High-flow-rate and large-preparation-amount microfluidic equipment

Abstract

The utility model relates to microfluidic equipment with high flow rate and large preparation capacity, which comprises a liquid pushing mechanism, a microfluidic liquid phase mixing chip mechanism, a sample collecting mechanism and a liquid receiving mechanism, a microfluidic mixing channel is arranged in the microfluidic liquid phase mixing chip mechanism, the microfluidic mixing channel is Y-shaped, and the sample collecting mechanism is arranged in the microfluidic liquid phase mixing chip mechanism. One end of the micro-flow mixing channel is provided with two liquid inlets, the other end of the micro-flow mixing channel is provided with a liquid outlet, the liquid pushing mechanism is connected with the two liquid inlets, the liquid receiving mechanism is connected with the liquid outlet, and the sample collecting mechanism is in transmission connection with the liquid receiving mechanism. The device is simple in structure, good in large-screen touch interaction experience, convenient to operate, high in automation degree, stable in preparation, high in accuracy and capable of automatically and accurately controlling the liquid inlet amount and the liquid inlet speed of stock solutions entering the micro-flow liquid phase mixing chip mechanism in two channels, so that the mixing ratio of two groups of liquid phases is accurately controlled, and the production efficiency is improved. Two-phase liquids with different dosage forms and different mixing speeds can be accurately and quickly mixed, and the total flow velocity is up to 600mL / min.

Description

Technical Field

[0001] The utility model relates to the technical field of microfluidic control, and particularly relates to a high-flow-rate and large-preparation-capacity microfluidic device. Background Technique

[0002] Microfluidics is a science and technology that precisely controls and manipulates micro-scale fluids and mainly features the manipulation of fluids in a micro-nano scale space. Microfluidic technology has the ability to miniaturize basic functions such as sample preparation, reaction, separation, and detection in biological, chemical, and other laboratories onto a chip of a few square centimeters. Its basic feature and greatest advantage are the flexible combination and large-scale integration of various unit technologies on an overall controllable micro-platform, and it is an interdisciplinary subject involving fields such as engineering, physics, chemistry, microfabrication, and bioengineering.

[0003] Lipid nanoparticles are an advanced gene delivery vector. With their successful application in mRNA COVID-19 vaccines in recent years, research on their use as delivery vectors in gene therapy drugs has received extensive attention. The encapsulation of nucleic acid drugs by lipid nanoparticles is completed during the rapid mixing of lipid solutions and nucleic acid solutions. The positive and negative charge interaction forces between lipids and nucleic acids and the self-assembly properties of amphiphilic lipids enable nucleic acids to be encapsulated in lipid nanoparticles. The formation process and principle determine that microfluidic mixing technology is suitable for the application and promotion of lipid nanoparticle preparation. Moreover, this preparation method is simple, rapid, has mild conditions, and is easy to scale up production. Microfluidic technology uses two channels to rapidly mix an ethanol solution of lipids and a weakly acidic solution of nucleic acids, and controlling the fluid velocity and ratio of the two channels can control the composition and particle size of lipid nanoparticles.

[0004] However, common microfluidic devices currently on the market have problems such as high usage costs and limited application scenarios. Taking the NanoAssemblr product as an example, the maximum single mixing capacity of this microfluidic device is 12 mL, which cannot meet the usage requirements for preparing large-volume samples; the maximum mixing speed is 16 mL / min, which cannot meet the usage scenario requirements for high-speed liquid mixing; it can only be compatible with 10 mL and 1 mL syringes; moreover, the microfluidic chip can only be used once, resulting in relatively high usage costs. Content of the Utility Model

[0005] To solve the technical problems existing in the prior art, the utility model provides a high-flow-rate and large-preparation-capacity microfluidic device, which has a simple structure, a good large-screen touch interaction experience, is easy to operate, can automatically and precisely control the inlet velocity of raw liquid and the mixing ratio of two phases, has stable preparation, high flow rate, and a large sample preparation volume.

[0006] To achieve the above purpose, the technical solution of the utility model is as follows:

[0007] A high-flow-rate and large-preparation-capacity microfluidic device, comprising a liquid-pushing mechanism, a microfluidic liquid-phase mixing chip mechanism, a sample-collecting mechanism, and a liquid-receiving mechanism. Inside the microfluidic liquid-phase mixing chip mechanism, there is a microfluidic mixing channel, which is Y-shaped. One end of the microfluidic mixing channel is provided with two liquid inlets, and the other end of the microfluidic mixing channel is provided with one liquid outlet. The liquid-pushing mechanism is connected to the two liquid inlets, the liquid-receiving mechanism is connected to the liquid outlet, and the sample-collecting mechanism is in transmission connection with the liquid-receiving mechanism.

[0008] As a preferred technical solution, the liquid-pushing mechanism includes two pushing components and an initial position detection sensor, and the initial position detection sensor is installed between the two pushing components.

[0009] As a preferred technical solution, the pushing component includes a pushing mounting seat, a slide screw, and a liquid-pushing pusher. The slide screw is installed on the pushing mounting seat, and the liquid-pushing pusher is installed on the slide screw.

[0010] As a preferred technical solution, the liquid-pushing pushers of the two pushing components are respectively connected to the piston handle of a syringe, and the injection holes of the two syringes are respectively connected to the two liquid inlets.

[0011] As a preferred technical solution, the liquid-pushing pusher includes a pusher body, a bearing, and a pusher contact plate. The pusher body is installed on the slide screw, and the front end of the pusher body is hinged to the pusher contact plate through the bearing.

[0012] As a preferred technical solution, a pusher support structure is fixedly installed at the rear end of the pusher body, a pushing pressure sensor is installed on the pusher support structure, and the front end face of the pusher contact plate is in elastic contact with the pushing pressure sensor.

[0013] As a preferred technical solution, the sample-collecting mechanism includes a driving gear, a servo motor, and a support base. The servo motor is installed at the center of the support base, and the servo motor is in transmission connection with the driving gear above. A rack is provided on one side of the liquid-receiving mechanism, and the driving gear meshes with the rack.

[0014] As a preferred technical solution, the liquid-receiving mechanism includes a test tube clamp structure arranged below the liquid outlet. The rack is fixed on the side of the test tube clamp structure close to the servo motor. A slide rail is provided on the side of the support base close to the liquid-receiving mechanism. A sliding bar is provided on the side of the test tube clamp structure close to the servo motor below, and the sliding bar is slidably connected to the slide rail. A circular slot is provided on the test tube clamp structure.

[0015] As a preferred technical solution, the microfluidic device further includes a device main control unit, and the device main control unit includes a touch screen interaction control mechanism and a housing. The touch screen interaction control mechanism is in signal connection with the liquid-pushing mechanism and the sample-collecting mechanism.

[0016] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0017] (1) A high-flow-rate and large-preparation-capacity microfluidic device of the present utility model has a simple structure, high degree of automation, good interaction solutions, and high preparation accuracy. The present utility model precisely controls the liquid inlet volume and liquid inlet speed of the stock solutions in two channels entering the micro-mixing device through automation, so as to precisely control the mixing ratio of two liquid phases.

[0018] (2) In a high-flow-rate and large-preparation-capacity microfluidic device of the present utility model, the touch screen, micro-control chip, and each sensor component of the touch-screen interaction control mechanism form a complete system. The UI interface is intuitive, the operation is convenient, it can feedback the intuitive working state and process, and provides good interaction.

[0019] (3) In a high-flow-rate and large-preparation-capacity microfluidic device of the present utility model, the liquid pushing mechanism combines multiple sensors to collect real-time motion data and real-time pressure data in the channel during the preparation process, improves the liquid feeding accuracy, and automatically processes the motion during the liquid phase preparation process.

[0020] (4) In a high-flow-rate and large-preparation-capacity microfluidic device of the present utility model, the micro-mixing device uses a tempered microfluidic chip. A micro-channel is provided inside the chip, and the internal is a Y-shaped micro-fluid channel. At the junction of the two liquid inlet channels, a Z-shaped micro-channel structure is designed, which helps the two-phase liquids to be fully combined.

[0021] (5) In a high-flow-rate and large-preparation-capacity microfluidic device of the present utility model, the liquid receiving device is provided with a linear gear structure, on which three groups of adjacent test tube clamp structures are provided. The test tube clamp structure is a circular structure, which is convenient for placing test tubes or centrifuge tubes for collecting liquids. Its arc-shaped structure tightly fixes the collecting test tube, and the opening design is convenient for removing the mixed sample; the linear mechanism is arranged below the micro-fluid mixing mechanism, which not only saves structural space, but also realizes the separate receiving of waste liquid and target liquid.

[0022] (6) A high-flow-rate and large-preparation-capacity microfluidic device of the present utility model has a mixing liquid phase flow rate range of 0 - 600 mL / min, a wider application range, and can be used in various business scenarios such as early process exploration and later process scale-up. Description of the Drawings

[0023] Figure 1 is a schematic structural diagram of a high-flow-rate and large-preparation-capacity microfluidic device of the present utility model;

[0024] Figure 2 is a schematic structural diagram of the back of the housing of the device main control unit in a high-flow-rate and large-preparation-capacity microfluidic device of the present utility model;

[0025] Figure 3 is a schematic structural diagram of the liquid pushing mechanism in a high-flow-rate and large-preparation-capacity microfluidic device of the present utility model;

[0026] Figure 4 It is a schematic diagram of the installation structure of the push liquid pusher in a high-flow-rate and large-preparation-capacity microfluidic device of the present utility model;

[0027] Figure 5 It is a schematic diagram of the structure of the push liquid pusher in a high-flow-rate and large-preparation-capacity microfluidic device of the present utility model;

[0028] Figure 6 It is a schematic diagram of the external structure of the microfluidic liquid mixing chip mechanism in a high-flow-rate and large-preparation-capacity microfluidic device of the present utility model;

[0029] Figure 7 It is a schematic diagram of the structure of the chip in a high-flow-rate and large-preparation-capacity microfluidic device of the present utility model;

[0030] Figure 8 It is a schematic diagram of the structure of the liquid receiving mechanism in a high-flow-rate and large-preparation-capacity microfluidic device of the present utility model;

[0031] Figure 9 It is a schematic diagram of the test tube clamp structure in a high-flow-rate and large-preparation-capacity microfluidic device of the present utility model

[0032] Figure 10 It is a schematic diagram of the experimental results of pDNA / MC3 LNP in a high-flow-rate and large-preparation-capacity microfluidic device of the present utility model in mice.

[0033] In the figure: 1. High-flow-rate and large-preparation-capacity microfluidic device; 2. Housing; 21. Touch screen; 22. Device switch; 23. Line interface; 24. Device power supply; 25. Device external cable; 26. Main control unit heat dissipation; 3. Push liquid mechanism; 31. Push installation seat; 32. Slide table screw; 33. Push liquid pusher; 4. Chip; 41. Microfluidic mixing channel; 51. Pusher contact plate; 52. Initial position detection sensor; 53. Push pressure sensor; 6. Syringe; 7. Microfluidic liquid mixing chip mechanism; 71. Liquid inlet; 72. Liquid outlet; 81. Cover plate; 82. Driving gear; 83. Servo; 84. Support bottom; 85. Guide rail; 9. Liquid receiving mechanism; 91. Liquid receiving centrifuge tube; 92. Sample collection centrifuge tube; 93. Test tube clamp structure; 94. Rack. Specific embodiments

[0034] The technical solutions of the present utility model will be further described below in conjunction with specific embodiments:

[0035] In this embodiment, as Figure 1 shown, a high-flow-rate and large-preparation-capacity microfluidic device 1 includes a device main control unit and a mechanical working body, as Figure 2As shown, the device main control unit includes a housing 2, a touch screen 21 and a device switch 22 located on the front of the housing 2, as well as a circuit interface, a device power supply, a device external cable and main control unit heat dissipation located on the back of the housing 2. The touch screen interaction control mechanism forms a 75-degree angle with the housing 2. The mechanical working main body includes a liquid pushing mechanism 3, a microfluidic liquid phase mixing chip mechanism 7, a sample collection mechanism and a liquid receiving mechanism 9. As Figure 7 shown, inside the chip 4 in the microfluidic liquid phase mixing chip mechanism 7, there is a microfluidic mixing channel 41. The microfluidic mixing channel 41 is Y-shaped. One end of the microfluidic mixing channel 41 is provided with two liquid inlets 71. As Figure 6 shown, the two liquid inlets 71 are communicated with the two outer sides of the microfluidic liquid phase mixing chip mechanism 7. The other end of the microfluidic mixing channel 41 is provided with an outlet 72. The outlet 72 is communicated with the outside of the microfluidic liquid phase mixing chip mechanism 7. The liquid pushing mechanism 3 is connected to the two liquid inlets 71. The liquid receiving mechanism 9 is connected to the outlet 72. The sample collection mechanism is drivingly connected to the liquid receiving mechanism 9. The touch screen interaction control mechanism controls the operation of the liquid pushing mechanism 3 and the sample collection mechanism through signals. In this embodiment, in order to enable the chip 4 to withstand the pressure brought by a large flow rate, the chip 4 is tempered.

[0036] As Figure 3 shown, the liquid pushing mechanism 3 includes two pushing components and an initial position detection sensor 52. Each pushing component includes a pushing mounting base 31, a slide screw 32 and a liquid pushing pusher 33. The initial position detection sensor 52 is installed between the two pushing mounting bases 31. The slide screw 32 is installed on the pushing mounting base 31. The slide screw 32 includes a stepping motor, a moving block, a lead screw and a constraint rod. The moving block is provided with a threaded hole and a through hole. The threaded hole is provided with a thread matching the lead screw. The lead screw passes through the threaded hole. The constraint rod passes through the through hole. As Figure 4 shown, the liquid pushing pusher 33 is fixedly connected to the moving block and is arranged on the slide screw 32. The stepping motor drives the lead screw to rotate. While the constraint rod restricts the moving direction of the moving block, the moving block moves along the lead screw, driving the liquid pushing pusher 33 to move. The two liquid pushing pushers 33 are respectively connected to the piston handles of a syringe 6. The injection holes of the two syringes 6 are respectively connected to the two liquid inlets 71. When the liquid pushing pusher 33 moves forward, the syringe pushes the raw material liquid into the two liquid inlets 71 of the microfluidic liquid phase mixing chip mechanism 7.

[0037] The utility model uses a slide screw 32 in combination with a stepper motor, and a touch screen interactive control mechanism developed using the platform of the STM32F7 series ultra-high performance MCU to achieve accurate real-time stepper motor drive, and multiple sensor drives work closely together to achieve automated precise positioning and liquid mixing. The stepper motor drives the MCU's advanced timer to accurately output a specified high-frequency PWM waveform to achieve precise control of the push speed and distance. The MCU can output a PWM frequency range of 20HZ to 100KHZ. The main control unit of the device can achieve a maximum movement accuracy of 0.0006mm by further subdividing the output PWM, which is of great significance for the precise mixing of two-phase liquids.

[0038] like Figure 5 As shown, the liquid pusher 33 includes a pusher body, a bearing and a pusher contact plate 51. The pusher body is mounted on the slide screw 32. The front end of the pusher body is hinged to the pusher contact plate 51 through the bearing. The rear end of the pusher body is fixedly mounted with a pusher support structure, and a push pressure sensor 53 is mounted on the pusher support structure. The front end surface of the pusher contact plate 51 is in elastic contact with the push pressure sensor 53. The push pressure sensor 53 carries the initial position detection sensor 52 and the push contact plate. The initial position detection sensor 52 and the push contact plate contact the syringe 6 to push the motion transmission torque to the push pressure sensor 53, thereby obtaining real-time pressure data of the whole preparation process.

[0039] like Figure 8 As shown, the sample collecting mechanism includes a cover plate 81, a driving gear 82, a steering gear 83 and a supporting base 84. The steering gear 83 is installed on the supporting base 84, and the steering gear 83 is transmission-connected to the driving gear 82. The cover plate 81 is arranged above the supporting base 84 and the driving gear 82.

[0040] like Figure 8 and Figure 9 As shown, the liquid receiving mechanism 9 includes a test tube clamp structure 93 disposed below the liquid outlet 72 to receive the microfluid mixture from the liquid outlet 72. A rack 94 is fixed to the side of the test tube clamp structure 93 close to the steering gear 83, and the driving gear 82 is meshed with the rack 94. A slide rail is provided on the side of the support base 84 close to the liquid receiving mechanism 9, and the direction of the slide rail is consistent with the moving direction of the rack 94. A sliding bar is provided on the side of the test tube clamp structure 93 close to the steering gear 83, and the sliding bar is slidably connected to the slide rail. In this embodiment, three circular grooves are provided on the test tube clamp structure 93.

[0041] The working process of the high-flow-rate and large-preparation-capacity microfluidic device 1 of the present utility model is as follows: After connecting two syringes 6 to two liquid inlet ports 71 of the microfluidic liquid mixing chip mechanism 7 respectively; placing the liquid receiving centrifuge tube 91 and the sample collection centrifuge tube 92 in two circular slots corresponding to the models on the test tube clamp structure 93 respectively, and moving along with the sample collection mechanism; then, setting the volumes of the two-phase liquids to be 30 mL and 90 mL respectively, the total flow rate to be 160 mL / min, and the waste liquid collection to be 5 mL in the device main control unit. Through initialization settings, the two syringes 6 are driven to work by two sets of slide screw rods 32, and the initial positions of the pistons of the syringes 6 are accurately positioned under the control of two sets of initial position detection sensors 52. By starting the program in the device main control unit, the syringes 6 are controlled to push the two-phase liquids according to the set ratio and flow rate. At the same time, after the liquid receiving centrifuge tube 91 has collected the set volume of waste liquid, the servo motor 83 in the sample collection mechanism is controlled to drive the driving gear 82 to rotate, driving the rack 94 and the liquid receiving mechanism 9 to translate along the slide rail direction, so that the sample collection centrifuge tube 92 moves to the liquid receiving position for sample collection. After the set program is completed and the sample preparation is completed, the liquid pushing movement will stop, and at this time, the sample collection centrifuge tube 92 can be removed. During the pushing process of the two-phase liquids, if one of the phase liquids is lower than the set parameters, the syringe 6 will stop moving in advance.

[0042] The working process of the core components of the device is as follows: Set the amount and speed of the liquid pushed by the two liquid inlets 71 on the touch screen 21 interactive interface respectively. The system obtains the set values, calculates them into the corresponding number of PWMs and PWM frequencies, and then sends the data to the driver. Set the data of the specific timer-related registers in the MCU, and then start the timer to work. The timer work does not occupy the main process of the MCU, avoiding the timing impact on the accuracy of driving the stepper motor caused by the operation of the main thread. Therefore, the two stepper motors start to start according to the setting, driving the slide screw 32 to push the corresponding syringes 6 to inject the raw material liquid. The raw material liquid entering the two liquid inlets 71 is mixed through the microfluidic mixing channel 41. At the beginning of the design of the present utility model, the single mixing capacity, speed and the use scenarios of compatible with various models of syringes 6 were considered. In order to meet the situation of large-capacity mixing, a lead screw slide table with a larger effective stroke is designed, and the effective load is also correspondingly increased. The device system is also optimized and adapted for large-capacity mixing, so as to ensure that the device can effectively complete the demand of large-capacity liquid-phase mixing. The present utility model is compatible with various models of syringes. The present utility model can not only be used for the screening of low-flow nano-drug lipid formulations in the low-flow rate range of 1-60 mL / min in the early stage, but also break through the problem that traditional microfluidic devices cannot perform process amplification, and the highest flow rate can support up to 600 mL / min. The device of the present utility model has a simple structure, high automation, convenient operation, and high preparation precision. The microfluidic mixing device is used to prepare the microfluidic mixture, and the liquid inlet amount and liquid inlet speed of the raw material liquid entering the microfluidic mixing device are accurately controlled automatically to accurately control the ratio between the raw material liquids.

[0043] This embodiment provides a high-flow rate and large-preparation amount microfluidic device 1 for preparing a classical LNP formulation: Using the classical LNP formulation of cationic Dlin-MC3-DMA, a lipid ethanol solution of 30 ml was obtained by dissolving four components including cation, cholesterol, co-phospholipid DOPC, and PEG2000-DMG in ethanol according to a molar ratio of 50:38:10:2; Dilute the pDNA plasmid expressing firefly luciferase in an acetate solution with a pH of 4, and obtain pDNA / MC3 LNP according to the parameters set in Table 1 below. The particle size, distribution and encapsulation efficiency of the obtained LNP are shown in Table 1 below.

[0044] Table 1 Preparation of classical LNP formulation

[0045]

[0046] The above PDI represents the particle dispersity index. The data results confirm that the gene drug encapsulating DNA obtained by the present utility model has a small particle size, good dispersity and high encapsulation efficiency.

[0047] The pDNA / MC3 LNP of a high-flow-rate and large-preparation-capacity microfluidic device 1 of the present utility model shows good pDNA delivery effect in in-vivo experiments on mice. The expression level of firefly luciferase in mice reaches ~3×107 p / s, and the results are as Figure 10 shown.

[0048] This embodiment is only a further explanation of the present invention, rather than a limitation thereof. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed, but as long as it is within the scope of the claims of the present invention, it is protected by the patent law.

Claims

1. A high-flow-rate and large-preparation-capacity microfluidic device, characterized in that, It includes a liquid pushing mechanism, a microfluidic liquid mixing chip mechanism, a sample collection mechanism and a liquid receiving mechanism. Inside the microfluidic liquid mixing chip mechanism, there is a microfluidic mixing channel. The microfluidic mixing channel is in a Y shape. One end of the microfluidic mixing channel is provided with two liquid inlets, and the other end of the microfluidic mixing channel is provided with one liquid outlet. The liquid pushing mechanism is connected to the two liquid inlets, the liquid receiving mechanism is connected to the liquid outlet, and the sample collection mechanism is in transmission connection with the liquid receiving mechanism.

2. The high-flow-rate and large-preparation-capacity microfluidic device according to claim 1, characterized in that, The liquid pushing mechanism includes two pushing components and an initial position detection sensor, and the initial position detection sensor is installed between the two pushing components.

3. The high-flow-rate and large-preparation-capacity microfluidic device according to claim 2, characterized in that, The pushing component includes a pushing mounting seat, a slide screw and a liquid pushing pusher. The slide screw is installed on the pushing mounting seat, and the liquid pushing pusher is installed on the slide screw.

4. A high-flow-rate and large-preparation-capacity microfluidic device according to claim 3, characterized in that The liquid pushing pushers of the two pushing components are respectively connected to the piston handle of a syringe, and the injection holes of the two syringes are respectively connected to the two liquid inlets.

5. A high-flow-rate and large-preparation-capacity microfluidic device according to claim 3, wherein, The liquid pushing pusher includes a pusher body, a bearing and a pusher contact plate. The pusher body is installed on the slide screw, and the front end of the pusher body is hinged to the pusher contact plate through the bearing.

6. The high-flow-rate and large-preparation-capacity microfluidic device according to claim 5, characterized in that A pusher support structure is fixedly installed at the rear end of the pusher body, and a pushing pressure sensor is installed on the pusher support structure. The front end face of the pusher contact plate is elastically in contact with the pushing pressure sensor.

7. A high-flow-rate and large-preparation-capacity microfluidic device according to claim 1, characterized in that, The sample collection mechanism includes a driving gear, a servo motor and a support base. The servo motor is installed at the center of the support base, and the servo motor is in transmission connection with the driving gear above. A rack is provided on one side of the liquid receiving mechanism, and the driving gear meshes with the rack.

8. A high-flow-rate and large-preparation-capacity microfluidic device according to claim 7, characterized in that The liquid receiving mechanism includes a test tube clamp structure arranged below the liquid outlet. The rack is fixed on one side of the test tube clamp structure close to the servo motor. A slide rail is provided on one side of the support base close to the liquid receiving mechanism. A sliding bar is provided on one side of the test tube clamp structure below close to the servo motor, and the sliding bar is slidably connected to the slide rail. A circular slot is provided on the test tube clamp structure.

9. A high-flow-rate and large-preparation-capacity microfluidic device according to claim 1, characterized in that, The microfluidic device further includes a device main control unit. The device main control unit includes a touch screen interaction control mechanism and a housing. The touch screen interaction control mechanism is in signal connection with the liquid pushing mechanism and the sample collection mechanism.

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