A multichannel microfluidic emulsion membrane for large-scale manufacturing of monodisperse emulsion droplets and its applications

Abstract

This invention belongs to the field of membrane emulsification technology, specifically a multi-channel microfluidic emulsion membrane for large-scale manufacturing of monodisperse emulsion droplets and its applications. The emulsion membrane includes at least one through-hole, the through-hole having a rectangular cross-section with a shorter side length of 0.005-1.5 mm and a side length ratio of 1:2-1:10 to the longer side. The emulsion membrane of this invention combines membrane emulsification technology with microfluidic droplet technology, enabling low-energy, high-throughput, and automated production of various small-particle-size, narrow-distribution microemulsions with unique manufacturing requirements through matrix arrangement and free shaping. Based on microfluidic droplet technology, the through-hole structure of this invention can achieve high-precision emulsification of emulsion levels comparable to traditional dilute solution emulsification without the aid of external forces.

Description

Technical Field

[0001] This invention belongs to the field of membrane emulsification technology, specifically a design of a multi-channel microfluidic emulsification membrane and its emulsification device based on microfluidic principles, and an application method for using the device to mass-produce monodisperse emulsion droplets with uniform size. Background Technology

[0002] Emulsion technology is widely used to prepare microdroplets encapsulating bioactive substances (such as bioactive macromolecular drugs or living cells). It has broad applications in chemical engineering, pharmaceuticals, and biochemistry. Highly homogeneous microdroplets can also serve as standard droplets in various high-precision biochemical and immunological experiments, such as tissue engineering, single-cell and single-molecule research. Common emulsion methods include membrane emulsification, spray emulsification, stirred emulsification, and the emerging microfluidic method. Among these, membrane emulsification technology is characterized by low energy consumption, mild conditions, and high throughput, and has been widely used in the preparation of various cosmetics, food, and drug carriers. Conventional membrane emulsification technology typically utilizes the flow of the dispersed phase through a membrane structure into the continuous phase. The dispersed phase grows at the membrane pores and, under the combined effects of surface tension, transmembrane pressure, continuous phase drag, and buoyancy, leaves the membrane surface to form droplets. Because conventional membrane emulsification technology relies on the force effect of the liquid phase to passively complete emulsification, the droplet size distribution is relatively wide. Therefore, droplets cannot be applied to the large-scale production of higher-precision emulsion products, such as drugs and cell carriers. Meanwhile, due to the limitations of the passive emulsification principle, it will be more difficult to achieve high-throughput production of small-particle-size emulsions when emulsifying high-viscosity dispersed phases, making it even more difficult to apply to the production of viscous microgels such as hydrogels.

[0003] In contrast, microfluidic methods can produce droplet emulsions with higher uniformity and are therefore widely used in various biochemical studies. This method typically utilizes two immiscible liquid phases to form a size-controllable monodisperse emulsion under highly controlled microscopic forces. Common microfluidic techniques for microdroplet production include passive emulsification using various structural controls and active emulsification using exogenous forces. However, these conventional microfluidic droplet technologies have the following problems: 1) They usually require highly precise microfluidic chips to complete droplet production, resulting in high chip equipment costs (CN 105641743A, CN104511320A); 2) The droplet production throughput of microfluidic droplet production technologies based on various microchannels is low (<1L / h), and it usually takes a long time to complete the production of a certain amount of uniform microemulsion droplets (CN112275336A, CN110038656A); 3) The emulsion formation process is highly dependent on the flow rate of each liquid phase, and the real-time control requirements of each liquid phase in the production process are high, making it difficult to achieve large-scale application in practice (CN107930542A, CN107511189A).

[0004] Therefore, achieving high-throughput preparation of high-viscosity dispersed phases remains a key issue for breakthroughs in the application of bioactive substance-loaded microparticles in clinical or other fields. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention provides a design for a multi-channel microfluidic emulsion membrane based on microfluidics and its application method for high-throughput mass production of monodisperse emulsion droplets.

[0006] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0007] The present invention provides a multi-channel microfluidic emulsion membrane for the manufacture of emulsion droplets, comprising at least one through hole, wherein the cross-section of the through hole is rectangular, the length of the short side of the cross-section is 0.005-1.5 mm, and the ratio of the length of the short side to the length of the long side is 1:2-1:10.

[0008] In the above technical solution, the through holes are arranged in a rectangular array, the spacing between the through holes in the first direction is 0.2-20 times the length of the long side, and the spacing between the through holes in the second direction is 0.4-20 times the length of the long side.

[0009] In the above technical solution, the thickness of the multi-channel microfluidic emulsion film is 0.01mm-10mm, and the depth of the through hole is more than 1 times the length of the long side.

[0010] In the above technical solution, the surface of the multi-channel microfluidic emulsion membrane is either strongly hydrophobic or strongly hydrophilic.

[0011] In the above technical solution, the multi-channel microfluidic emulsion membrane is further described as a tubular, sheet-like, or spherical membrane.

[0012] In the above technical solution, the multi-channel microfluidic emulsion membrane material is one or more of glass, silicon, metal, ceramic, organic polymer, or organic-inorganic composite material, and the through hole is processed by laser, drilling, etching, 3D printing or integral molding.

[0013] In the above technical solution, the through-hole array is located in the center of the multi-channel microfluidic emulsion membrane plane, and a blank area is left at the edge of the membrane without through-holes. The straight-line distance between the through-holes on the outer side of the through-hole array and the edge of the membrane is greater than twice the length of the long side.

[0014] A second aspect of the present invention provides an emulsification device, comprising the aforementioned multi-channel microfluidic emulsification membrane, wherein the multi-channel microfluidic emulsification membrane is encapsulated in a liquid phase chamber to seal the liquid phase chamber, and the emulsification device is provided with an input port for introducing a dispersed phase into the liquid phase chamber; preferably, when there are multiple liquid phase chambers, the number of input ports is the same as the number of liquid phase chambers, and they correspond one-to-one; the multiple liquid phase chambers are arranged in layers, and the liquid phase chambers not directly connected to the multi-channel microfluidic emulsification membrane are connected to the multi-channel microfluidic emulsification membrane through input channels, the outlet of the input channel is lower than the upper surface of the through holes of the multi-channel microfluidic emulsification membrane, the number of input channels is the same as the number of through holes of the multi-channel microfluidic emulsification membrane, and the input channels correspond one-to-one with the through holes of the multi-channel microfluidic emulsification membrane.

[0015] In the above technical solution, the multi-channel microfluidic emulsion film encapsulation method adopts one or more of the following methods for encapsulation and sealing: hot pressing, adhesive bonding, laser welding, ultrasonic welding, bolting, anodic bonding, and plasma bonding.

[0016] A third aspect of the present invention provides a method for membrane emulsification, the method comprising using the emulsification apparatus of claim 7, including the following steps:

[0017] (1) Place the emulsification device in the continuous phase emulsion, so that the dispersed phase and the continuous phase are respectively placed on both sides of the multi-channel microfluidic emulsion membrane;

[0018] (2) A dispersed phase is introduced into the liquid phase chamber. The dispersed phase enters the continuous phase through the through-holes of the multi-channel microfluidic emulsion membrane and completes continuous emulsification under the induction of emulsification control factors. Preferably, the emulsification control factors are selected from one or more of buoyancy, gravity, centrifugal force, electric field force, hydraulic shear force, magnetic force, temperature, interfacial tension, ultraviolet irradiation, infrared irradiation, and laser induction.

[0019] In the above technical solution, when the buoyancy factor is selected as the emulsification control factor, the density difference between the continuous phase and the dispersed phase is required to be greater than 0.2 g / ml, preferably within the range of 0.3-0.6 g / ml. During emulsion preparation, if the density of the dispersed phase is greater than that of the continuous phase, the multi-channel microfluidic emulsification membrane is placed horizontally, with the dispersed phase above the membrane and the continuous phase below it; otherwise, the positions of the dispersed phase and the continuous phase are reversed.

[0020] When gravity is selected as the emulsification control factor, the continuous phase is selected as the gas phase; during emulsion preparation, the multi-channel microfluidic emulsification membrane is placed horizontally, with the dispersed phase placed above the membrane and the continuous phase placed below the membrane;

[0021] When centrifugal force is selected as the emulsification control factor, a density difference is required between the continuous phase and the dispersed phase, and the density of the dispersed phase must be greater than that of the continuous phase. Preferably, the density difference ranges from 0.1 to 0.4 g / ml. During emulsion preparation, an additional centrifugal device needs to be introduced. The multi-channel microfluidic emulsification membrane is placed perpendicular to the centrifugal radius, with the dispersed phase placed closer to the centrifugal center and the continuous phase placed further away from the centrifugal center.

[0022] When the emulsification control factor is selected as the electric field force factor, the surface of the multi-channel microfluidic emulsion membrane needs to be gold-sprayed, or a metal-based multi-channel microfluidic emulsion membrane needs to be used, and an insulating material should be selected accordingly. During emulsion preparation, an electrostatic generation device is introduced, and a flat electrode with an area larger than the multi-channel microfluidic emulsion membrane is connected to the electrostatic generation device and placed horizontally above the multi-channel microfluidic emulsion membrane. At the same time, the multi-channel microfluidic emulsion membrane is grounded.

[0023] When the emulsification control factor is selected as a magnetic factor, magnetic materials need to be introduced into the continuous phase; during emulsion preparation, an additional parallel magnetic field perpendicular to the multi-channel microfluidic emulsion membrane is introduced.

[0024] The fourth aspect of the present invention provides the application of the aforementioned multichannel microfluidic emulsion membrane or the aforementioned emulsion device in the large-scale manufacturing of monodisperse emulsion droplets.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] 1) The present invention has an emulsion membrane with specific through holes, which realizes the use of membrane emulsification technology combined with microfluidic droplet technology. Through the independent setting of through holes, random arrangement or matrix arrangement, the emulsion membrane can meet the low energy consumption, high throughput and automated production of various small particle size and narrow particle size distribution microemulsions with unique manufacturing requirements under extremely high space utilization conditions (e.g., using an 8cm×8cm emulsion membrane, emulsion droplets with a particle size of 114.3±0.6μm can be prepared at a throughput of 71.2L / h).

[0027] 2) Based on microfluidic droplet technology, the through-pore structure of the present invention can achieve high-precision emulsification of emulsion level comparable to traditional dilute solution emulsification under emulsification conditions without the aid of external force, including but not limited to high viscosity polymer prepolymer solutions such as alginate and sodium carboxymethyl cellulose, to prepare high viscosity hydrogel emulsion droplets with small particle size and narrow particle size distribution; the emulsion droplet products obtained by the present invention have a particle size range of 0.01-10 mm and a particle size distribution of less than 5%.

[0028] 3) Unlike the passive emulsification scheme in traditional microfluidic droplet technology, this invention significantly reduces the control parameters required for droplet production. Based on control factors such as buoyancy, gravity, centrifugal force, electric field force, and magnetic force, monodisperse emulsions can be prepared without precisely limiting the input flow rate of the dispersed phase.

[0029] 4) Compared with the traditional high-precision membrane emulsification process for producing microspheres and microdroplets (CN 1939281A, CN105246580A), the multi-channel microfluidic emulsification membrane of the present invention is based on the microfluidic control mechanism of microfluidic droplet technology, which significantly reduces the supporting emulsification factors (shearing equipment, stirring equipment, tangential flow rate), simplifies the production process, and reduces equipment construction costs;

[0030] 5) When using the multi-channel microfluidic emulsion membrane of the present invention to continuously produce emulsion droplets, the continuous phase and the dispersed phase exhibit spontaneous separation effects under different production environments. Therefore, after emulsification, the dispersed phase emulsion droplets can automatically separate from the continuous phase, completing the preliminary separation step and eliminating the separation processes such as centrifugation and drying in the traditional emulsification process.

[0031] 6) The independent setting of the through holes in the emulsion film of the present invention can avoid the possibility of collision and fusion between multiple droplets when droplets are formed, so that the emulsification of each through hole is relatively independent, avoiding the problems of contamination between droplets and uneven product size. Attached Figure Description

[0032] Figure 1 A schematic diagram of the planar structure of a multichannel microfluidic emulsion membrane;

[0033] Figure 2 A schematic diagram of the three-dimensional structure of a multi-channel microfluidic emulsion membrane;

[0034] Figure 3 This is a three-dimensional schematic diagram of an emulsification device, where 1 is the input port, 2 is the liquid phase chamber, 3 is the multi-channel microfluidic emulsification membrane, and 4 is the input channel.

[0035] Figure 4 Micrographs of multichannel microfluidic emulsion membranes;

[0036] Figure 5 This describes the droplet formation on the surface of the multichannel microfluidic emulsion membrane with 30 through holes in Example 1.

[0037] Figure 6 These are micrographs showing the droplet formation within a single membrane pore during the preparation of a water-in-oil emulsion using a multi-channel microfluidic emulsion membrane in Example 1.

[0038] Figure 7 These are micrographs of water-in-oil emulsion products prepared using the multi-channel microfluidic emulsion membrane in Example 1;

[0039] Figure 8 These are micrographs showing the droplet formation in a single membrane pore during the preparation of water-in-oil emulsions using multi-channel microfluidic emulsion membranes with different pore sizes in Example 2.

[0040] Figure 9This is the particle size distribution of water-in-oil emulsion droplets prepared by emulsion membranes with different pore sizes in Example 2;

[0041] Figure 10 This is a product photo of the PEGDA600 gel obtained after 1 minute of preparation of the multi-channel microfluidic emulsion membrane in Example 3, wherein the upper white emulsion contains the obtained gel product;

[0042] Figure 11 Example 3 shows the size distribution of different gel products prepared using a multi-channel microfluidic emulsion membrane;

[0043] Figure 12 A three-dimensional structural diagram of a multi-channel microfluidic emulsion membrane, where X is the pore spacing in the first direction, Y is the pore spacing in the second direction, L is the length of the long side of the pore, h is the length of the short side, and H is the depth of the through pore (i.e., the membrane thickness).

[0044] Figure 13 This describes the droplet formation on the surface of the multi-channel microfluidic emulsion film with 300 through-holes in Example 1.

[0045] Figure 14 Schematic diagram of a multilayer emulsification device for the production of anionic and cation-structured microgels;

[0046] Figure 15 Schematic diagram of a multilayer emulsification device for producing core-shell microgels;

[0047] Figure 16 It is the cell-carrying microgel with yin-yang structure obtained by membrane preparation in Example 8;

[0048] Figure 17 It is a dual-fluorescent microgel with anionic and anionic structures prepared in Example 4;

[0049] Figure 18 This is the cell-carrying microgel prepared in Example 7, wherein the green bright spots are rat mesenchymal stem cells transfected with green fluorescent protein;

[0050] Figure 19 It is the Escherichia coli-loaded microgel prepared in Example 6;

[0051] Figure 20 It is the magnetic particle microgel prepared in Example 9;

[0052] Figure 21 The PMMA microgels prepared in Example 10;

[0053] Figure 22 It is the core-shell structured microgel prepared in Example 5;

[0054] Figure 23It is the polyethylene glycol dimethacrylate microgel prepared in Example 11;

[0055] Figure 24 This is a schematic diagram of the preparation apparatus in Example 10;

[0056] Figure 25 This is a schematic diagram of the preparation apparatus in Example 11;

[0057] Figure 26 These are electron microscope images of the planar structures of the different multichannel microfluidic emulsion membranes used in Example 12;

[0058] Figure 27 It is the one used in Example 12. Figure 26 The actual production effect diagram corresponding to the i-iii structure of the multi-channel microfluidic emulsion membrane is shown. Detailed Implementation

[0059] The present invention will be further described below with reference to specific embodiments, but this does not limit the present invention in any way.

[0060] The multi-channel microfluidic emulsion membrane disclosed in this invention combines the membrane emulsification concept with microfluidic droplet technology. Taking the preparation of hydrogel-based polymers as an example, it can continuously and stably prepare various hydrogel emulsion droplets and can automatically separate the continuous phase and the dispersed phase by means of the density difference between the liquid phases. The invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0061] The multichannel microfluidic emulsion membrane disclosed in this invention, such as Figure 1 As shown in Figure 2, the substrate has multiple through holes arranged in a rectangular array. The cross-section of each through hole is rectangular, with the shorter side length h being 0.005-1.5 mm and the ratio of the shorter side to the longer side being 1:2-1:10. The through holes are arranged in a rectangular array, and the spacing X between the through holes in the first direction is 0.2-20 times the length L of the longer side. The spacing Y between the through holes in the second direction is 0.4-20 times the length L of the longer side. Figure 12 The thickness of the multi-channel microfluidic emulsion film is 0.01mm-10mm, and the depth H of the through hole is more than 1 times the length of the long side. Figure 4 Micrograph of a multichannel microfluidic emulsion membrane.

[0062] like Figure 3As shown, the emulsification device includes a multi-channel microfluidic emulsifying membrane 3 and a liquid phase chamber 2. The multi-channel microfluidic emulsifying membrane is fixedly encapsulated in the liquid phase chamber by a clamp or other encapsulation method, sealing the liquid phase chamber and ensuring complete isolation between the liquid phase chamber side of the multi-channel microfluidic emulsifying membrane and the other side of the membrane, except for the through-holes. The emulsification device also includes an inlet port 1, which connects to an inlet pipe for introducing the dispersed phase into the liquid phase chamber. The entire emulsification device is placed in a storage tank containing a continuous phase, with both the multi-channel microfluidic emulsifying membrane and the liquid phase chamber submerged below the surface of the continuous phase. Figure 14 As shown in Figure 15, the emulsification device includes two liquid phase chambers arranged in layers. A multi-channel microfluidic emulsion membrane is fixedly encapsulated in the upper liquid phase chamber by a clamp or other encapsulation method, so that both the upper and lower liquid phase chambers are sealed. One side of the liquid phase chamber of the multi-channel microfluidic emulsion membrane is completely isolated from the other side of the multi-channel microfluidic emulsion membrane. Each liquid phase chamber is provided with an input port 1. Each input port is connected to an input pipe of a dispersed phase to introduce different dispersed phases into the two liquid phase chambers. The liquid phase chambers not directly connected to the multi-channel microfluidic emulsion membrane are connected to the multi-channel microfluidic emulsion membrane through an input channel 4. The outlet of the input channel 4 is lower than the upper surface of the through hole of the multi-channel microfluidic emulsion membrane. The number of input channels is consistent with the number of through holes of the multi-channel microfluidic emulsion membrane, and the input channels correspond one-to-one with the through holes of the multi-channel microfluidic emulsion membrane.

[0063] Taking a scenario where the continuous phase density is greater than the dispersed phase as an example, the dispersed phase is injected into the liquid phase chamber, and any residual air inside the chamber is purged. The dispersed phase is injected uniformly at a set flow rate. As it passes through the pores of the multi-channel microfluidic emulsion membrane, it propels itself with a constant curvature interface within the pores and rapidly expands upon reaching the pore outlet. Driven by the drag force of the dispersed phase and the interfacial tension between the two phases, the dispersed phase within the membrane pores rapidly enters the droplet at the outlet, causing a rapid decrease in the curvature of the interfacial interface within the membrane pores, thus completing the droplet detachment step. After detaching from the membrane surface, the droplet is enriched on the upper layer of the continuous phase due to the density difference between the two phases and remains stable under the action of the surfactant. Collecting the surface-enriched emulsion droplets yields the microemulsion product.

[0064] The multi-channel microfluidic emulsion membrane material can be one or more of the following: glass, silicon, metal, organic polymer, or organic-inorganic composite material. The processing methods can include laser, drilling, etching, and 3D printing. Figure 4 It can be processed in the form of integral molding, and hydrophilic or hydrophobic treatment is performed according to the characteristics of the target emulsion.

[0065] Therefore, the multi-channel microfluidic emulsion membrane based on microfluidic droplet technology and its applications disclosed in this invention have simple supporting equipment and a concise production process, and can be adapted to the preparation of different types of hydrogel microemulsions. Microfluidic droplet technology ensures the continuous formation of emulsion droplets, and the physical properties of the dispersed phase are used to achieve emulsion separation. Compared with traditional microfluidic droplet technology, this invention, combining membrane emulsification concepts and using a multi-channel microfluidic emulsion membrane design, significantly shortens the production time of microgel emulsions, simplifies the production process, and greatly increases production throughput while maintaining the microgel particle size distribution, providing a highly efficient platform for the production of polymer microemulsions.

[0066] Example 1: Water-in-oil droplets were prepared using multi-channel microfluidic emulsion membranes containing 30 and 300 through-holes, respectively.

[0067] The membrane pore size is 60×300μm, with a pore depth of 500μm and a pore spacing of 300μm in both the first and second directions. Ultrapure water is used as the dispersed phase, and HFE7500 containing 1% Krytox-COOH is used as the continuous phase.

[0068] The dispersed phase is pre-introduced into the liquid phase chamber through inlet 1 to purge the gas inside the dispersed phase. After the continuous phase is injected into the emulsification tank, the emulsification device is placed, with the emulsion membrane positioned horizontally and its pores facing upwards. The dispersed phase is introduced into the liquid phase chamber through inlet 1 at a flow rate of 1 ml / min. The droplet formation on the surface of the multi-channel microfluidic emulsion membrane containing 30 through-holes is as follows. Figure 5 As shown, the droplet formation on the surface of a multi-channel microfluidic emulsion film containing 300 through-holes is as follows: Figure 13 As shown, the droplet formation within a single emulsification pore is as follows: Figure 6 As shown. The emulsified droplets automatically accumulate on the surface of the emulsion tank, as... Figure 7 As shown. The product can be obtained by collecting a droplet of the upper emulsion.

[0069] Example 2: Preparation of water-in-oil droplets using multi-channel microfluidic emulsion membranes with through-holes of different sizes.

[0070] The membrane pore sizes are 500×150μm, 1000×200μm, 1440×340μm, 3000×600μm, 4000×800μm, 6000×1200μm, and 8000×1600μm, with pore depths ranging from 500 to 8000μm. The pore depth is equal to the length of the long side of the membrane pore, and the spacing between pores in the first and second directions is also equal to the length of the long side. The multi-channel microfluidic emulsifying membrane is sealed within a liquid phase chamber to obtain the emulsification device. Ultrapure water is used as the dispersed phase, and HFE7500 containing 1% Krytox-COOH is used as the continuous phase. The dispersed phase is pre-introduced through the inlet to purge the gas inside the liquid phase chamber. After the continuous phase is injected into the emulsification tank, the emulsification device is placed, with the multi-channel microfluidic emulsifying membrane placed horizontally and the pores facing upwards. The dispersed phase is introduced through the inlet, and the droplet formation at different pore sizes is shown below. Figure 8 As shown in the figure. The emulsion droplets automatically accumulate on the surface of the emulsion tank. The product is obtained by collecting the upper layer of emulsion droplets. The size distribution of emulsion droplets produced by membranes of different specifications is shown in the figure. Figure 9 As shown.

[0071] Example 3: Preparation of Alginate and Polyethylene Glycol Microgels Using Emulsion Membranes

[0072] The formulations for the prepolymer solution containing alginate (Alg) and polyethylene glycol diacrylate (PEGDA) are as follows:

[0073] Alginic acid: A 1% alginic acid solution containing 50mM calcium ethylenediaminetetraacetate;

[0074] Polyethylene glycol dimethacrylate: A 10% solution of polyethylene glycol dimethacrylate (PEGDA600) with a molecular weight of 600 containing 1% photoinitiator 2959.

[0075] Using the aforementioned hydrogel prepolymer as the dispersed phase and HFE7500 containing 1% Krytox-COOH as the continuous phase, a multi-channel microfluidic emulsion membrane with pore sizes of 2000 × 400 μm, a pore depth of 2000 μm, a pore spacing of 400 μm in the first direction, and a pore spacing of 800 μm in the second direction was sealed within a liquid phase chamber to obtain an emulsification device. The dispersed phase was pre-introduced through the input port to purge the gas inside the liquid phase chamber. After injecting the continuous phase into the emulsification tank, the emulsification device was placed, with the emulsion membrane horizontally positioned and its pores facing upwards. The dispersed phase was then introduced through the input port, and the emulsion-generated droplets automatically accumulated on the surface of the emulsion tank. Different curing methods were used to induce hydrogel curing (alginic acid: glacial acetic acid solution was added to the emulsification tank; PEGDA600: wavelength 365 nm, power 2 W / cm²). 2 The emulsion is irradiated with ultraviolet light, and after separation, the desired hydrogel product can be obtained, such as... Figure 10 As shown. Size distribution of different types of gels as follows. Figure 11 As shown.

[0076] Example 4: Preparation of Janus-structured alginate microgels using an integrated multilayer emulsion membrane

[0077] The formulation of the alginate (Alg) prepolymer solution is as follows:

[0078] Alginic acid A: A 1% 5-aminofluorescein-modified alginic acid solution containing 50 mM calcium ethylenediaminetetraacetate;

[0079] Alginic acid B: A 1% Rhodamine B-modified alginic acid solution containing 50 mM calcium ethylenediaminetetraacetate;

[0080] The aforementioned hydrogel prepolymer was used as the dispersed phase, and HFE7500 containing 1% Krytox-COOH was used as the continuous phase. The membrane pore size was 2000 × 400 μm, with a pore depth of 2000 μm and a pore spacing of 2000 μm in both the first and second directions. Alginic acid A and alginic acid B were placed in two separate liquid phase chambers, arranged vertically. The upper chamber of alginic acid A was directly connected to the multi-channel microfluidic emulsion membrane, and the lower chamber of alginic acid B was connected to each through-pore of the multi-channel microfluidic emulsion membrane through an 800 × 400 μm input channel. The outlet of the input channel was lower than the upper surface of the multi-channel microfluidic emulsion membrane. Figure 14 An emulsification device is obtained by sealing a multi-channel microfluidic emulsion membrane in an upper liquid phase chamber. Dispersed phases are pre-introduced into two liquid phase chambers through different inlet ports to purge air. After injecting the continuous phase into the emulsification tank, the emulsification device is placed inside, with the emulsion membrane horizontally positioned and its pores facing upwards. Alginic acid A and alginic acid B are introduced into the two liquid phase chambers through different inlet ports. By controlling the flow rates of the different dispersed phases, multi-lobed microgels with different chamber ratios are obtained. The emulsion-generated droplets automatically accumulate on the surface of the emulsion tank. Glacial acetic acid solution is added to the emulsification tank to induce cross-linking of the anionic and cation-structured alginate microgels. After separation, the desired hydrogel product is obtained, such as... Figure 17 As shown.

[0081] Example 5: Preparation of Alginate Core-Shell Structured Microgels Using an Integrated Multilayer Emulsion Membrane

[0082] The formulation of the alginate (Alg) shell prepolymer solution is: a 1% 5-aminofluorescein modified alginate solution containing 50mM calcium ethylenediaminetetraacetate.

[0083] The core prepolymer solution is formulated as follows: a 10% rhodamine-modified dextran solution;

[0084] Using the aforementioned prepolymer as the dispersed phase, HFE7500 containing 1% Krytox-COOH was used as the continuous phase. The membrane pore size was 2000 × 400 μm, with a pore depth of 2000 μm and a pore spacing of 2000 μm in both the first and second directions. The shell prepolymer and core prepolymer were placed in different liquid phase chambers. The shell prepolymer chamber was connected to the multi-channel microfluidic emulsion membrane, and the core prepolymer chamber was connected to each through-hole of the multi-channel microfluidic emulsion membrane via an input channel. The outlet of the input channel was below the upper surface of the multi-channel microfluidic emulsion membrane, and the input channel was located at the center of each through-hole. Figure 15 This design ensures that the shell prepolymer enters from both sides of the through-hole, while the core prepolymer enters from the middle. Each through-hole contains three 500×400μm emulsification channels, with the shell prepolymer entering through the two side channels and the core prepolymer entering through the middle channel connected to the input channel. The multi-channel microfluidic emulsion membrane is encapsulated in a sealed liquid phase chamber to obtain the emulsification device. Dispersed phase is pre-introduced into two liquid phase chambers through different input holes to purge air from the liquid phase chambers. After injecting the continuous phase into the emulsification tank, the emulsification device is placed, with the emulsion membrane horizontally and the pores facing upwards. Dispersed phase is then introduced into the two liquid phase chambers through different input holes. The emulsion-generated droplets automatically accumulate on the surface of the emulsion tank. Glacial acetic acid solution is added to the emulsification tank to induce cross-linking of the anionic and cation-structured alginate microgels. After separation, the desired hydrogel product is obtained, such as... Figure 22 As shown.

[0085] Example 6: Preparation of Alginate Microgels Carrying Escherichia coli Using an Integrated Multichannel Microfluidic Emulsion Membrane

[0086] The alginic acid (Alg) prepolymer formulation is as follows: E. coli concentration is 10. 10 / ml, a 1% alginate solution containing 50mM calcium ethylenediaminetetraacetate;

[0087] Using the aforementioned hydrogel prepolymer as the dispersed phase and HFE7500 containing 1% Krytox-COOH as the continuous phase, the membrane pore size was 3000 × 1500 μm, with a pore depth of 10000 μm and a pore spacing of 200 μm in both the first and second directions. Similar to Example 3, glacial acetic acid solution was added to the emulsification tank to induce crosslinking of the alginate microgel. After separation, the desired hydrogel product was obtained. Figure 19 As shown.

[0088] Example 7: Preparation of Alginate Microgels Loaded with Rat Mesenchymal Stem Cells Using an Integrated Multichannel Microfluidic Emulsion Membrane.

[0089] The alginic acid (Alg) prepolymer formulation is as follows: the concentration of green fluorescent protein-transfected rat mesenchymal stem cells is 4 x 10⁻⁶. 6 / ml, a 1% alginate solution containing 50mM calcium ethylenediaminetetraacetate;

[0090] Using the aforementioned hydrogel prepolymer as the dispersed phase and HFE7500 containing 1% Krytox-COOH as the continuous phase, the membrane pore size was 50 × 5 μm with a pore depth of 50 μm and a pore spacing of 1000 μm in both the first and second directions. Similar to Example 3, glacial acetic acid solution was added to the emulsification tank to induce crosslinking of the anionic and cation-chain alginate microgels. After separation, the desired hydrogel product was obtained. Figure 18 As shown.

[0091] Example 8: Preparation of Janus-structured cell-carrying microgels using an integrated multi-channel microfluidic emulsion membrane.

[0092] The formulation of the alginate (Alg) prepolymer solution is as follows:

[0093] Alginic acid A: A 1% 5-aminofluorescein-modified alginic acid solution containing 50 mM calcium ethylenediaminetetraacetate, containing 2 × 10 6 / ml rat mesenchymal stem cells;

[0094] Alginic acid B: An alginate solution modified with an arginine-glycine-aspartic acid fragment containing 50 mM calcium ethylenediaminetetraacetate, containing 2 × 10 6 / ml of HeLa cells transfected with green fluorescent protein;

[0095] The aforementioned hydrogel prepolymer was used as the dispersed phase, and HFE7500 containing 1% Krytox-COOH was used as the continuous phase. The membrane pore size was 2000 × 400 μm, with a pore depth of 2000 μm and a pore spacing of 2000 μm in both the first and second directions. Alginic acid A and alginic acid B were placed in different liquid phase chambers. The chamber of alginic acid A was directly connected to the multi-channel microfluidic emulsion membrane, while the chamber of alginic acid B was connected to each through-pore of the multi-channel microfluidic emulsion membrane through an 800 × 400 μm input channel. The outlet of the input channel was lower than the upper surface of the multi-channel microfluidic emulsion membrane. Figure 14 Similar to Example 4, glacial acetic acid solution is added to the emulsification tank to induce cross-linking of the anionic and cation-structured alginate microgels. After separation, the desired cell-loaded microgel product can be obtained, such as... Figure 16 As shown, the nuclei of rat mesenchymal stem cells were stained with DAPI, showing blue fluorescence.

[0096] Example 9: Preparation of Alginate Microgels Carrying Magnetic Particles Using an Integrated Single-Layer Multi-Channel Microfluidic Emulsion Membrane

[0097] The prepolymer solution of alginate (Alg) is formulated as follows: a 1% alginate solution containing 1% Fe3O4 nanoparticles and 50mM calcium ethylenediaminetetraacetate.

[0098] Using the aforementioned hydrogel prepolymer as the dispersed phase and soybean oil containing 1% TWEEN-80 as the continuous phase, a membrane with pore sizes of 500 × 100 μm and a depth of 1000 μm was used. The spacing between pores in both the first and second directions was 1000 μm. The multi-channel microfluidic emulsifying membrane was sealed within a liquid phase chamber to obtain an emulsification device. The input port of the emulsification device was connected to the input pipe of the dispersed phase, and the dispersed phase was pre-introduced to purge any gas inside. After injecting the continuous phase into the emulsification tank, the emulsification tank was placed above a neodymium magnet. The emulsification device was placed in the emulsification tank, with the multi-channel microfluidic emulsifying membrane horizontally positioned, pores facing downwards and directly opposite the neodymium magnet. A parallel magnetic field was introduced perpendicular to the multi-channel microfluidic emulsifying membrane. The dispersed phase was introduced through the input port, and the emulsion-generated droplets automatically accumulated at the bottom of the emulsification tank. Glacial acetic acid solution was added to the emulsification tank to induce cross-linking of the alginate microgel. After separation, the desired hydrogel product was obtained, such as... Figure 20 As shown.

[0099] Example 10 uses an integrated multi-channel microfluidic emulsion membrane to prepare polymethyl methacrylate (PMMA) microparticles based on electric field force.

[0100] The prepolymer formulation for polymethyl methacrylate (PMMA) is: a toluene solution containing 1% by mass of photoinitiator 1173 and 20% by mass of methyl methacrylate;

[0101] Using the aforementioned prepolymer as the dispersed phase, and HFE7500 fluorinated liquid containing 1% perfluoropolyether surfactant as the continuous phase, the membrane pore size is 400×80μm, with a pore depth of 1000μm and a pore spacing of 600μm in both the first and second directions. The membrane surface is silver-plated. After sealing in the liquid phase chamber, an emulsification device is obtained. The input port of the emulsification device is connected to the input pipe of the dispersed phase. The dispersed phase is pre-introduced to purge the gas inside, and a grounding wire is introduced into the liquid phase chamber of the dispersed phase to ground it. After injecting the continuous phase into the emulsification tank, the emulsification tank is placed on a high-voltage plate electrode, and the voltage is adjusted to 20kV. The emulsification device is placed in the emulsification tank, ensuring that the multi-channel microfluidic emulsification membrane is placed horizontally with the pores facing downwards. Figure 24 As shown. The input dispersed phase emulsifies, and the resulting droplets automatically accumulate at the bottom of the emulsification tank. The emulsion at the bottom of the tank is irradiated with ultraviolet light, and after separation, the desired microparticle product can be obtained, such as... Figure 21 As shown.

[0102] Example 11 uses a single-layer multi-channel microfluidic emulsion membrane to prepare polyethylene glycol dimethacrylate (PEGDA) microparticles using centrifugal force in a high-throughput manner.

[0103] The prepolymer formulation for polyethylene glycol dimethacrylate (PEGDA) is: a solution of ethylene glycol dimethacrylate (EGDMA) containing 1% by mass of photoinitiator 614;

[0104] Using the aforementioned prepolymer as the dispersed phase and an aqueous solution containing 20% ​​polyvinyl alcohol as the continuous phase, the membrane pore size is 400 × 80 μm, with a pore depth of 1000 μm and a pore spacing of 600 μm in both the first and second directions. After sealing in a liquid phase chamber, an emulsification device is obtained. The inlet of the emulsification device is connected to the inlet pipe of the dispersed phase, and the dispersed phase is pre-introduced to purge the gas inside the dispersed phase. The emulsification tank is placed on a centrifuge, and the emulsification device is placed in the emulsification tank, with the multi-channel microfluidic emulsification membrane perpendicular to the centrifugal radius. The centrifuge is started, the dispersed phase is introduced, and the emulsification process is initiated. Figure 25 As shown. After emulsification is complete, the centrifuge is turned off, and the emulsion product naturally settles to the bottom of the emulsification tank. The emulsion at the bottom of the tank is then irradiated with ultraviolet light, and after separation, the desired microparticle product can be obtained, such as... Figure 23 As shown.

[0105] Example 12: Preparation of water-in-oil droplets using a multichannel microfluidic emulsion membrane with irregularly arranged rectangular pores.

[0106] The membrane pore size is 300×60μm, and the pore depth is 500μm. Each through-hole is independently and randomly arranged, such as... Figure 26 As shown, Figure 26 Three types of emulsifying membranes formed by random arrangement were demonstrated. Each of these three multi-channel microfluidic emulsifying membranes was sealed within a liquid phase chamber to obtain an emulsification device. Ultrapure water was used as the dispersed phase, and HFE7500 containing 1% Krytox-COOH was used as the continuous phase. The dispersed phase was pre-introduced through the inlet to purge the gas inside the liquid phase chamber. After the continuous phase was injected into the emulsification tank, the emulsification device was placed inside, with the multi-channel microfluidic emulsifying membrane horizontally and its pores facing upwards. The dispersed phase was then introduced through the inlet. The emulsion-generated droplets automatically accumulated on the surface of the emulsion tank. The product was obtained by collecting the upper layer of emulsion droplets. The droplet size distribution produced by the membrane structures formed by the random arrangement of the three different rectangular pores was the same, and all were similar to the droplet products obtained by an array of through-holes of the same specification. Figure 13 The droplet size difference coefficients are all <3%, such as Figure 27 As shown.

[0107] For anyone skilled in the art, many possible variations and modifications can be made to the technical solutions of this invention, or equivalent embodiments can be modified based on the disclosed technical content, without departing from the scope of the technical solutions of this invention. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this invention without departing from the content of the technical solutions of this invention should still fall within the protection scope of the technical solutions of this invention.

Claims

1. A multichannel microfluidic emulsion membrane for manufacturing monodisperse emulsion droplets, characterized in that, It includes at least one through hole, the through hole having a rectangular cross-section with a short side length of 0.005-1.5 mm and a side length ratio of the short side to the long side of 1:2-1:10; The through holes are arranged in a rectangular array. The spacing between the through holes in the first direction is 0.2-20 times the length of the long side, and the spacing between the through holes in the second direction is 0.4-20 times the length of the long side. The first direction is the direction of the long side, and the second direction is the direction of the short side. The through hole is processed by laser, drilling, etching, 3D printing or integral molding; The thickness of the multi-channel microfluidic emulsion membrane is 0.01mm-10mm, and the depth of the through hole is more than 1 times the length of the long side; The through-hole array is located in the center of the multi-channel microfluidic emulsion membrane plane, with a blank area left at the edge of the membrane without through-holes. The straight-line distance between the through-holes on the outer side of the through-hole array and the edge of the membrane is greater than twice the length of the long side.

2. The multi-channel microfluidic emulsion membrane according to claim 1, characterized in that, The shorter side of the cross-section is 0.01-0.5mm.

3. The multi-channel microfluidic emulsion membrane according to claim 1, characterized in that, The multichannel microfluidic emulsion membrane is made of one or more of the following materials: glass, silicon, metal, ceramic, organic polymer, or organic-inorganic composite material.

4. A device for preparing monodisperse emulsion droplets based on a multi-channel microfluidic emulsion membrane, characterized in that, The device includes the multi-channel microfluidic emulsion membrane of claim 1, wherein the multi-channel microfluidic emulsion membrane is encapsulated in a liquid phase chamber to seal the liquid phase chamber, and the monodisperse emulsion droplet preparation device is provided with an inlet port for introducing the dispersed phase into the liquid phase chamber.

5. The monodisperse emulsion droplet preparation apparatus according to claim 4, characterized in that, When there are multiple liquid phase chambers, the number of input holes is the same as the number of liquid phase chambers, and they correspond one-to-one. The multiple liquid phase chambers are arranged in layers. Liquid phase chambers that are not directly connected to the multi-channel microfluidic emulsion membrane are connected to the multi-channel microfluidic emulsion membrane through input channels. The outlet of the input channel is lower than the upper surface of the through hole of the multi-channel microfluidic emulsion membrane. The number of input channels is the same as the number of through holes of the multi-channel microfluidic emulsion membrane, and the input channels correspond one-to-one with the through holes of the multi-channel microfluidic emulsion membrane. The input channel is placed at the center of each through hole.

6. A method for large-scale preparation of monodisperse emulsion droplets, characterized in that, The method includes using the monodisperse emulsion droplet preparation apparatus of claim 4 or 5, comprising the following steps: (1) Place the monodisperse emulsion droplet preparation device in the continuous phase, so that the dispersed phase and the continuous phase are placed on both sides of the multichannel microfluidic emulsion membrane; (2) The dispersed phase is introduced into the liquid phase chamber and enters the continuous phase through the through-hole of the multi-channel microfluidic emulsion membrane. Continuous emulsification is completed under the induction of emulsification control factors. The emulsification control factors are selected from one or more of buoyancy, gravity, centrifugal force, electric field force, and magnetic force.

7. The method for large-scale preparation of monodisperse emulsion droplets according to claim 6, characterized in that, When the emulsification control factor is buoyancy, the density difference between the continuous phase and the dispersed phase is greater than 0.2 g / ml; if the density of the dispersed phase is greater than that of the continuous phase, the multi-channel microfluidic emulsification membrane is placed horizontally, with the dispersed phase above the membrane and the continuous phase below the membrane; otherwise, the positions of the dispersed phase and the continuous phase are reversed. When the emulsification control factor is gravity, the continuous phase is selected as the gas phase; the multi-channel microfluidic emulsification membrane is placed horizontally, with the dispersed phase placed above the membrane and the continuous phase placed below the membrane. When the emulsification control factor is centrifugal force, centrifugal force is provided by a centrifuge, the density of the dispersed phase is greater than that of the continuous phase, and the density difference ranges from 0.1 to 0.4 g / ml; the multi-channel microfluidic emulsification membrane is placed perpendicular to the centrifugal radius, the dispersed phase is placed closer to the centrifugal center, and the continuous phase is placed further away from the centrifugal center. When the emulsification control factor is an electric field factor, an electric field is generated by an electrostatic generation device. The surface of the multi-channel microfluidic emulsion film is treated with gold sputtering, or a metal-based multi-channel microfluidic emulsion film is used, with the continuous phase being an insulating material. A flat electrode with an area larger than the multi-channel microfluidic emulsion film is connected to the electrostatic generation device and placed horizontally above the multi-channel microfluidic emulsion film, while the multi-channel microfluidic emulsion film is grounded. When the emulsification control factor is a magnetic factor, magnetic materials are introduced into the continuous phase, and a parallel magnetic field is introduced perpendicular to the multi-channel microfluidic emulsion film.

8. The method for large-scale preparation of monodisperse emulsion droplets according to claim 6, characterized in that, When the emulsification control factor is buoyancy, the density difference between the continuous phase and the dispersed phase ranges from 0.3 to 0.6 g / ml.

9. The application of the multichannel microfluidic emulsion membrane of claim 1 in the large-scale manufacturing of monodisperse emulsion droplets.

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