Micro-fluidic channel and micro-fluidic chip

Abstract

The utility model discloses a micro-fluidic channel and a micro-fluidic chip. The micro-fluidic channel comprises a main flow channel, a first branch flow channel, a second branch flow channel, a capturing channel and a regulating valve. Wherein the first branch flow channel communicates with the main flow channel, and a capturing cavity is formed in the end, away from the main flow channel, of the first branch flow channel; the second branch flow channel communicates with the main flow channel and is sequentially provided with a recovery port and an outlet in the liquid flowing direction, and the recovery port is formed in the downstream of the communicating position of the second branch flow channel and the main flow channel; one end of the capturing channel is communicated with the capturing cavity, and the other end is communicated with the recovery port; the adjusting valve is arranged in the capturing channel and comprises a deformation piece, and the deformation piece can deform relative to the capturing channel so as to adjust the resistance of the capturing channel. By adjusting the adjusting valve, the capturing channel has different resistances, and capturing of various liquid drops with different sizes and recovery of the captured liquid drops can be achieved.

Description

Technical Field

[0001] This application relates to the field of microfluidic chip technology, and in particular to a microfluidic channel and a microfluidic chip. Background Technology

[0002] In biochemical experiments and applications, there is often a need for real-time observation and localized observation of droplets, or for localized culture of cells. This requires capturing small droplets or cells before these experimental operations can be performed. Droplet capture utilizes capture structures to capture individual droplet particles or cell particles in continuous or intermittent flow fluids. However, current droplet capture technologies typically only capture droplets of a specific size, making it difficult to meet the needs of capturing droplets of various sizes, and the captured droplets are also difficult to recover. Utility Model Content

[0003] To solve at least one of the above-mentioned technical problems, this application provides a microfluidic channel and a microfluidic chip, which can capture droplets of various sizes and recover the captured droplets. The technical solution adopted is as follows.

[0004] This application provides a microfluidic channel in a first aspect, including a main channel, a first branch channel, a second branch channel, a capture channel, and a regulating valve. The first branch channel is connected to the main channel, and a capture chamber is provided at the end of the first branch channel furthest from the main channel. The second branch channel is connected to the main channel, and a recovery port and an outlet are sequentially provided along the liquid flow direction. The recovery port is located downstream of the junction of the second branch channel and the main channel. One end of the capture channel is connected to the capture chamber, and the other end is connected to the recovery port. The regulating valve is disposed in the capture channel and includes a deformable element that is deformable relative to the capture channel to adjust the resistance of the capture channel.

[0005] In some embodiments of this application, the regulating valve further includes an air chamber, and the deformable element includes a deformable membrane that separates the air chamber and the capture channel. The deformable membrane is used to bulge into the capture channel to compress the space of the capture channel when the air chamber is inflated.

[0006] In some embodiments of this application, the deformable film is used to bulge in a direction away from the capture channel when the gas chamber is under negative pressure to release the captured droplets.

[0007] In some embodiments of this application, the top wall of the capture channel is configured as an arc surface.

[0008] In some embodiments of this application, the extension direction of the first branch channel is on the same straight line as the extension direction of the main channel.

[0009] In some embodiments of this application, the second branch channel is provided with a first bend section, the protrusion of the first bend section is oriented toward the capture channel, and the recovery port is provided on the first bend section.

[0010] In some embodiments of this application, the inlet direction of the second branch channel is set at an angle to the main channel.

[0011] In some embodiments of this application, the second branch channel is further provided with a second bend section, which is disposed between the inlet of the second branch channel and the first bend section, and the protrusion direction of the second bend section is opposite to that of the capture cavity.

[0012] In some embodiments of this application, the width of the capture cavity is greater than the width of the first branch channel or the capture channel.

[0013] This application provides a microfluidic chip in a second aspect, including the microfluidic channel provided in the first aspect of this application. The microfluidic chip includes a first structural layer and a second structural layer stacked along the thickness direction. A main channel, a first branch channel, a second branch channel and a capture channel are disposed in the first structural layer. The air chamber of the regulating valve is disposed in the second structural layer. The first structural layer and the second structural layer are encapsulated and connected.

[0014] The embodiments of this application have at least the following beneficial effects: By setting one end of the capture channel to be connected to the capture chamber, the capture channel can be connected to the first branch channel through the capture chamber. A regulating valve set in the capture channel can adjust the resistance of the first branch channel by adjusting the resistance of the capture channel, thereby controlling the size of the droplets entering the capture chamber to obtain droplets of different sizes. Specifically, the regulating valve includes a deformable component. By controlling the regulating valve to deform the deformable component relative to the capture channel, the space of the capture channel can be changed by the deformable component, thereby changing the size of the capture channel to adjust its resistance. The captured droplets can be observed or further reacted in the capture chamber. It is evident that by adjusting the regulating valve, the capture channel can have different resistances, enabling the capture of droplets of various sizes to meet experimental requirements. The other end of the capture channel is connected to the recovery port. Thus, by reducing the resistance of the capture channel, the captured droplets can flow through the recovery port to the outlet of the second branch channel, thereby releasing the droplets and achieving the recovery of the captured droplets. Attached Figure Description

[0015] The present application will be further illustrated below with reference to the accompanying drawings and embodiments. It should be noted that the embodiments illustrated in the following drawings are exemplary and are only used to explain the present application, and should not be construed as limiting the present application.

[0016] Figure 1 This is a schematic diagram of the structure of the microfluidic channel provided in the embodiments of this application;

[0017] Figure 2 for Figure 1 AA cross-section view;

[0018] Figure 3 This is a schematic diagram of the structure of the microfluidic chip provided in the embodiments of this application.

[0019] Reference numerals: 100, microfluidic channel; 10, main channel; 20, first branch channel; 30, second branch channel; 31, recovery port; 32, outlet; 33, first bend section; 34, second bend section; 40, capture channel; 50, regulating valve; 51, deformable film; 52, air chamber; 60, capture cavity; 200, microfluidic chip; 210, first structural layer; 220, second structural layer. Detailed Implementation

[0020] The embodiments of this application are described in detail below with reference to 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 this application, and should not be construed as limiting this application.

[0021] In the description of this application, it should be understood that the terms "center", "middle", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of this application.

[0022] In the description of this application, "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.

[0023] In the description of this application, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0024] In the description of this application, the use of terms such as "as one implementation," "an embodiment," "some examples," "some embodiments," "illustrative embodiment," "example," "specific example," "some examples," etc., indicates that the specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0025] Please see Figure 1 This application provides a microfluidic channel 100 in a first aspect, including a main channel 10, a first branch channel 20, a second branch channel 30, a capture channel 40, and a regulating valve 50. The first branch channel 20 is connected to the main channel 10, and a capture chamber 60 is provided at the end of the first branch channel 20 furthest from the main channel 10. The second branch channel 30 is connected to the main channel 10, and a recovery port 31 and an outlet 32 ​​are sequentially provided along the liquid flow direction. The recovery port 31 is located downstream of the junction of the second branch channel 30 and the main channel 10. One end of the capture channel 40 is connected to the capture chamber 60, and the other end is connected to the recovery port 31. The regulating valve 50 is disposed in the capture channel 40, and the regulating valve 50 includes a deformable element that is deformable relative to the capture channel 40 to adjust the resistance of the capture channel 40. By connecting one end of the capture channel 40 to the capture chamber 60, the capture channel 40 can be connected to the first branch channel 20 via the capture chamber 60. The regulating valve 50 located in the capture channel 40 can adjust the resistance of the first branch channel 20 by regulating the resistance of the capture channel 40, thereby controlling the size of the droplets entering the capture chamber 60 to obtain droplets of different sizes. Specifically, the regulating valve 50 includes a deformable component. By controlling the regulating valve 50 to deform the deformable component relative to the capture channel 40, the space of the capture channel 40 can be changed, thereby changing the size of the capture channel 40 to adjust its resistance. The captured droplets can be observed or further reacted within the capture chamber 60. Therefore, by adjusting the regulating valve 50, the capture channel 40 can have different resistances, enabling the capture of droplets of various sizes to meet experimental requirements. The other end of the capture channel 40 is connected to the recovery port 31. In this way, by reducing the resistance of the capture channel 40, the captured droplets can flow through the recovery port 31 to the outlet 32 ​​of the second branch channel 30 to release the droplets and realize the recovery of the captured droplets.

[0026] Understandably, the initial flow resistance of the first branch channel 20 is less than that of the second branch channel 30. The first droplet among the multiple droplets flowing through the main channel 10 will enter the first branch channel 20 and be captured by the capture chamber 60. The captured droplet will block the capture channel 40, causing the flow resistance of the first branch channel 20, which is connected to the capture channel 40, to be greater than that of the second branch channel 30. Subsequent droplets will then choose to flow through the second branch channel 30 to the outlet 32, preventing the remaining droplets from flowing into the capture chamber 60. Specifically, the initial flow resistance of the first branch channel 20 can be made less than that of the second branch channel 30 by adjusting the diameter or length of the first branch channel 20 and the second branch channel 30. The specific method for controlling the flow resistance of the first branch channel 20 and the second branch channel 30 is not limited here.

[0027] Optionally, the regulating valve 50 can be set on the top or bottom surface of the capture channel 40, or the regulating valve 50 can be set on both the top and bottom surfaces of the capture channel 40.

[0028] For example, the main channel 10, the first branch channel 20, the second branch channel 30, and the capture channel 40 can be made of PDMS (polydimethylsiloxane), silicone, COC (copolymers of cycloolefins), COP (Cyclo-Olefin polymer), PS (polystyrene), or PC (polycarbonate), etc.

[0029] For example, by adjusting the regulating valve 50, it is possible to capture droplets with diameters ranging from tens to hundreds of micrometers.

[0030] Please see Figure 2In some embodiments, the regulating valve 50 further includes an air chamber 52, and a deformable element including a deformable membrane 51. The deformable membrane 51 separates the air chamber 52 and the capture channel 40. The deformable membrane 51 is used to bulge into the capture channel 40 when the air chamber 52 is inflated, thereby compressing the space of the capture channel 40. By configuring the valve structure with an air chamber 52 and a deformable membrane 51, the pressure change of the air chamber 52 can be used to drive the deformable membrane 51. By inflating and pressurizing the air chamber 52, the deformable membrane 51 bulges into the capture channel 40, allowing it to occupy a portion of the space in the capture channel 40, thereby compressing the space of the capture channel 40 and increasing its resistance. Adjusting the amount of air in the air chamber 52 can adjust the size of the space occupied by the deformable membrane 51, thereby adjusting the resistance of the capture channel 40 to capture droplets of different sizes. In other embodiments, by continuously inflating the air chamber 52, the air pressure inside the air chamber 52 can be continuously varied. Within the deformation range of the deformable film 51, the degree of bulging of the deformable film 51 can be steplessly adjusted, thereby achieving stepless adjustment of the resistance of the capture channel 40.

[0031] For example, the material of the deformable film 51 can be PDMS or silicone.

[0032] As an alternative implementation, the deformable part of the regulating valve 50 can be configured as part of the inner wall surface of the capture channel 40. The inner wall surface of the capture channel 40 is made of a material with negative thermal expansion; heating a portion of the flow path in the capture channel 40 causes the flow path to contract, while cooling a portion causes it to expand. By adjusting the temperature of a portion of the flow path in the capture channel 40, the space of the capture channel 40 can be adjusted, thereby changing the size of the capture channel 40 to regulate its resistance and achieve the capture of droplets of different sizes.

[0033] In some embodiments, the deformable film 51 is used to bulge in the direction away from the capture channel 40 when the gas chamber 52 is under negative pressure to release the captured droplets. When the gas chamber 52 is under negative pressure, the deformable film 51 can bulge in the direction away from the capture channel 40, thus forming an additional space between the deformable film 51 and the capture channel 40, increasing the space of the capture channel 40. At this time, the resistance of the capture channel 40 is reduced, and the droplets in the capture chamber 60 can be released out of the capture channel 40, thereby flowing to the outlet 32 ​​for recovery.

[0034] Optionally, the regulating valve 50 may also be equipped with a pneumatic structure (e.g., an air pump). The pneumatic structure is connected to the air chamber 52 and is used to regulate the air pressure within the air chamber 52. For example, it may inflate the air chamber 52 to cause the deformable film 51 to bulge towards the capture channel 40, or draw air into the air chamber 52 to cause the deformable film 51 to bulge away from the capture channel 40. Of course, in other examples, the air chamber 52 may be connected to other microfluidic structures, utilizing the microfluidic structures to regulate the air pressure within the air chamber 52; this is not limited here.

[0035] In some embodiments, the top wall of the capture channel 40 is configured as an arc surface. By configuring the top wall of the capture channel 40 as an arc surface, when controlled by the regulating valve 50, the shape of the bulging deformable film 51 can be made to fit against the top wall of the capture channel 40. At this time, the resistance of the capture channel 40 can reach its maximum value, and the regulating valve 50 can be completely closed, achieving the capture of extremely small droplets and preventing droplets from flowing out of the capture chamber 60. Of course, the top wall of the capture channel 40 can also be configured as a flat surface, that is, the cross-section of the capture channel 40 is rectangular. The resistance of the capture channel can be adjusted according to the size requirements of the droplets to be captured.

[0036] Please refer to the previous document. Figure 1 In some embodiments, the extension direction of the first branch channel 20 is on the same straight line as the extension direction of the main channel 10. By aligning the first branch channel 20 and the main channel 10 on the same straight line, the resistance when droplets flow from the main channel 10 into the first branch channel 20 can be reduced, making it easier for droplets to enter the first branch channel 20 and improving the stability of droplet capture.

[0037] In some embodiments, the second branch channel 30 is provided with a first bend section 33, the protrusion of which faces the capture channel 40, and a recovery port 31 is provided on the first bend section 33. By providing a first bend section 33 to the second branch channel 30 and setting the protrusion of the first bend section 33 towards the capture channel 40, and connecting the capture channel 40 to the second branch channel 30 through the recovery port 31, the extension direction of the capture channel 40 can be aligned with that of the first branch channel 20. This not only makes the structure of the microfluidic channel 100 more compact, but also improves the control effect of the regulating valve 50 on the resistance of the first branch channel 20, thereby improving the controllability of the process of adjusting the size of the captured droplets.

[0038] For example, the bending angle of the first bending segment 33 is 90°.

[0039] In some embodiments, the inlet direction of the second branch channel 30 is set at an angle to the main channel 10. It is understood that when the inlet direction of the second branch channel 30 is set at an angle to the main channel 10, the flow resistance increases due to the increased contact area with the channel when the droplet flows through the junction of the second branch channel 30 and the main channel 10. However, since the first branch channel 20 and the main channel 10 are on the same straight line, the flow resistance remains unchanged when the droplet flows through the junction of the first branch channel 20 and the main channel 10. Therefore, when a droplet flows from the main channel 10 to the junction of the first branch channel 20 and the second branch channel 30, it will choose to directly enter the first branch channel 20, thereby achieving droplet capture.

[0040] In some embodiments, the second branch channel 30 is further provided with a second bend section 34, which is disposed between the inlet of the second branch channel 30 and the first bend section 33. The protrusion direction of the second bend section 34 is opposite to that of the capture cavity 60. Providing the second bend section 34 to the second branch channel 30 optimizes its structure. By dividing the second branch channel 30 into several flow segments through the first bend section 33 and the second bend section 34, the difficulty of setting up the second branch channel 30 is reduced, facilitating its connection with the main channel 10 and the capture channel 40. Furthermore, it simplifies the flow path of droplets within the second branch channel 30, ensuring normal droplet flow.

[0041] For example, the bending angle of the second bending segment 34 is 90°.

[0042] In some embodiments, the width of the capture chamber 60 is greater than the width of the first branch channel 20 or the capture channel 40. Setting the width of the capture chamber 60 to be greater than the width of the first branch channel 20 or the capture channel 40 provides sufficient space for observation of the captured droplets or for cultivating the captured droplets. Optionally, an indicator or solvent can also be added to the capture chamber 60 to directly experiment on the captured liquid.

[0043] Please see Figure 3This application provides a microfluidic chip 200 in a second aspect, including the microfluidic channel provided in the first aspect. The microfluidic chip 200 includes a first structural layer 210 and a second structural layer 220 stacked along the thickness direction. A main channel 10, a first branch channel 20, a second branch channel 30, and a capture channel 40 are disposed in the first structural layer 210, and the air chamber 52 of the regulating valve 50 is disposed in the second structural layer 220. The first structural layer 210 and the second structural layer 220 are encapsulated and connected. By disposing the main channel 10, the first branch channel 20, the second branch channel 30, and the capture channel 40 in the first structural layer 210, and disposing the air chamber 52 of the regulating valve 50 in another structural layer, the mutual encapsulation and connection of the first structural layer 210 and the second structural layer 220 can be used to achieve rapid connection and assembly of the main channel 10, the first branch channel 20, the second branch channel 30, the capture channel 40, and the regulating valve 50, making the structure of the microfluidic chip 200 easier to realize and improving the manufacturing efficiency of the microfluidic chip 200.

[0044] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application. Furthermore, unless otherwise specified, the embodiments and features described in the embodiments of this application can be combined with each other.

Claims

1. A microfluidic channel, characterized in that: include Mainstream path; A first branch channel is connected to the main channel, and a capture chamber is provided at the end of the first branch channel that is away from the main channel. The second branch channel is connected to the main channel. The second branch channel is provided with a recovery port and an outlet in sequence along the liquid flow direction. The recovery port is located downstream of the connection between the second branch channel and the main channel. A capture channel, one end of which is connected to the capture chamber and the other end of which is connected to the recovery port; A regulating valve is disposed in the capture channel, the regulating valve including a deformable element that is deformable relative to the capture channel to adjust the resistance of the capture channel.

2. The microfluidic channel according to claim 1, characterized in that: The regulating valve further includes an air chamber, and the deformable element includes a deformable membrane that separates the air chamber from the capture channel. The deformable membrane is used to bulge into the capture channel to compress the space of the capture channel when the air chamber is inflated.

3. The microfluidic channel according to claim 2, characterized in that: The deformable film is used to bulge in a direction away from the capture channel when the gas chamber is under negative pressure in order to release the captured droplets.

4. The microfluidic channel according to claim 1, characterized in that: The top wall of the capture channel is set as an arc surface.

5. The microfluidic channel according to claim 1, characterized in that: The extension direction of the first branch channel is on the same straight line as the extension direction of the main channel.

6. The microfluidic channel according to claim 5, characterized in that: The second branch channel is provided with a first bend section, the protrusion of the first bend section is oriented toward the capture channel, and the recovery port is provided on the first bend section.

7. The microfluidic channel according to claim 6, characterized in that: The inlet direction of the second branch channel is set at an angle to the main channel.

8. The microfluidic channel according to claim 7, characterized in that: The second branch channel is further provided with a second bend section, which is located between the inlet of the second branch channel and the first bend section, and the protrusion direction of the second bend section is opposite to that of the capture cavity.

9. The microfluidic channel according to any one of claims 1 to 8, characterized in that: The width of the capture cavity is greater than the width of the first branch channel or the capture channel.

10. A microfluidic chip, characterized in that: The microfluidic chip includes a microfluidic channel as described in any one of claims 1 to 9, wherein the microfluidic chip includes a first structural layer and a second structural layer stacked along the thickness direction, the main channel, the first branch channel, the second branch channel and the capture channel are disposed in the first structural layer, the air chamber of the regulating valve is disposed in the second structural layer, and the first structural layer and the second structural layer are encapsulated and connected.

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