Centrifugal microfluidic chip and sample detection method

Abstract

The application discloses a centrifugal micro-fluidic chip and a sample detection method. The centrifugal micro-fluidic chip comprises a lysis unit, a buffer unit, a detection unit and a first mixing channel. The lysis unit is provided with a lysis cavity and a sample inlet. The buffer unit is provided with a buffer cavity. The detection unit is provided with at least one detection cavity. The first mixing channel is communicated with the lysis cavity and the buffer cavity at two ends respectively. The cross-sectional area of the first mixing channel gradually decreases along the direction of sample flow from the lysis cavity to the buffer cavity. The sample detection method is executed by using the centrifugal micro-fluidic chip. In the application, the cross-sectional area of the first mixing channel gradually decreases along the direction of sample flow from the lysis cavity to the buffer cavity. During the mixing process, the sample and the reagent are simultaneously subjected to the capillary force and the intermittent centrifugal force, and flow back and forth between the first mixing channel and the lysis cavity, so that the sample and the reagent are fully mixed, the length of the first mixing channel and the occupied space are shortened, and the overall volume of the chip is reduced.

Description

Technical Field

[0001] This invention relates to the field of microfluidic chip technology, and in particular to a centrifugal microfluidic chip and a sample detection method. Background Technology

[0002] Centrifugal microfluidic chips use centrifugal force to drive fluid flow. During the sample detection process, the sample and reagent need to be mixed. The degree of mixing of the sample and reagent directly affects the detection accuracy. In order to ensure that the sample and reagent are fully mixed, the chip in related technologies usually has a long channel for the sample and reagent to flow and mix. This results in a large space occupied by the channel and a large overall chip size, which is not conducive to the miniaturization design of the chip. Summary of the Invention

[0003] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes a centrifugal microfluidic chip that can shorten the mixing channel and reduce the overall chip size.

[0004] The present invention also proposes a sample detection method using the above-mentioned centrifugal microfluidic chip.

[0005] According to a first aspect of the present invention, a centrifugal microfluidic chip is used to allow samples and reagents to flow under centrifugal force, comprising:

[0006] A lysis unit has a lysis chamber and an inlet communicating with the lysis chamber. The inlet is used to add samples and reagents, and the lysis chamber is used for lysis of the samples and reagents.

[0007] A buffer unit having a buffer cavity for sample dilution buffering;

[0008] The first mixing channel is connected to the lysis chamber and the buffer chamber at both ends, respectively. The cross-sectional area of ​​the first mixing channel gradually decreases along the direction of sample flow from the lysis chamber to the buffer chamber, so that the sample and reagent flow back and forth between the first mixing channel and the lysis chamber under capillary force and intermittent centrifugal force.

[0009] The detection unit has at least one detection cavity for testing a sample, and the detection cavity is connected to the buffer cavity.

[0010] The centrifugal microfluidic chip according to embodiments of the present invention has at least the following beneficial effects:

[0011] In this invention, the cross-sectional area of ​​the first mixing channel gradually decreases along the direction of sample flow from the lysis chamber to the buffer chamber. During the mixing process, the sample and reagent are simultaneously subjected to capillary force and intermittent centrifugal force, and flow back and forth between the first mixing channel and the lysis chamber, so that the sample and reagent are fully mixed, shortening the length of the first mixing channel and the space occupied, and reducing the overall volume of the chip.

[0012] According to some embodiments of the present invention, the inner wall of the first mixing channel is configured as a superhydrophobic inner wall.

[0013] According to some embodiments of the present invention, the first mixing channel includes at least one mixing section, the mixing section including a temporary storage section and a first flow section and a second flow section respectively connected to both ends of the temporary storage section, the first flow section and the second flow section being bent relative to the temporary storage section.

[0014] According to some embodiments of the present invention, the pyrolysis unit, the buffer unit and the detection unit are arranged sequentially along the centrifugal direction, and both the first flow section and the second flow section have a tendency to extend along the centrifugal direction.

[0015] According to some embodiments of the present invention, one end of the first flow section within one of the mixing sections is connected to the pyrolysis chamber.

[0016] According to some embodiments of the present invention, the pyrolysis unit, the buffer unit and the detection unit are arranged sequentially along the centrifugal direction, the first mixing channel includes at least one bent portion, and along the extending direction of the first mixing channel, the bent portion has a first end near the pyrolysis unit and a second end near the buffer unit, and the bent portion extends from the second end to the first end along the centrifugal direction.

[0017] According to some embodiments of the present invention, the pyrolysis unit, the buffer unit and the detection unit are arranged sequentially along the centrifugal direction, the first mixing channel has a first connecting segment at one end near the pyrolysis chamber and a second connecting segment at one end near the buffer chamber, and the end of the second connecting segment communicating with the buffer chamber and the end of the first connecting segment communicating with the pyrolysis chamber are arranged along the centrifugal direction.

[0018] According to some embodiments of the present invention, the centrifugal microfluidic chip further includes a second mixing channel, the two ends of which are respectively connected to the buffer cavity and the detection cavity.

[0019] The sample detection method according to a second aspect of the present invention, executed using a centrifugal microfluidic chip according to a first aspect, includes:

[0020] Sample addition: The lysis chamber is preloaded with lysis reagent, the buffer chamber with amplification buffer, and the detection chamber with amplification detection solution. The sample is then added to the lysis chamber through the injection port.

[0021] Mixing: The centrifugal microfluidic chip rotates intermittently at a first rotational speed n1, causing the sample and lysis reagent to flow back and forth between the first mixing channel and the lysis chamber;

[0022] Lysis: The sample and lysis reagent are lysed within the first mixing channel and / or the lysis chamber;

[0023] Buffering: The centrifugal microfluidic chip rotates at a second rotation speed n2, causing the sample to enter the buffer chamber for dilution and buffering;

[0024] Detection: The centrifugal microfluidic chip rotates at a third rotational speed n3, allowing the sample to enter the detection chamber for detection;

[0025] Where n1 < n2 < n3.

[0026] According to some embodiments of the present invention, in the mixing step, the pyrolysis chamber and the first mixing channel are heated;

[0027] And / or, in the lysis step, the centrifugal microfluidic chip stops rotating and the lysis chamber is heated, and the sample and reagents are lysed in the lysis chamber.

[0028] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0030] Figure 1 This is a schematic diagram of one embodiment of the centrifugal microfluidic chip of the present invention;

[0031] Figure 2 for Figure 1 A schematic diagram of the structure of one embodiment of the first mixing channel;

[0032] Figure 3 for Figure 1 A schematic diagram of the structure of the second embodiment of the first mixing channel;

[0033] Figure 4 for Figure 1 A schematic diagram of the structure of the third embodiment of the first mixing channel;

[0034] Figure 5This is a schematic flowchart of an embodiment of the sample detection method of the present invention.

[0035] Figure label:

[0036] The system includes a pyrolysis unit 100, a pyrolysis chamber 110, and an injection port 120; a buffer unit 200 and a buffer chamber 210; a detection unit 300 and a detection chamber 310; a first mixing channel 400, a mixing section 410, a temporary storage section 411, a first flow section 412, a second flow section 413, a bending section 420, a first connecting section 430, and a second connecting section 440; and a second mixing channel 500. Detailed Implementation

[0037] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0038] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0039] In the description of this invention, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0040] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0041] In the description of this invention, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0042] Centrifugal microfluidic chips use centrifugal force as the primary driving force for fluid flow. They aim to integrate complex experimental procedures onto a miniaturized rotating platform. The rotation of the platform provides centrifugal force, enabling fluid flow within the microfluidic chip and facilitating integrated and automated detection. After the sample is added to the chip, it needs to be mixed and reacted with the corresponding reagents. Because the sample is in a continuous flow state during detection, to ensure thorough mixing of the sample and reagents, the chip typically has long channels for flow and mixing. This results in a large space occupied by the channels and a large overall chip volume, which does not conform to the miniaturization design concept of microfluidic chips.

[0043] Reference Figure 1 This application provides a centrifugal microfluidic chip (hereinafter referred to as the chip) that allows samples and reagents to flow under centrifugal force for analysis and detection. The centrifugal microfluidic chip includes a lysis unit 100, a buffer unit 200, and a detection unit 300. The lysis unit 100 has a lysis chamber 110 inside and an inlet 120 connected to the lysis chamber 110. Samples and reagents are added into the lysis chamber 110 through the inlet 120 and mixed and lysed within the lysis chamber 110. The buffer unit 200 has a buffer chamber 210 for diluting and buffering samples. The detection unit 300 has at least one detection chamber 310 for detecting samples. The detection unit 300 is provided with an air vent connected to the detection chamber 310 to maintain the air pressure balance inside and outside the detection chamber 310. The lysis chamber 110, buffer chamber 210 and detection chamber 310 are connected in sequence. The sample and reagent first enter the lysis chamber 110 and are lysed after mixing. The lysed sample flows to the buffer chamber 210 under the action of centrifugal force and is diluted and buffered in the buffer chamber 210. Then it continues to flow to the detection chamber 310 under the action of centrifugal force and the detection is completed in the detection chamber 310.

[0044] In this application, the lysis chamber 110 and the buffer chamber 210 are connected by a first mixing channel 400. The two ends of the first mixing channel 400 are respectively connected to the lysis chamber 110 and the buffer chamber 210. The lysed reagents and samples can enter the buffer chamber 210 through the first mixing channel 400. When the chip is driven to rotate, centrifugal force is generated. This centrifugal force points from the center of rotation of the chip to the edge of the chip. During the flow of the sample and reagents inside the chip, the centrifugal force causes them to tend to flow from the lysis chamber 110 to the buffer chamber 210 and from the buffer chamber 210 to the detection chamber 310. Furthermore, during the flow of the sample and reagents, they are simultaneously subjected to the influence of the chip... The capillary force provided by the inner wall of the cavity or channel, taking the first mixing channel 400 as an example, is greater at the position with a smaller cross-section of the first mixing channel 400. The sample and reagent flowing into the first mixing channel 400 tend to flow from the position with a smaller cross-sectional area to the position with a larger cross-sectional area under the capillary action. Since the cross-sectional area of ​​the first mixing channel 400 gradually decreases along the direction of sample flow from the lysis chamber 110 to the buffer chamber 210 in this embodiment, the sample and reagent located in the first mixing channel 400 tend to flow towards the lysis chamber 110 under the capillary action.

[0045] Furthermore, in this embodiment, the sample and reagent are simultaneously subjected to capillary force and intermittent centrifugal force, and flow back and forth between the first mixing channel 400 and the lysis chamber 110, so that the sample and reagent are fully mixed, shortening the length of the first mixing channel 400 and the space occupied, and reducing the overall volume of the chip. Specifically, when the sample and reagent flow from the lysis chamber 110 to the first mixing channel 400, they are simultaneously subjected to centrifugal force and capillary force. Under the set centrifugal force, the sample and reagent can flow from the lysis chamber 110 into the first mixing channel 400. However, when the centrifugal force is removed, the sample and reagent flow towards the lysis chamber 110 under the action of capillary force and then flow from the first mixing channel 400 into the lysis chamber 110. At this time, the sample and reagent are again subjected to the combined action of centrifugal force and capillary force and flow towards the first mixing channel 400. Therefore, the sample and reagent flow back and forth between the first mixing channel 400 and the lysis chamber 110 under the action of capillary force and intermittent centrifugal force, and are continuously mixed, so that the mixing of the sample and reagent is more thorough, and there is no need to extend the length of the first mixing channel 400, which meets the design requirements of chip miniaturization.

[0046] Understandably, the sample, reagents, and the resulting product to be detected are all in a liquid state and can flow inside the chip. In addition, the inner wall of the first mixing channel 400 is designed as a hydrophobic inner wall, which creates a large capillary force between the sample and the inner wall of the first mixing channel 400 and reduces the flow resistance of the sample. This improves the flow efficiency of the sample and reagents within the first mixing channel 400 and allows them to accurately return from the first mixing channel 400 to the lysis chamber 110.

[0047] Furthermore, in one embodiment of this application, the inner wall of the first mixing channel 400 is configured as a superhydrophobic inner wall. The superhydrophobic inner wall has excellent hydrophobic properties, enabling the sample and reagent to flow efficiently within the first mixing channel 400 using capillary force, and has high flow accuracy. It should be noted that by controlling the chip's rotation speed, the centrifugal force provided by the chip to the sample and reagent can be set. The sample and reagent will only enter the first mixing channel 400 and the lysis chamber 110 and move back and forth between them, without moving to other areas of the chip, thus giving the chip a more precise sample control capability. Under the premise of satisfying the reciprocating flow of the sample and reagent within the first mixing channel 400 and the lysis chamber 110, the difference between the actual centrifugal force and the theoretically calculated centrifugal force experienced by the sample and reagent within the first mixing channel 400 with its superhydrophobic inner wall is small, giving the chip a more precise rotation speed. In addition, the interface between the sample and the superhydrophobic inner wall of the first mixing channel 400 has sufficient capillary force, and the cross-section of the first mixing channel 400 can be set to have a relatively gentle gradient. That is, the dimensional shrinkage of the cross-section of the first mixing channel 400 from the lysis chamber 110 to the buffer chamber 210 is small, and the inner wall of the first mixing channel 400 can be smoother, which is beneficial to reducing the cross-sectional area of ​​the first mixing channel 400 and facilitating the positional distribution of the first mixing channel 400, the lysis unit 100, and the buffer unit 200.

[0048] The chip can be composed of two layers of polymer materials such as PDMS (polydimethylsiloxane). For example, the chip includes a channel layer and a substrate layer. Grooves are provided at corresponding positions on the surface of the channel layer. The channel layer and the substrate layer are connected to each other using oxygen plasma bonding or double-sided adhesive bonding, and then sealed. The grooves on the surface of the channel layer form channels or cavities after the channel layer and substrate layer are bonded together. The channel layer and substrate layer can be formed by etching, vapor deposition, injection molding, 3D printing, etc. Additionally, a superhydrophobic material can be coated into the corresponding grooves of the channel layer to form the superhydrophobic inner wall of the first hybrid channel 400.

[0049] In one specific embodiment, the superhydrophobic inner wall of the first mixing channel 400 can be achieved as follows: 1g of silica nanoparticles are added to a 50mL centrifuge tube containing 40mL of toluene, and sonicated at 300W for 30 minutes. Then, 0.6mL of a silane coupling agent such as 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDTES) is added, and the mixture is magnetically stirred at room temperature for 48 hours. The silane-modified silica nanoparticles are then washed with anhydrous ethanol. Finally, the dried silica nanoparticles are mixed with PDMS at a 2:3 ratio and added to 10mL of ethyl acetate. The mixture is sonicated at 300W for 30 minutes and magnetically stirred at room temperature for 1 hour to obtain a superhydrophobic reagent. The superhydrophobic reagent is then added to the first mixing channel 400, and after drying, a superhydrophobic coating is formed on the inner surface of the first mixing channel 400, giving the first mixing channel 400 a superhydrophobic inner wall.

[0050] Furthermore, it should be emphasized that centrifugal microfluidic chips require high fluid control capabilities to ensure that samples can flow precisely into the corresponding cavities for reaction. Traditional technologies apply active fluid control strategies to centrifugal microfluidic chips, such as adding iron wax microvalves, ball valves, and power pumps, which makes the control of the microfluidic chip more complex and increases the difficulty of operation. In this application, fluid control is assisted by changes in capillary force within the first mixing channel 400, eliminating the need for additional control measures. This satisfies the diverse integrated functional requirements of microfluidic chips and reduces their complexity and operational difficulty.

[0051] Reference Figure 2 The first mixing channel 400 includes at least one mixing section 410. The mixing section 410 includes a temporary storage section 411 and a first flow section 412 and a second flow section 413 respectively connected to the two ends of the temporary storage section 411, providing a mixing space for the sample and reagent. One of the first flow section 412 and the second flow section 413 is close to and communicates with the lysis chamber 110, and the other is close to and communicates with the buffer chamber 210. Both the first flow section 412 and the second flow section 413 are bent relative to the temporary storage section 411. Therefore, the mixing section 410 has a curved area, and can provide appropriate resistance to the sample and reagent when the sample and reagent flow into the first mixing channel 400, slowing down the flow rate of the sample and reagent, preventing the sample and reagent from directly entering the buffer chamber 210 after entering the first mixing channel 400 under the action of centrifugal force, so that the sample and reagent are completely transferred from the lysis chamber 110 to the first mixing channel 400 during the stage when centrifugal force is applied, and transferred from the first mixing channel 400 to the lysis chamber 110 during the stage when centrifugal force is removed.

[0052] The lysis unit 100, buffer unit 200, and detection unit 300 are arranged sequentially along the centrifugal direction, which refers to the direction of the centrifugal force provided when the chip rotates. It should be noted that arranging the lysis unit 100, buffer unit 200, and detection unit 300 along the centrifugal direction ensures that the flow path of the sample and reagent during the detection process is the same as the direction of the centrifugal force. This allows the sample and reagent to pass through the lysis unit 100, buffer unit 200, and detection unit 300 sequentially under the action of centrifugal force, completing lysis, dilution buffering, and detection in that order. The statement that the lysis unit 100, buffer unit 200, and detection unit 300 are arranged along the centrifugal direction means that the lysis unit 100, buffer unit 200, and detection unit 300 have a tendency to be arranged along the centrifugal direction; it does not strictly limit the arrangement trajectory of each unit to be the same as the centrifugal direction.

[0053] In one embodiment, the first flow section 412 and the second flow section 413 are both designed to extend in the centrifugal direction. The centrifugal forces acting on the samples in the first flow section 412 and the second flow section 413 are in the same direction, and at the same time, opposite forces are applied to the samples in the temporary storage section 411. The centrifugal forces acting on the samples in the first flow section 412 and the second flow section 413 cancel each other out. Although the samples in the temporary storage section 411 are still subject to centrifugal force, the inner wall of the temporary storage section 411 provides a certain resistance to the flow of the samples because the extension direction of the temporary storage section 411 is at a certain angle to the centrifugal direction. This ensures that the samples remain in the first mixing channel 400 under the action of centrifugal force and capillary force, and do not directly enter the buffer chamber 210. After the centrifugal force is removed, the samples return to the lysis chamber 110 from the first mixing channel 400.

[0054] Furthermore, one end of the first flow section 412 in one of the mixing sections 410 is connected to the pyrolysis chamber 110. That is, the first flow section 412 is located at the end of the temporary storage section 411 near the pyrolysis chamber 110, and the second flow section 413 is located at the end of the temporary storage section 411 near the buffer chamber 210. One end of the first flow section 412 is directly connected to the pyrolysis unit 100 and communicates with the pyrolysis chamber 110. Since the lysis unit 100, buffer unit 200 and detection unit 300 tend to be arranged along the centrifugal direction, and the first flow section 412 extends along the centrifugal direction, the sample inlet of the first flow section 412 connected to the lysis unit 100 is connected to the lysis chamber 110, and the sample outlet is connected to the temporary storage section 411. The sample discharged from the lysis chamber 110 flows directly from the first flow section 412 through the temporary storage section 411 to the second flow section 413 under the action of centrifugal force and capillary force. The centrifugal forces of the first flow section 412 and the second flow section 413 cancel each other out, so that the sample can slow down its flow rate in the early stage of entering the first mixing channel 400 and can stay in the first mixing channel 400.

[0055] Understandably, when the first mixing channel 400 includes multiple mixing sections 410, it can provide more sufficient flow space for the mixing of samples and reagents, making the mixing of samples and reagents more uniform. The mixing sections 410 are directly or indirectly connected to each other. Along the direction from the lysis chamber 110 to the buffer chamber 210, the second flow section 413 of the previous mixing section 410 is connected to the first flow section 412 of the next mixing section 410.

[0056] In one embodiment, refer to Figure 3 The first mixing channel 400 includes at least one bend 420. Along the extending direction of the first mixing channel 400, the bend 420 has a first end near the lysis unit 100 and a second end near the buffer unit 200. The bend 420 extends from the second end to the first end in the centrifugal direction. Since the flow tendency of the sample and reagent when simultaneously subjected to centrifugal force and capillary force is to move away from the lysis unit 100 and towards the buffer unit 200, the flow direction of the sample and reagent in the bend 420 is opposite to the centrifugal direction. The speed of the sample and reagent flowing to the bend 420 is slowed down, allowing the sample and reagent sufficient time to flow and mix in the first mixing channel 400, and to remain in the first mixing channel 400 under the combined action of centrifugal force and capillary force, and to return to the lysis chamber 110 after the centrifugal force is removed.

[0057] Additionally, refer to Figure 4 The first mixing channel 400 has a first connecting section 430 at one end near the lysis chamber 110 and a second connecting section 440 at one end near the buffer chamber 210. The end of the second connecting section 440 that connects to the buffer chamber 210 and the end of the first connecting section 430 that connects to the lysis chamber 110 are arranged along the centrifugal direction. The end of the first mixing channel 400 that connects to the lysis chamber 110 is defined as the inlet end, and the end that connects to the buffer chamber 210 is defined as the outlet end. The outlet end is always located on the side of the inlet end facing the centrifugal direction, which conforms to the overall arrangement trend of the lysis unit 100, the buffer unit 200 and the detection unit 300, and enables the sample and reagent to be quickly transferred from the end of the first mixing channel 400 to the buffer chamber 210 under the action of the corresponding centrifugal force.

[0058] The chip also includes a second mixing channel 500, whose two ends are connected to the buffer chamber 210 and the detection chamber 310, respectively. After the sample flows out of the buffer chamber 210, it enters the detection chamber 310 through the second mixing channel 500 for detection. The second mixing channel 500 increases the time and space for sample dilution buffering, resulting in more uniform sample dilution. Understandably, the second mixing channel 500 can be configured in a curved shape to increase the sample flow path, further improving the uniformity of sample dilution and detection accuracy.

[0059] The detection unit 300 is provided with multiple detection chambers 310, each of which is connected to the buffer chamber 210. Different types of detection reagents can be pre-placed in the multiple detection chambers 310 to perform different types of detection on the sample, or to serve as a control group to obtain the influence of different parameters on the detection results. Of course, the same detection reagent can also be placed in the multiple detection chambers 310 to reduce the impact of detection failure in a single detection chamber 310 on the detection results.

[0060] Reference Figure 5 This application also provides a sample detection method, which is executed using the above-mentioned centrifugal microfluidic chip, including the following steps:

[0061] Adding samples: such as Figure 5 In Figure (a), lysis reagent is pre-loaded into lysis chamber 110, amplification buffer is pre-loaded into buffer chamber 210, and detection reagent is pre-loaded into detection chamber 310. Sample is then added into lysis chamber 110 through injection port 120; mixing: as shown... Figure 5 In Figure (b), the control chip rotates intermittently at a first rotational speed n1, providing centrifugal force to the sample and lysis reagent, causing the sample and lysis reagent to flow back and forth between the first mixing channel 400 and the lysis chamber 110, and to be thoroughly mixed; lysis: as shown Figure 5 In Figure (c), the sample and lysis reagent are lysed within the first mixing channel 400 and / or lysis chamber 110; buffer: as shown Figure 5 In Figure (d), the chip rotation speed is increased to a second rotation speed n2. At this point, the centrifugal force increases, and the mixed sample and lysis reagent enter buffer chamber 210 for dilution buffering under the action of amplification buffer; detection: as shown... Figure 5 In Figure (e), the chip rotation speed is further increased to a third rotation speed n3. At this time, the centrifugal force is further increased, and the sample enters the detection chamber 310 from the buffer chamber 210 for detection. The above states n1 < n2 < n3.

[0062] It should be noted that by the reciprocating movement of the sample and lysis reagent between the first mixing channel 400 and the lysis chamber 110, the sample and lysis reagent can be thoroughly mixed; during the mixing process, there is a possibility of a lysis reaction occurring between the sample and the lysis reagent. Therefore, the mixing and lysis of the sample and the lysis reagent can be carried out simultaneously, giving the chip a high detection efficiency.

[0063] Furthermore, to accelerate the lysis process and provide a suitable lysis environment for the sample, in some embodiments, the lysis chamber 110 and the first mixing channel 400 are heated during the mixing step, so that the sample and lysis reagent are continuously heated during the reciprocating flow, thereby accelerating the mixing and lysis of the sample and reagent. Alternatively, after mixing is completed, the control chip stops rotating, at which point the sample and lysis reagent return to the lysis chamber 110, and the lysis chamber 110 is heated, so that the sample and lysis reagent complete lysis within the lysis chamber 110.

[0064] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments, and various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A sample detection method, characterized in that, The process employs a centrifugal microfluidic chip, which enables the flow of samples and reagents under centrifugal force. The centrifugal microfluidic chip comprises: A lysis unit has a lysis chamber and an inlet communicating with the lysis chamber. The inlet is used to add samples and reagents, and the lysis chamber is used for lysis of the samples and reagents. A buffer unit having a buffer cavity for sample dilution buffering; The first mixing channel is connected to the lysis chamber and the buffer chamber at both ends, respectively. The cross-sectional area of ​​the first mixing channel gradually decreases along the direction of sample flow from the lysis chamber to the buffer chamber, so that the sample and reagent flow back and forth between the first mixing channel and the lysis chamber under capillary force and intermittent centrifugal force. The detection unit has at least one detection cavity for detecting a sample, and the detection cavity is connected to the buffer cavity. Sample testing methods include: Sample addition: The lysis chamber is preloaded with lysis reagent, the buffer chamber with amplification buffer, and the detection chamber with amplification detection solution. The sample is then added to the lysis chamber through the injection port. Mixing: The centrifugal microfluidic chip rotates intermittently at a first rotational speed n1, causing the sample and lysis reagent to flow back and forth between the first mixing channel and the lysis chamber; Lysis: The sample and lysis reagent are lysed within the first mixing channel and / or the lysis chamber; Buffering: The centrifugal microfluidic chip rotates at a second rotation speed n2, causing the sample to enter the buffer chamber for dilution and buffering; Detection: The centrifugal microfluidic chip rotates at a third rotational speed n3, allowing the sample to enter the detection chamber for detection; Where n1 < n2 < n3.

2. The sample detection method according to claim 1, characterized in that, The inner wall of the first mixing channel is configured as a superhydrophobic inner wall.

3. The sample detection method according to claim 1, characterized in that, The first mixing channel includes at least one mixing section, which includes a temporary storage section and a first flow section and a second flow section respectively connected to both ends of the temporary storage section. Both the first flow section and the second flow section are bent relative to the temporary storage section.

4. The sample detection method according to claim 3, characterized in that, The pyrolysis unit, the buffer unit, and the detection unit are arranged sequentially along the centrifugal direction, and both the first flow section and the second flow section have a tendency to extend along the centrifugal direction.

5. The sample detection method according to claim 4, characterized in that, One end of the first flow section within one of the mixing sections is connected to the pyrolysis chamber.

6. The sample detection method according to claim 1, characterized in that, The pyrolysis unit, the buffer unit, and the detection unit are arranged sequentially along the centrifugal direction. The first mixing channel includes at least one bent portion. Along the extension direction of the first mixing channel, the bent portion has a first end near the pyrolysis unit and a second end near the buffer unit. The bent portion extends from the second end to the first end along the centrifugal direction.

7. The sample detection method according to claim 1, characterized in that, The pyrolysis unit, the buffer unit, and the detection unit are arranged sequentially along the centrifugal direction. The first mixing channel has a first connecting segment at the end near the pyrolysis chamber and a second connecting segment at the end near the buffer chamber. The end of the second connecting segment that connects to the buffer chamber and the end of the first connecting segment that connects to the pyrolysis chamber are arranged along the centrifugal direction.

8. The sample detection method according to claim 1, characterized in that, The centrifugal microfluidic chip also includes a second mixing channel, the two ends of which are respectively connected to the buffer cavity and the detection cavity.

9. The sample detection method according to claim 1, characterized in that, In the mixing step, the pyrolysis chamber and the first mixing channel are heated; And / or, in the lysis step, the centrifugal microfluidic chip stops rotating and the lysis chamber is heated, and the sample and reagents are lysed in the lysis chamber.

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