Negative pressure driving device for micro-fluidic chip and micro-fluidic mixer

Abstract

The invention provides a negative pressure driving device for a micro-fluidic chip and a micro-fluidic mixer, and belongs to the technical field of micro-fluidic. In order to solve the problems that a micro-fluidic driving mechanism is inconvenient to use and poor in portability, the negative pressure driving device for the micro-fluidic chip comprises a shell and a valve mechanism arranged on the shell, a driving mechanism and a counting mechanism are arranged on the two sides of the valve mechanism respectively, and a micro-fluidic chip containing area is arranged on the surface of the shell. A vacuum cavity is formed in the shell, and the driving end of the driving mechanism is arranged in the vacuum cavity and can change the vacuum degree of the vacuum cavity. The micro-fluidic chip accommodating area is provided with an opening communicated with the vacuum cavity, the valve mechanism is arranged at the opening, and the valve mechanism is used for opening and closing communication between the opening and the vacuum cavity; the counting mechanism is in transmission connection with the driving mechanism and is used for counting the driving times of the driving mechanism. Through the integrated driving device and negative pressure driving, the structure is compact, and the size is reduced, so that the use convenience and portability of the microfluidic driving mechanism are improved.

Description

Technical Field

[0001] The present application relates to the field of microfluidics, and in particular to a negative pressure driving device and a microfluidic mixer for a microfluidic chip. Background Art

[0002] Microfluidics refers to the manipulation of liquids at the submillimeter scale, where the submillimeter scale is generally a few microns to hundreds of microns. Microfluidic technology has great advantages in the preparation of small-scale drugs. For example, nanoscale delivery carriers are one of the core technical barriers of many molecular drugs. Delivery carriers are responsible for protecting and allowing drug molecules to pass through various cell barriers of the body and be effectively absorbed by the body. At present, the main methods for preparing delivery nanoparticles include high-pressure homogenization, nanoprecipitation, material self-assembly, in situ synthesis / polymerization, etc. However, the nanoparticles produced by these methods have uneven structures, wide particle size distributions, complex synthesis steps, and large batch-to-batch differences, which greatly limits their application in the preparation of delivery materials. In contrast, the use of microfluidic mixing technology to prepare nanoparticles has the advantages of being relatively simple and rapid, with controllable conditions, strong repeatability, and easy to achieve production scale-up.

[0003] Currently, the main driving method for preparing nanoparticles using microfluidic mixers is positive pressure drive by an electronic pump. This involves applying positive pressure to the incoming phase, mixing two or more phases through the reaction zone, and finally collecting them. This method requires high precision and high cost for the drive equipment, requires stable power supply control, and is not portable.

[0004] In addition, a manual negative pressure drive method has also emerged, which usually uses a syringe to achieve manual negative pressure. It is mainly used in laboratories, but it needs to be used in conjunction with other equipment, such as catheters, connectors, etc., and has high requirements on the operator and operating environment. It is inconvenient to use and not easy to carry. Summary of the Invention

[0005] The purpose of this application is to address the problems of inconvenient use and poor portability of microfluidic drive mechanisms in the prior art. Therefore, this application provides a negative pressure drive device and a microfluidic mixer for a microfluidic chip. By using an integrated drive device and negative pressure drive, the device achieves a compact structure and reduced size, thereby improving the ease of use and portability of the microfluidic drive mechanism.

[0006] The embodiment of the present application provides a negative pressure driving device for a microfluidic chip, comprising a housing and a valve mechanism disposed on the housing, wherein a driving mechanism and a counting mechanism are respectively disposed on both sides of the valve mechanism.

[0007] The shell surface is provided with a microfluidic chip accommodating area, the shell interior is provided with a vacuum cavity, the driving end of the driving mechanism is provided in the vacuum cavity and can change the vacuum degree of the vacuum cavity;

[0008] The microfluidic chip accommodating area is provided with an opening communicating with the vacuum chamber, the valve mechanism is provided at the opening, and the valve mechanism is used to open and close the communication between the opening and the vacuum chamber;

[0009] The counting mechanism is in transmission connection with the driving mechanism, and the counting mechanism is used to count the number of driving times of the driving mechanism.

[0010] By adopting the above technical solution, a microfluidic chip accommodating area is set on the surface of the shell, and a driving mechanism and a valve mechanism are set on the shell, so that multiple operating components for driving the microfluidic chip are integrated, and the microfluidic chip can be driven directly by a single device, which is convenient to use; the number of drives, that is, the number of times the driving device is used, is counted by a counting mechanism that is transmission-connected to the driving mechanism, so that the operator can be prompted to use it within the specified number of times, ensuring that the driving device can provide reliable driving force, and thus ensuring the use effect of the microfluidic chip; and the driving mechanism and the counting mechanism are arranged on both sides of the valve mechanism, with a compact structure, small size, and easy to carry, and it is convenient for the operator to operate the driving mechanism and the valve mechanism at the same time while holding the negative pressure driving device, further improving the convenience of use.

[0011] In some embodiments, the driving mechanism includes a knob and a piston connected to the knob, the piston is the driving end of the driving mechanism, the knob is arranged at one end of the shell, the knob is threadedly connected to the outer wall of the vacuum chamber, and the piston moves along the depth direction of the vacuum chamber under the drive of the knob and changes the vacuum degree of the vacuum chamber.

[0012] By adopting the above technical solution, the rotational motion of the knob is converted into the linear motion of the piston in the vacuum chamber, thereby changing the vacuum degree of the vacuum chamber and realizing negative pressure drive. Compared with directly pushing the piston to move linearly, it is more labor-saving, convenient to use and has higher control accuracy.

[0013] In some embodiments, the valve mechanism includes a valve stem, wherein the valve stem is sequentially provided with a sealing portion and a communication portion along its axial direction, and the valve stem is movable relative to the housing to switch the sealing portion or the communication portion to correspond to the opening;

[0014] The sealing portion is used to isolate the opening from the vacuum chamber, and the communicating portion is used to communicate the opening with the vacuum chamber.

[0015] By adopting the above technical solution, the sealing part and the connecting part axially arranged on the valve stem cooperate with the valve stem to move relative to the shell, thereby realizing isolation and connection between the opening and the vacuum chamber, facilitating manual control by the operator, improving the ease of use of the negative pressure drive device, and having a simple structure, which can effectively control the volume of the negative pressure drive device, thereby improving the portability of the negative pressure drive device.

[0016] In some embodiments, the vacuum chamber is provided with an inlet and an outlet at one end away from the driving mechanism, and a channel is provided between the inlet and the outlet and the opening; the valve stem is provided on the channel, and,

[0017] When the sealing portion corresponds to the opening, the sealing portion blocks the channel so as to isolate the opening from the vacuum chamber;

[0018] When the communicating portion corresponds to the opening, the communicating portion communicates with the channel, so that the opening communicates with the vacuum chamber.

[0019] In some embodiments, the valve stem is plugged into the housing and can slide along the width direction of the housing;

[0020] The valve mechanism further includes a reset member and a limit block disposed in the housing;

[0021] The valve stem is provided with a first limiting structure and a second limiting structure spaced apart along its axial direction, and the limiting block is provided between the first limiting structure and the second limiting structure to limit the sliding of the valve stem between the first position and the second position;

[0022] When the valve stem is in the first position, the sealing portion corresponds to the opening;

[0023] When the valve stem is in the second position, the communication portion corresponds to the opening;

[0024] The restoring member abuts against the end of the valve stem and causes the valve stem to have a tendency to move toward the first position or the second position.

[0025] By adopting the above technical solution, the first limiting structure and the second limiting mechanism on the valve stem cooperate with the limiting block on the shell to realize the limitation and positioning of the movement position of the valve stem, thereby improving the reliability and convenience of use of the negative pressure drive device; the valve stem is reset by the reset member, further improving the convenience of use of the negative pressure drive device.

[0026] In some embodiments, the counting mechanism includes a counter and a linkage assembly, the counter is a mechanical counter, the linkage assembly includes a linkage rod, the two ends of the linkage rod are respectively connected to the driving mechanism and the counter, and the driving mechanism drives the counter to count through the linkage rod.

[0027] In some embodiments, a first sealing ring is provided on the circumference of the piston.

[0028] The above technical solution can improve the stability of the vacuum degree of the vacuum chamber, thereby ensuring that the driving device can provide reliable driving force, thereby ensuring the use effect of the microfluidic chip.

[0029] In some embodiments, the valve stem is sequentially provided with a plurality of second sealing rings along its axial direction, the communicating portion is located between two of the second sealing rings, and the sealing portion is located between the two second sealing rings.

[0030] The above technical solution can further improve the stability of the vacuum degree of the vacuum chamber and the stability of the negative pressure drive during the driving process, thereby ensuring that the driving device can provide reliable driving force and further ensuring the use effect of the microfluidic chip.

[0031] An embodiment of the present application also provides a microfluidic mixer, comprising a microfluidic chip and any of the negative pressure driving devices described above, wherein the microfluidic chip is arranged in the microfluidic chip accommodating area of ​​the negative pressure driving device, and the sample outlet of the microfluidic chip is arranged corresponding to the opening of the negative pressure driving device.

[0032] By adopting the above technical solution, through the cooperation of the negative pressure driving device and the microfluidic chip, the requirements for the operator and the operating environment are reduced, and the convenience of using the microfluidic technology is improved.

[0033] In some embodiments, the microfluidic chip includes at least two injection chambers and a reaction zone connected to the at least two injection chambers, the ends of the reaction zone are sequentially connected to a sample chamber and a buffer chamber, and the buffer chamber is connected to the sample outlet; and,

[0034] The bottom end of the sample chamber is communicated with the end of the reaction zone, the top end of the sample chamber is communicated with the top end of the buffer chamber, and the bottom end of the buffer chamber is communicated with the sample outlet.

[0035] By adopting the above technical solution, through the buffer chamber connected to the sample chamber and the setting of the inlet and outlet positions of the two, the risk of liquid moving under negative pressure drive entering the negative pressure drive device can be reduced, thereby ensuring the cleanliness of the negative pressure drive device and achieving reusability.

[0036] Other features and corresponding beneficial effects of the present application are described in the latter part of the specification, and it should be understood that at least some of the beneficial effects become obvious from the description in the specification of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a schematic structural diagram of the negative pressure drive device of this application;

[0038] Figure 2 This is a schematic diagram of the negative pressure drive device of the present application in use, wherein the microfluidic chip accommodating area is provided with a microfluidic chip;

[0039] Figure 3 This is a schematic cross-sectional view of the negative pressure drive device of the present application;

[0040] Figure 4 Schematic diagram of the structure of the microfluidic mixer in this application.

[0041] Description of reference numerals: 10, housing; 11, microfluidic chip accommodating area; 111, opening; 12, vacuum chamber; 121, inlet and outlet; 122, channel; 13, protective cover;

[0042] 20. Valve mechanism; 21. Valve stem; 211. Connecting portion; 212. Sealing portion; 213. First limiting structure; 214. Second limiting structure; 22. Resetting member; 23. Limiting block; 24. Second sealing ring;

[0043] 30. Driving mechanism; 31. Knob; 32. Piston; 33. First sealing ring;

[0044] 40. Counting mechanism; 41. Counter; 411. Counter display module; 42. Linkage rod;

[0045] 50. Microfluidic chip; 51. Injection chamber; 52. Reaction zone; 53. Sample chamber; 54. Buffer chamber. DETAILED DESCRIPTION

[0046] The following specific embodiments illustrate the implementation of the present application. Those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Although the description of the present application will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this application are limited to this implementation. On the contrary, the purpose of introducing the application in conjunction with the implementation is to cover other options or modifications that may be extended based on the claims of the present application. In order to provide an in-depth understanding of the present application, the following description will contain many specific details. The present application can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present application, some specific details will be omitted in the description. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other unless there is a conflict.

[0047] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0048] The following will clearly and completely describe the technical solution of this application in conjunction with the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of this application.

[0049] In the description of the present application, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description created by the present application, unless otherwise specified, "multiple" means two or more.

[0050] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0051] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0052] Example 1:

[0053] See Figure 1 , Figure 1 Schematic diagram of the structure of the negative pressure driving device in this embodiment; Figure 2 1 is a schematic diagram of the negative pressure driving device in use in this embodiment, wherein the microfluidic chip accommodating area 11 is provided with a microfluidic chip 50; Figure 3 2 is a schematic cross-sectional structural diagram of the negative pressure driving device in this embodiment, wherein the valve mechanism 20 is in a closed state, that is, the opening 111 is not connected to the vacuum chamber 12, and the vacuum chamber 12 forms a vacuum state.

[0054] An embodiment of the present application provides a negative pressure driving device for a microfluidic chip 50, including a shell 10 and a valve mechanism 20 and a driving mechanism 30 arranged on the shell 10, so as to integrate multiple operating components for driving the microfluidic chip 50, so that the microfluidic chip 50 can be directly driven by a single device, which is convenient to use.

[0055] A microfluidic chip accommodating area 11 is provided on the surface of the housing 10 , a vacuum chamber 12 is provided inside the housing 10 , and a driving end of the driving mechanism 30 is provided in the vacuum chamber 12 and can change the vacuum degree of the vacuum chamber 12 .

[0056] The microfluidic chip receiving area 11 is provided with an opening 111 in communication with the vacuum chamber 12. It is understood that the opening 111 is used to connect the drive port (usually also the sample outlet) of the microfluidic chip 50 placed in the microfluidic chip receiving area 11 to the vacuum chamber 12. It should be noted that the specific location of the opening 111 is generally matched with the microfluidic chip 50. In one embodiment, the opening 111 is directly connected to the drive port of the microfluidic chip 50, which is convenient to use. In other alternative embodiments, the opening 111 is connected to a hose and is connected to the drive port of the microfluidic chip 50 through the hose, thereby improving its versatility.

[0057] The valve mechanism 20 is disposed at the opening 111 , and the valve mechanism 20 is used to open and close the communication between the opening 111 and the vacuum chamber 12 . For example, when changing the vacuum degree of the vacuum chamber 12, the valve mechanism 20 can be first opened and cooperated with the driving mechanism 30 to evacuate the gas in the vacuum chamber 12 (it can be understood that, in order to prevent the microfluidic chip 50 from being affected, the microfluidic chip 50 is not placed at this time), and then the valve mechanism 20 is closed and cooperated with the driving mechanism 30 to change the vacuum degree of the vacuum chamber 12 with high precision. Specifically, the valve mechanism 20 is first opened to achieve communication between the vacuum chamber 12 and the opening 111, that is, the vacuum chamber 12 is connected to the outside, and the driving mechanism 30 is operated to move its driving end toward one end of the vacuum chamber 12 close to the opening 111 and abut against the inner wall thereof, thereby evacuating the gas in the vacuum chamber 12; then the valve mechanism 20 is closed to achieve isolation between the vacuum chamber 12 and the opening 111, that is, the vacuum chamber 12 is isolated from the outside, and the driving mechanism 30 is operated to move its driving end toward the other end of the vacuum chamber 12 and abut against the inner wall thereof, thereby increasing the vacuum degree of the vacuum chamber 12, that is, forming a negative pressure environment in the vacuum chamber 12. After the microfluidic chip 50 is placed in the microfluidic chip accommodating area 11 , the valve mechanism 20 can be opened to connect the vacuum chamber 12 with the interior of the microfluidic chip 50 , thereby achieving negative pressure driving of the liquid in the microfluidic chip 50 .

[0058] It should be noted that the driving end of the driving mechanism 30 abuts against the inner wall of one end of the vacuum chamber 12, thereby emptying the gas in the vacuum chamber 12, which means basically emptying it. Due to the inevitable gap between the driving end of the driving mechanism 30 and the inner wall and other conditions, absolute emptying cannot be achieved.

[0059] It should also be noted that when changing the vacuum degree of the vacuum chamber 12, the driving end of the driving mechanism 30 may not rest against the inner walls of the two ends of the vacuum chamber 12, so that the residual gas in the vacuum chamber 12 can pass through, making the subsequent vacuum degree adjustment more labor-saving and convenient to use, and the vacuum degree can be flexibly adjusted by changing the moving position of the driving end of the driving mechanism 30.

[0060] However, by placing the driving end of the driving mechanism 30 against the inner walls of the vacuum chamber 12 at both ends, quantitative measurement is facilitated, enabling relatively accurate determination of the vacuum level of the vacuum chamber 12 without the need for a vacuum measurement device (pre-testing can be performed to obtain a relatively accurate pressure over a certain number of uses), thereby ensuring the effectiveness of the microfluidic chip 50. This effectively controls the volume of the negative pressure drive device while providing a determinable negative pressure, thereby improving its portability. Furthermore, while achieving the same pressure, the volume of the vacuum chamber 12 in this embodiment is smaller, further effectively controlling the volume of the negative pressure drive device and improving its portability.

[0061] In one embodiment, the size of the microfluidic chip accommodating area 11 matches the size of the microfluidic chip 50, so that the microfluidic chip 50 can be embedded in the microfluidic chip accommodating area 11, and the microfluidic chip 50 is fixed to the negative pressure driving device.

[0062] It should be noted that the negative pressure driving device may have various models, and different models may be provided with different sizes of the microfluidic chip accommodating area 11 to match microfluidic chips 50 of different sizes.

[0063] In other alternative embodiments, the microfluidic chip accommodating area 11 is provided with elastic blocks so as to match microfluidic chips 50 of different sizes.

[0064] In one embodiment, a protective cover 13 is provided at one end of the housing 10 close to the driving mechanism 30 , and the protective cover 13 is provided on the outside of the driving mechanism 30 , thereby achieving a certain degree of protection for the driving mechanism 30 and reducing the risk of accidental touch.

[0065] In one embodiment, the driving mechanism 30 includes a knob 31 and a piston 32 connected to the knob 31. The piston 32 is the driving end of the driving mechanism 30. The knob 31 is arranged at one end of the shell 10. The knob 31 is threadedly connected to the outer wall of the vacuum chamber 12. Driven by the knob 31, the piston 32 moves along the depth direction of the vacuum chamber 12 and changes the vacuum degree of the vacuum chamber 12, that is, the rotational motion of the knob 31 is converted into a linear motion of the piston 32 in the vacuum chamber 12, thereby changing the vacuum degree of the vacuum chamber 12 and realizing negative pressure drive. Compared with directly pushing the piston 32 to move linearly, it is more labor-saving, easy to use, has higher control accuracy, is convenient for quantitative determination, and can ensure the state of the vacuum chamber 12 through the self-locking stroke of the thread, which is convenient for single-person operation.

[0066] In one embodiment, a first sealing ring 33 is provided around the circumference of the piston 32 to improve the stability of the vacuum level of the vacuum chamber 12, thereby ensuring that the drive device can provide reliable driving force, thereby ensuring the effectiveness of the microfluidic chip 50. Preferably, the first sealing ring 33 is a U-shaped ring to ensure both the reciprocating motion of the piston 32 and sealing performance.

[0067] In one embodiment, the valve mechanism 20 includes a valve stem 21, which is provided with a connecting portion 211 and a sealing portion 212 in sequence along its axial direction. The valve stem 21 can move relative to the housing 10 and switch the connecting portion 211 or the sealing portion 212 to correspond to the opening 111. The connecting portion 211 is used to connect the opening 111 with the vacuum chamber 12, and the sealing portion 212 is used to isolate the opening 111 from the vacuum chamber 12. In this manner, the opening 111 and the vacuum chamber 12 are isolated and connected, which facilitates manual control by the operator and improves the ease of use of the negative pressure drive device. In addition, the structure is simple, and the volume of the negative pressure drive device can be effectively controlled, thereby improving the portability of the negative pressure drive device.

[0068] In one embodiment, the valve stem 21 is provided with a plurality of second sealing rings 24 sequentially disposed along its axial direction, which further improves the sealing performance of the valve mechanism 20 and the stability of the negative pressure drive during actuation, thereby ensuring that the drive device can provide reliable driving force and, in turn, the performance of the microfluidic chip 50. Preferably, the second sealing ring 24 is an O-ring, which balances cost and sealing performance.

[0069] In one embodiment, the housing 10 has a cavity that matches the valve stem 21. The cavity is connected to the opening 111. One end of the valve stem 21 extends out of the cavity, and the valve stem 21 can move within the cavity to achieve opening and closing. The surface of the valve stem 21 and the cavity are adapted to be stepped, and the lower surface of the valve stem 21 is provided with a connecting portion 211, such as a groove. When the connecting portion 211 of the valve stem 21 intersects with the lower surface of the cavity, the valve mechanism 20 is in a closed state, as shown in FIG. Figure 3 As shown; when the connecting portion 211 of the valve stem 21 is opposite to the lower surface of the cavity, the valve mechanism 20 is in an open state. At this time, through the cooperation of the connecting portion 211 and the lower surface of the cavity, the connecting cross-section can be larger while ensuring the strength of the valve stem 21.

[0070] In one embodiment, the valve stem 21 is provided with three second sealing rings 24 in sequence along its axial direction, and a connecting portion 211 and a sealing portion 212 are provided between each two of them. Figure 3 When the valve mechanism 20 is in a closed state, the two second sealing rings 24 are respectively located on both sides of the communicating portion 211, and are located on the lower surface of the valve stem 21 and in conflict with the higher surface of the cavity, and one second sealing ring 24 is located on the higher surface of the valve stem 21 and in conflict with the lower surface of the cavity; when the valve mechanism 20 is in an open state, the middle second sealing ring 24 is out of contact with the higher surface of the cavity, and the communicating portion 211 is opposite to the lower surface of the cavity, thereby realizing communication between the vacuum chamber 12 and the opening 111.

[0071] In one embodiment, an inlet and outlet 121 is provided at one end of the vacuum chamber 12 away from the drive mechanism 30, and a channel 122 is provided between the inlet and outlet 121 and the opening 111. The valve stem 21 is provided on the channel 122. When the communication portion 211 corresponds to the opening 111, the communication portion 211 communicates with the channel 122, thereby connecting the opening 111 with the vacuum chamber 12. When the sealing portion 212 corresponds to the opening 111, the sealing portion 212 blocks the channel 122, thereby isolating the opening 111 from the vacuum chamber 12. The provision of the channel 122 allows for greater flexibility in the configuration of the valve stem 21 and its communication portion 211 and sealing portion 212.

[0072] In one embodiment, the valve stem 21 is arranged on the side of the channel 122 away from the opening 111, so that there is a certain distance between the vacuum chamber 12 and the accommodating chamber on the shell 10 for accommodating the valve stem 21, and the shell 10 can adopt a solid structure between the vacuum chamber 12 and the accommodating chamber, thereby improving the strength of the shell 10 and ensuring the service life of the negative pressure drive device.

[0073] In one embodiment, the valve stem 21 is plugged into the housing 10 and can slide along the width direction of the housing 10, which is convenient to use, so that the operator can control the valve stem 21 with the fingers of the same hand while holding the negative pressure drive device.

[0074] In one embodiment, the valve mechanism 20 further includes a limit block 23 disposed in the housing 10 .

[0075] The valve stem 21 is provided with a first limiting structure 213 and a second limiting structure 214 at intervals along its axial direction. The limiting block 23 is provided between the first limiting structure 213 and the second limiting structure 214 to limit the sliding of the valve stem 21 between the first position and the second position, thereby realizing the limitation and positioning of the movement position of the valve stem 21, thereby improving the reliability and convenience of use of the negative pressure drive device.

[0076] Furthermore, when the valve stem 21 is in the first position, the sealing portion 212 corresponds to the opening 111 ; and when the valve stem 21 is in the second position, the communicating portion 211 corresponds to the opening 111 .

[0077] In one embodiment, the first limiting structure 213, the second limiting structure 214 and the surface of the valve stem 21 form a groove of a certain length. The axial movement of the valve stem 21 causes the groove to move, so that the limiting block 23 abuts against the two ends of the groove, i.e., the first limiting structure 213 and the second limiting structure 214, to achieve limiting and positioning.

[0078] In other alternative embodiments, a limiting block is provided on the valve stem 21, and two matching limiting structures are provided in the housing 10 to achieve limiting and positioning.

[0079] In one embodiment, the valve mechanism 20 further includes a reset member 22 disposed within the housing 10. The reset member 22 abuts against the end of the valve stem 21 and causes the valve stem 21 to have a tendency to move toward the first position or the second position. This allows the valve stem 21 to automatically reset when it is out of operator control, further improving the ease of use of the negative pressure drive device.

[0080] In one embodiment, the valve stem 21 has a tendency to move toward the first position, allowing the negative pressure drive device to automatically return to a sealed state, preventing it from being connected to the outside for a long time when not in use, thereby causing external contamination to enter the interior and affect subsequent use. In this case, the return member 22 can be a tension spring.

[0081] In one embodiment, the valve stem 21 has a tendency to move toward the second position, allowing the vacuum drive device to communicate with the outside under normal conditions. This prevents changes in the vacuum level of the vacuum chamber 12 due to thermal expansion and contraction, which could affect the sealing performance of the vacuum drive device, thereby ensuring a constant vacuum level during subsequent use. In this case, the return member 22 may be a spring.

[0082] Since the internal part of the negative pressure driving device will inevitably wear out after long-term use, and a sealing ring is usually provided inside, which has a service life, the sealing performance will be weakened, affecting the accuracy of the negative pressure formed, and during use, pollutants will inevitably enter the interior, and the accumulation will increase after long-term use, thereby increasing the risk of pollutants entering the microfluidic chip 50 during subsequent use. Therefore, in order to ensure the effectiveness of use, the negative pressure driving device is preferably used within the specified number of times and is scrapped regularly.

[0083] In order to allow the operator to clearly know the number of uses, in one embodiment, the negative pressure drive device further includes a counting mechanism 40 , and the drive mechanism 30 and the counting mechanism 40 are respectively arranged on both sides of the valve mechanism 20 .

[0084] The counting mechanism 40 is in transmission connection with the driving mechanism 30 and is used to count the number of times the driving mechanism 30 has been actuated, that is, the number of times the driving device has been used. This can be either a positive number or a remaining number, thereby prompting the operator to use the device within the specified number of times, ensuring that the driving device can provide reliable driving force, and thus ensuring the effective use of the microfluidic chip 50. Furthermore, the driving mechanism 30 and the counting mechanism 40 are disposed on either side of the valve mechanism 20, resulting in a compact structure and small size, making them easy to carry. Furthermore, the operator can easily operate the driving mechanism 30 and the valve mechanism 20 simultaneously while holding the negative pressure driving device, further improving ease of use.

[0085] In one embodiment, the counting mechanism 40 includes a counter 41 and a linkage assembly. Preferably, the counter 41 is a mechanical counter 41, which does not require power supply, is easy to use, and has low cost. The linkage assembly includes a linkage rod 42, the two ends of which are respectively connected to the drive mechanism 30 and the counter 41, and the drive mechanism 30 drives the counter 41 to count through the linkage rod 42. For example, the linkage rod 42 is movably connected to the knob 31 and can move linearly synchronously with the rotation of the knob 31. The linkage rod 42 moves linearly back and forth once, pushing the counter 41 to count once, that is, the valve mechanism 20 counts once each time it is opened and closed. The counter 41 that cooperates with the linkage rod 42 can be implemented using existing technology, such as a counter 41 driven by a ratchet.

[0086] It is understandable that the display module of the counting mechanism 40 , that is, the counter display module 411 , can be provided on the surface of the housing 10 , so as to facilitate real-time visualization.

[0087] Example 2:

[0088] See Figure 4 , Figure 4 Schematic diagram of the structure of the microfluidic mixer in this embodiment.

[0089] The present application also provides a microfluidic mixer comprising a microfluidic chip 50 and the negative pressure drive device of Example 1. The microfluidic chip 50 is disposed in the microfluidic chip accommodating area 11 of the negative pressure drive device, and the sample outlet of the microfluidic chip 50 is disposed correspondingly to the opening 111 of the negative pressure drive device. This allows the microfluidic chip 50 to be directly driven by the negative pressure drive device, reducing the requirements for the operator and operating environment and improving the convenience of using microfluidic technology.

[0090] In one embodiment, the microfluidic chip 50 includes at least two injection chambers 51 and a reaction zone 52 connected to the at least two injection chambers 51, the end of the reaction zone 52 is connected to the sample chamber 53 and the buffer chamber 54 in sequence, and the buffer chamber 54 is connected to the sample outlet; and the bottom end of the sample chamber 53 is connected to the end of the reaction zone 52, the top end of the sample chamber 53 is connected to the top end of the buffer chamber 54, and the bottom end of the buffer chamber 54 is connected to the sample outlet, which can reduce the risk of liquid moving under negative pressure drive entering the negative pressure drive device, thereby ensuring the cleanliness of the negative pressure drive device, achieving reusability and reducing the risk of the generated sample entering the negative pressure drive device and being lost.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A negative pressure driving device for a microfluidic chip, characterized in that: It includes a housing and a valve mechanism arranged on the housing, and a driving mechanism and a counting mechanism are respectively arranged on both sides of the valve mechanism. The shell surface is provided with a microfluidic chip accommodating area, the shell interior is provided with a vacuum cavity, the driving end of the driving mechanism is provided in the vacuum cavity and can change the vacuum degree of the vacuum cavity; The microfluidic chip accommodating area is provided with an opening communicating with the vacuum chamber, the valve mechanism is provided at the opening, and the valve mechanism is used to open and close the communication between the opening and the vacuum chamber; The counting mechanism is in transmission connection with the driving mechanism, and the counting mechanism is used to count the number of driving times of the driving mechanism.

2. The negative pressure driving device for a microfluidic chip according to claim 1, characterized in that: The driving mechanism includes a knob and a piston connected to the knob. The piston is the driving end of the driving mechanism. The knob is arranged at one end of the shell. The knob is threadedly connected to the outer wall of the vacuum chamber. Driven by the knob, the piston moves along the depth direction of the vacuum chamber and changes the vacuum degree of the vacuum chamber.

3. The negative pressure driving device for a microfluidic chip according to claim 1, characterized in that: The valve mechanism includes a valve stem, which is provided with a sealing portion and a communication portion in sequence along its axial direction, and the valve stem can move relative to the housing and switch the sealing portion or the communication portion to correspond to the opening; The sealing portion is used to isolate the opening from the vacuum chamber, and the communicating portion is used to communicate the opening with the vacuum chamber.

4. The negative pressure driving device for a microfluidic chip according to claim 3, characterized in that: The vacuum chamber is provided with an inlet and an outlet at one end away from the driving mechanism, and a channel is provided between the inlet and the outlet and the opening; the valve stem is provided on the channel, and, When the sealing portion corresponds to the opening, the sealing portion blocks the channel so as to isolate the opening from the vacuum chamber; When the communicating portion corresponds to the opening, the communicating portion communicates with the channel, so that the opening communicates with the vacuum chamber.

5. The negative pressure driving device for a microfluidic chip according to claim 4, characterized in that: The valve stem is plugged into the housing and can slide along the width direction of the housing; The valve mechanism further includes a reset member and a limit block disposed in the housing; The valve stem is provided with a first limiting structure and a second limiting structure spaced apart along its axial direction, and the limiting block is provided between the first limiting structure and the second limiting structure to limit the sliding of the valve stem between the first position and the second position; When the valve stem is in the first position, the sealing portion corresponds to the opening; When the valve stem is in the second position, the communication portion corresponds to the opening; The restoring member abuts against the end of the valve stem and causes the valve stem to have a tendency to move toward the first position or the second position.

6. The negative pressure driving device for a microfluidic chip according to claim 1, characterized in that: The counting mechanism includes a counter and a linkage component. The counter is a mechanical counter. The linkage component includes a linkage rod. The two ends of the linkage rod are respectively connected to the driving mechanism and the counter, and the driving mechanism drives the counter to count through the linkage rod.

7. The negative pressure driving device for a microfluidic chip according to claim 2, characterized in that: A first sealing ring is provided on the circumference of the piston.

8. The negative pressure driving device for a microfluidic chip according to claim 3, characterized in that: The valve stem is sequentially provided with a plurality of second sealing rings along its axial direction, the communicating portion is located between two of the second sealing rings, and the sealing portion is located between the two of the second sealing rings.

9. A microfluidic mixer, characterized in that It comprises a microfluidic chip and a negative pressure driving device as described in any one of claims 1 to 8, wherein the microfluidic chip is arranged in the microfluidic chip accommodating area of ​​the negative pressure driving device, and the sample outlet of the microfluidic chip is arranged corresponding to the opening of the negative pressure driving device.

10. The microfluidic mixer according to claim 9, characterized in that The microfluidic chip comprises at least two injection chambers and a reaction zone connected to the at least two injection chambers, the ends of the reaction zone are sequentially connected to a sample chamber and a buffer chamber, and the buffer chamber is connected to the sample outlet; and The bottom end of the sample chamber is communicated with the end of the reaction zone, the top end of the sample chamber is communicated with the top end of the buffer chamber, and the bottom end of the buffer chamber is communicated with the sample outlet.

Images