, FIGS. 5-1, 5-2 and 5-3, the present invention also provides an in vitro detection device 2, which includes the aforementioned microfluidic chip 10 and a detection unit 20. The detection unit 20 is used to detect the sample in the quantitative cavity 160 of the microfluidic chip 10.

In a specific example, the detection unit 20 is a freeze-dried reagent arranged in the quantitative cavity 160. The freeze-dried reagent is placed in the quantitative cavity 160. When the sample solution flows into the quantitative cavity 160, the freeze-dried reagent can be dissolved and reacted with it, and the result of the reaction can be detected.

Due to the complicated production process of the freeze-dried reagents and the high cost, in another specific example, the detection unit 20 is external. Specifically, the quantitative cavity 160 has a permeation hole 161, and the permeation hole 161 is covered with a water-soluble film 162. The injection port 21 of the detection unit 20 is connected to the permeation hole 161 and is separated by a water-soluble membrane 162.

Further, in a specific example, the detection unit 20 is a dry chemical test paper. As shown in FIG. 6, the dry chemical test paper 20 includes a supporting layer 22 and a reaction indicating layer 23 and a diffusion layer 24 stacked on the supporting layer 22 in sequence. The reaction indicator layer 23 contains a reaction reagent and an indicator reagent that can react with the target substance in the sample to be tested. The reaction indicating layer 23 may be one layer or multiple layers. For example, in the specific example shown in FIG. 6, the reaction indicating layer 23 includes two layers of an indicating layer 231 and a reagent layer 232, and the indicating layer 231 is close to the supporting layer 22. , Which contains a color indicator reagent, the reagent layer 232 is close to the diffusion layer 24, and contains a reaction reagent capable of reacting with the target substance; in addition, the reagents contained in the indicator layer 232 and the reagent layer 232 can also be exchanged or appropriately mixed. The diffusion layer 24 faces the water-soluble film 162 through the injection port 21.

Furthermore, the microfluidic chip 10 is provided with a mounting groove around the penetration hole. The detection unit 20 is embedded in the installation groove.

The in vitro detection device 2 has a detection unit 20, which can directly detect the quantified sample solution to be tested in the quantitative cavity 160, with simple operation and high detection efficiency. Taking the whole blood sample loading test as an example, the specific test process of the in vitro test device 2 using dry chemical test paper can be referred to as follows:

Please refer to Figures 4-1, 4-2, 4-3 and 4-4, and add a certain amount of whole blood to the sample chamber 110 through the sample hole 111, and six different samples can be added in sequence;

After the sample is added, install the rotary mounting part 180 of the in vitro detection device 2 in the supporting rotary centrifugal instrument, turn on the instrument to rotate, the whole blood is subjected to centrifugal force, and the red blood cells are deposited in the sedimentation chamber 130, and the serum or plasma is separated To the upper part of the precipitation chamber 130, the second micro flow channel 120, and the sample adding chamber 110;

When the microfluidic chip 10 rotates, serum or plasma is only partially filled in the capillary channel 140, as shown in Figures 4-2-1 and 4-3-1, the liquid level exceeds the inlet end 140a of the capillary channel 140 , Without exceeding the curved part 140b of the capillary flow channel 140; when the microfluidic chip 10 stops rotating, under the capillary force of the capillary flow channel 140, the serum or plasma crosses the curved part 140b and reaches the end 140c of the capillary flow channel 140 , Since the point at the end 140c is lower than the height of the liquid level in the sample loading cavity 110 (which is farther from the rotation center 18 than the liquid level in the sample loading cavity 110), a siphon effect can be formed;

When the capillary channel 140 is filled with serum or plasma, the microfluidic chip 10 is controlled to rotate again, because the end 140c is farther from the center of rotation 18 than the liquid level in the sample cavity 110, as shown in Figures 4-3-1 and 4- As shown in 4-1, under the action of siphoning and centrifugal force, serum or plasma enters the quantitative cavity 160 through the second microchannel 150. When the quantitative cavity 160 is filled with serum or plasma, the sample solution to be tested is completed Quantitatively, the excess serum or plasma enters the back section of the second micro-channel 150 or the waste liquid cavity 170; preferably, the instrument will determine whether there is in the back section of the second micro-channel 150 or the waste liquid cavity 170. The liquid judges whether the quantitative cavity 160 is full of liquid. When it is detected that there is liquid in the back section of the second microfluidic channel 150 or the waste liquid cavity 170, it can be determined that the quantitative cavity 160 is full of liquid. Whether the cavity 160 is full of liquid;

Turn on and turn when the capillary channel 140 is filled with serum or plasma until the quantitative cavity 160 is filled with liquid, generally within 10s. When the quantitative cavity 160 is filled with liquid, control the microfluidic chip 10 to stop rotating and stand still , The liquid will be temporarily enclosed in the quantitative cavity 160. As time goes by, the liquid will gradually dissolve the water-soluble film 162 covered at the permeation hole 161. The dissolution process takes about 1 min, as shown in Figures 5-1, 5-2 and Shown in 5-3;

After the water-soluble film 162 is dissolved, the liquid generally does not flow into the detection unit (dry chemical test paper) 20 due to its own weight. The microfluidic chip 10 needs to be rotated under control. It can rotate at a low speed of 1800rpm～2000rpm to make the quantitative chamber The quantified sample solution in 160 enters the sample inlet 21 of the detection unit 20;

The sample solution is sequentially diffused through the diffusion layer 24 to the reaction indicator layer 23 for color reaction. The depth of the color can reflect the concentration of the test substance. The signal can be collected through the detection hole 25 of the detection unit, and finally converted into the concentration data of the test substance. . The in vitro detection device 2 can solve the problems of low sensitivity and stability of dry chemical test paper whole blood, and has the advantages of high detection throughput and low cost.

The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the 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.

The above-mentioned embodiments only express several embodiments of the present invention, and the descriptions are more specific and detailed, but they should not be understood as limiting the scope of the invention patent. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can be made, and these all fall within the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention should be subject to the appended claims.

Claims

A microfluidic chip, characterized in that a separation and quantification unit is provided on the microfluidic chip, and the separation and quantification unit includes a sample addition chamber, a first micro flow channel, a precipitation chamber, a capillary flow channel, and a second Two micro flow channels and a quantitative cavity; the sample loading cavity is provided with a sample loading hole, the sample loading cavity and the precipitation cavity are communicated through the first micro flow channel, and the first micro flow channel Communicate with the second micro flow channel through the capillary flow channel, and the second micro flow channel communicates with the quantitative cavity;

The microfluidic chip has a center of rotation, the precipitation chamber is farther from the center of rotation than the sample loading chamber, and the capillary channel is closer to the center of rotation after being connected to the first microchannel. It extends in the direction of and bends and then extends in a direction away from the rotation center to connect with the second micro flow channel, and the quantitative cavity is farther from the rotation center than the capillary flow channel.
The microfluidic chip according to claim 1, wherein the separation and quantification unit further comprises a waste liquid cavity, the waste liquid cavity is in communication with the second microfluidic channel, and the waste liquid cavity The second micro flow channel is located downstream of the quantitative cavity, and the waste liquid cavity is farther from the rotation center than the capillary flow channel.
3. The microfluidic chip of claim 1, wherein the sample loading cavity is further provided with a first vent.
8. The microfluidic chip of claim 3, wherein a baffle plate is provided in the sample loading cavity between the sample loading hole and the first vent hole.
8. The microfluidic chip of claim 3, wherein the sample application hole and the first vent hole are both arranged on the sample application cavity close to the rotation center.
The microfluidic chip of claim 1, wherein the capillary flow channel has a width of 0.1 mm to 0.2 mm and a depth of 0.1 mm to 0.2 mm; or

The width of the capillary flow channel is 0.2mm-0.5mm, and the depth is 0.2mm-0.5mm, and the flow channel wall of the capillary flow channel is surface treated with PEG4000.
The microfluidic chip of claim 1, wherein the second microfluidic channel is provided with a second vent hole, and the second vent hole is located in the cavity structure connected on the second microfluidic channel. Downstream, and the second vent hole is closer to the rotation center than the cavity structure connected to the second micro flow channel.
The microfluidic chip according to claim 7, wherein a part of the second microfluidic channel located downstream of the cavity structure to which it is connected is bent and extends in a direction close to the rotation center, and the second The air vent is provided at the end of the second micro flow channel.
8. The microfluidic chip according to any one of claims 1 to 8, wherein there are multiple separation and quantitative units, and multiple separation and quantitative units are arranged around the same center of rotation.
The microfluidic chip of claim 9, wherein the microfluidic chip is in the shape of a disc, a plurality of the separation and quantification units are evenly distributed on the microfluidic chip, and the microfluidic chip The middle of the chip has a rotating mounting part, and the center of the rotating mounting part is the rotation center.
The microfluidic chip according to any one of claims 1 to 8 and 10, wherein the microfluidic chip comprises a chip body and a transparent cover film covering the chip body, the chip body Cooperating with the transparent cover film to form each cavity structure and flow channel structure of the separation and quantitative unit.
An in vitro detection device, characterized by comprising the microfluidic chip according to any one of claims 1 to 11 and a detection unit, the detection unit being used for detecting a sample in the quantitative cavity.
The in vitro detection device of claim 12, wherein the detection unit is a freeze-dried reagent set in the quantitative cavity.
The in vitro detection device according to claim 12, wherein the quantitative cavity has a permeable hole, the permeable hole is covered with a water-soluble film, and the sampling port of the detection unit is connected to the permeable hole. Separated by the water-soluble membrane.
The in vitro detection device of claim 14, wherein the detection unit is a dry chemical test paper.
The in vitro detection device according to claim 15, 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 to be tested, and the diffusion layer faces the water-soluble membrane through the sample inlet.
The in vitro detection device according to any one of claims 14 to 16, wherein the microfluidic chip is provided with an installation groove around the penetration hole, and the detection unit is embedded in the installation groove.