A microfluidic device and method for multi-field synergistic emulsification

Abstract

The application discloses a kind of microfluidic device and method of multi-field synergistic emulsification, including cabin, cabin includes microfluidic chip, electric field generating device and magnetic field generating device, cabin is connected high-precision injection pump by pressure sensor, flow sensor, inlet valve, intermediate container and injection pump valve;Cabin is connected confining pressure tracking pump by pressure sensor and back pressure pump valve;Cabin is connected back pressure pump by pressure sensor, flow sensor;Back pressure pump connects fluid collector;High-precision injection pump, confining pressure tracking pump, back pressure pump and high-resolution microscope are connected computer control end;Electric heating wire is provided in cabin;The application uses the above-mentioned microfluidic device and method of multi-field synergistic emulsification, can be accurately regulated and controlled emulsification process in microfluidic system by the synergistic effect of electric field and magnetic field, so as to optimize the particle size distribution, stability and generation rate of emulsion.

Description

Technical Field

[0001] This invention relates to the field of microfluidic device technology, and in particular to a microfluidic device and method for multi-field synergistic emulsification. Background Technology

[0002] Emulsification technology is widely used in chemical, pharmaceutical, and food processing industries. Emulsification refers to the process by which two normally immiscible liquids (such as oil and water) are combined through external forces to form a uniformly dispersed droplet system. The emulsification process typically requires the addition of emulsifiers (such as surfactants) to reduce the interfacial tension between the droplets, helping them maintain a stable dispersion. The resulting system is called an emulsion, which is generally classified into water-in-oil (O / W) and oil-in-water (W / O) types. During emulsification, the size, morphology, and stability of the droplets play a crucial role. In practical applications, the size, morphology, and stability of the droplets are limited by various factors, including the physical properties of the fluid (such as viscosity and surface tension) and flow conditions (such as fluid shear stress and flow velocity).

[0003] Existing emulsification technologies, including high-shear emulsification, ultrasonic emulsification, electric field emulsification, and solvent emulsification, primarily rely on single shear stress or flow rate control to generate droplets. However, these methods struggle to precisely control droplet size and morphology, especially in high-viscosity or non-Newtonian fluid systems. The droplet formation process suffers from uneven size distribution and interfacial instability, affecting the final emulsion quality. Furthermore, during emulsification, droplets may coalesce, merge, or stratify, leading to uneven emulsion particle size distribution, reduced emulsification effectiveness, and even impacting product quality and performance.

[0004] Current research has explored the influence of multiple fields, such as electric and magnetic fields, on the emulsification process. However, the limitations of a single field make it difficult to improve the control precision of droplet formation. Although some studies have attempted to combine external fields such as electric and magnetic fields for emulsification regulation, the control methods of these fields are often singular and difficult to coordinate, making it difficult to achieve ideal control over droplet size, morphology, and stability during the emulsification process. Existing technologies have failed to effectively achieve synergistic regulation of multiple fields and typically lack precise control over the effects of multiple fields, making droplet formation and stability control during the emulsification process a significant challenge.

[0005] Microfluidic technology has wide applications in emulsification, dispersion, and reaction control, and microfluidic devices can achieve droplet generation and dispersion at a microscale through precise fluid control techniques. Simultaneously, microfluidics can be effectively combined with electric and magnetic fields to form multi-field synergistic regulation. To overcome the limitations of existing technologies, this patent proposes a multi-field synergistic emulsification microfluidic device. Through adjustable electromagnetic field coupling control, it precisely regulates droplet generation dynamics, optimizes droplet size, interface stability, and morphological evolution, thereby significantly improving emulsification accuracy and efficiency. The synergistic effect of magnetic and electric fields provides higher control precision than a single field, effectively overcoming the problems of droplet inhomogeneity and poor stability in traditional emulsification methods. Furthermore, this patent can adapt to more complex fluid systems, providing a more efficient, precise, and controllable solution for the development of emulsification technology. Summary of the Invention

[0006] The purpose of this invention is to provide a microfluidic device and method for multi-field synergistic emulsification, which can precisely control the emulsification process in a microfluidic system through the synergistic effect of electric and magnetic fields, thereby optimizing the particle size distribution, stability and formation rate of the emulsion.

[0007] This invention provides a microfluidic device and method for multi-field synergistic emulsification, comprising a chamber, which includes a microfluidic chip, an electric field generating device, and a magnetic field generating device. The chamber is connected to a high-precision injection pump via a pressure sensor, a flow sensor, an inlet valve, an intermediate container, and an injection pump valve. The chamber is also connected to a confining pressure tracking pump via a pressure sensor and a back pressure pump valve. Furthermore, the chamber is connected to a back pressure pump via a pressure sensor and a flow sensor. The back pressure pump is connected to a fluid collector. The high-precision injection pump, the confining pressure tracking pump, the back pressure pump, and a high-resolution microscope are connected to a computer control unit. A heating wire is installed within the chamber.

[0008] Preferably, the microfluidic chip has two inlet branches and one outlet branch.

[0009] Preferably, the electric field generating device includes electrodes and a first frequency-modulated power supply. The electrodes are located on both sides of the fluid channel inside the chamber, and the first frequency-modulated power supply is connected to the electrodes.

[0010] Preferably, the magnetic field generating device includes a slide rail, an electromagnet, and a second frequency-modulated power supply, with the electromagnet mounted on the slide rail.

[0011] Preferably, it includes the following steps:

[0012] Step S1: Initialize the device and ensure a normal connection;

[0013] Confirm that the microfluidic chip, electric field generator, magnetic field generator, high-precision injection pump, confining pressure tracking pump, high-resolution microscope, computer control terminal, back pressure pump, fluid collector, pressure sensor, injection pump valve, inlet valve, back pressure pump valve, outlet valve, and heating wire are properly connected.

[0014] Step S2: Preparation and inflow of fluid;

[0015] The raw materials required to prepare the target emulsion include a continuous phase and a dispersed phase. The liquid storage pipe in the high-precision injection pump is connected to the inlet branch of the microfluidic chip. The two inlet branches of the microfluidic chip correspond to the inlet branches of the continuous phase and the dispersed phase, respectively.

[0016] Step S3: Multi-field synergistic regulation;

[0017] Step S4: Monitoring and data acquisition of the emulsification process of the fluid;

[0018] A real-time high-resolution microscope is activated to dynamically observe the droplet formation process. Image analysis is used to collect and record key data of the droplets during the emulsification process. Pressure fluctuations in the channel during the emulsification process are monitored in real time through a pressure sensor and a back pressure pump.

[0019] Step S5: Collect fluid.

[0020] The fluid collector was activated to guide the generated emulsion from the outlet channel to the storage container for segmented collection, and the generation conditions and parameters of each sample were recorded; the particle size distribution and long-term stability of the emulsion samples were measured using a particle size analyzer and dynamic light scattering (DLS) technology.

[0021] Step S6: Equipment cleaning and maintenance;

[0022] Shut down all devices and drain any remaining liquid from the fluid channels; clean the microfluidic chip, high-precision injection pump, and fluid channels with a cleaning solvent to avoid cross-contamination; check the operating status of the electric and magnetic field devices, and after ensuring there are no abnormalities, turn off the system power to complete the operation.

[0023] Preferably, in step S1, the heating wire is adjusted to set the temperature of the microfluidic chip to the target value; the pressure sensor and back pressure pump are started to perform calibration.

[0024] Preferably, in step S2, the flow rate and flow parameters of the high-precision injection pump are set, and the high-precision injection pump is started to accurately deliver the continuous phase and the dispersed phase to the microfluidic chip.

[0025] Preferably, in step S3, the electric field generating device is activated by adjusting the electrode position, intensity, and frequency; the magnetic field generating device is activated by using a slide rail to precisely position the electromagnet and adjusting the second frequency-modulated power supply.

[0026] Therefore, the present invention employs a microfluidic device and method for multi-field synergistic emulsification, which can precisely control the emulsification process in a microfluidic system through the synergistic effect of electric and magnetic fields, thereby optimizing the particle size distribution, stability, and formation rate of the emulsion.

[0027] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the overall structure of a microfluidic device and method for multi-field synergistic emulsification according to the present invention.

[0029] Figure 2 This is a schematic diagram of the electric field generation device of the microfluidic device and method for multi-field synergistic emulsification according to the present invention. Detailed Implementation

[0030] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0031] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0032] The terms "first," "second," and similar words used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0033] Example 1

[0034] like Figures 1-2 As shown, this invention discloses a microfluidic device and method for multi-field synergistic emulsification, comprising a chamber. The chamber includes a microfluidic chip, an electric field generating device, and a magnetic field generating device. The microfluidic chip has two inlet branches and one outlet branch. The electric field generating device includes electrodes and a first frequency-tuned power supply. The electrodes are located on both sides of the fluid channel within the chamber, and the first frequency-tuned power supply is connected to the electrodes. The magnetic field generating device includes a slide rail, an electromagnet, and a second frequency-tuned power supply. The electromagnet is mounted on the slide rail.

[0035] The chamber is connected to a high-precision injection pump via pressure sensors, flow sensors, inlet valves, intermediate containers, and injection pump valves; the chamber is connected to a confining pressure tracking pump via pressure sensors and back pressure pump valves; the chamber is connected to a back pressure pump via pressure sensors and flow sensors; the back pressure pump is connected to a fluid collector; the high-precision injection pump, confining pressure tracking pump, back pressure pump, and high-resolution microscope are connected to a computer control terminal; heating wires are installed inside the chamber.

[0036] Includes the following steps:

[0037] Step S1: Initialize the device and ensure a normal connection;

[0038] Confirm that the microfluidic chip, electric field generator, magnetic field generator, high-precision injection pump, confining pressure tracking pump, high-resolution microscope, computer control terminal, back pressure pump, fluid collector, pressure sensor, injection pump valve, inlet valve, back pressure pump valve, outlet valve, and heating wire are properly connected.

[0039] In step S1, the heating wire is adjusted to set the microfluidic chip temperature to the target value to ensure the stability of the emulsification process. The pressure sensor and back pressure pump are activated for calibration to ensure the accuracy of fluid pressure monitoring.

[0040] Step S2: Preparation and inflow of fluid;

[0041] The raw materials required for preparing the target emulsion include the continuous phase and the dispersed phase, and their physicochemical properties must be ensured to meet the requirements of the emulsification experiment. The reservoir pipe in the high-precision injection pump is connected to the inlet branch of the microfluidic chip; the two inlet branches of the microfluidic chip correspond to the inlet branches of the continuous phase and the dispersed phase, respectively.

[0042] In step S2, the flow rate and volume parameters of the high-precision injection pump are set to ensure that the flow ratio of the continuous phase and the dispersed phase meets the experimental requirements. The high-precision injection pump is then started to precisely deliver the continuous phase and the dispersed phase to the microfluidic chip.

[0043] Step S3: Multi-field synergistic regulation;

[0044] In step S3, the electric field generating device is activated, and the electrode position, intensity, and frequency are adjusted to set appropriate electric field parameters, enabling the fluid to form a stable electric field response within the microfluidic channel. The magnetic field generating device is then activated, using a sliding rail to precisely position the electromagnet and adjusting the second frequency-modulated power supply. This ensures the optimized effect of the magnetic field on the emulsification process. A microscope system combined with high-speed imaging technology is used to monitor the dynamic control effect of the electromagnetic field on the droplet formation process in real time, accurately analyzing changes in droplet size, shear fracture mode, and stability. The field parameters are then fine-tuned based on the droplet formation situation to obtain the target droplet size and morphology.

[0045] Step S4: Monitoring and data acquisition of the emulsification process of the fluid;

[0046] A real-time high-resolution microscope is activated to dynamically observe the droplet formation process, including droplet size, morphology, and distribution. Image analysis is used to acquire and record key droplet data during emulsification, ensuring the traceability of experimental results. Pressure sensors and a backpressure pump are used to monitor pressure fluctuations within the channel during emulsification in real time, ensuring the stability of the emulsification process.

[0047] Step S5: Collect fluid.

[0048] Start the fluid collector to guide the generated emulsion from the outlet channel to the storage container for segmented collection, and record the generation conditions and parameters of each sample; use a particle size analyzer and dynamic light scattering (DLS) technology to measure the particle size distribution and long-term stability of the emulsion sample; ensure that it meets the experimental objectives.

[0049] Step S6: Equipment cleaning and maintenance;

[0050] Shut down all devices and drain any remaining liquid from the fluid channels; clean the microfluidic chip, high-precision injection pump, and fluid channels with a cleaning solvent to avoid cross-contamination; check the operating status of the electric and magnetic field devices, and after ensuring there are no abnormalities, turn off the system power to complete the operation.

[0051] Confining pressure refers to the pressure applied externally to a microfluidic chip. Its main function is to balance or regulate the internal pressure of the chip through external pressure, thereby preventing damage caused by excessive internal pressure. It also enables the creation of a high-pressure environment to simulate specific experimental conditions, and through dynamic adjustment, ensures the stability and accuracy of pressure during experiments, while also assisting in temperature control. Confining pressure is a crucial technical means to ensure the safety, stability, and accuracy of microfluidic experiments.

[0052] To optimize droplet size, morphology, and stability during emulsification, the adjustment of the electric field strength needs to be based on the following experimental conditions and factors:

[0053] Based on the mechanism of electric field action:

[0054] The effect of electric field on charged particles / polar molecules: Charged particles, polar molecules or electrolyte components in fluids will undergo directional movement under the action of electric field (such as electrophoresis effect, electroosmosis effect), affecting the stability of emulsion interface.

[0055] The effect of electric field on droplet formation: The electric field strength determines the change of interfacial tension at the interface between the dispersed and continuous phases, thus affecting the droplet formation rate, size uniformity, and stability.

[0056] Specific adjustment criteria: The adjustment of electric field strength mainly relies on the following key parameters: Dielectric properties of the fluid: Since different liquids have different dielectric constants, the intensity of the electric field should be optimized according to the dielectric properties of the fluid. For example, liquids with higher dielectric constants (such as the aqueous phase) are more sensitive to the electric field, while liquids with lower dielectric constants (such as the oil phase) may require a stronger electric field to produce a significant effect.

[0057] Droplet size and morphology requirements: The real-time microscopy system monitors droplet formation and adjusts the electric field strength to optimize droplet size and morphology. If the electric field is too strong, droplets may become smaller or even break up, resulting in an unstable emulsion; if the electric field is too weak, droplets may be larger, leading to decreased uniformity. Therefore, the electric field parameters should be adjusted based on feedback from the microscopy system.

[0058] The interplay between flow velocity and fluid shear stress: High-precision injection pumps control fluid flow velocity, and there is an interaction between flow velocity and electric field strength. At low flow velocities, a relatively small electric field strength can influence the droplet interface morphology; at high flow velocities, a higher electric field strength is required to compensate for hydrodynamic effects and stabilize droplet formation.

[0059] The Influence of Experimental Temperature: Since the temperature control system regulates the temperature of the microfluidic chip, and temperature affects the viscosity and conductivity of the liquid, thus influencing the effectiveness of the electric field, the electric field strength should be re-optimized at different temperatures. The Coordinating Effect of the Magnetic Field: The synergistic effect of the electric and magnetic fields is employed. The magnetic field influences the distribution of droplets containing magnetic particles. If the magnetic field is strong, the electric field strength needs to be appropriately reduced to avoid excessively disturbing droplet stability. Conversely, if the magnetic field is weak, the electric field strength can be appropriately increased to enhance the control over the droplet formation process.

[0060] Specific adjustment methods: Based on the above, the electric field strength is adjusted as follows: 1. Initial electric field range setting: Based on the dielectric properties of the fluid and the experimental objectives, set an initial electric field strength (e.g., 100V / cm~500V / cm). 2. Real-time adjustment: Observe the droplet size and morphology using a microscope system. If the droplets are too large, appropriately increase the electric field strength; if the droplets are unstable, decrease it. 3. Coordination with flow rate and magnetic field: Gradually adjust the relative strength of the electric and magnetic fields to ensure uniform and stable droplet formation. Summary: The adjustment of the electric field strength mainly depends on the dielectric properties of the fluid, droplet size requirements, flow rate and fluid shear stress, experimental temperature, and the interaction of the magnetic field. The adjustment method relies on microscope monitoring and experimental parameter optimization to achieve the best emulsification effect. Magnetic field adjustment: The following is a detailed analysis of how to optimize the magnetic field parameters (position, intensity, direction) and the frequency of the frequency-tuned power supply according to experimental conditions. a. Based on the mechanism of magnetic field action: Magnetic fields primarily regulate the emulsification process by influencing the behavior of fluids containing magnetic particles. Their core functions include: driving magnetic particles: The magnetic field causes magnetic particles to align or move within the fluid, affecting the interfacial tension of the emulsion and the droplet formation process. Controlling droplet morphology: The magnetic field can influence the stretching, aggregation, or splitting behavior of droplets, thereby optimizing droplet size and distribution uniformity. Synergistic effect with electric fields: The magnetic field affects the electric field's ability to control the fluid; appropriate magnetic field parameters can enhance or stabilize the droplet formation process.

[0061] Specific adjustment criteria: Adjusting the position of the electromagnet, and adjusting the area of ​​influence of the magnetic field in the fluid channel: A magnetic field near the inlet (dispersed phase injection area): promotes uniform distribution of magnetic particles in the dispersed phase, improving the stability of initial droplet formation. A magnetic field located in the fluid confluence area (droplet formation point): affects the droplet shearing process and can be used to control droplet size.

[0062] Placing the magnetic field near the outlet region enhances droplet interfacial stability, reduces droplet coalescence rate, and minimizes droplet morphology fluctuations during flow. Optimization methods include monitoring droplet formation dynamics using real-time microscopy and high-speed imaging systems. If droplet size is too large or widely distributed, the magnetic field gradient can be adjusted to bring the magnetic field's application point closer to the droplet shear fracture region. If interfacial coalescence occurs, the magnetic field's application area can be appropriately shifted downstream to enhance droplet stability.

[0063] The adjustment of magnetic field strength is based on: the concentration of magnetic particles in the fluid: For fluids with high concentrations of magnetic particles, a stronger magnetic field can effectively control particle distribution and prevent local aggregation that could lead to droplet instability. For fluids with low concentrations of magnetic particles, the magnetic field should be appropriately reduced to avoid excessive stretching forces on non-magnetic droplets, which could result in uneven morphology. It also depends on droplet size requirements: If the droplets are too large, the magnetic field can be appropriately strengthened to increase the droplet breakage rate due to the movement of magnetic particles. If the droplets are unstable or prone to aggregation, the magnetic field strength should be reduced to prevent excessive action by magnetic particles that could cause droplet coalescence. Optimization method: The initial magnetic field strength can be set between 10-100 mT and gradually optimized through experiments. The droplet formation effect can be observed under a microscope, and the magnetic field strength can be adjusted to optimize droplet size and stability.

[0064] The adjustment of the magnetic field direction is based on the following: The magnetic field direction affects the arrangement of magnetic particles and the droplet interface morphology: Parallel to the fluid direction (axial magnetic field): Magnetic particles align along the fluid direction, contributing to droplet stability during flow. Perpendicular to the fluid direction (transverse magnetic field): Promotes the aggregation of magnetic particles at the interface, altering droplet formation and affecting shearing. Rotating magnetic field (alternating magnetic field): Enhances the random distribution of magnetic particles, improving the uniformity and stability of the emulsion. Optimization methods: If the droplet distribution is uneven, the magnetic field direction can be adjusted to make the magnetic particles act more evenly on the droplet interface. If the droplet interface morphology is irregular or unstable, an alternating magnetic field can be used to dynamically adjust the distribution of magnetic particles.

[0065] The adjustment of the frequency of the frequency-modulated power supply is based on the following: The frequency of the magnetic field affects the response behavior of magnetic particles: Low-frequency magnetic field (1-100Hz): Suitable for larger magnetic particles, allowing them to slowly adjust their distribution along the magnetic field direction, which helps in the stable formation of droplets. Medium-frequency magnetic field (100Hz-10kHz): Suitable for most microfluidic emulsion systems, allowing dynamic control of the movement of magnetic particles during droplet formation, improving droplet uniformity. High-frequency magnetic field (>10kHz): Can be used for fine control of ultra-small or nanoparticles, but may cause hysteresis effects and is not suitable for high-viscosity fluids. Optimization method: Observe the droplet formation at different frequencies. If the droplets are too large or unevenly distributed, the magnetic field frequency can be appropriately increased. If the droplets are prone to coalescence or instability after formation, the magnetic field frequency should be decreased to allow the magnetic particles to slowly adjust, improving droplet stability.

[0066] Specific adjustment methods:

[0067] Preliminary magnetic field parameters: Location: Place the magnetic field near the droplet formation region to optimize the droplet formation process. Intensity: Set the initial magnetic field strength (e.g., 20-50 mT) based on the magnetic particle concentration and fluid characteristics. Direction: Preferably select a magnetic field parallel to the fluid direction to improve flow stability. Frequency: Start testing at 100 Hz and gradually adjust to optimize the droplet interface morphology.

[0068] Real-time monitoring and adjustment: The size and shape of the droplets are observed using a microscope system, and the strength and direction of the magnetic field are fine-tuned. If the droplet distribution is uneven, the position or direction of the magnetic field is adjusted to optimize the distribution of magnetic particles. If the droplets tend to merge or are unstable, the magnetic field strength is reduced or the frequency of the frequency-modulated power supply is decreased.

[0069] Co-optimization with electric field: If the electric field dominates the emulsification process, the magnetic field should be appropriately reduced to avoid interfering with the droplet interface morphology. If the magnetic field has a significant impact on droplet stability, the electric field parameters need to be coordinated to optimize droplet distribution in a synergistic manner.

[0070] Therefore, the present invention employs a microfluidic device and method for multi-field synergistic emulsification, which can precisely control the emulsification process in a microfluidic system through the synergistic effect of electric and magnetic fields, thereby optimizing the particle size distribution, stability, and formation rate of the emulsion.

[0071] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for a microfluidic device of multi-field synergistic emulsification, characterized in that, The device includes a chamber containing a microfluidic chip, an electric field generator, and a magnetic field generator. The chamber is connected to a high-precision injection pump via a pressure sensor, a flow sensor, an inlet valve, an intermediate container, and an injection pump valve. The chamber is also connected to a confining pressure tracking pump via a pressure sensor and a back pressure pump valve. Furthermore, the chamber is connected to a back pressure pump via a pressure sensor and a flow sensor. The back pressure pump is connected to a fluid collector. The high-precision injection pump, confining pressure tracking pump, back pressure pump, and high-resolution microscope are connected to a computer control unit. Heating wires are installed inside the chamber. The method includes the following steps: Step S1: Initialize the device and ensure a normal connection; Confirm that the microfluidic chip, electric field generator, magnetic field generator, high-precision injection pump, confining pressure tracking pump, high-resolution microscope, computer control terminal, back pressure pump, fluid collector, pressure sensor, injection pump valve, inlet valve, back pressure pump valve, outlet valve, and heating wire are properly connected. Step S2: Preparation and inflow of fluid; The raw materials required to prepare the target emulsion include a continuous phase and a dispersed phase. The liquid storage pipe in the high-precision injection pump is connected to the inlet branch of the microfluidic chip. The two inlet branches of the microfluidic chip correspond to the inlet branches of the continuous phase and the dispersed phase, respectively. Step S3: Multi-field synergistic regulation; Location: Place the magnetic field near the droplet formation area to optimize the droplet formation process; Intensity: Set the initial magnetic field strength based on the magnetic particle concentration and fluid characteristics; Direction: Select a magnetic field parallel to the fluid direction to improve flow stability; Frequency: Start testing from 100 Hz and gradually adjust to optimize the droplet interface morphology; Real-time monitoring and adjustment: Observe the droplet size and morphology using a microscope system to fine-tune the magnetic field strength and direction; If the droplet distribution is uneven, adjust the magnetic field position or direction to optimize the magnetic particle distribution; If the droplets are prone to coalescence or instability, reduce the magnetic field strength or decrease the frequency of the frequency-modulated power supply; Co-optimization with the electric field: If the electric field dominates the emulsification process, the magnetic field should be appropriately reduced to avoid interfering with the droplet interface morphology; If the magnetic field has a significant impact on droplet stability, the electric field parameters need to be coordinated to synergistically optimize the droplet distribution. Step S4: Monitoring and data acquisition of the emulsification process of the fluid; A real-time high-resolution microscope is activated to dynamically observe the droplet formation process. Image analysis is used to collect and record key data of the droplets during the emulsification process. Pressure fluctuations in the channel during the emulsification process are monitored in real time through a pressure sensor and a back pressure pump. Step S5: Collect fluid. The fluid collector was activated to guide the generated emulsion from the outlet channel to the storage container for segmented collection, and the generation conditions and parameters of each sample were recorded; the particle size distribution and long-term stability of the emulsion samples were measured using a particle size analyzer and dynamic light scattering (DLS) technology. Step S6: Equipment cleaning and maintenance; Shut down all devices and drain any remaining liquid from the fluid channels; clean the microfluidic chip, high-precision injection pump, and fluid channels with a cleaning solvent to avoid cross-contamination; check the operating status of the electric and magnetic field devices, and after ensuring there are no abnormalities, turn off the system power to complete the operation steps; the magnetic field will affect the electric field's ability to control the fluid.

2. The method of a microfluidic device for multi-field synergistic emulsification according to claim 1, characterized in that, The microfluidic chip has two inlet branches and one outlet branch.

3. The method of a microfluidic device for multi-field synergistic emulsification according to claim 1, characterized in that, The electric field generating device includes electrodes and a first frequency-modulated power supply. The electrodes are located on both sides of the fluid channel inside the chamber, and the first frequency-modulated power supply is connected to the electrodes.

4. The method of a microfluidic device for multi-field synergistic emulsification according to claim 1, characterized in that, The magnetic field generating device includes a slide rail, an electromagnet, and a second frequency-modulated power supply. The electromagnet is mounted on the slide rail.

5. The method of a microfluidic device for multi-field synergistic emulsification according to claim 1, characterized in that, In step S1, the heating wire is adjusted to set the microfluidic chip temperature to the target value; the pressure sensor and back pressure pump are started to perform calibration.

6. The method of a microfluidic device for multi-field synergistic emulsification according to claim 1, characterized in that, In step S2, the flow rate and flow parameters of the high-precision injection pump are set, and the high-precision injection pump is started to accurately deliver the continuous phase and dispersed phase to the microfluidic chip.

7. The method of a microfluidic device for multi-field synergistic emulsification according to claim 1, characterized in that, In step S3, the electric field generating device is activated by adjusting the electrode position, intensity, and frequency; the magnetic field generating device is activated by using a slide rail to precisely position the electromagnet and adjusting the second frequency-modulated power supply.

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