Pressing pump and micro-fluidic chip

Abstract

The invention discloses a pressing pump and a micro-fluidic chip, and belongs to the technical field of microfluidics, the pressing pump comprises a pressing air bag, a brake chamber and two one-way valves; in the brake chamber and the one-way valve, the fluid layer and the gas layer are separated by an elastic film and a double-sided adhesive film which is attached to the elastic film and is provided with a circular area through cutting, and the other film layers are thermoplastic material films; in the one-way valve, a layer of thermoplastic material film below the elastic film is also cut into a circular area, and the two cutting areas are the same in size and are both located under the cylindrical micro valve; in the brake chamber, circular areas are also cut on the thermoplastic material films above and below the elastic film, and the three cutting areas are the same in size and position; the fluid layer of the first one-way valve, the fluid layer of the brake chamber and the fluid layer of the second one-way valve are connected in sequence; the first one-way valve and the gas layer of the brake cavity are connected with the pressing air bag. The manufacturing time consumption, the manufacturing cost and the manufacturing complexity of the pressing pump can be reduced.

Description

Technical Field

[0001] The present invention belongs to the field of microfluidics technology, and more specifically, relates to a pressure pump and a microfluidics chip. Background Art

[0002] The progress of microfluidic technology has made the driving and control of microfluidics more flexible, accurate and convenient, and promoted the development of instant diagnosis, biochemical analysis, cell culture and other related fields. Traditional fluid driving methods rely on the support of expensive devices and require traditional fluid pumps such as peristaltic pumps and syringe pumps. Although they have the advantages of precise adjustment of flow rate and flow rate, they are not conducive to the miniaturization of microfluidic devices and their application in the field of instant diagnosis. As the core and typical component of microfluidic systems, micropumps have attracted widespread attention due to their advantages such as miniaturization and integration. It is of great significance to develop high-performance micropumps with smaller size, lower cost and easier processing.

[0003] Micropumps are divided into two categories: those that require external power and those that do not. Micropumps that require external power are driven by a small external power source or actuator platform, such as small peristaltic pumps, electrowetting, electroosmotic pumps, centrifugal pumps and magnetic pumps. Micropumps that require external power are smaller in size than traditional fluid pumps and can be more integrated, but their reliance on external power and actuator platforms greatly limits their use in environments with limited conditions. Micropumps that do not require external power can be driven spontaneously by some physical principles such as capillary action, siphon action, osmotic pressure, gravity, etc., or by a combination of manpower and specific mechanical structures, such as manually driven syringe pumps, manual centrifugal pumps, and finger-pressed pumps, to achieve liquid driving. Because they are free from reliance on external power and actuator platforms, micropumps that do not require external power have a wide range of applications in the field of instant diagnosis.

[0004] The finger-press pump is a typical micropump that does not require an external power supply. It is small in size, highly editable, and can be integrated with the microfluidic system without the need for cumbersome connections, which reduces the risk of contamination and makes the application prospects of the microfluidic system more diverse.

[0005] The finger press pump includes a button, a deformable chamber and various microvalves. By pressing and releasing the button, the deformable chamber can be deformed regularly. By combining with the microvalve, the fluid can be driven. The most classic finger press pump is made based on PDMS material, because PDMS, as an elastic material, is suitable for making deformable chambers and microvalves, and has high processing precision and strong structural stability. A press-type microfluidic chip, microfluidic device and bacterial detection method published by Tsinghua University and Shenzhen Green Poetry Source Biotechnology Co., Ltd. (application publication number: CN114480096A), and a microfluidic chip and microbial detection method published by China Agricultural University (application publication number: CN114225978A), both use classic soft lithography methods to process and manufacture finger press pumps and press chips. Figure 1 As shown in the figure, in the finger press pump made of PDMS material, each layer of material is made of PDMS material. In order to avoid the adhesion between the microvalve and the elastic membrane below, soft photolithography PDMS needs to be processed with plasma to assemble the multilayer structure, which is easy to damage the structure of the microvalve by mistake and the valve body is also easy to damage during the demolding process (Lab Chip, 2024, 24, 843-853). Therefore, it is difficult to achieve rapid batch production of press pumps by soft photolithography PDMS. In addition, due to the poor rigidity of PDMS, when the deformable chamber is deformed, its top and bottom membranes may also be deformed under the influence of the elastic membrane, affecting the structural stability and the accuracy of liquid pumping.

[0006] Thermoplastic material PMMA can be manufactured in large quantities at low cost through reproducible and direct manufacturing technologies such as injection, compression molding, casting, hot pressing, micro-milling, laser ablation, etc., and can replace PDMS in some microfluidic devices. Some studies have used PMMA and partially blocked pressure-sensitive adhesive to make a finger press pump (Lab Chip, 2023, 23, 4579-4591), and its structure is as follows Figure 2 As shown. Compared with the finger-pressed pump made of PDMS, the top and bottom membranes made of PMMA have better rigidity and do not require plasma treatment, which reduces the production time, production cost, and production complexity. However, some small units still need to be additionally processed and modified with blocking agents, which is not simple enough and not suitable for rapid batch production.

[0007] In general, the existing finger press pump has a long production time, high production cost and high production complexity due to its structural limitations. Summary of the invention

[0008] In view of the defects and improvement needs of the prior art, the present invention provides a pressing pump and a microfluidic chip, the purpose of which is to reduce the manufacturing time, manufacturing cost and manufacturing complexity by improving the structure of a finger pressing pump.

[0009] To achieve the above object, according to one aspect of the present invention, a pressing pump is provided, comprising: a pressing airbag, a brake chamber and two one-way valves; the two one-way valves are respectively a first one-way valve and a second one-way valve;

[0010] The one-way valve comprises: a first thermoplastic material film, a second thermoplastic material film, a first elastic film, a first double-sided adhesive film which are attached in sequence from bottom to top, a third thermoplastic material film fixed on the first double-sided adhesive film by a first support column, and a cylindrical microvalve whose upper bottom surface is attached to the lower surface of the third thermoplastic material film; the cylindrical microvalve is made of thermoplastic material, and the height of the first support column is not less than the height of the cylindrical microvalve; the circular area with a radius of r1 located directly below the cylindrical microvalve in the first double-sided adhesive film and the second thermoplastic material film is cut; the structure above the first elastic film forms a fluid layer of the one-way valve, and the structure below the first elastic film forms a gas layer of the one-way valve;

[0011] The brake chamber comprises: a fourth thermoplastic film, a fifth thermoplastic film, a second elastic film, a second double-sided adhesive film, which are attached in sequence from bottom to top, a sixth thermoplastic film fixed on the second double-sided adhesive film by a second support column, and a seventh thermoplastic film attached to the upper surface of the sixth thermoplastic film; circular areas with a radius of r2 at the same position in the fifth thermoplastic film, the second double-sided adhesive film and the sixth thermoplastic film are all cut; the structure above the second elastic film forms a fluid layer of the brake chamber, and the structure below the second elastic film forms a gas layer of the brake chamber;

[0012] The fluid layer of the first one-way valve, the fluid layer of the brake chamber and the fluid layer of the second one-way valve are connected in sequence, the fluid layer inlet of the first one-way valve serves as the fluid inlet of the pressing pump, and the fluid layer outlet of the second one-way valve serves as the fluid outlet of the pressing pump; the cut circular areas in the gas layers of the first one-way valve and the brake chamber are connected to the pressing airbag through the gas path microchannel;

[0013] Among them, r0≤r1≤r2, r0 is the bottom radius of the cylindrical valve.

[0014] Further, the materials of the first thermoplastic material film, the second thermoplastic material film, the third thermoplastic material film, the fourth thermoplastic material film, the fifth thermoplastic material film, the sixth thermoplastic material film, the seventh thermoplastic material film and the cylindrical microvalve are all PMMA.

[0015] Furthermore, the first elastic film and the second elastic film are both made of silicone.

[0016] According to another aspect of the present invention, there is provided a microfluidic chip, comprising: N1 pressing pumps; the pressing pumps are the above-mentioned pressing pumps provided by the present invention;

[0017] The fluid inlet and fluid outlet of each pressing pump are independent of each other, and the pressing airbags of N1 pressing pumps are the same pressing airbag; N1≥2.

[0018] According to one aspect of the present invention, there is provided a microfluidic chip, comprising: N2 pressing pumps, the pressing pump being the above-mentioned pressing pump provided by the present invention;

[0019] Among them, the fluid inlets of each pressing pump are independent of each other, the fluid outlets of N2 pressing pumps are connected to one point, and the pressing airbags of the N2 pressing pumps are the same pressing airbag; N2≥2.

[0020] According to another aspect of the present invention, there is provided a microfluidic chip, comprising: the above-mentioned pressing pump and liquid separation module provided by the present invention;

[0021] The liquid separation module includes an inlet flow channel, a liquid separation chamber and N3 outlet flow channels; one end of the inlet flow channel is connected to the liquid separation chamber, and the other end is connected to the fluid outlet of the pressing pump as the inlet of the liquid separation module; one end of the outlet flow channel is connected to the liquid separation chamber, and the other end is an outlet of the liquid separation module;

[0022] Among them, N3≥2.

[0023] According to another aspect of the present invention, there is provided a microfluidic chip, comprising: N4 liquid storage chambers and N4 pressing pumps; the pressing pumps are the above-mentioned pressing pumps provided by the present invention;

[0024] The fluid layers of N4 pressing pumps are connected in sequence, and the fluid outlet of the last pressing pump is connected to the fluid inlet of the first pressing pump. A liquid storage chamber is provided at the connection of the fluid layers of adjacent pressing pumps; the pressing airbags of adjacent pressing pumps are different;

[0025] Among them, N4≥3.

[0026] According to another aspect of the present invention, there is provided a microfluidic chip, comprising: a reaction chamber and N5 pressing pumps; the pressing pump is the above-mentioned pressing pump provided by the present invention;

[0027] The fluid inlet and the pressing airbag of each pressing pump are independent of each other, and the fluid outlets of N5 pressing pumps are all connected to the reaction chamber;

[0028] Among them, N3≥2.

[0029] According to another aspect of the present invention, a microfluidic chip is provided, comprising: a concentration gradient generating module and two pressing pumps; the pressing pump is the above-mentioned pressing pump provided by the present invention;

[0030] A Christmas tree structure fluid microchannel is provided in the concentration gradient generation module; the Christmas tree structure fluid microchannel includes multiple layers of longitudinal microchannels and multiple layers of transverse microchannels; the number of the first layer of longitudinal microchannels is 2, and the number of each subsequent layer of longitudinal microchannels is 1 more than the number of the previous layer of longitudinal microchannels; the transverse microchannel is provided at the junction of two adjacent layers of longitudinal microchannels, and is connected to the adjacent longitudinal microchannels;

[0031] The fluid inlets of the pressing pumps are independent of each other, and the fluid outlets of the two pressing pumps are respectively connected to two longitudinal microchannels located in the first layer of the concentration gradient generation module, and the pressing airbags of the two pressing pumps are the same pressing airbag.

[0032] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects:

[0033] (1) The press pump provided by the present invention utilizes thermoplastic materials to manufacture the one-way valve and the microvalve structure and the rigid structure in the brake chamber, which can prevent the top film and the bottom film from being deformed when the elastic film is deformed; by using a non-sticky elastic film and arranging a layer of specially cut double-sided adhesive film thereon, the deformation area of ​​the silicone film can be controlled while ensuring the structural stability, and the elastic film will not adhere to the thermoplastic material structure when it is deformed, so there is no need for modification, no need to process small units separately, and no need for precise alignment, which greatly reduces the production cost and processing complexity of the press pump, and also reduces the production time.

[0034] (2) The present invention combines the provided press pump with the microfluidic channel to form different microfluidic structures, which can realize complex functions. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the structure, elastic membrane manufacturing method and working process of the existing finger press pump made based on PDMS;

[0036] Figure 2 It is a schematic diagram of the structure, elastic film manufacturing method and working process of the existing PMMA-based finger press pump;

[0037] Figure 3 A schematic diagram of the structure of a one-way valve and a brake chamber in a press pump provided in Example 1 of the present invention, a method for manufacturing an elastic membrane, and a working process;

[0038] Figure 4 Schematic diagram of a pressing pump structure and a pumping process thereof provided in Example 1 of the present invention; wherein (a) is a schematic diagram of the pressing pump structure, (b) is a plan schematic diagram of the pumping process, and (c) is a three-dimensional schematic diagram of the pumping process;

[0039] Figure 5 A schematic diagram of a pressing test provided in Example 1 of the present invention; wherein (a) is a comparison diagram of the pumping effects of a pressing pump operated by two different pressing methods, (b) is a result of multiple tests on the pumping effects of the pressing pump, (c) is a diagram showing the pumping effects of pressing pumps of different brake chamber sizes, (d) is a diagram showing the relationship between the pumping effect of the pressing pump and the square of the radius of the brake chamber, (e) is a schematic diagram showing the reciprocating flow of liquid during the pumping process of the pressing pump, and (f) is an actual test result of the liquid pumping distance during the operation of the pressing pump;

[0040] Figure 6 A schematic diagram showing the relationship between the number of presses and the volume of pumped liquid provided in Example 1 of the present invention;

[0041] Figure 7 Schematic diagram of a microfluidic chip provided in Example 2 of the present invention; wherein (a) is a schematic diagram of the structure of the microfluidic chip, and (b) is a schematic diagram of liquid release in the microfluidic chip;

[0042] Figure 8 Schematic diagram of a microfluidic chip provided in Example 3 of the present invention; wherein (a) is a schematic diagram of the structure of the microfluidic chip, and (b) is a schematic diagram of liquid release in the microfluidic chip;

[0043] Fig. 9 Schematic diagram of a microfluidic chip provided in Example 4 of the present invention; wherein (a) is a schematic diagram of the structure of the microfluidic chip, and (b) is a schematic diagram of liquid release in the microfluidic chip;

[0044] Fig.10 Schematic diagram of a microfluidic chip provided in Example 5 of the present invention; wherein (a) is a schematic diagram of the structure of the microfluidic chip, and (b) is a schematic diagram of liquid release in the microfluidic chip;

[0045] Fig.11 Schematic diagram of a microfluidic chip provided in Example 6 of the present invention; wherein (a) is a schematic diagram of the structure of the microfluidic chip, and (b) is a schematic diagram of liquid release in the microfluidic chip;

[0046] Fig.12 Schematic diagram of the microfluidic chip provided in Example 7 of the present invention; wherein (a) is a schematic diagram of the three-dimensional structure of the microfluidic chip, (b) is a schematic diagram of the dimensions of the microfluidic chip, (c) is a schematic diagram of the operation of generating a concentration gradient, (d) is a schematic diagram of the result of using Comsol simulation to generate a gradient; (e) is a schematic diagram of the actual generated concentration gradient result;

[0047] In all drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0048] 1-first thermoplastic film, 2-second thermoplastic film, 3-first elastic film, 4-first double-sided adhesive film, 4-first double-sided adhesive film, 5-cylindrical microvalve, 6-third thermoplastic film, 7-fourth thermoplastic film, 8-fifth thermoplastic film, 9-second elastic film, 10-second double-sided adhesive film, 11-sixth thermoplastic film, 12-seventh thermoplastic film. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0050] It should be noted that, in the description of the present invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc. indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, it should be noted that, in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal connection of two elements. The terms "first", "second", etc. (if any) in the present invention and the drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0051] In order to solve the technical problems that the existing finger press pump needs special modification treatment during production due to structural limitations, resulting in long production time, high production cost and high production complexity, the present invention proposes a new press pump, which improves the one-way valve structure of the press pump and the elastic membrane layer structure in the brake chamber, and improves the original single-layer elastic and sticky membrane layer into a structure composed of a non-sticky elastic membrane layer and a specially cut double-sided sticky membrane layer. In this structure, the elastic membrane layer will not adhere to other structures when deformed. Therefore, there is no need for modification, no need to individually process small units, and no need for precise alignment. It can be quickly mass-produced with low production cost.

[0052] Based on the proposed new press pump, the present invention also designs a variety of microfluidic structures composed of press pumps and microchannels, which can realize more complex liquid operation functions, meet different microfluidic application requirements, and develop the application potential of press pumps.

[0053] The following are examples.

[0054] Embodiment 1:

[0055] A compression pump, such as Figure 3 and Figure 4 As shown, it includes: a pressing airbag, a braking chamber and two one-way valves; the two one-way valves are respectively a first one-way valve and a second one-way valve.

[0056] In order to prevent the top membrane and the bottom membrane from being deformed when the elastic membrane layer is deformed, in this embodiment, a thermoplastic material with good rigidity is used to make the one-way valve and the microvalve structure and the rigid structure in the brake chamber.

[0057] like Figure 3 As shown, in this embodiment, the one-way valve includes: a first thermoplastic material film 1, a second thermoplastic material film 2, a first elastic film 3, a first double-sided adhesive film 4 which are attached in sequence from bottom to top, a third thermoplastic material film 6 fixed to the first double-sided adhesive film 4 by a first support column, and a cylindrical microvalve 5 whose upper bottom surface is attached to the lower surface of the third thermoplastic material film 6; the cylindrical microvalve 5 is made of thermoplastic material, and the height of the first support column is not less than the height of the cylindrical microvalve 5; the circular area with a radius of r1 located directly below the cylindrical microvalve 5 in the first double-sided adhesive film 4 and the second thermoplastic material film 2 is cut; the structure above the first elastic film 3 forms the fluid layer of the one-way valve, and the structure below the first elastic film 3 forms the gas layer of the one-way valve;

[0058] like Figure 3 As shown, in this embodiment, the brake chamber includes: a fourth thermoplastic film 7, a fifth thermoplastic film 8, a second elastic film 9, a second double-sided adhesive film 10 attached in sequence from bottom to top, a sixth thermoplastic film 11 fixed on the second double-sided adhesive film by a second support column, and a seventh thermoplastic film 12 attached to the upper surface of the sixth thermoplastic film 11; circular areas with a radius of r2 at the same position in the fifth thermoplastic film 8, the second double-sided adhesive film 10 and the sixth thermoplastic film 11 are all cut; the structure above the second elastic film 9 forms a fluid layer of the brake chamber, and the structure below the second elastic film 9 forms a gas layer of the brake chamber;

[0059] like Figure 4As shown in (a), the fluid layer of the first one-way valve, the fluid layer of the brake chamber, and the fluid layer of the second one-way valve are connected in sequence, the fluid layer inlet of the first one-way valve serves as the fluid inlet of the pressing pump, and the fluid layer outlet of the second one-way valve serves as the fluid outlet of the pressing pump; the cut circular areas in the gas layers of the first one-way valve and the brake chamber are connected to the pressing airbag through the gas path microchannel;

[0060] Among them, r0≤r1≤r2, r0 is the bottom radius of the cylindrical valve.

[0061] In practical applications, the thermoplastic material film and the cylindrical microvalve can be made of thermoplastic materials such as PMMA and PC. Optionally, PMMA material is specifically used in this embodiment; the elastic film and the double-sided adhesive film can be made of elastic materials and double-sided adhesive materials according to actual needs. Optionally, in this embodiment, the elastic film is made of silicone, and the double-sided adhesive film is made of commonly used double-sided adhesive. The size parameters of each film layer are as follows:

[0062] In the one-way valve, the bottom layer of the first thermoplastic material film is 0.4 mm thick PMMA, the second thermoplastic material film is 0.4 mm thick PMMA with a circular area of ​​1 mm radius cut out, the first elastic film is 0.1 mm thick silicone film, the first double-sided adhesive film is a double-sided adhesive with a circular area of ​​1 mm radius cut out, the radius of the cylindrical microvalve is 1 mm, the valve width is 1 mm, and it is cut from 0.4 mm thick PMMA, and the top layer of the third thermoplastic material film is 0.4 mm thick PMM;

[0063] In the brake chamber, the fourth thermoplastic material film at the bottom layer is PMMA with a thickness of 0.4 mm, the fifth thermoplastic material film is PMMA with a circular area cut out with a radius of 2 mm and a thickness of 0.4 mm, the second elastic film is a silicone film with a thickness of 0.1 mm, the second double-sided adhesive film is a double-sided adhesive film with a circular area cut out with a radius of 2 mm, the sixth thermoplastic material film is PMMA with a circular area cut out with a radius of 2 mm and a thickness of 0.4 mm, and the seventh thermoplastic material film at the top layer is PMMA with a thickness of 0.4 mm.

[0064] In the one-way valve and the brake chamber, the bottom layer is closed, and the cut circular area in the gas layer forms a closed gas cavity with the upper elastic membrane and the lower thermoplastic material membrane. By controlling the air pressure in the gas cavity, the deformation of the elastic membrane can be controlled. Figure 3 As shown in the figure, when the pressure airbag is pressed, the air pressure in the gas cavity of the one-way valve increases, the elastic membrane passes through the cut area in the double-sided adhesive and deforms upward and contacts the bottom surface of the cylindrical microvalve, blocking the fluid layer, so that the one-way valve and the fluid cannot pass through the fluid layer; when the pressure airbag is released, negative pressure is formed in the gas cavity of the one-way valve, the elastic membrane deforms downward, the fluid layer is connected, the one-way valve is opened, and the fluid can pass through the fluid layer smoothly. Similarly, Figure 3 As shown, when the pressing airbag is pressed, the air pressure in the gas cavity in the brake chamber increases, the elastic membrane passes through the cutting area in the double-sided adhesive and deforms upward and contacts the lower bottom surface of the seventh thermoplastic material film on the top layer, and the fluid layer is blocked; when the pressing airbag is released, negative pressure is formed in the gas cavity in the brake chamber, the elastic membrane deforms downward, the fluid layer is conductive, and the fluid can pass through the fluid layer smoothly.

[0065] In this embodiment, while using a silicone film as an elastic film, a layer of specially cut double-sided tape is set on it. While ensuring the stability of the structure, the deformation area of ​​the silicone film can be controlled, and the silicone film will not adhere to PMMA, and does not require modification, separate processing of small units, and precise alignment, which greatly reduces the production cost and processing complexity of the press pump. Based on the press pump structure provided in this embodiment, a laser cutting machine is first used to cut and process each layer of material according to the structure designed in the drawing, and then assembled in sequence. After the assembly is completed, hot pressing bonding can be performed. A set of finger press pumps can be processed within 10 minutes, while traditional soft lithography technology often requires a production cycle of several days. In comparison, this embodiment greatly shortens the production cycle.

[0066] The pressing pump provided in this embodiment has a pumping process as follows: Figure 4 As shown in (b) and (c), when the pressing airbag is released from the pressed state, the elastic membrane in the first one-way valve and the brake chamber are deformed downward, and the elastic membrane in the second one-way valve is deformed upward, causing the second one-way valve to close. After the fluid is pumped from the inlet to the second one-way valve, it will not be able to continue to be pumped forward, but will be temporarily stored in the brake chamber; at this time, when the pressing airbag is pressed, the elastic membrane in the first one-way valve and the brake chamber are deformed upward, the first one-way valve is closed, and the elastic membrane in the second one-way valve is deformed downward, and the second one-way valve is opened; while the elastic membrane in the brake chamber is deformed upward, the temporarily stored fluid therein will be pumped to both sides. Since the first one-way valve is closed, the fluid will be pumped forward through the second one-way valve. By alternately pressing and releasing the pressing airbag, the fluid can be continuously pumped from the fluid inlet to the fluid outlet through the above process.

[0067] It should be noted that the material selection and size parameters of the above-mentioned film layers are only exemplary descriptions and should not be understood as the only limitation of the present invention. In practical applications, the thermoplastic film can also be made of other thermoplastic materials other than PMMA, and the elastic film can also be made of other elastic materials that will not adhere to the upper and lower layer structures. In addition, the above-mentioned parameters can be flexibly adjusted according to the actual fluid pumping needs. Usually, the size of the cutting area in the brake chamber is larger than the size of the cutting area in the one-way valve to ensure sufficient fluid temporary storage capacity.

[0068] In order to further verify the pumping performance of the pressing pump provided in this embodiment, this embodiment tests two pressing methods. The test results are as follows: Figure 5 As shown, pressing method 1 is a random pressing method. Each time the airbag is pressed, it is not required to press to the maximum deformation range. Only fingers are used for natural pressing. Figure 5 In the figure, (a) is a comparison of the pumping effects of the press pump using two different pressing methods, (b) is the result of multiple tests on the pumping effect of the press pump, (c) is the pumping effect of the press pump with different brake chamber sizes, (d) is a relationship diagram between the pumping effect of the press pump and the square of the brake chamber radius, (e) is a schematic diagram of the reciprocating flow of the liquid during the pumping process of the press pump, and (f) is the actual test result of the liquid pumping distance during the operation of the press pump. Pressing method 2 controls the upper and lower surfaces of the airbag to contact each time the airbag is pressed, so as to achieve the maximum deformation range as much as possible. Figure 5 The results shown show that when pressing method 2 is used for pressing, a more stable pumping effect is achieved.

[0069] This embodiment further tests the relationship between the number of presses and the volume of pumped liquid. The results are as follows: Figure 6 As shown, it can be seen that the number of presses of the press pump provided in this embodiment shows an obvious linear relationship between the volume of the pumped liquid and the number of presses, which indicates that the press pump proposed in this embodiment has the ability to stably pump liquid and can be used as a driving force in a microfluidic chip to perform liquid manipulation and other complex functions.

[0070] In general, the press pump provided in this embodiment can achieve accurate and convenient liquid pumping while reducing the production cost and processing complexity of the press pump and greatly shortening the production cycle.

[0071] Embodiment 2:

[0072] A microfluidic chip, such as Figure 7 As shown in (a), it includes: 5 pressing pumps; the pressing pumps are the pressing pumps provided in the above embodiment 1;

[0073] The fluid inlet and fluid outlet of each pressing pump are independent of each other. Accordingly, the microfluidic chip has 5 fluid inlets and 5 fluid outlets. The pressing airbags of the 5 pressing pumps are the same pressing airbag.

[0074] The microfluidic chip provided in this embodiment is composed of 5 push pumps connected in parallel, and the fluid layers in the 5 push pumps are connected in parallel. At the same time, the 5 push pumps in the microfluidic chip are controlled by the same push airbag, so that 5-way fluid pumping can be achieved at the same time through one operation. Figure 7As shown in (b), "1", "2", and "3" represent the three different states that the chip reaches in sequence during the pumping process. In practical applications, it can not only improve the throughput of microfluidic analysis, but also realize repeated analysis of the same fluid.

[0075] It should be noted that, in this embodiment, the number of pressing pumps included in the microfluidic chip is only an exemplary description and should not be understood as the only limitation of the present invention. In practical applications, the number of pressing pumps in parallel can be adjusted according to specific analysis requirements.

[0076] Embodiment 3:

[0077] A microfluidic chip, such as Figure 8 As shown in (a), it includes: 5 pressing pumps, the pressing pumps are the pressing pumps provided in the above embodiment 1;

[0078] Among them, the fluid inlet of each pressing pump is independent of each other, and the fluid outlets of the five pressing pumps are connected to one point. Accordingly, the microfluidic chip has five fluid inlets and one fluid outlet; the pressing airbags of the five pressing pumps are the same pressing airbag.

[0079] The microfluidic chip provided in this embodiment is composed of 5 press pumps, the fluid layers in the 5 press pumps are connected in parallel, and the flow channel outlets are connected to one point. At the same time, the 5 press pumps in the microfluidic chip are controlled by the same press airbag, so that 5 fluids can be pumped to the same point at the same time through one operation. Figure 8 As shown in (b), it is convenient for subsequent mixing, reaction and other operations. Figure 8 In (b), “1”, “2” and “3” represent the three different states that the chip reaches in sequence during the pumping process.

[0080] It should be noted that, in this embodiment, the number of pressing pumps included in the microfluidic chip is only an exemplary description and should not be understood as the only limitation of the present invention. In practical applications, the number of pressing pumps in parallel can be adjusted according to specific analysis requirements.

[0081] Embodiment 4:

[0082] A microfluidic chip, such as Fig. 9 As shown in (a), it includes: the pressing pump and the liquid separation module provided in the above embodiment 1;

[0083] The liquid separation module includes an inlet flow channel, a liquid separation chamber and 6 outlet flow channels; one end of the inlet flow channel is connected to the liquid separation chamber, and the other end is connected to the fluid outlet of the pressing pump as the inlet of the liquid separation module; one end of the outlet flow channel is connected to the liquid separation chamber, and the other end serves as an outlet of the liquid separation module.

[0084] In this embodiment, a liquid separation chamber is connected to the outlet of the pressing pump, and the liquid separation chamber divides the fluid pumped by the pressing pump into 6 paths, which flow out through different outlets. In practical applications, different test papers can be directly set at the 6 outlets, or each outlet can be connected to a different analysis device, such as Fig. 9 As shown in (b) in FIG. 1 , different tests are performed on the same fluid. Fig. 9 In (b), “1”, “2” and “3” represent three different states that the chip reaches in sequence during the pumping process.

[0085] It should be noted that, in this embodiment, the number of outlet flow channels is only an exemplary description and should not be understood as the only limitation of the present invention. In practical applications, the number of outlet flow channels can be adjusted according to specific analysis requirements.

[0086] Embodiment 5:

[0087] A microfluidic chip, such as Fig.10 As shown in (a), it includes: 4 liquid storage chambers and 4 pressing pumps, and the pressing pumps are the pressing pumps provided in the above-mentioned embodiment 1;

[0088] The fluid layers of the four pressing pumps are connected in sequence, and the fluid outlet of the last pressing pump is connected to the fluid inlet of the first pressing pump. A liquid storage chamber is set at the connection of the fluid layers of adjacent pressing pumps; the pressing airbags of adjacent pressing pumps are different.

[0089] The microfluidic chip provided in this embodiment forms a flow channel structure that can control the circulation of liquid in four chambers by connecting the fluid layers of four pressure pumps end to end in sequence. Optionally, in this embodiment, four pressure pumps are connected in sequence to form a square circulation channel structure, and the four liquid storage chambers are arranged at the four corners of the square, and the pressure pumps are arranged on the four sides, and the two pressure pumps on the upper and lower sides are controlled by a common pressure airbag A as a group, and the two pressure pumps on the left and right sides are controlled by a common pressure airbag B as a group.

[0090] In practical applications, by placing different reaction test papers or reactants in the liquid storage chamber, the corresponding reactions can be controlled in sequence when the fluid flows along the circulation channel structure. In practical applications, any liquid storage chamber port can be selected as the inlet of the entire microfluidic chip. After the fluid circulates for one cycle, it can also flow out through the inlet, which is convenient for reagent recovery. Fig.10 As shown in (b), "1", "2" and "3" represent three different states that the chip reaches in sequence during the pumping process.

[0091] In order to control the movement of the fluid in the circulation channel structure, adjacent pressing pumps are controlled by different pressing airbags. In order to reduce the number of pressing airbags, non-adjacent pressing pumps can share the same pressing airbag. In practical applications, each pressing pump can also be controlled by a separate pressing airbag.

[0092] It should be noted that, in this embodiment, the number of the pressing pumps and the liquid storage chambers is only an exemplary description and should not be understood as the only limitation of the present invention. In practical applications, the number of the pressing pumps and the liquid storage chambers can be adjusted according to specific analysis requirements.

[0093] Embodiment 6:

[0094] A microfluidic chip, such as Fig.11 As shown in (a), it includes: a reaction chamber and 5 pressing pumps; the pressing pump is the pressing pump provided in the above embodiment 1;

[0095] The fluid inlet and the pressing airbag of each pressing pump are independent of each other, and the fluid outlets of the 5 pressing pumps are all connected to the reaction chamber.

[0096] The microfluidic chip provided in this embodiment includes 5 pressing pumps, the fluid inlet and pressing airbag of each pressing pump are independent of each other, and the fluid outlet of each pressing pump is connected to the same reaction chamber, so that the order in which each pressing pump pumps pumps fluids can be independently controlled, thereby controlling the order in which each fluid is released into the reaction chamber, and realizing complex analytical reactions, such as Fig.11 As shown in (b), "1", "2" and "3" represent three different states that the chip reaches in sequence during the pumping process.

[0097] It should be noted that, in this embodiment, the number of outlet flow channels is only an exemplary description and should not be understood as the only limitation of the present invention. In practical applications, the number of outlet flow channels can be adjusted according to specific analysis requirements.

[0098] Embodiment 7:

[0099] A microfluidic chip, such as Fig.12 As shown, it includes: a concentration gradient generating module and two pressing pumps; the pressing pump is the pressing pump provided in the above embodiment 1;

[0100] A Christmas tree structure fluid microchannel is provided in the concentration gradient generation module; Fig.12As shown in (c) and (d) in the figure, the fluid microchannels of the Christmas tree structure include multiple layers of longitudinal microchannels and multiple layers of transverse microchannels; the number of longitudinal microchannels in the first layer is 2, and the number of longitudinal microchannels in each subsequent layer is 1 more than the number of longitudinal microchannels in the previous layer; the transverse microchannel is arranged at the junction of two adjacent layers of longitudinal microchannels and is connected to the adjacent longitudinal microchannels; the fluid inlet of each pressing pump is independent of each other, and the fluid outlet of the two pressing pumps is respectively connected to the two longitudinal microchannels located in the first layer in the concentration gradient generation module, and the pressing airbags of the two pressing pumps are the same pressing airbag.

[0101] In practical applications, the two pressing pumps are used to pump the original liquid to be diluted and the diluent used to dilute the original liquid respectively. After the pressing airbag is pressed, the original liquid and the diluent will be pumped forward along the fluid microchannel of the Christmas tree structure; based on the microfluidic channel structure of the Christmas tree structure, after the fluid flows from the previous level of longitudinal flow channel to the transverse flow channel, it will be diverted to both sides along the transverse flow channel and then converge to flow into the next level of longitudinal flow channel. Finally, the concentration of the liquid output from each outlet will increase from the diluent to the original liquid, thereby forming a concentration gradient, such as Fig.12 As shown in (c) and (d) in FIG. 1 , the concentration of the output liquid of each outlet is fitted, and it can be found that the concentration of the output liquid of each outlet has a good linear relationship, as shown in FIG. Fig.12 As shown in (e) in the figure, it is illustrated that the microfluidic analysis chip provided in this embodiment can generate a standard concentration gradient through the combination of the pressure pump and the microchannel.

[0102] As an optional implementation, this embodiment adopts a layered design solution for the chip, such as Fig.12 As shown in (a), the first layer of PMMA is to expand the liquid storage capacity of the inlet chamber, the second layer is a silicone membrane as a button, and the third and fourth layers of PMMA form a fluid channel, including two sets of push pumps and a Christmas tree gradient generation structure. Each set of push pumps includes a push check valve, a brake chamber and two passive check valves. The fifth layer is a double-sided adhesive that limits the deformation of the silicone membrane, the sixth layer is a thin silicone membrane, and the seventh layer is a pneumatic layer. The button connects the push check valve and the brake chamber through the airway. The overall structural dimensions of the chip are shown in Figure 1. Fig.12 As shown in (b) in .

[0103] It should be noted that in practical applications, the microfluidic chip may adopt other layered design schemes, and the chip size may also be adjusted accordingly according to actual needs.

[0104] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A compression pump, characterized in that: include: A pressing airbag, a brake chamber and two one-way valves; the two one-way valves are respectively a first one-way valve and a second one-way valve; The one-way valve comprises: a first thermoplastic material film, a second thermoplastic material film, a first elastic film, and a first double-sided adhesive film which are attached in sequence from bottom to top, a third thermoplastic material film fixed to the top of the first double-sided adhesive film by a first support column, and a cylindrical microvalve whose upper bottom surface is attached to the lower surface of the third thermoplastic material film; the cylindrical microvalve is made of thermoplastic material, and the height of the first support column is not less than the height of the cylindrical microvalve; the circular area with a radius of r1 located directly below the cylindrical microvalve in the first double-sided adhesive film and the second thermoplastic material film is cut; the structure above the first elastic film forms the fluid layer of the one-way valve, and the structure below the first elastic film forms the gas layer of the one-way valve; The brake chamber comprises: a fourth thermoplastic film, a fifth thermoplastic film, a second elastic film, a second double-sided adhesive film, which are attached in sequence from bottom to top, a sixth thermoplastic film fixed on the second double-sided adhesive film by a second support column, and a seventh thermoplastic film attached to the upper surface of the sixth thermoplastic film; circular areas with a radius of r2 at the same position in the fifth thermoplastic film, the second double-sided adhesive film and the sixth thermoplastic film are all cut; the structure above the second elastic film forms a fluid layer of the brake chamber, and the structure below the second elastic film forms a gas layer of the brake chamber; The fluid layer of the first one-way valve, the fluid layer of the brake chamber and the fluid layer of the second one-way valve are connected in sequence, the fluid layer inlet of the first one-way valve serves as the fluid inlet of the pressing pump, and the fluid layer outlet of the second one-way valve serves as the fluid outlet of the pressing pump; the cut circular areas in the gas layers of the first one-way valve and the brake chamber are connected to the pressing airbag through the gas path microchannel; Among them, r0≤r1≤r2, r0 is the bottom radius of the cylindrical valve.

2. The pressing pump according to claim 1, characterized in that: The first thermoplastic film, the second thermoplastic film, the third thermoplastic film, the fourth thermoplastic film, the fifth thermoplastic film, the sixth thermoplastic film, the seventh thermoplastic film and the cylindrical microvalve are all made of PMMA.

3. The pressing pump according to claim 1 or 2, characterized in that: The first elastic film and the second elastic film are both made of silicone.

4. A microfluidic chip, characterized in that: include: N1 pressing pumps; the pressing pump is the pressing pump according to any one of claims 1 to 3; The fluid inlet and fluid outlet of each pressing pump are independent of each other, and the pressing airbags of the N1 pressing pumps are the same pressing airbag; N1≥2.

5. A microfluidic chip, characterized in that: include: N2 pressing pumps, wherein the pressing pump is the pressing pump according to any one of claims 1 to 3; Among them, the fluid inlets of each pressing pump are independent of each other, the fluid outlets of N2 pressing pumps are connected to one point, and the pressing airbags of the N2 pressing pumps are the same pressing airbag; N2≥2.

6. A microfluidic chip, characterized in that: include: The pressing pump and the liquid dispensing module according to any one of claims 1 to 3; The liquid separation module comprises an inlet flow channel, a liquid separation chamber and N3 outlet flow channels; one end of the inlet flow channel is connected to the liquid separation chamber, and the other end is connected to the fluid outlet of the pressing pump as the inlet of the liquid separation module; one end of the outlet flow channel is connected to the liquid separation chamber, and the other end is an outlet of the liquid separation module; Among them, N3≥2.

7. A microfluidic chip, characterized in that: include: N4 liquid storage chambers and N4 pressing pumps; the pressing pump is the pressing pump according to any one of claims 1 to 3; The fluid layers of the N4 pressing pumps are connected in sequence, and the fluid outlet of the last pressing pump is connected to the fluid inlet of the first pressing pump. A liquid storage chamber is provided at the connection of the fluid layers of adjacent pressing pumps; the pressing airbags of adjacent pressing pumps are different; Among them, N4≥3.

8. A microfluidic chip, characterized in that: include: A reaction chamber and N5 press pumps; the press pump is the press pump according to any one of claims 1 to 3; The fluid inlet and the pressing airbag of each pressing pump are independent of each other, and the fluid outlets of the N5 pressing pumps are all connected to the reaction chamber; Among them, N3≥2.

9. A microfluidic chip, characterized in that: include: A concentration gradient generating module and two pressing pumps; the pressing pumps are the pressing pumps according to any one of claims 1 to 3; The concentration gradient generating module is provided with a fluid microchannel of a Christmas tree structure; the fluid microchannel of the Christmas tree structure includes multiple layers of longitudinal microchannels and multiple layers of transverse microchannels; the number of longitudinal microchannels in the first layer is 2, and the number of longitudinal microchannels in each subsequent layer is 1 more than the number of longitudinal microchannels in the previous layer; the transverse microchannel is provided at the junction of two adjacent layers of longitudinal microchannels, and is connected to the adjacent longitudinal microchannels; The fluid inlet of each pressing pump is independent of each other, and the fluid outlets of the two pressing pumps are respectively connected to the two longitudinal microchannels located in the first layer of the concentration gradient generating module, and the pressing airbags of the two pressing pumps are the same pressing airbag.

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