Micro-fluidic chip

Abstract

The utility model discloses a micro-fluidic chip. Belongs to the technical field of detection consumables. The first sub-runner and the second sub-runner are arranged on the two opposite sides of the liquid drop tiling cavity in the second direction correspondingly, and the multiple first sub-liquid drop forming channels are arranged to communicate between the first sub-runner and the corresponding liquid drop tiling cavity; and arranging a plurality of second sub-droplet forming channels which are respectively communicated between the second sub-runners and the corresponding droplet tiling cavities, so that the plurality of first sub-droplet forming channels are respectively arranged at intervals along the first direction, and the plurality of second sub-droplet forming channels are respectively arranged at intervals along the first direction, therefore, the sample phase enters the liquid drop tiling cavity from the two sides of the liquid drop tiling cavity in the first direction instead of the side, away from the liquid discharging hole, of the liquid drop tiling cavity, the movement stroke of the liquid drops in the liquid drop tiling cavity can be effectively shortened, the liquid drop generation efficiency is improved, and the liquid drop tiling efficiency is improved. And meanwhile, the stacking proportion among the liquid drops is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of detection consumables, and in particular to a microfluidic chip. Background Art

[0002] Droplet digital PCR systems mostly use a split technical route, that is, droplet generation, PCR reaction and droplet detection are completed on different instruments respectively. This technical route makes it difficult to achieve closed operation of the entire process and does not meet the requirements of clinical diagnostic analysis.

[0003] With the continuous advancement of microfluidic chip technology, an increasing number of instruments are using microfluidic chips that integrate the entire process of droplet generation, droplet tiling, PCR reaction cycling, and droplet detection. However, existing microfluidic chips suffer from low droplet generation efficiency and a high rate of droplet stacking. Therefore, existing microfluidic chips need improvement. Utility Model Content

[0004] The main purpose of this application is to provide a microfluidic chip to solve the problem of low droplet generation efficiency in the prior art.

[0005] The present application provides a microfluidic chip, comprising a chip body and a sealing layer, wherein the chip body and the sealing layer are sealed and jointly formed with an injection hole, a droplet formation cavity, a droplet tiling cavity, and a liquid drainage hole that are sequentially connected, wherein the injection hole and the liquid drainage hole are arranged opposite to each other along a first direction, and the droplet tiling cavity is located between the injection hole and the liquid drainage hole;

[0006] In which, the droplet formation chamber includes a main channel, a first sub-branch channel, a second sub-branch channel, a first sub-droplet formation channel and a second sub-droplet formation channel, the main channel is connected between the injection hole and the first branch channel and the second branch channel, and the first sub-branch channel and the second sub-branch channel are respectively arranged on opposite sides of the droplet tiling chamber along the second direction, a plurality of first sub-droplet formation channels are respectively connected between the first sub-branch channel and the corresponding droplet tiling chamber, a plurality of second sub-droplet formation channels are respectively connected between the second sub-branch channel and the corresponding droplet tiling chamber, and the second direction and the first direction are perpendicular to each other in the horizontal direction.

[0007] Furthermore, the chip body structure is formed with a guide portion extending to the droplet tiling chamber, and a guide portion is respectively provided between at least partially adjacent two first sub-droplet forming channels and / or between at least partially adjacent two second sub-droplet forming channels, and the guide portion is used to guide the droplets to move toward the middle of the droplet tiling chamber.

[0008] Furthermore, the chip body includes a chip upper layer and a chip lower layer, the chip lower layer is located between the chip upper layer and the sealing layer, wherein the guide portion is fixedly connected to the sealing layer so that the sealing layer is sealed connected to the side of the chip lower layer away from the chip upper layer.

[0009] Furthermore, the chip upper layer is structured to form the injection hole and the drainage hole, and the chip upper layer, the chip lower layer and the sealing layer are jointly structured to form the droplet forming cavity and the droplet paving cavity.

[0010] Furthermore, the chip upper layer protrudes in a direction away from the chip lower layer to form a first receiving portion and a second receiving portion spaced apart from each other, wherein the first receiving portion forms the injection hole and the second receiving portion forms the drainage hole.

[0011] Furthermore, the droplet formation chamber also includes a third sub-channel, which connects the first sub-channel, the second sub-channel and the main channel along the second direction, wherein the main channel connects the middle part of the third sub-channel, and the first sub-channel and the second sub-channel are respectively connected at both ends of the third sub-channel.

[0012] Furthermore, one end of each of the first sub-droplet forming channels communicating with the droplet paving chamber is in a bell-mouth shape, and one end of each of the second sub-droplet forming channels communicating with the droplet paving chamber is in a bell-mouth shape.

[0013] Furthermore, the sealing layer is glass or a film.

[0014] Furthermore, the chip body is sealed and connected to the sealing layer and together form a bubble convergence cavity, which is connected between a side of the droplet paving cavity away from the injection hole and the drainage hole along the first direction.

[0015] Furthermore, the chip body and the sealing layer are jointly constructed to form a PCR reaction unit, wherein the PCR reaction unit includes the injection hole, the droplet formation cavity, the droplet paving cavity, the bubble gathering cavity and the drainage hole, which are connected in sequence;

[0016] Alternatively, the chip body and the sealing layer are jointly constructed to form a plurality of independent PCR reaction units, wherein each of the PCR reaction units includes the injection hole, the droplet formation cavity, the droplet paving cavity, the bubble convergence cavity and the drainage hole that are connected in sequence.

[0017] The present application arranges the first sub-channel and the second sub-channel on opposite sides of the droplet tiling chamber along the second direction, and arranges a plurality of the first sub-channels for forming droplets to be connected between the first sub-channel and the corresponding droplet tiling chamber, and arranges a plurality of the second sub-channels for forming droplets to be connected between the second sub-channel and the corresponding droplet tiling chamber, so that the plurality of the first sub-channels for forming droplets are arranged at intervals along the first direction, and the plurality of the second sub-channels for forming droplets are arranged at intervals along the first direction, so that the sample phase enters the droplet tiling chamber from both sides of the droplet tiling chamber along the first direction when passing through the droplet formation chamber, rather than entering from the side of the droplet tiling chamber away from the drainage hole. Therefore, the movement stroke of the droplets in the droplet tiling chamber can be effectively shortened, the droplet generation efficiency can be improved, and the proportion of stacking between droplets can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0019] Figure 1 This is an overall schematic diagram of a microfluidic chip in an embodiment disclosed in the present application, showing a first direction and a second direction.

[0020] Figure 2 for Figure 1 Cross-sectional view along direction A-A1.

[0021] Figure 3 This is a schematic diagram of a chip body in an embodiment disclosed in this application.

[0022] Figure 4 for Figure 3 Cross-sectional view along direction B-B1.

[0023] Figure 5 for Figure 3 Cross-sectional view along the C-C1 direction.

[0024] Figure 6 for Figure 3 Cross-sectional view along the D-D1 direction.

[0025] Figure 7 This is a schematic diagram of a chip body in another embodiment disclosed in this application.

[0026] Figure 8 for Figure 7 Cross-sectional view along direction E-E1.

[0027] The above drawings include the following reference numerals:

[0028] Microfluidic chip 100, chip body 10, chip upper layer 11, guide surface 111, first receiving portion 112, second receiving portion 113, first light-transmitting surface 114, LOGO position 115, identification position 116, PCR reaction unit identification position 117, chip lower layer 12, guide portion 121, support portion 13, sealing layer 20, second light-transmitting surface 21, injection hole 30, droplet formation cavity 40, main channel 41, branch channel 42, first sub-branch channel 421 , second sub-branch channel 422, third sub-branch channel 423, droplet formation channel 43, first sub-droplet formation channel 431, second sub-droplet formation channel 432, trumpet-shaped 433, droplet paving chamber 50, bubble convergence chamber 60, guide chamber 61, first sub-wall 611, second sub-wall 612, third sub-wall 613, guide hole 62, first step surface 63, first hole 621, second hole 622, third hole 623, drainage hole 70, second step surface 71. DETAILED DESCRIPTION

[0029] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0030] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0031] Unless otherwise specifically stated, the relative arrangement of the parts and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to actual proportional relationships. The techniques, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed here, any specific values ​​should be interpreted as being merely exemplary, not as limitations. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0032] See also Figure 1-5As shown, the present application provides a microfluidic chip 100, which includes a chip body 10 and a sealing layer 20. The chip body 10 and the sealing layer 20 are sealed together to form a liquid injection hole 30, a droplet formation cavity 40, a droplet paving cavity 50, a bubble convergence cavity 60 and a liquid discharge hole 70 that are sequentially connected.

[0033] The injection hole 30 is used to sequentially inject the oil phase and the sample phase into the chip body 10. After entering the chip body 10 through the injection hole 30, the oil phase flows through the droplet formation chamber and the droplet spreading chamber 50, completely filling the droplet formation chamber 40 and the droplet spreading chamber 50, and at least partially filling the injection hole 30, the bubble collection chamber 60, and the drainage hole 70. The sample phase is an aqueous phase.

[0034] The droplet formation chamber 40 separates the injected sample phase into droplets of uniform size based on the principle of step emulsification. The droplet spreading chamber 50 is used to accommodate the droplets. After the sample phase enters the chip body 10 through the injection hole 30, it comes into contact with and is enveloped by the oil phase. As it passes through the droplet formation chamber 40, it is dispersed into droplets of uniform size.

[0035] Please refer to Figure 2 As shown, during the addition of the oil phase or the sample phase, bubbles carried in the oil phase or the sample phase will flow into the droplet spreading chamber 50 along with the oil phase or the sample phase. The inner wall of the droplet spreading chamber 50 has a guide surface 111, which is used to guide the bubbles in the droplet spreading chamber 50 to move toward the bubble convergence chamber 60, thereby preventing the bubbles from being retained in the droplet spreading chamber 50.

[0036] The bubble convergence chamber 60 is connected between the droplet tiling chamber 50 and the drainage hole 70. When the microfluidic chip 100 is placed horizontally, the bubble convergence chamber 60 is at least partially located above the droplet tiling chamber 50, so that the bubbles entering the bubble convergence chamber 60 from the droplet tiling chamber 50 can directly enter the drainage hole 70 from the bubble convergence chamber 60, thereby being discharged from the microfluidic chip 100, avoiding bubbles remaining in the droplet tiling chamber 50 and changing in volume during the high and low temperature treatment process to disturb the droplets, causing adjacent droplets to merge with each other and affecting the detection results.

[0037] Furthermore, the chip body 10 includes a chip upper layer 11 and a chip lower layer 12. The chip upper layer 11 is configured to form the injection hole 30 and the drainage hole 70. The chip lower layer 12 is connected between the chip upper layer 11 and the sealing layer 20. Furthermore, the chip upper layer 11, the chip lower layer 12, and the sealing layer 20 collectively form the droplet formation cavity 40, the droplet paving cavity 50, and the bubble convergence cavity 60.

[0038] For further information, please refer to Figure 2 As shown, when the microfluidic chip 100 is placed horizontally, the sealing layer 20 is located at the bottom, the chip upper layer 11 is located at the top, and the chip lower layer 12 is located between the sealing layer 20 and the chip upper layer 11.

[0039] Furthermore, the top wall of the droplet paving chamber 50 is the guide surface 111. The guide surface 111 is an inclined surface and is inclined along the injection hole 30 toward the discharge hole 70 to guide the bubbles in the droplet paving chamber 50 to move toward the bubble convergence chamber 60.

[0040] Furthermore, the chip upper layer 11 protrudes in a direction away from the chip lower layer 12 to form a first receiving portion 112 and a second receiving portion 113 that are spaced apart from each other, wherein the first receiving portion 112 is configured to form the injection hole 30 and the second receiving portion 113 is configured to form the drainage hole 70.

[0041] The injection hole 30 is located above the droplet formation chamber 40 and the droplet tiling chamber 50 to ensure that the injected liquid completely fills the droplet formation chamber 40 and the droplet tiling chamber 50, and the drainage hole 70 is located above the droplet formation chamber 40, the droplet tiling chamber 50 and the bubble gathering chamber 60 to ensure that the bubbles in the bubble gathering chamber 60 can be directly discharged through the drainage hole 70.

[0042] Furthermore, in one embodiment, the chip upper layer 11 and the chip lower layer 12 are integrally formed, and the sealing layer 20 is a transparent film made of glass or a polymer material. The sealing layer 20 and the side of the chip lower layer 12 away from the chip upper layer 11 can be sealed by, but not limited to, adhesive bonding, welding, thermal compression bonding, and chemical bonding.

[0043] For further information, please refer to Figure 2As shown, the bubble convergence chamber 60 includes a guide chamber 61 and a guide hole 62, which are interconnected. The end of the guide chamber 61 away from the guide hole 62 is connected to the droplet spreading chamber 50, and the top wall of the guide chamber 61 is inclined along the droplet spreading chamber 50 toward the guide hole 62, so that bubbles guided from the droplet spreading chamber 50 to the guide chamber 61 can continue to be guided to the guide hole 62 through the guide chamber 61. The end of the guide hole 62 away from the guide chamber 61 is connected to the drainage hole 70.

[0044] Further, see Figure 4-6 As shown, the top wall of the guide cavity 61 includes a first sub-wall 611, a second sub-wall 612, and a third sub-wall 613. The first sub-wall 611 and the third sub-wall 613 are located on opposite sides of the second sub-wall 612 along the first direction from the droplet tiling cavity 50 toward the guide hole 62, that is, the first sub-wall 611, the second sub-wall 612, and the third sub-wall 613 are sequentially connected along the second direction, wherein the second direction is perpendicular to the first direction.

[0045] Furthermore, the first sub-wall 611, the second sub-wall 612, and the third sub-wall 613 are respectively inclined along the direction of the droplet spreading chamber 50 toward the guide hole 62. Therefore, bubbles moving from the droplet spreading chamber 50 to the first sub-wall 611, the second sub-wall 612, and the third sub-wall 613, respectively, will move along the corresponding first sub-wall 611, the second sub-wall 612, or the third sub-wall 613 toward the guide hole 62, thereby preventing bubbles from being retained in the guide chamber 61 and further preventing bubbles from returning from the guide chamber 61 to the droplet spreading chamber 50 during high and low temperature conditions.

[0046] Furthermore, in one embodiment, the first sub-wall 611 and the third sub-wall 613 are symmetrically arranged on opposite sides of the second sub-wall 612 along the direction from the droplet tiling chamber 50 toward the guide hole 62. This allows bubbles within the droplet tiling chamber 50 to stably move toward the guide cavity 61 corresponding to the first sub-wall 611 or the third sub-wall 613, thereby reducing or preventing the bubbles from moving in a disordered direction within the droplet tiling chamber 50.

[0047] Furthermore, the first sub-wall 611, the second sub-wall 612, and the third sub-wall 613 are each connected to the wall of the corresponding guide hole 62 on a side away from the droplet paving chamber 50. This effectively increases the communication space between the guide chamber 61 and the guide hole 62, facilitating smoother movement of bubbles within the guide chamber 61 into the guide hole 62.

[0048] Furthermore, in one embodiment, the guide surface 111 is the top wall of the droplet paving chamber 50, and there is a first step surface 63 between the top wall of the guide chamber 61 and the guide surface 111, and the first step surface 63 is used to prevent the bubbles in the guide chamber 61 from moving toward the droplet paving chamber 50.

[0049] Furthermore, a first step surface 63 is defined between the first sub-wall 611 , the second sub-wall 612 , and the third sub-wall 613 and the corresponding guide surface 111 .

[0050] Furthermore, the second sub-wall 612 is recessed along the guide hole 62 toward the drainage hole 70 and connected between the first sub-wall 611 and the third sub-wall 613. The first sub-wall 611 and the third sub-wall 613 are each inclined toward the second sub-wall 612. As a result, at least some of the bubbles entering the guide cavity 61 corresponding to the first sub-wall 611 and the third sub-wall 613 will first enter the guide cavity 61 corresponding to the second sub-wall 612. This allows more bubbles to gather in the guide cavity 61 corresponding to the second sub-wall 612, increasing the likelihood that these gathered bubbles will merge into larger bubbles. Consequently, the merged large bubbles have greater buoyancy to overcome forces such as surface tension, gravity, and viscosity, thereby moving more smoothly toward the guide hole 62.

[0051] In another embodiment, the guide surface 111 is the top wall of the droplet spreading chamber 50, and the top wall of the guide chamber 61 is connected to the guide surface 111. This allows bubbles in the droplet spreading chamber 50 to move smoothly toward the guide chamber 61 and then move toward the guide hole 62 under the action of the inclined top wall of the guide chamber 61.

[0052] Furthermore, the guide surface 111 has an inclination angle of 0.5° to 3° relative to the horizontal plane. This facilitates guiding the bubbles in the droplet paving chamber 50 toward the guide chamber 61 while effectively controlling the volume of the droplet paving chamber 50, thereby avoiding the need to inject a large amount of oil phase during detection. Furthermore, the overall volume of the microfluidic chip 100 can be effectively controlled, thereby avoiding waste of raw materials used to prepare the chip body 10.

[0053] The first sub-wall 611 has an inclination angle of 0.6° to 5° relative to the horizontal plane, the second sub-wall 612 has an inclination angle of 0.6° to 5° relative to the horizontal plane, and the third sub-wall 613 has an inclination angle of 0.6° to 5° relative to the horizontal plane. This facilitates guiding the bubbles in the guide cavity 61 toward the guide hole 62 while effectively controlling the volume of the guide cavity 61, avoiding the need to inject a large amount of oil phase during testing. Furthermore, the overall volume of the microfluidic chip 100 can be effectively controlled, avoiding waste of raw materials used to prepare the chip body 10.

[0054] Furthermore, the diameter of at least a portion of the guide hole 62 gradually decreases as it approaches the drainage hole 70. This causes multiple bubbles entering the guide hole 62 to converge toward the center, potentially leading to bubble stacking, which in turn promotes the fusion of these converged bubbles into larger bubbles, thereby facilitating the movement of these larger bubbles toward the drainage hole 70.

[0055] For further information, please refer to Figure 2 and Figure 4 As shown, in one embodiment, the guide hole 62 includes a first hole 621 and a second hole 622, and the second hole 622 is connected between the first hole 621 and the drainage hole 70. The diameter of the first hole 621 gradually decreases toward the second hole 622, so that the first hole 621 is a variable diameter hole, thereby facilitating the guidance of bubbles in the first hole 621 to the second hole 622.

[0056] Furthermore, when the microfluidic chip 100 is placed horizontally, the second hole 622 is located above the first hole 621. Preferably, the second hole 622 is located directly above the first hole 621, so that bubbles in the first hole 621 can move smoothly to the second hole 622.

[0057] In one embodiment, the second hole 622 is a constant diameter hole, and the diameter of the second hole 622 is equal to the minimum diameter of the first hole 621 , so that the second hole 622 is connected to the minimum diameter of the first hole 621 .

[0058] In another embodiment, the second hole 622 is a constant diameter hole, and the diameter of the second hole 622 is smaller than the minimum diameter of the first hole 621, so that a third hole 623 is provided at the minimum diameter between the second hole 622 and the first hole 621. The provision of the third hole 623 facilitates mold preparation and facilitates demolding when the integrated chip body 10 is injection molded.

[0059] Preferably, the diameter of the third hole 623 gradually decreases along the direction from the first hole 621 to the second hole 622 .

[0060] Furthermore, the diameter of the second hole 622 is smaller than that of the drainage hole 70. Thus, a second step surface 71 is formed at the connection between the second hole 622 and the drainage hole 70. This prevents bubbles entering the drainage hole 70 from returning to the guide hole 62 due to the second step surface 71.

[0061] Furthermore, in one embodiment, the diameter of the second hole 622 gradually decreases toward the first hole 621 , so that the second hole 622 is a variable diameter hole, wherein the minimum diameter of the second hole 622 is less than or equal to the minimum diameter of the first hole 621 .

[0062] By setting the second hole 622 as a variable diameter hole, when the microfluidic chip 100 is placed horizontally for detection (for example, in the process of decreasing from high temperature to low temperature), the second hole 622 as a variable diameter hole will limit the bubbles located in the second hole 622 and / or in the drainage hole 70 from moving toward the first hole 621.

[0063] In addition, by setting the second hole 622 as a variable diameter hole, and the variable diameter direction of the second hole 622 is opposite to the variable diameter direction of the first hole 621, it is also possible to facilitate demolding when the integrated chip body 10 is injection molded.

[0064] For further information, please refer to Figure 1-2 As shown, in one embodiment, the chip body 10 has a first light-transmitting surface 114, which is opposite to the guide surface 111 and located on the side of the guide surface 111 away from the droplet-laying cavity 50. During detection, light is emitted from the first light-transmitting surface 114 through the chip upper layer 11 and into the droplet-laying cavity 50, and then emitted from the sealing layer 20 corresponding to the bottom wall of the droplet-laying cavity 50.

[0065] Furthermore, the first light-transmitting surface 114 and the guiding surface 111 are parallel to each other, so that the optical path of the light source when passing through the chip upper layer 11 is substantially consistent.

[0066] Furthermore, in one embodiment, the chip body 10 and the sealing layer 20 are jointly constructed to form a PCR reaction unit, wherein the PCR reaction unit includes the injection hole 30, the droplet formation cavity 40, the droplet paving cavity 50, the bubble collection cavity 60, and the drainage hole 70, which are sequentially connected.

[0067] In another embodiment, the chip body 10 and the sealing layer 20 are jointly constructed to form a plurality of mutually independent PCR reaction units. Each of the PCR reaction units includes the injection hole 30, the droplet formation cavity 40, the droplet flattening cavity 50, the bubble collection cavity 60, and the drainage hole 70, which are sequentially connected.

[0068] Further, see Figure 7-8 Combined with Figure 5 As shown, the droplet formation chamber 40 includes a main channel 41, a branch channel 42, and a droplet formation channel 43. The main channel 41 communicates between the injection hole 30 and the branch channel 42, and the plurality of droplet formation channels 43 communicate between the branch channel 42 and the droplet spreading chamber 50, and one end of each droplet formation channel 43 communicating with the droplet spreading chamber 50 is in a bell-mouth shape 433.

[0069] Compared with the prior art in which trumpet-shaped portions 433 are provided at both ends of each droplet forming channel 43, in this embodiment, only one end of each droplet forming channel 43 connected to the droplet paving cavity 50 is formed into a trumpet-shaped portion 433, which can simplify the structure of the molding mold.

[0070] Furthermore, the lower chip and / or the upper chip are constructed with a guide portion 121 extending to the droplet tiling chamber 50, and at least one guide portion 121 is arranged between two adjacent droplet forming channels 43, and the guide portion 121 is used to guide the droplets to move toward the middle of the droplet tiling chamber 50.

[0071] Furthermore, the guide portion 121 protrudes from the droplet formation channel 43 and extends into the corresponding droplet spreading chamber 50, so that the droplets formed through the droplet formation channel 43 can move along the second direction toward the middle of the droplet spreading chamber 50 under the guidance of the guide portion 121, thereby improving the efficiency of the droplets spreading the droplet spreading chamber 50.

[0072] Furthermore, the guiding portion 121 is fixedly connected to the sealing layer 20 , so that the sealing layer 20 is sealed and connected to a side of the chip lower layer 12 away from the chip upper layer 11 .

[0073] Specifically, since the guide portion 121 is close to the droplet-forming channel 43, and the droplet-forming channel 43 is jointly constructed by the sealing layer 20, the chip upper layer 11 and the chip lower layer 12, by connecting the sealing layer 20 with the guide portion 121, the structural stability of the droplet-forming channel 43 can be effectively guaranteed, thereby making the specifications of the generated droplets consistent.

[0074] For further information, please refer to Figure 7-8As shown, in the first embodiment, the sealing layer 20 is glass or a film, the branch channel 42 and the bubble convergence chamber 60 are located on opposite sides of the droplet tiling chamber 50 along the first direction, and the plurality of droplet forming channels 43 are respectively connected between the branch channel 42 and the droplet tiling chamber 50 along the first direction.

[0075] In the second implementation, please refer to Figure 3 and Figure 5 As shown, the sealing layer 20 is glass or a film, and the branch channel 42 includes a first sub-branch channel 421 and a second sub-branch channel 422. The first sub-branch channel 421 and the second sub-branch channel 422 are located on opposite sides of the droplet tiling chamber 50 along the second direction.

[0076] The droplet formation channel 43 includes a first sub-droplet formation channel 431 and a second sub-droplet formation channel 432. Multiple first sub-droplet formation channels 431 are respectively connected between the first sub-branch channel 421 and the corresponding droplet tiling chamber 50 along the second direction, and multiple second sub-droplet formation channels 432 are respectively connected between the second sub-branch channel 422 and the corresponding droplet tiling chamber 50 along the second direction.

[0077] Furthermore, the flow channel 42 further includes a third sub-flow channel 423, which connects the first sub-flow channel 421, the second sub-flow channel 422, and the main flow channel 41 along the second direction. The main flow channel 41 connects to the middle of the third sub-flow channel 423, and the first sub-flow channel 421 and the second sub-flow channel 422 are respectively connected to the two ends of the third sub-flow channel 423.

[0078] By providing the first sub-channels 421 and the second sub-channels 422, the plurality of first sub-droplet formation channels 431 are spaced apart along the first direction, and the plurality of second sub-droplet formation channels 432 are spaced apart along the first direction. This allows the sample phase to enter the droplet spreading chamber 50 from both sides of the droplet spreading chamber 50 along the first direction, rather than from the side of the droplet spreading chamber 50 away from the drainage hole 70. This effectively shortens the travel distance of droplets within the droplet spreading chamber 50, improves droplet generation efficiency, and reduces the incidence of droplet stacking.

[0079] Furthermore, the first sub-dividing channel 421 and the second sub-dividing channel 422 are provided, and the guiding portion 121 is provided between the two adjacent first sub-droplet forming channels 431 and between the two adjacent second sub-droplet forming channels 432, respectively. This can more efficiently guide the droplets to move toward the middle of the droplet tiling chamber 50. At the same time, it can also enable the sealing layer 20 to be connected to the partition portion along the first direction at a position close to the bubble convergence chamber 60, thereby effectively increasing the connection strength between the droplet tiling chamber 50 and the droplet forming chamber 40.

[0080] Furthermore, compared with the prior art in which the branch channel (the first sub-branch channel 421 and the second sub-branch channel 422) and the droplet formation channel (the first sub-droplet formation channel 431 and the second sub-droplet formation channel 432) are extended to the middle of the droplet tiling chamber 50, this embodiment arranges the first sub-branch channel 421 and the second sub-branch channel 422 on opposite sides of the droplet tiling chamber 50, which can avoid occupying the detection area of ​​the droplet tiling chamber 50, thereby helping the inspection personnel to more efficiently inspect the various inspection areas of the droplet tiling chamber 50.

[0081] Further, in one embodiment, please refer to Figure 2 As shown, the sealing layer 20 has a second light-transmitting surface 21, which corresponds to the droplet-laying cavity 50, and the guide surface 111 is inclined relative to the second light-transmitting surface 21. During detection, light passes through the sealing layer 20 from the second light-transmitting surface 21 and enters the droplet-laying cavity 50. It is then reflected from the top wall of the droplet-laying cavity 50 and emitted from the sealing layer 20. In this embodiment, the top wall of the droplet-laying cavity 50 is not transparent to the light emitted by the light source.

[0082] For further information, please refer to Figure 5 As shown, the chip body 10 is also constructed to have a plurality of support portions 13 extending into the droplet tiling cavity 50. The plurality of support portions 13 are arranged at intervals and are respectively fixedly connected to the sealing layer 20, so that the portion of the sealing layer 20 corresponding to the droplet tiling cavity 50 can be stably supported, thereby ensuring the flatness of the portion, so as to facilitate the droplet awakening fluorescence imaging detection.

[0083] For further information, please refer to Figure 1 As shown, the surface of the chip upper layer 11 is also provided with a logo position 115, an identification position 116, and a PCR reaction unit identification position 117. The logo position 115 is used for pasting or lasering a product logo, the identification position 116 can be used to identify the test item or type, etc., and the PCR reaction unit identification position 117 is used to distinguish between the individual PCR reaction units.

[0084] Furthermore, the working principle of the present invention is as follows:

[0085] First, the oil phase is injected into the injection hole 30 so that the injected oil phase fills the main channel 41, the branch channel 42, the droplet formation channel 43, the droplet paving chamber 50, the bubble convergence chamber 60 and at least part of the drainage hole 70.

[0086] Then, the sample phase is injected from the injection hole 30, so that the injected sample phase flows through the flow channel and the branch channel 42 and then enters the droplet formation channel 43, and forms droplets of uniform specifications based on the step emulsification principle in the droplet formation channel 43 and then enters the droplet tiling chamber 50, and multiple droplets are in a tiling or partially stacked state in the droplet tiling chamber 50.

[0087] Secondly, the microfluidic chip 100 is subjected to high and low temperature cyclic heating from one side of the sealing layer 20 to perform a PCR reaction cycle on the droplets in the droplet tiling area, and after the PCR reaction cycle is completed, the droplets in the droplet tiling chamber 50 are in a tiling state.

[0088] Finally, the spread droplets are subjected to fluorescence imaging detection.

[0089] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figures. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0090] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of this application.

[0091] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A microfluidic chip, characterized in that: The chip body comprises a chip body and a sealing layer, wherein the chip body and the sealing layer are sealed and jointly formed with an injection hole, a droplet formation cavity, a droplet flattening cavity and a liquid discharge hole which are sequentially connected, the injection hole and the liquid discharge hole being arranged opposite to each other along a first direction, and the droplet flattening cavity being located between the injection hole and the liquid discharge hole; In which, the droplet formation chamber includes a main channel, a first sub-branch channel, a second sub-branch channel, a first sub-droplet formation channel and a second sub-droplet formation channel, the main channel is connected between the injection hole and the first sub-branch channel and the second sub-branch channel, and the first sub-branch channel and the second sub-branch channel are respectively arranged on opposite sides of the droplet tiling chamber along the second direction, a plurality of first sub-droplet formation channels are respectively connected between the first sub-branch channel and the corresponding droplet tiling chamber, a plurality of second sub-droplet formation channels are respectively connected between the second sub-branch channel and the corresponding droplet tiling chamber, and the second direction and the first direction are perpendicular to each other in the horizontal direction.

2. The microfluidic chip according to claim 1, characterized in that The chip body structure is formed with a guide portion extending to the droplet tiling chamber, and a guide portion is respectively provided between at least partially adjacent two first sub-droplet formation paths and / or between at least partially adjacent two second sub-droplet formation paths, and the guide portion is used to guide the droplets to move toward the middle of the droplet tiling chamber.

3. The microfluidic chip according to claim 2, characterized in that: The chip body includes a chip upper layer and a chip lower layer, the chip lower layer is located between the chip upper layer and the sealing layer, wherein the guide portion is fixedly connected to the sealing layer so that the sealing layer is sealed and connected to a side of the chip lower layer away from the chip upper layer.

4. The microfluidic chip according to claim 3, characterized in that The chip upper layer is structured to form the injection hole and the drainage hole, and the chip upper layer, the chip lower layer and the sealing layer are structured together to form the droplet forming cavity and the droplet paving cavity.

5. The microfluidic chip according to claim 3, characterized in that: The chip upper layer protrudes in a direction away from the chip lower layer to form a first receiving portion and a second receiving portion spaced apart from each other, wherein the first receiving portion forms the injection hole, and the second receiving portion forms the drainage hole.

6. The microfluidic chip according to claim 1, characterized in that The droplet formation chamber also includes a third sub-channel, which connects the first sub-channel, the second sub-channel and the main channel along the second direction, wherein the main channel is connected to the middle part of the third sub-channel, and the first sub-channel and the second sub-channel are respectively connected to the two ends of the third sub-channel.

7. The microfluidic chip according to claim 1, characterized in that One end of each of the first sub-droplet forming channels communicating with the droplet tiling chamber is in a bell-mouth shape, and one end of each of the second sub-droplet forming channels communicating with the droplet tiling chamber is in a bell-mouth shape.

8. The microfluidic chip according to claim 1, characterized in that The sealing layer is glass or a film.

9. The microfluidic chip according to any one of claims 1 to 8, characterized in that: The chip body is sealed and connected to the sealing layer and together forms a bubble convergence cavity, which is connected between a side of the droplet paving cavity away from the injection hole and the drainage hole along the first direction.

10. The microfluidic chip according to claim 9, characterized in that: The chip body and the sealing layer are jointly constructed to form a PCR reaction unit, wherein the PCR reaction unit includes the injection hole, the droplet formation cavity, the droplet paving cavity, the bubble gathering cavity and the drainage hole which are connected in sequence; Alternatively, the chip body and the sealing layer are jointly constructed to form a plurality of independent PCR reaction units, wherein each of the PCR reaction units includes the injection hole, the droplet formation cavity, the droplet paving cavity, the bubble convergence cavity and the drainage hole that are connected in sequence.

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