A digital PCR droplet generation device and method

Abstract

The present invention discloses a digital PCR droplet generation device and a droplet generation method, wherein the droplet generation device includes a chip body, the chip body has a droplet generation chamber and a droplet storage chamber connected to the droplet generation chamber, and also includes a liquid absorbing liquid with a liquid absorbing function, the liquid absorbing liquid is used in conjunction with the chip body to drive the droplets from the droplet generation chamber to the droplet storage chamber. After the droplets begin to be generated in the droplet generation chamber or the droplet generation is completed, the liquid absorbing liquid with a liquid absorbing function is used to absorb the liquid, so as to promote the droplets in the droplet generation chamber to gradually transfer to the droplet storage chamber, thereby gradually realizing the tiling process in the droplet storage chamber. This is completely different from the traditional solution of using a negative pressure device to promote the droplets to enter and complete the tiling in the droplet storage chamber. Its implementation method is simple and effective, does not occupy instrument resources, significantly reduces costs, and greatly improves detection efficiency.

Description

Technical Field

[0001] The invention relates to a digital PCR droplet generating device and a generating method. Background Art

[0002] With the transformation of medical models and the continuous development of personalized medicine, the medical testing community is in urgent need of fast and accurate testing methods, and molecular testing has unique advantages.

[0003] At present, molecular detection technologies mainly include nucleic acid molecular hybridization, polymerase chain reaction (PCR) and biochip technology. Molecular detection products are mainly used in the detection of clinical departments such as tumors, infections, genetics, and prenatal screening, as well as physical examination centers, technical service centers, third-party testing agencies and the rapid microbial detection market.

[0004] As an important technical means of molecular detection, PCR can qualitatively and quantitatively detect target nucleic acid molecules. Against the background of increasing application demands such as low-abundance detection and rare mutation detection, digital PCR, as a nucleic acid molecule absolute quantification technology, distributes a fluorescent quantitative PCR reaction system into a large number of tiny reactors. Each microreactor contains one or more copies of the target nucleic acid molecule for "single-molecule template PCR amplification". After the amplification, the number of copies of the target gene in the original sample is calculated by the number of positive reaction units and statistical methods. Digital PCR can accurately perform absolute quantitative detection without relying on controls and standard curves.

[0005] At present, blood routine, cytology, pathology and immunology testing methods are all developing in the direction of automation, integration and standardization. However, due to the complexity of molecular detection technology itself, there are many difficult-to-solve technical problems in the process of automated realization from sample to result. As far as the micro-droplet observation of digital PCR detectors is concerned, if droplet array microscopy imaging is used, the generated droplets need to be transferred and tiled. If the droplets overlap with each other, it will be inconvenient for observation and analysis. The traditional way to promote droplet transfer and tiling is to use some peripheral driving components or driving structures such as negative pressure pumps to generate negative pressure or positive pressure. The structure and control method are relatively complex, and additional instrument resources are required. It also requires additional operation time, and the detection efficiency is relatively low. Summary of the invention

[0006] The purpose of the present invention is to overcome the defects of the prior art and provide a digital PCR droplet generating device so as to quickly and effectively promote the flattening of droplets and improve the detection efficiency.

[0007] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a digital PCR droplet generation device, including a chip body, the chip body having a droplet generation chamber and a droplet storage chamber connected to the droplet generation chamber, and also including a liquid absorbing liquid with a liquid absorbing function, the liquid absorbing liquid is used in conjunction with the chip body to drive the droplets to move from the droplet generation chamber to the droplet storage chamber.

[0008] According to some preferred solutions of the present invention, the chip body further comprises a liquid drainage cavity communicated with the liquid drop storage cavity, and the liquid absorber can be inserted in the liquid drainage cavity.

[0009] Furthermore, the liquid absorbing device can be detachably arranged on the chip body, or the liquid absorbing device can be inserted into the liquid discharge cavity separately from the chip body.

[0010] According to some preferred solutions of the present invention, the chip body has a drainage tube extending vertically upward, and the lumen of the drainage tube forms the drainage cavity.

[0011] As a specific implementation, the bottom of the liquid discharge cavity has a liquid discharge port connected to the liquid drop storage cavity, and the diameter of the liquid absorbing bottom end portion is larger than the aperture of the liquid discharge port.

[0012] According to some preferred solutions of the present invention, when the liquid absorbing body cooperates with the chip body, the liquid absorbing body is upright inserted into the liquid discharge cavity along a vertical direction.

[0013] According to some preferred embodiments of the present invention, the liquid absorbing body at least comprises a main body that can be inserted into the liquid discharge cavity, and the lower part of the main body also has a root extending downward, and the cross-sectional size of the root is smaller than the cross-sectional size of the main body.

[0014] Furthermore, the cross-sectional area of ​​the root is 0.25 to 1 mm 2 .

[0015] Furthermore, the length of the root is 1 to 8 mm.

[0016] According to some preferred embodiments of the present invention, the liquid absorbent includes a main body that can be inserted into the liquid drainage cavity, and a head located above the main body, and the head is exposed outside the liquid drainage cavity.

[0017] Furthermore, the main body is in the shape of a frustum that is larger at the top and smaller at the bottom.

[0018] As a specific implementation, the head is in a frustum shape, and the diameter of the head is larger than the caliber of the drainage cavity.

[0019] According to some preferred solutions of the present invention, a clamping piece for facilitating clamping is fixedly provided on the head.

[0020] As a specific implementation, the clamping member is a cap body fixedly buckled on the head.

[0021] According to some preferred solutions of the present invention, the liquid-absorbing material is made of a material having a capillary effect.

[0022] According to some preferred embodiments of the present invention, the liquid-absorbing material has a porous structure or a fibrous structure material.

[0023] According to some preferred embodiments of the present invention, the material for absorbing liquid is selected from capillary glass, activated carbon, wood, cloth, and paper material.

[0024] According to some preferred embodiments of the present invention, the absorbent liquid is an absorbent liquid capable of absorbing a volume of liquid in the droplet storage chamber.

[0025] According to some preferred embodiments of the present invention, the chip body has a liquid inlet tube extending vertically upward, the lumen of the liquid inlet tube forms the droplet generation chamber, and the bottom of the droplet generation chamber has a liquid inlet port connected to the droplet storage chamber.

[0026] Furthermore, the bottom wall of the droplet generation chamber is arranged to extend obliquely toward the liquid inlet.

[0027] According to some preferred embodiments of the present invention, the chip body has a liquid inlet and a liquid outlet, the droplets in the droplet generation chamber enter the droplet storage chamber through the liquid inlet, and the oil phase in the droplet generation chamber is absorbed by the liquid absorption liquid through the liquid outlet.

[0028] Furthermore, the chip body also includes a first channel connecting the liquid inlet with the droplet storage chamber and a second channel connecting the liquid discharge port with the droplet storage chamber, wherein the first channel is connected to the droplet storage chamber at an end, and the second channel is connected to the droplet storage chamber at an end, wherein the first channel, the second channel and the bottom surface of the droplet storage chamber are located at the same height.

[0029] Furthermore, the droplet storage chamber has a first communication port connected to the first channel and a second communication port connected to the second channel. The droplet storage chamber is a polygon with a first inner angle and a second inner angle. The first communication port is arranged on the first inner angle, and the second communication port is arranged on the second inner angle. The angles of the first inner angle and the second inner angle are 10° to 120°.

[0030] As a preferred embodiment, the first inner angle and the second inner angle are diagonally opposite to each other.

[0031] According to some preferred solutions of the present invention, a plurality of support columns are arranged at intervals in the droplet storage chamber, and the support columns are supported between the bottom surface and the top surface of the droplet storage chamber along the thickness direction of the chip body.

[0032] The present invention also provides a digital PCR droplet generation method, including a droplet generation step and a droplet transfer step. In the droplet transfer step, an aspirator with a liquid aspiration function is used to aspirate the oil phase to promote the movement of the droplets.

[0033] According to some preferred embodiments of the present invention, based on the above-mentioned digital PCR droplet generating device.

[0034] According to some preferred embodiments of the present invention, the method further includes heating the liquid in the chip body to accelerate the movement of the liquid droplets.

[0035] Furthermore, the bottom of the chip body is heated to control the temperature of the liquid in the chip body to be maintained at 30-90°C.

[0036] Furthermore, the chip body has a drainage cavity connected to the droplet storage cavity, and the heating temperature of the chip body increases as the liquid level height difference between the drainage cavity and the droplet generation cavity decreases.

[0037] According to some preferred embodiments of the present invention, the liquid aspirator is used to transfer the droplets in the droplet generation chamber to the droplet storage chamber.

[0038] Further, after the droplets begin to form, or after the droplets are generated, the liquid absorbing device absorbs the oil phase.

[0039] Furthermore, the chip body has a liquid discharge cavity connected to the liquid droplet storage cavity, and after the droplets are generated in the droplet generation cavity, the liquid absorption liquid is inserted into the liquid discharge cavity to absorb the oil phase.

[0040] According to some preferred solutions of the present invention, a robotic arm is used to vertically insert the liquid absorbing liquid into the liquid discharging cavity.

[0041] According to some preferred embodiments of the present invention, the droplet generation step comprises:

[0042] (1) Filling the droplet generation chamber and the droplet storage chamber of the chip body with an oil phase;

[0043] (2) Injecting an aqueous phase into the droplet generation chamber to form droplets in the droplet generation chamber.

[0044] Furthermore, in the step (2), a water phase is injected into the droplet storage chamber using a microchannel, and the microchannel is vibrated while injecting the water phase, so that droplets are formed in the droplet generation chamber.

[0045] According to the present invention, the "oil phase" and "water phase" have the general meaning in the art and are not particularly limited. The density of the oil phase is usually lower than that of the water phase.

[0046] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art: the digital PCR droplet generation device of the present invention, wherein after the droplet generation starts or the droplet generation is completed in the droplet generation chamber, a liquid suction device with a liquid suction function is used to absorb the liquid, so as to promote the droplets in the droplet generation chamber to gradually transfer to the droplet storage chamber, thereby gradually realizing the tiling process in the droplet storage chamber. The present invention directly uses the liquid suction device to absorb the liquid to promote the transfer of the droplets, thereby promoting the droplets to complete tiling in the droplet storage chamber, which is completely different from the traditional solution of using a negative pressure device to promote the droplets to enter and complete tiling in the droplet storage chamber, avoiding the use of too many pressure driving devices or complex structures to cause the complication of the overall droplet generation equipment. The droplet generation device and droplet generation method of the present invention are simple and effective in implementation, do not occupy instrument resources, thereby saving the overall operation time of the instrument for the experiment, significantly reducing costs, and greatly improving detection efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Attached Figure 1 Schematic diagram of the overall structure of the droplet generating device of Example 1 of the present invention;

[0048] Attached Figure 2 is a longitudinal cross-sectional view of the droplet generating device of Example 1;

[0049] Attached Figure 3 For the attachment Figure 2 AA-direction cross-sectional structural diagram;

[0050] Attached Figure 4 A bottom view of a chip body chip substrate in the droplet generation device of Example 1;

[0051] Attached Figure 5 A top view of a droplet generating device according to Embodiment 2 of the present invention;

[0052] Attached Figure 6 For the attachment Figure 5 Schematic diagram of the cross-sectional structure in the middle BB direction;

[0053] Attached Figure 7 For the attachment Figure 5 Schematic diagram of the cross-sectional structure in CC direction;

[0054] Attached Figure 8 Schematic diagram of the principle of droplet flat transfer in the chip body;

[0055] Attached Fig. 9 This is a schematic diagram of the overall structure of the chip body used in Example 3 of the present invention;

[0056] Attached Fig.10 is a longitudinal cross-sectional view of the chip body of Example 3;

[0057] Attached Fig.11 A structural diagram of a chip substrate in a chip body used in Embodiment 4 of the present invention;

[0058] Attached Fig.12 It is a top view of the chip body in Example 4;

[0059] Among them: 1. chip body; 1a. chip substrate; 1b. chip cover; 2. liquid inlet pipe; 3. liquid discharge pipe; 4. droplet generation chamber; 5. liquid inlet port; 6. droplet storage chamber; 61. first channel; 62. second channel; 63. first connecting port; 64. second connecting port; 65. support column; 7. liquid discharge chamber; 8. liquid discharge port; 9. liquid suction; 9a. main body; 9b. head; 9c. cap body; 9d. root. DETAILED DESCRIPTION

[0060] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0061] Example 1

[0062] See also Figures 1 to 4 As shown, a digital PCR droplet generation device includes a chip body 1, the chip body 1 has a droplet generation chamber 4 and a droplet storage chamber 6 connected to the droplet generation chamber 4, droplet generation is completed in the droplet generation chamber 4, and the generated droplets are transferred to the droplet storage chamber 6 for flattening and detection. The droplet generation device also includes an aspirating body 9 with a liquid aspirating function, and the aspirating body 9 is used in conjunction with the chip body 1 to drive the droplets to transfer from the droplet generation chamber 4 to the droplet storage chamber 6.

[0063] Specifically, see Figures 1 to 4 As shown, the chip body 1 also has a drainage cavity 7 connected to the droplet storage cavity 6. The liquid absorbing liquid 9 can be inserted in the drainage cavity 7 to absorb liquid and promote the droplets generated in the droplet generation cavity 4 to be transferred to the droplet storage cavity 6 and gradually spread.

[0064] In this embodiment, the chip body 1 has a liquid inlet tube 2 extending vertically upward and a liquid discharge tube 3 extending vertically upward. The lumen of the liquid inlet tube 2 forms a droplet generation chamber 4, and the bottom of the liquid inlet tube 2 has a liquid inlet 5 connected to the droplet storage chamber 6. The bottom wall of the droplet generation chamber 4 is arranged to extend obliquely toward the liquid inlet 5, so that the droplets generated in the droplet generation chamber 4 move toward the liquid inlet 5 one by one and gradually enter the droplet storage chamber 6. The lumen of the liquid discharge tube 3 forms a liquid discharge chamber 7, and the bottom of the liquid discharge tube 3 has a liquid discharge port 8 connected to the droplet storage chamber 6. The oil phase in the droplet storage chamber 6 is absorbed by the absorption liquid 9 through the liquid discharge port 8, thereby driving the droplets in the droplet generation chamber 4 to enter the droplet storage chamber 6 through the liquid inlet 5, thereby promoting the realization of the droplet paving process.

[0065] The liquid absorbing member 9 can be detachably connected to the chip body 1, or can be detachably inserted into the liquid discharge cavity 7 relative to the chip body 1 in the manner of this embodiment. The diameter of the bottom end of the liquid absorbing member 9 is preferably larger than the diameter of the liquid discharge port 8, so that the liquid absorbing member 9 is only inserted into the liquid discharge cavity 7 to absorb the oil phase.

[0066] Optimally, when the wicking liquid 9 cooperates with the chip body 1 , the wicking liquid 9 is inserted upright in the liquid discharge cavity 7 along the vertical direction.

[0067] See also Figure 3 As shown, the absorbent 9 includes a main body 9a that can be inserted into the drainage cavity 7, and a head 9b located above the main body 9a, and the head 9b is exposed outside the drainage cavity 7 to facilitate the absorption liquid 9 to be inserted into the drainage cavity 7 or to be taken out of the drainage cavity 7.

[0068] Furthermore, the main body 9a is configured to be a cone-shaped body with a larger top and a smaller bottom, and the head 9b is a truncated cone-shaped body with a diameter larger than the caliber of the drainage cavity 7 to ensure that the head 9b is always exposed outside the drainage cavity 7. A clamping member for easy clamping is also fixedly provided on the head 9b, so that a clamping member such as a mechanical arm can clamp and fix the absorbent liquid 9 automatically into the drainage cavity 7 or take out the absorbent liquid 9 from the drainage cavity 7. In this embodiment, the clamping member is a cap body 9c fixedly buckled on the head 9a. The cap body 9c is preferably made of a material with a certain strength.

[0069] The liquid absorbing part of the liquid absorbing body 9, that is, the main body 9a and the head 9b are integrally formed, and the whole is made of a material with capillary action. The capillary material is a single or composite material with strong capillary action, including but not limited to porous structure, fiber structure materials such as capillary glass, activated carbon, wood, cloth, paper materials, etc.

[0070] The capillary material of the absorbent 9 is preferably a paper material. When the absorbent 9 is made of paper material, the following steps can be followed: first, the pulp is made into a soft sheet-like single-layer material through a reasonable paper fiber length ratio, and then the material is cut to a suitable width, and it is rolled into a cylindrical object through automated equipment, and the object is placed in a plastic cap body 9c with structural strength for easy storage and grasping. When in use, a robotic arm is used to place the cylinder into the drainage chamber 7 to achieve automatic flattening of droplets. The material has the characteristics of easy processing and low cost. The pore density of the cylindrical object of pulp determines the density of the absorbent.

[0071] The capillary material for the liquid absorbing 9 can also be selected from a mixture of one or more materials, such as compressed wood chips, capillary fiber bundles, etc. Specifically, the wood chips are ground into micron-sized fragments, and then the two are compressed into a cylindrical entity through a ratio with gypsum; capillary fiber bundles can also be used, and a circle of hard material with pores is wrapped around the outside to reinforce the fiber bundle. At this time, the fiber bundle can absorb liquid from the side or both ends, or only from the two ends.

[0072] Of course, the absorbing liquid 9 does not necessarily need to be made into a cylindrical shape, it only needs to ensure that it can be inserted into the liquid discharge cavity 7. During manufacturing, it should be ensured that the volume of liquid that the absorbing liquid 9 can absorb is not less than the volume of the droplet storage cavity 6.

[0073] See also Figure 4 As shown, the chip body 1 also includes a first channel 61 that connects the liquid inlet 5 with the droplet storage chamber 6, and a second channel 62 that connects the liquid discharge port 8 with the droplet storage chamber 6, wherein the first channel 61 is connected to the droplet storage chamber 6 at the end, and the second channel 62 is also connected to the droplet storage chamber 6 at the end, and the first channel 61, the second channel 62 and the bottom surface of the droplet storage chamber 6 are located at the same height. Specifically, the droplet storage chamber 6 has a first connecting port 63 connected to the first channel 61, and a second connecting port 64 connected to the second channel 62. The droplet storage chamber 6 is a polygon with a first inner angle and a second inner angle. The first connecting port 63 is arranged on the first inner angle, and the second connecting port 64 is arranged on the second inner angle. The first inner angle and the second inner angle are preferably arranged diagonally, and the angle between the first inner angle and the second inner angle is 10° to 120°, so that the droplets gradually spread out evenly in a fan-shaped manner after entering the droplet storage chamber 6.

[0074] In this embodiment, the cross section of the droplet storage chamber 6 is set to be a square, and the first communication opening 63 and the second communication opening 64 are on a pair of diagonals, such as Figure 4 As shown, the other inner angles are all configured with arc inner chamfers, which is beneficial for the droplets to maintain good stability in the droplet storage chamber 1.

[0075] As shown in the drawings, the chip body 1 is mainly formed by stacking a chip cover plate 1b and a chip substrate 1a in the thickness direction, wherein the chip cover plate 1b is a flat plate, and a groove is provided on the chip substrate 1a, and the flat plate and the groove are stacked and pressed to form a droplet storage chamber 6, a first channel 61 and a second channel 62. In this embodiment, the groove opening faces downward, and the chip substrate 1a is located above the chip cover plate 1b, and the chip cover plate 1b is a transparent glass plate, a transparent PC plate, a transparent acrylic plate, a COP transparent plate or a black non-reflective plate made of non-reflective materials such as POM, PP, etc. The chip substrate 1a and the chip cover plate 1b can be welded to a seal by gluing or ultrasonic or hot pressing bonding process, and the edge between the two must maintain absolute sealing.

[0076] See also Figure 4 As shown, a plurality of support columns 65 are arranged at intervals in the droplet storage chamber 6, and each support column 65 is supported between the bottom surface and the top surface of the droplet storage chamber 6 along the thickness direction of the chip body 1, so that the overall height of the droplet storage chamber 6 can be kept in good consistency.

[0077] In this embodiment, the droplet storage chambers 6 are provided with four groups arranged in sequence along the length direction of the chip body 1, and correspondingly, the liquid inlet pipes 2 and the liquid discharge pipes 3 are also provided with four groups.

[0078] The present invention also provides a droplet generation method using the above-mentioned digital PCR droplet generation device, which includes a droplet generation step and a droplet transfer step. In the droplet transfer step, an aspirating liquid 9 with a liquid aspiration function is used to absorb the oil phase to promote the movement of droplets, so that they move from the droplet generation chamber 4 to the droplet storage chamber 6, thereby promoting the droplets to gradually spread out in the droplet storage chamber 6.

[0079] The droplet generation step can be specifically implemented according to the following steps: first, the droplet generation chamber 4 and the droplet storage chamber 6 of the chip body 1 are filled with an oil phase; then, a water phase is injected below the liquid surface of the oil phase in the droplet generation chamber 4, so that droplets are formed in the droplet generation chamber 4. Specifically, a microchannel can be used to inject the water phase, and the microchannel can be vibrated during the injection to form droplets.

[0080] After the droplets begin to form, or after the droplet generation is completed, the absorbing liquid 9 absorbs the oil phase, and the droplets are transferred from the droplet generation chamber 4 to the droplet storage chamber 6. Preferably, after the droplet generation in the droplet generation chamber 4 is completed, the absorbing liquid 9 is inserted into the liquid discharge chamber 7 in the vertical direction by the mechanical arm, and is left to stand for several seconds, waiting for the absorbing liquid 9 to absorb the oil phase, so that the liquid in the chip body 1 moves toward the liquid discharge port 8, so that the droplets in the droplet generation chamber 4 are gradually transferred to the droplet storage chamber 6 through the liquid inlet 5, and gradually spread in the droplet storage chamber 6.

[0081] Example 2

[0082] See also Figures 5 to 7 The digital PCR droplet generation device shown in the figure is mainly different from the embodiment 1 in that the lower part of the main body 9a of the liquid absorbing liquid 9 also has a root 9d extending downward, and the cross-sectional size of the root 9d is smaller than the cross-sectional size of the main body 9a, so as to form a cross-sectional tightening structure at the bottom of the liquid absorbing liquid 9, so that the liquid can be sucked out from the liquid discharge port 8, and the droplets are transferred to the droplet storage chamber 6. The cross-sectional area of ​​the root 9d can determine the magnitude of the negative pressure generated, and then determine the speed of the liquid flow. Preferably, the cross-sectional area of ​​the root 9d is preferably 0.25 to 1 mm 2 , and its length is preferably 1 to 8 mm, which can generate a more stable negative pressure, thereby uniformly sucking the droplets into the droplet storage chamber 6, which is beneficial to product consistency and process realization.

[0083] The difference between this embodiment and embodiment 1 is that the droplet generation method using the above-mentioned digital PCR droplet generation device also includes a step of heating the liquid in the chip body 1 to accelerate the movement of the droplets.

[0084] Specifically, see Figure 8 As shown, after the absorbing liquid 9 is placed in the drainage chamber 7 to absorb the oil phase, the liquid level in the drainage chamber 7 is lowered, so that there is a liquid level difference between the droplet generation chamber 4 and the drainage chamber 7. According to the principle of communicating vessels, the liquid in the droplet generation chamber 4 will move into the droplet storage chamber 6, and the liquid in the droplet storage chamber 6 will move into the drainage chamber 7, until the liquid levels of the droplet generation chamber 4 and the drainage chamber 7 are consistent. In this process, the droplets gradually enter the droplet storage chamber 6 and gradually achieve flattening. However, due to the viscosity of the liquid and the capillary force in the chip, the droplets will move into the droplet storage chamber 6 at an extremely slow speed, and the droplet flattening process cannot be completed or takes a long time to complete, which does not meet the actual usage scenario.

[0085] In this embodiment, the temperature of the oil phase liquid in the chip body 1 is increased by heating the bottom of the chip body 1, so that the viscosity of the oil phase liquid is reduced, so that the droplets can move faster from the droplet generation chamber 4 to the droplet storage chamber 6, and gradually spread in the droplet storage chamber 6. During heating, the temperature of the oil phase liquid in the chip body 1 is controlled at 30°C to 90°C, preferably around 60°C. Among them, the viscosity of the oil phase liquid in the chip body 1 decreases with the increase of temperature, and is transmitted to the liquid inlet 5 and the liquid discharge port 8, so that the temperature of the chip body 1 as a whole increases. At this time, the oil phase liquid drives the droplets to flow to the droplet storage chamber 6 until the liquid surface of the droplet generation chamber 4 and the liquid discharge chamber 7 remain flush. When the flow rate is too fast, the viscosity of the oil phase liquid is changed by controlling the heating temperature at the bottom of the chip body 1, thereby achieving the purpose of controlling the flow rate.

[0086] When the liquid level difference between the drainage chamber 7 and the droplet generation chamber 4 is large, the liquid flow rate in the chip body 1 is relatively fast, and when the liquid level difference is small, the liquid flow rate in the chip body 1 is relatively slow. Therefore, the heating temperature of the chip body 1 increases as the liquid level difference between the drainage chamber 7 and the droplet generation chamber 4 decreases, that is, when the liquid level difference is large, the heating temperature decreases; when the liquid level difference decreases, the heating temperature increases.

[0087] In specific implementation, the chip body 1 can be placed on an in-situ PCR thermal cycle platform for temperature control, so that the platform and the bottom of the chip body 1 maintain a planar contact to conduct heat. In this way, the droplets are quickly transferred by heating and quickly spread in the droplet storage chamber 6, which makes it easier to realize productization. When in use, it is only necessary to suck out the oil phase liquid in the negative pressure hole at a very fast speed through the liquid suction 9 to lower the liquid level of the drainage chamber 7, and generate a liquid level height difference between the droplet generation chamber 4 and the drainage chamber 7. Then, through temperature control, the expected function can be achieved, and it only takes a short time to suck the oil phase in the drainage port 8, which can also meet the purpose of saving time.

[0088] Example 3

[0089] See also Figures 9 and 10 As shown, another structural form of the chip body 1 is shown, which has a single droplet storage chamber 6, and accordingly, only has a set of liquid inlet pipes 2 and liquid discharge pipes 3. The droplet storage chamber 6 is set in a polygonal shape, and the liquid inlet 5 and the liquid outlet 8 are directly connected to the droplet storage chamber 6 at the opposite corners of the polygon of the droplet storage chamber 6. After the droplets are generated in the droplet generation chamber 4, the liquid absorbing liquid 9 is inserted into the liquid discharge chamber 7 to absorb the oil phase in the droplet storage chamber 6, so that the droplets are transferred from the droplet generation chamber 4 to the droplet storage chamber 6 through the liquid inlet 5.

[0090] Example 4

[0091] See also Fig.11 , Fig.12 , which shows another structural form of a chip body 1, specifically a chip substrate 1a of the chip body 1. In this embodiment, the chip substrate 1a is located below the chip cover plate 1b, a groove with an opening facing upward is provided on the chip body 1a, the chip cover plate 1b is a flat plate, and the chip cover plate 1b is covered on the chip body 1a to form the chip body 1.

[0092] In this embodiment, eight droplet generation chambers 6 are provided on the chip body 1 and have a higher flux. Specifically, all the droplet generation chambers 6 are arranged along the length extension direction of the chip body 1. The cross-section of each droplet generation chamber 6 is roughly rectangular, and the two ends in the length direction respectively form a first inner angle and a second inner angle, and the other inner angles on the cross-section of the droplet storage chamber 6 are all set with arc chamfers. A first connecting port 63 is provided on the first inner angle, and the first connecting port 63 is connected to the liquid inlet 5 through a straight first channel 61; a second connecting port 64 is provided on the second inner angle, and the second connecting port 64 is connected to the liquid outlet 8 through a straight second channel 62, and the first channel 61 and the second channel 62 extend along the same length direction.

[0093] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it. They cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A digital PCR droplet generation device, comprising a chip body, wherein the chip body has a droplet generation chamber and a droplet storage chamber connected to the droplet generation chamber, characterized in that: It also includes an absorbing liquid having a absorbing function, the absorbing liquid is used in conjunction with the chip body to drive the droplets to move from the droplet generation chamber to the droplet storage chamber, wherein the chip body also has a drainage chamber connected to the droplet storage chamber, the absorbing liquid can be inserted into the drainage chamber, the bottom of the drainage chamber has a drainage port connected to the droplet storage chamber, the diameter of the bottom end of the absorbing liquid is larger than the aperture of the drainage port, The liquid absorbent includes a main body that can be inserted into the drainage cavity, and a head located above the main body, the head is exposed outside the drainage cavity, and the lower part of the main body also has a root extending downward, and the cross-sectional size of the root is smaller than the cross-sectional size of the main body.

2. The digital PCR droplet generation device according to claim 1, characterized in that: The liquid absorbing agent can be detachably arranged on the chip body, or the liquid absorbing agent can be inserted into the liquid discharge cavity separately from the chip body.

3. The digital PCR droplet generation device according to claim 1, characterized in that: The chip body is provided with a liquid discharge tube extending vertically upward, and the tube cavity of the liquid discharge tube forms the liquid discharge cavity.

4. The digital PCR droplet generation device according to claim 1, characterized in that: When the liquid absorbing element cooperates with the chip body, the liquid absorbing element is upright inserted into the liquid discharge cavity along a vertical direction.

5. The digital PCR droplet generation device according to claim 1, characterized in that: The cross-sectional area of ​​the root is 0.25 to 1 mm 2 .

6. The digital PCR droplet generation device according to claim 1, characterized in that: The length of the root is 1 to 8 mm.

7. The digital PCR droplet generation device according to claim 1, characterized in that: The main body is in the shape of a frustum that is larger at the top and smaller at the bottom.

8. The digital PCR droplet generation device according to claim 1, characterized in that: The head is in a truncated cone shape, and the diameter of the head is larger than the caliber of the drainage cavity.

9. The digital PCR droplet generation device according to claim 1, characterized in that: A clamping piece for easy clamping is fixedly arranged on the head.

10. The digital PCR droplet generation device according to claim 9, characterized in that: The clamping piece is a cap body fixedly buckled on the head.

11. The digital PCR droplet generation device according to claim 1, characterized in that: The liquid-absorbing material is made of a material having a capillary effect.

12. The digital PCR droplet generation device according to claim 1, characterized in that: The liquid-absorbing material has a porous structure or a fibrous structure material.

13. The digital PCR droplet generation device according to claim 1, characterized in that: The material for absorbing liquid is selected from capillary glass, activated carbon, wood, cloth, and paper material.

14. The digital PCR droplet generation device according to claim 1, characterized in that: The absorbent liquid is an absorbent liquid capable of absorbing a volume of liquid in the droplet storage chamber.

15. The digital PCR droplet generation device according to claim 1, characterized in that: The chip body is provided with a liquid inlet tube extending vertically upward, the lumen of the liquid inlet tube forms the droplet generation chamber, and the bottom of the droplet generation chamber is provided with a liquid inlet port communicating with the droplet storage chamber.

16. The digital PCR droplet generation device according to claim 15, characterized in that: The bottom wall of the droplet generation chamber is arranged to extend obliquely toward the liquid inlet.

17. The digital PCR droplet generation device according to claim 1, characterized in that: The chip body is provided with a liquid inlet and a liquid discharge port, the liquid droplets in the liquid droplet generation chamber enter the liquid droplet storage chamber through the liquid inlet, and the oil phase in the liquid droplet generation chamber is absorbed by the liquid absorption chamber through the liquid discharge port.

18. The digital PCR droplet generation device according to claim 17, characterized in that: The chip body also includes a first channel connecting the liquid inlet with the droplet storage chamber and a second channel connecting the liquid discharge port with the droplet storage chamber, wherein the first channel is connected to the droplet storage chamber at an end, and the second channel is connected to the droplet storage chamber at an end, wherein the first channel, the second channel and the bottom surface of the droplet storage chamber are located at the same height.

19. The digital PCR droplet generation device according to claim 18, characterized in that: The droplet storage chamber has a first communication port connected to the first channel and a second communication port connected to the second channel. The droplet storage chamber is a polygon with a first inner angle and a second inner angle. The first communication port is arranged on the first inner angle, and the second communication port is arranged on the second inner angle. The angles of the first inner angle and the second inner angle are 10° to 120°.

20. The digital PCR droplet generation device according to claim 19, characterized in that: The first interior angle is diagonally opposite to the second interior angle.

21. The digital PCR droplet generation device according to claim 1, characterized in that: A plurality of support columns are also arranged at intervals in the liquid drop storage cavity, and the support columns are supported between the bottom surface and the top surface of the liquid drop storage cavity along the thickness direction of the chip body.

22. A method for generating droplets of digital PCR, comprising a droplet generation step and a droplet transfer step, characterized in that: In the droplet transfer step, the oil phase is sucked by a liquid aspirator having a liquid aspirating function to promote the movement of the droplets, wherein the droplet generation method is implemented based on the digital PCR droplet generation device according to any one of claims 1 to 21.

23. The digital PCR droplet generation method according to claim 22, characterized in that: The method also includes heating the liquid in the chip body to accelerate the movement of the liquid droplets.

24. The method for generating digital PCR droplets according to claim 23, characterized in that: The bottom of the chip body is heated to control the temperature of the liquid in the chip body to be maintained at 30-90°C.

25. The method for generating digital PCR droplets according to claim 23, characterized in that: The chip body has a liquid discharge cavity communicated with the liquid droplet storage cavity, and the heating temperature of the chip body increases as the liquid level height difference between the liquid discharge cavity and the liquid droplet generation cavity decreases.

26. The method for generating digital PCR droplets according to claim 22, characterized in that: The liquid droplets in the droplet generation chamber are transferred to the droplet storage chamber by using the liquid suction device.

27. The method for generating digital PCR droplets according to claim 26, characterized in that: After the droplet formation begins, or after the droplet generation is completed, the absorbing liquid absorbs the oil phase again.

28. The method for generating digital PCR droplets according to claim 27, characterized in that: The chip body has a liquid discharge cavity communicated with the liquid droplet storage cavity. After the liquid droplets are generated in the liquid droplet generation cavity, the liquid absorption liquid is inserted into the liquid discharge cavity to absorb the oil phase.

29. The method for generating digital PCR droplets according to claim 28, characterized in that: The liquid suction device is inserted into the liquid discharge cavity along a vertical direction by using a mechanical arm.

30. The method for generating digital PCR droplets according to claim 23, characterized in that: The droplet generation step comprises: (1) Filling the droplet generation chamber and the droplet storage chamber of the chip body with an oil phase; (2) Injecting an aqueous phase into the droplet generation chamber to form droplets in the droplet generation chamber.

31. The method for generating digital PCR droplets according to claim 30, characterized in that: In the step (2), a water phase is injected into the droplet storage chamber using a microchannel, and the microchannel is vibrated while injecting the water phase, so that droplets are formed in the droplet generation chamber.

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