Microfluidic chip and in vitro detection system

Abstract

The present invention discloses a microfluidic chip and an in vitro detection system containing the microfluidic chip. After adding a sample solution to a sample adding cavity of the microfluidic chip, the sample solution enters a quantitative cavity and a first waste liquid cavity through a first connecting microchannel through rotational centrifugation, and gradually fills up the first waste liquid cavity and the quantitative cavity, and the excess sample solution overflows into a second waste liquid cavity through an overflow microchannel, and solid impurities in the sample solution can be separated from a solution to be tested by further centrifugation, and the solid impurities are centrifugally precipitated into the first waste liquid cavity, and the solution to be tested is left in the quantitative cavity close to the proximal end, thereby achieving separation and quantification of the sample solution. The microfluidic chip only needs one centrifugation after adding the sample solution to achieve separation and quantification of impurities in the sample solution and a target solution to be tested, without excessive centrifugation operations, and is therefore easy to operate, requires a short waiting time, and significantly improves the efficiency of sample processing.

Description

Technical Field

[0001] The present invention relates to the technical field of in vitro diagnosis, and in particular to a microfluidic chip and an in vitro detection system. Background Art

[0002] The in vitro diagnostic industry (IVD) belongs to the pharmaceutical and biological industry. It refers to the use of in vitro detection reagents and instruments to detect and calibrate samples such as blood, body fluids, and tissues taken from the human body in order to prevent, diagnose, treat, detect, observe, evaluate health, predict genetic diseases, etc. In vitro diagnosis is divided into three categories according to methodology: biochemical diagnosis, immunological diagnosis, and molecular diagnosis, as well as bedside 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 specific substrates, and then quantitatively detects the concentration of the target through instruments to deduce certain biochemical indicators of the human body. Traditional biochemical diagnosis needs to be tested on a large biochemical instrument, which leads to problems such as high reagent consumption and insufficient flexibility; the general dry biochemical POCT diagnostic method has a low test throughput, and generally can only test one or several samples and one or several items at a time. Microfluidics chip technology can integrate basic operating units such as sample preparation, reaction, separation, and detection in biological, chemical, and medical analysis processes on the chip, automatically completing the entire analysis process and greatly improving detection efficiency. It also has the advantages of miniaturization and automation, and is therefore increasingly widely used in the POCT field.

[0003] In the field of biochemical testing, Abaxis in the United States is the first company to develop microfluidic chips for biochemical testing. Domestic companies such as Tianjin Micro-Nano Chip and Chengdu Smart have developed similar microfluidic chips. The quantification and distribution process of whole blood samples in traditional chips often requires the separation of whole blood and the quantification process of serum to be separated, so multiple centrifugation and quantification are required, which makes the sample processing time longer and causes the detection time to be too extended. Summary of the invention

[0004] Based on this, it is necessary to provide a microfluidic chip that can improve sample processing efficiency and an in vitro detection system containing the microfluidic chip.

[0005] A microfluidic chip has a separation and quantitative unit, the separation and quantitative unit comprises a sample addition cavity, a first connecting microfluidic channel, a quantitative cavity, a first waste liquid cavity, an overflow microfluidic channel and a second waste liquid cavity; the sample addition cavity has a sample addition hole; the quantitative cavity is connected to the sample addition cavity through the first connecting microfluidic channel; the first waste liquid cavity is connected to the quantitative cavity; the second waste liquid cavity is connected to the quantitative cavity through the overflow microfluidic channel;

[0006] The separation quantitative unit has a proximal end close to the rotation center during centrifugation; the sample addition chamber is closer to the proximal end than the quantitative chamber; the quantitative chamber is closer to the proximal end than the first waste liquid chamber; when the quantitative chamber is filled with liquid, excess liquid can enter the second waste liquid chamber through the overflow microchannel, and the overall distance between the second waste liquid chamber and the proximal end is not greater than the distance between the quantitative chamber and the proximal end.

[0007] In one embodiment, the sample loading hole is closer to the proximal end than the connection position between the sample loading chamber and the first connecting microfluidic channel.

[0008] In one embodiment, the sample loading chamber further has a first vent hole, and the first vent hole is closer to the proximal end than the connection position between the sample loading chamber and the first connecting microfluidic channel.

[0009] In one embodiment, the connection between the sample loading chamber and the first connecting microfluidic channel is funnel-shaped.

[0010] In one embodiment, the microfluidic chip further includes a quality control chamber, the quality control chamber is connected to the second waste liquid chamber, and the quality control chamber is farther away from the proximal end than the second waste liquid chamber.

[0011] In one embodiment, the microfluidic chip also includes a second connecting microchannel connected to the second waste liquid chamber, the second connecting microchannel gradually extends from one end connected to the second waste liquid chamber toward the proximal end, and is provided with a second air hole at the other end.

[0012] In one embodiment, the microfluidic chip further includes a third connecting microfluidic channel, and the first waste liquid chamber is connected to the quantitative chamber through the third connecting microfluidic channel.

[0013] In one embodiment, the microfluidic chip further includes a liquid outlet microchannel, one end of which is connected to the quantitative cavity, and the other end of which has a permeation hole.

[0014] In one embodiment, the liquid outlet microchannel includes a capillary channel, one end of the capillary channel is connected to the third connecting microchannel, and the other end is provided with the permeation hole;

[0015] The capillary channel gradually extends from one end connected to the third connecting microchannel toward the proximal end and bends to extend away from the proximal end; the bending apex of the capillary channel is closer to the proximal end than the connection position between the quantitative cavity and the first connecting microchannel.

[0016] In one embodiment, the liquid outlet microfluidic channel further includes a fourth connecting microfluidic channel, one end of the fourth connecting microfluidic channel is connected to the third connecting microfluidic channel, and the other end of the fourth connecting microfluidic channel is connected to the capillary channel.

[0017] In one embodiment, the fourth connecting microfluidic channel gradually extends from an end connected to the third connecting microfluidic channel toward the proximal end to connect to the capillary channel.

[0018] In one embodiment, each of the microfluidic chips is provided with a separation and quantification unit.

[0019] In one of the embodiments, the microfluidic chip also has a clamping portion for mounting on a centrifugal device.

[0020] In one embodiment, the clamping portion is located at the proximal end.

[0021] An in vitro detection system comprises the microfluidic chip and a detection mechanism as described in any one of the above embodiments, wherein the detection mechanism is connected to the quantitative cavity and is used to detect a sample in the quantitative cavity.

[0022] In one embodiment, the in vitro detection system further comprises a centrifugal tray for installation on a centrifugal device, and the centrifugal tray is provided with a mounting position for placing the microfluidic chip.

[0023] In one embodiment, the centrifugal tray has a rotating mounting portion in the middle, and there are multiple mounting positions, which are arranged around the rotating mounting portion.

[0024] In one of the embodiments, the centrifugal tray is provided at the mounting position with at least one observation hole for observing the state of the microfluidic chip and / or the detection result.

[0025] In one embodiment, the detection mechanism is a dry chemical test paper.

[0026] In one embodiment, the dry chemical test paper includes a support layer and a reaction indicator layer and a diffusion layer stacked in sequence on the support layer, the reaction indicator layer contains a reaction reagent and an indicator reagent that can react with a target substance in a sample to be tested, and the diffusion layer faces the permeation hole through the injection port.

[0027] In one embodiment, the microfluidic chip is provided with mounting grooves around the permeation holes of the separation and quantification unit, and the detection mechanism is embedded in each of the mounting grooves.

[0028] The separation and quantitative unit of the above-mentioned microfluidic chip has a sample addition cavity, a first connecting microfluidic channel, a quantitative cavity, a first waste liquid cavity, an overflow microfluidic channel and a second waste liquid cavity. Each cavity and the microfluidic channel cooperate to form a communicating vessel structure. After adding the sample solution to the sample addition cavity, the sample solution enters the quantitative cavity and the first waste liquid cavity through the first connecting microfluidic channel through rotation centrifugation, and gradually fills up the first waste liquid cavity and the quantitative cavity. The excess sample solution overflows into the second waste liquid cavity through the overflow microfluidic channel. Through further centrifugation, the solid impurities in the sample solution can be separated from the solution to be tested. The solid impurities are centrifugally precipitated into the first waste liquid cavity, and the solution to be tested remains in the quantitative cavity close to the proximal end, thereby realizing the separation and quantification of the sample solution. When detection is required, the detection mechanism can be used to detect the quantitative solution to be tested in the quantitative cavity.

[0029] After adding the sample solution, the microfluidic chip only needs one centrifugation to separate and quantify the impurities in the sample solution and the target solution to be tested, without the need for excessive centrifugation operations. Therefore, the operation is simple, the waiting time is short, and the efficiency of sample processing is significantly improved.

[0030] Furthermore, the microfluidic chip is provided with a liquid outlet microchannel including a capillary flow channel, the capillary flow channel gradually extends from one end connected to the third connecting microchannel in a direction close to the proximal end and bends to extend in a direction away from the proximal end, and the bending apex position of the capillary flow channel is closer to the proximal end than the connection position between the quantitative cavity and the first connecting microchannel. In this way, during the centrifugal separation and quantification of the sample solution, since the centrifugal force is greater than the capillary force in the capillary flow channel, the sample solution will not break through the bending apex of the capillary flow channel, and the capillary flow channel can play the role of closing a "valve". During subsequent detection, under the condition of low-speed centrifugation, the solution to be tested in the quantitative cavity will continue to advance along the capillary flow channel under the action of capillary force and break through the bending apex position of the capillary flow channel. The "valve" is opened, and under the action of siphon, the solution to be tested continues to advance and seeps out of the infiltration hole to the detection mechanism for detection.

[0031] Using capillary channels as valves to control the contact reaction between samples and detection mechanisms can replace traditional delayed opening mechanisms such as water-soluble membranes or valves, making the sampling and detection process more stable and reliable. At the same time, it simplifies the chip assembly process and helps reduce production costs.

[0032] Furthermore, by separating the microfluidic chip from the centrifugal tray, multiple microfluidic chips can be freely assembled on one centrifugal tray, thereby achieving free matching of test items and test samples, which is beneficial to improving the overall flexibility of the in vitro detection system. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 , Figure 2 and Figure 3 The front, back and side schematic diagrams of the microfluidic chip according to one embodiment of the present invention are shown respectively;

[0034] Figure 4 and Figure 5 Respectively Figure 1 Schematic diagram of the front and back structures of the centrifugal tray matching the microfluidic chip shown;

[0035] Figure 6 for Figure 1 The microfluidic chip shown is Figure 4 Schematic diagram of the assembly of the centrifuge picture shown;

[0036] Figure 7-1 , Figure 7-2 and Figure 7-3 They are Figure 1 The schematic diagram of the process of separation and quantification of sample solution by the microfluidic chip shown. Figure 7-2-1 It is a local enlarged schematic diagram;

[0037] Figure 8-1 and Figure 8-2 Use Figure 1 Schematic diagram of the detection process of the microfluidic chip shown.

[0038] The following are the descriptions of the reference numerals:

[0039] 10: microfluidic chip, 11: proximal end, 12: clamping part; 13: chip body, 14: transparent cover film, 15: mounting groove;

[0040] 100: separation and quantitative unit, 110: sample loading chamber, 111: sample loading hole, 112: first vent hole, 120: first connecting microfluidic channel, 130: quantitative chamber, 140: first waste liquid chamber, 150: overflow microfluidic channel, 160: second waste liquid chamber, 170: outlet microfluidic channel, 171: permeation hole, 172: capillary channel, 172a, 172b and 172c are different positions of the capillary channel, 173: fourth connecting microfluidic channel, 180: quality control chamber, 190: second connecting microfluidic channel, 191: second vent hole, 200: third connecting microfluidic channel;

[0041] 20: centrifugal tray, 21: mounting position, 22: rotating mounting part, 23: detection hole, 24: quality control hole. DETAILED DESCRIPTION

[0042] 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 present invention are given 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.

[0043] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected" or "communicating" with another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0045] Please combine Figure 1 and Figure 2 An embodiment of the present invention provides a microfluidic chip 10 having a separation and quantification unit 100. The separation and quantification unit 100 includes a sample addition chamber 110, a first connecting microchannel 120, a quantification chamber 130, a first waste liquid chamber 140, an overflow microchannel 150 and a second waste liquid chamber 160.

[0046] The sample adding chamber 110 has a sample adding hole 111. The sample solution can be added to the sample adding chamber 110 from the sample adding hole 111. The quantitative chamber 130 is connected to the sample adding chamber 110 through the first connecting microchannel 120. The quantitative chamber 130 is used to achieve the quantitative measurement of the solution to be tested. The first waste liquid chamber 140 is connected to the quantitative chamber 130. The first waste liquid chamber 140 is used to fill the excess sample solution and the fixed impurity precipitation after separation. The second waste liquid chamber 160 is connected to the quantitative chamber 130 through the overflow microchannel 150. The second waste liquid chamber 160 is used to fill the excess sample solution.

[0047] In this embodiment, the separation quantitative unit 100 has a proximal end 11 close to the rotation center during centrifugation. The sample addition chamber 110 is closer to the proximal end 11 than the quantitative chamber 130. The quantitative chamber 130 is closer to the proximal end 11 than the first waste liquid chamber 140. When the quantitative chamber 130 is filled with liquid, the excess liquid can enter the second waste liquid chamber 160 through the overflow microchannel 150, and the distance between the second waste liquid chamber 160 and the proximal end 11 is not greater than the distance between the quantitative chamber 130 and the proximal end 11.

[0048] After adding the sample solution to the sample adding chamber 110, the sample solution can enter the quantitative chamber 130 and the first waste liquid chamber 140 through the first connecting microchannel 120 through rotation centrifugation, and gradually fill the first waste liquid chamber 140 and the quantitative chamber 130. The excess sample solution overflows into the second waste liquid chamber 160 through the overflow microchannel 150. Through further centrifugation, the solid impurities in the sample solution can be separated from the solution to be tested (for example, blood cells in a whole blood sample can be separated from serum (plasma)). The solid impurities are centrifugally precipitated into the first waste liquid chamber 140, and the solution to be tested remains in the quantitative chamber 130 close to the proximal end 11, thereby achieving separation and quantification of the sample solution. When detection is required, the detection mechanism can be used to detect the quantitative solution to be tested in the quantitative chamber 130.

[0049] The microfluidic chip 10 can separate and quantify impurities in the sample solution and the target solution to be tested by centrifugation only once after adding the sample solution, without excessive centrifugation operations. Therefore, the operation is simple, the waiting time is short, and the efficiency of sample processing is significantly improved.

[0050] In a specific example, the sample loading hole 111 is closer to the proximal end 11 than the connection position between the sample loading chamber 110 and the first connecting microchannel 120 , so that the sample solution can be prevented from flowing back out of the sample loading hole 111 during the centrifugal operation.

[0051] In a specific example, the sample loading chamber 110 further has a first vent hole 112, and the first vent hole 112 is closer to the proximal end 11 than the connection position between the sample loading chamber 110 and the first connecting microchannel 120. By providing the first vent hole 112, when loading the sample, the air in the sample loading chamber 110 can be discharged in a timely and effective manner to ensure smooth loading.

[0052] In a specific example, the connection between the sample loading chamber 110 and the first connecting microfluidic channel 120 is funnel-shaped, which is more conducive to introducing the sample solution in the sample loading chamber 110 into the quantitative chamber 130 via the first connecting microfluidic channel 120 .

[0053] In one embodiment, the microfluidic chip 10 further includes a quality control chamber 180. The quality control chamber 180 is connected to the second waste liquid chamber 160, and the quality control chamber 180 is farther from the proximal end 11 than the second waste liquid chamber 160. The sample solution entering the second waste liquid chamber 160 will flow in only after the quantitative chamber 130 is filled with the sample, and the excess sample solution will further flow into the quality control chamber 180 away from the proximal end 11 in the second waste liquid chamber 160. By observing whether there is liquid in the quality control chamber 180, it can be determined whether the quantitative chamber 130 is filled with the sample solution.

[0054] In a specific example, the microfluidic chip 10 further includes a second connecting microchannel 190 connected to the second waste liquid chamber 160, the second connecting microchannel 190 gradually extends from one end connected to the second waste liquid chamber 160 toward the proximal end 11, and is provided with a second vent hole 191 at the other end. By providing the second vent hole 191 on one side of the second waste liquid chamber 160 close to the proximal end 11, when the sample solution overflows into the second waste liquid chamber 160, the air in the second waste liquid chamber 160 can be discharged in time to ensure smooth overflow.

[0055] In a specific example, the microfluidic chip 10 further includes a third connecting microchannel 200, and the first waste liquid chamber 140 is connected to the quantitative chamber 130 through the third connecting microchannel 200. By providing the third connecting microchannel 200, the first waste liquid chamber 140 can be separated from the quantitative chamber 130 to prevent impurities deposited in the first waste liquid chamber 140 from entering the quantitative chamber 130.

[0056] In a specific example, the microfluidic chip 10 further includes a liquid outlet microchannel 170. One end of the liquid outlet microchannel 170 is connected to the quantitative cavity 130, and the other end has a permeation hole 171. The liquid outlet microchannel 170 is used to guide the quantitative solution to be tested in the quantitative cavity 130 from the permeation hole 171 to the detection mechanism.

[0057] Further, the liquid outlet microchannel 170 includes a capillary channel 172. One end of the capillary channel 172 is connected to the third connecting microchannel 200, and the other end is provided with a permeation hole 171. Further, the capillary channel 172 gradually extends from the end connected to the third connecting microchannel 200 in a direction close to the proximal end 11 and bends to extend away from the proximal end 11. The bending vertex position of the capillary channel 172 is closer to the proximal end 11 than the connection position of the quantitative cavity 130 and the first connecting microchannel 120. By setting the capillary flow channel 172, the capillary flow channel 172 can play the role of a "valve". When the sample solution is separated and quantified, the "valve" is closed, and the sample solution to be tested will not break through the bending apex of the capillary flow channel 172 and penetrate from the penetration hole 171; in subsequent detection, under the action of the capillary force of the capillary flow channel 172, combined with low-speed centrifugation, the solution to be tested in the quantitative cavity 130 will continue to move forward along the capillary flow channel 172 under the action of siphon, and can penetrate from the penetration hole 171 to be detected.

[0058] In a specific example, the liquid outlet microfluidic channel 170 further includes a fourth connecting microfluidic channel 173. One end of the fourth connecting microfluidic channel 173 is connected to the third connecting microfluidic channel 200, and the other end is connected to the capillary channel 172. By providing the fourth connecting microfluidic channel 173, it is easier to introduce the quantitative solution to be tested in the quantitative cavity 130 into the capillary channel 172 during detection. Preferably, the fourth connecting microfluidic channel 173 gradually extends from the end connected to the third connecting microfluidic channel 200 toward the direction close to the proximal end 11 to connect to the capillary channel 172.

[0059] During the centrifugal separation and quantification of the sample solution, since the centrifugal force is greater than the capillary force in the capillary channel 172, the sample solution will not break through the bending apex of the capillary channel 172, and the capillary channel 172 can play the role of closing the "valve". During subsequent testing, under the condition of low-speed centrifugation, the solution to be tested in the quantitative cavity 130 will continue to advance along the capillary channel 172 under the action of the capillary force, and break through the bending apex of the capillary channel 172. The "valve" opens, and under the action of siphon, the solution to be tested continues to advance and seeps through the hole 171 to the detection mechanism for detection.

[0060] The capillary channel 172 is used as a valve to control the contact reaction between the sample and the detection mechanism, which can replace the traditional delayed opening mechanism such as water-soluble membrane or valve, making the sampling detection process more stable and reliable, while simplifying the chip assembly process, which is conducive to reducing production costs.

[0061] In a specific example, each microfluidic chip 10 is provided with a separation and quantification unit 100. The microfluidic chip 10 may be in a sector-shaped structure as a whole but is not limited to it, and may be installed on a centrifugal tray or other device to implement single item detection of a sample.

[0062] Furthermore, in a specific example, the microfluidic chip 10 also has a clamping portion 12 for mounting on a centrifugal device. The clamping portion 12 is used to clamp on an external device such as a centrifugal tray, and has the functions of positioning and stabilizing assembly.

[0063] More specifically, in one example, the clamping portion 12 may be located at, but not limited to, the proximal end 11 of the microfluidic chip 10 .

[0064] like Figure 3 As shown in FIG. 1 , in a specific example, the microfluidic chip 10 includes a chip body 13 and a transparent cover film 14 covering the chip body 13. The chip body 13 and the transparent cover film 14 cooperate to form various cavity structures and flow channel structures. Specifically, the grooves of each cavity structure and flow channel structure are pre-formed on the chip body 13, such as Figure 2As shown, each hole opens on the back side of the chip body 13, while the grooves of each cavity structure and flow channel structure open on the front side of the chip body 13. Subsequently, the cavity structure and flow channel structure are packaged by covering and sealing on the front side of the chip body 11 with a transparent cover film 12 to form a complete cavity structure and flow channel structure.

[0065] The transparent cover film 14 can be but not limited to transparent tape or transparent pressure-sensitive adhesive, etc., which cooperates with the chip body 13 to form the entire microfluidic chip 10. The assembly is simple, and there is no need to use complex and expensive ultrasonic welding technology. Direct bonding is sufficient, which can significantly reduce the production cost. It is understandable that in other specific examples, the microfluidic chip 10 can also be formed by welding using a relatively expensive ultrasonic welding technology, or integrally formed using 3D printing technology.

[0066] The present invention further provides an in vitro detection system, which includes the above-mentioned microfluidic chip 10 and a detection mechanism, wherein the detection mechanism is connected to the quantitative cavity 130 through the permeation hole 171 , and the detection mechanism is used to detect the sample in the quantitative cavity 130 .

[0067] In one specific example, the detection mechanism is a dry chemical test paper. More specifically, the dry chemical test paper includes a support layer and a reaction indicator layer and a diffusion layer stacked in sequence on the support layer, the reaction indicator layer contains a reaction reagent and an indicator reagent that can react with the target substance in the sample to be tested, and the diffusion layer faces the permeation hole 171 through the injection port. It can be understood that in other specific examples, the detection mechanism is not limited to dry chemical test paper, and can also be various other test strips or reactors.

[0068] In a specific example, if Figure 2 As shown, the microfluidic chip 10 is provided with mounting grooves 15 around the permeation holes 171 of the separation and quantitative unit 100 , and the detection mechanism is embedded in each mounting groove 15 .

[0069] In a specific example, if Figure 4 , Figure 5 and Figure 6 As shown, the in vitro detection system further comprises a centrifugal tray 20 for mounting on the centrifugal device. The centrifugal tray 20 is provided with a mounting position 21 for placing the microfluidic chip 10.

[0070] More specifically, the centrifugal tray 20 has a rotating mounting portion 22 in the middle thereof. There are a plurality of mounting positions 21, and the plurality of mounting positions 21 are arranged around the rotating mounting portion 22.

[0071] Furthermore, the centrifugal tray 20 is provided with at least one observation hole for observing the state of the microfluidic chip 10 and / or the test results at the mounting position 21. For example, in the specific example shown in the figure, the centrifugal tray 20 is provided with a detection hole 23 corresponding to the detection mechanism, and a quality control hole 24 for observing the state of the quality control cavity 180.

[0072] The following Figure 1 The specific microfluidic chip and Figure 4 Taking the centrifugal tray for testing whole blood samples as an example, the separation and quantification of the sample solution and the testing process are further described in detail. A plurality of microfluidic chips 10 can be installed on the centrifugal tray 20, and a corresponding number of microfluidic chips 10 can be installed according to the specific test project requirements and sample requirements. For vacant positions, blank microfluidic chips 10 can be used to fill them to ensure the basic balance of each position of the centrifugal tray 20.

[0073] The separation and quantification process of the whole blood sample by the microfluidic chip 10 can be referred to but not limited to the following:

[0074] like Figure 7-1 As shown, a whole blood sample is added into the sample loading chamber 110 through the sample loading hole 111 , the centrifugal tray 20 is installed on a detection device with a centrifugal function, the device is turned on, and the centrifugal tray 20 is rotated.

[0075] like Figure 7-2 As shown, as the centrifugation proceeds, the whole blood sample in the sample loading chamber 110 enters the quantitative chamber 130 and the first waste liquid chamber 140 via the first connecting microchannel 120, and the excess whole blood sample enters the quality control chamber 180 and the second waste liquid chamber 160 via the overflow microchannel 150. When the whole blood sample is detected in the quality control chamber 180, it means that the quantitative chamber 13 is filled with the whole blood sample. Figure 7-2-1 As shown, since the bending apex of the capillary flow channel 172 is closer to the proximal end 11 than the top of the quantitative cavity 130, during high-speed centrifugation (such as 4000-6000rpm), the centrifugal force is greater than the capillary suction force in the capillary flow channel 172, and the whole blood sample solution will only enter the section 172a of the capillary flow channel 172, and will not break through the bending apex 172b of the capillary flow channel 172 and flow to the section 172c.

[0076] like Figure 7-3 As shown, the centrifugation process continues, and the blood cells in the whole blood sample filled in the quantitative chamber 130 are separated from the serum (plasma) and deposited in the first waste liquid chamber 140, thereby achieving the separation and quantification of the whole blood sample.

[0077] The detection process of the whole blood sample using the microfluidic chip 10 may refer to but not be limited to the following:

[0078] like Figure 8-1 and Figure 8-2 As shown, after the quantification of the whole blood sample is completed, the rotation of the centrifugal tray 20 is stopped, and the serum (plasma) quantified in the quantitative cavity 130 will continue to move along the capillary flow channel 172 under the action of the capillary force of the capillary flow channel 172, and break through the bending apex 172b of the capillary flow channel 172. Preferably, the device is turned on for low-speed centrifugation (such as 1000-2500rpm), and the serum (plasma) seeps out from the permeation hole 171 from the 172c section of the capillary flow channel 172. Under the action of siphon, the serum (plasma) in the quantitative cavity 130 is continuously discharged until it is completely emptied and detected.

[0079] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0080] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A microfluidic chip, characterized in that: A separation and quantitative unit is provided, the separation and quantitative unit comprising a sample addition chamber, a first connecting microfluidic channel, a quantitative chamber, a first waste liquid chamber, an overflow microfluidic channel and a second waste liquid chamber; the sample addition chamber has a sample addition hole; the quantitative chamber is connected to the sample addition chamber through the first connecting microfluidic channel; the first waste liquid chamber is connected to the quantitative chamber; the second waste liquid chamber is connected to the quantitative chamber through the overflow microfluidic channel; The separation quantitative unit has a proximal end close to the rotation center during centrifugation; the sample addition cavity is closer to the proximal end than the quantitative cavity; the quantitative cavity is closer to the proximal end than the first waste liquid cavity; when the quantitative cavity is filled with liquid, the excess liquid can enter the second waste liquid cavity through the overflow microchannel, and the distance between the second waste liquid cavity and the proximal end is not less than the distance between the quantitative cavity and the proximal end; The sample loading hole is closer to the proximal end than the connection position between the sample loading cavity and the first connecting microfluidic channel; The sample loading chamber further comprises a first vent hole, and the first vent hole is closer to the proximal end than the connection position between the sample loading chamber and the first connecting microfluidic channel; It also includes a third connecting microfluidic channel, and the first waste liquid chamber is connected to the quantitative chamber through the third connecting microfluidic channel; It also includes a liquid outlet microchannel, one end of which is connected to the quantitative cavity, and the other end of which has a permeation hole; The liquid outlet microchannel comprises a capillary channel, one end of the capillary channel is connected to the third connecting microchannel, and the other end is provided with the permeation hole; The capillary flow channel gradually extends from the end connected to the third connecting microchannel toward the proximal end and bends to extend away from the proximal end; the bending vertex of the capillary flow channel is closer to the proximal end than the connection position between the quantitative cavity and the first connecting microchannel; The liquid outlet microfluidic channel further includes a fourth connecting microfluidic channel, one end of the fourth connecting microfluidic channel is connected to the third connecting microfluidic channel, and the other end of the fourth connecting microfluidic channel is connected to the capillary channel; The fourth connecting microchannel gradually extends from an end connected to the third connecting microchannel toward the proximal end to connect to the capillary channel; Each of the microfluidic chips is provided with a separation and quantification unit.

2. The microfluidic chip according to claim 1, characterized in that: The connection between the sample adding cavity and the first connecting microfluidic channel is funnel-shaped.

3. The microfluidic chip according to claim 1, characterized in that: It also includes a quality control cavity, which is connected to the second waste liquid cavity, and the quality control cavity is farther away from the proximal end than the second waste liquid cavity.

4. The microfluidic chip according to claim 1, characterized in that: It also includes a second connecting microchannel connected to the second waste liquid cavity, the second connecting microchannel gradually extends from one end connected to the second waste liquid cavity toward the proximal end, and is provided with a second air hole at the other end.

5. The microfluidic chip according to claim 1, characterized in that: The microfluidic chip also has a clamping portion for mounting on a centrifugal device.

6. The microfluidic chip according to claim 5, characterized in that: The clamping portion is located at the proximal end.

7. An in vitro detection system, characterized in that: The microfluidic chip comprises the microfluidic chip as described in any one of claims 1 to 6, and further comprises a detection mechanism, wherein the detection mechanism is connected to the quantitative cavity, and the detection mechanism is used to detect the sample in the quantitative cavity.

8. The in vitro detection system according to claim 7, characterized in that: It also includes a centrifugal tray for installation on the centrifugal device, and the centrifugal tray is provided with a mounting position for placing the microfluidic chip.

9. The in vitro detection system according to claim 8, characterized in that: The middle part of the centrifugal tray is provided with a rotating mounting part, and there are a plurality of mounting positions, which are arranged around the rotating mounting part.

10. The in vitro detection system according to claim 8, characterized in that: The centrifugal tray is provided at the installation position with at least one observation hole for observing the state of the microfluidic chip and / or the detection result.

11. The in vitro detection system according to claim 7, characterized in that: The detection mechanism is a dry chemical test paper.

12. The in vitro detection system according to claim 11, characterized in that: The dry chemical test paper comprises a support layer and a reaction indicator layer and a diffusion layer sequentially stacked on the support layer. The reaction indicator layer contains a reaction reagent and an indicator reagent that can react with a target substance in a sample to be tested. The diffusion layer faces the permeation hole through an injection port.

13. The in vitro detection system according to any one of claims 7 to 12, characterized in that: The microfluidic chip is provided with mounting grooves around the permeation holes of the separation and quantitative unit, and the detection mechanism is embedded in each of the mounting grooves.

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