Particle sorting microdevice, system, and method based on periodic wave design

Abstract

The present application relates to the technical field of micro-nanoparticle separation, and in particular to a particle sorting micro device, system and method based on a periodic wave design. The present application provides a particle sorting micro device based on a periodic wave design, comprising: a substrate, a first excitation electrode, a second excitation electrode, a cover, and a bipolar electrode. The particle sorting micro device designed by the present application is different from the traditional direct current channel, and a special-shaped micro channel structure is designed, and the periodic wave is used to achieve the pre-focusing effect on mixed particles. The present application realizes the separation of particles in the micro channel by applying excitation signals to the two excitation electrodes. The present application solves the problems of complex operation, high cost and low integration degree of the existing particle separation device using a single dielectrophoresis principle.

Description

Technical Field

[0001] This invention relates to the field of micro-nano particle separation technology, and particularly to: 1. a particle sorting microdevice based on a periodic wave-shaped design; 2. a particle sorting system to be built based on the particle sorting microdevice; and 3. a method of using the particle sorting system. Background Technology

[0002] Micro- and nano-particle separation is a necessary process before performing a series of operations such as water quality analysis, nanoscale exosome separation, and early cancer diagnosis.

[0003] Many effective separation methods have been developed, such as: operation methods based on external properties (fluorescence-activated cell sorting, magnetic-activated cell sorting, separation based on surface affinity) and operation methods based on intrinsic physical properties (electrical sorting, optical sorting, acoustic sorting, magnetic sorting, microporous filtration, inertial force separation).

[0004] Among these methods, particle separation using the single dielectrophoresis principle has achieved good results. Dielectrophoresis refers to the phenomenon where particles, after being polarized in a non-uniform electric field, form electric dipoles. Under the influence of the electric field, these dipoles move towards regions with larger or smaller electric field gradients, depending on the sign of the real part of the Clausius-Mosotti factor. Separation can be achieved by adjusting the frequency of the driving voltage to change the sign of the particles relative to the real part of the Clausius-Mosotti factor, thus causing different particles to move in different directions. However, existing particle separation devices using the single dielectrophoresis principle cannot guarantee that all particles enter the effective dielectrophoresis range. This often requires the fabrication of special flow channels or the use of sheath flow for particle pre-focusing, necessitating the introduction of complex external fluid control equipment. This not only increases operational complexity and equipment cost but also makes equipment integration difficult. Summary of the Invention

[0005] Therefore, it is necessary to address the problems of complex operation, high cost, and low integration of existing particle separation devices that utilize a single dielectrophoresis principle, and to provide particle sorting microdevices, systems, and methods based on periodic wave-shaped design.

[0006] This invention is achieved using the following technical solution:

[0007] In a first aspect, the present invention provides a particle sorting microdevice based on a periodic wave-shaped design, comprising: a substrate, a first excitation electrode, a second excitation electrode, a cover plate, and a bipolar electrode.

[0008] The first excitation electrode and the second excitation electrode are disposed on the substrate with a predetermined interval between them. The predetermined interval includes: a periodic wavy interval of the main body, and a straight interval extending from one end of the periodic wavy interval.

[0009] A cover plate is disposed on the substrate and presses down on the first and second excitation electrodes. The cover plate has microchannels corresponding to the shape of a preset interval; the width of the microchannels is greater than or equal to the width of the preset interval. The microchannels are used to flow the mixed particle solution. One end of the microchannel corresponding to the linear interval serves as a separation port and is connected to three branching channels; the other end of the microchannel has a liquid inlet. The three branching channels include: a first branching channel, a second branching channel, and a third branching channel.

[0010] A bipolar electrode is disposed on the substrate and located within the microchannel. The bipolar electrode corresponds to the shape of the microchannel; the width of the bipolar electrode is smaller than the width of a preset interval. Region 1 is formed between the bipolar electrode and the first excitation electrode, Region 2 is formed between the bipolar electrode and the second excitation electrode, and Region 3 is formed between the bipolar electrode and the second excitation electrode. The outlet of Region 1 faces the first bifurcation channel, the outlet of Region 2 faces the second bifurcation channel, and the outlet of Region 3 faces the third bifurcation channel.

[0011] In this process, excitation signals are applied to the first excitation electrode and the second excitation electrode, and in conjunction with the bipolar electrode, the mixed particle solution that enters the microchannel from the liquid inlet is gradually separated into three particle bundles as it flows toward the separation port. These bundles are located in Region 1, Region 2, and Region 3, respectively, and finally flow to the three branch channels to achieve particle sorting.

[0012] This particle sorting microdevice, based on a periodic wave-shaped design, implements the method or process according to embodiments of this disclosure.

[0013] In a second aspect, the present invention provides a particle sorting system comprising: a particle sorting microdevice based on a periodic wave-shaped design as disclosed in the first aspect, a solution driver, a signal generator, an imager, and a host computer.

[0014] A solution driver is used to introduce the mixed particle solution through the inlet and to cause the mixed particle solution to flow towards the separation port. A signal generator is used to adjust and apply excitation signals to the first and second excitation electrodes. An imager is used to capture images of the particle distribution of the mixed particle solution. A host computer is used to receive and process the particle distribution images to determine the degree of particle separation.

[0015] This particle sorting system implements the methods or processes according to embodiments of this disclosure.

[0016] Thirdly, the present invention discloses a method of using the particle sorting system of the second aspect, comprising the following steps:

[0017] Step 1: The mixed particle solution is introduced into the microchannel through the inlet using a solution actuator, and the mixed particle solution is driven to flow towards the separation port. At the same time, excitation signals are applied to the first excitation electrode and the second excitation electrode. With the help of bipolar electrodes, the mixed particle solution is gradually separated into three particle beams as it flows towards the separation port, and they are respectively located in region 1, region 2 and region 3. Finally, they flow into three bifurcation channels to achieve particle sorting.

[0018] Step two involves recovering particles at the exits of the three branch channels and determining the degree of particle separation.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1) The particle sorting microdevice designed in this invention can simultaneously achieve particle focusing and separation with a simplified structure, and has a high degree of integration and is easy to operate.

[0021] 2) The particle sorting microdevice designed in this invention is different from the traditional DC channel. It has a specially shaped microchannel structure and uses a periodic wave-shaped channel to achieve the effect of pre-focusing particles.

[0022] 3) This invention achieves particle pre-focusing and separation in a microchannel by applying an excitation signal with superimposed high and low frequency electrical signals to two excitation electrodes.

[0023] 4) The particle sorting micro-device designed in this invention utilizes the unique concave-convex arc shape of the two excitation electrodes and the central floating electrode (i.e., bipolar electrode) located between them. Compared with the symmetrical rectangular electrode, it effectively increases the ICEO eddy and dielectric electrophoresis power in the electric field, thereby achieving high-efficiency focusing and separation. Attached Figure Description

[0024] Figure 1 This is a structural diagram of the particle sorting microdevice based on a periodic wave-shaped design according to Embodiment 1 of the present invention;

[0025] Figure 2 for Figure 1 Top view of a micro-device for sorting particles;

[0026] Figure 3 for Figure 1 A schematic diagram of the particle sorting effect of a medium particle sorting microdevice;

[0027] Figure 4 for Figure 1 Velocity distribution diagram of focusing effect in microchannels;

[0028] Figure 5 for Figure 1 Particle distribution trajectory diagram of microchannels;

[0029] Figure 6 for Figure 1 Simulation diagram of the electric field in the microchannel region;

[0030] Figure 7 for Figure 6 Distribution of dielectric force direction on the longitudinal section of the electric field in the middle region;

[0031] Figure 8 for Figure 2 Waveform of the excitation signal applied in the middle;

[0032] Figure 9 for Figure 1 The fabrication process of particle sorting microdevices;

[0033] Figure 10 This is a structural diagram of the particle sorting system in Embodiment 2 of the present invention;

[0034] Figure 11 for Figure 9 A flowchart illustrating the usage of a particle sorting system;

[0035] Figure 12 This is a frequency response characteristic curve of yeast cells and polystyrene microspheres in Example 3 of the present invention;

[0036] Figure 13 The experimental results are from Example 3 of this invention. Figure 1 ;

[0037] Figure 14 The experimental results are from Example 3 of this invention. Figure 2 ;

[0038] Figure 15 The experimental results are from Example 3 of this invention. Figure 3 ;

[0039] The attached diagram lists the components represented by each number as follows:

[0040] 1. First excitation electrode; 2. Second excitation electrode; 3. Bipolar electrode; 4. Liquid inlet; 5. Microchannel; 6. First branch channel; 7. Second branch channel; 8. Third branch channel. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] It should be noted that when a component is said to be "installed on" another component, it can be directly on the other component or it may be in a component that is centered on it. When a component is said to be "set on" another component, it can be directly set on the other component or it may also be in a component that is centered on it. When a component is said to be "fixed to" another component, it can be directly fixed to the other component or it may also be in a component that is centered on it.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.

[0044] Example 1

[0045] Please see Figure 1 , Figure 1 The diagram shows the structure of the particle sorting microdevice based on a periodic wave-shaped design provided in Example 1.

[0046] like Figure 1 As shown, the particle sorting microdevice based on the periodic wave-shaped design includes: a substrate, a first excitation electrode 1, a second excitation electrode 2, a cover plate, and a bipolar electrode 3.

[0047] The substrate serves as the foundation of the entire particle sorting microdevice. Typically, the substrate material is glass, such as a glass sheet. Of course, other rigid materials can also be used, such as acrylic, silicon, glass-modified silicon, and polycarbonate (PC).

[0048] A first excitation electrode 1 and a second excitation electrode 2 are disposed on the substrate with a predetermined interval between them. The first excitation electrode 1 and the second excitation electrode 2 can be ITO electrodes or metal electrodes. The predetermined interval includes: a periodic wavy interval of the main body, and a straight interval extending from one end of the periodic wavy interval (referred to as straight interval one). See [reference needed] Figure 1 Alternatively, a straight interval can be extended from the other end of the periodic wave-shaped interval (referred to as straight interval two).

[0049] It should be noted that, in Figure 1 The particle sorting micro-devices at the top shorten the number of cycles in the periodic wave-shaped interval; in Figure 1 The lower part increases the number of cycles in the wavy interval; both actually express the same meaning—the main body of the preset interval is wavy and multi-cycle.

[0050] A cover plate is placed on the substrate and presses down on the first excitation electrode 1 and the second excitation electrode 2. Typically, a PDMS plate is used as the cover plate. However, other polymer materials can also be used, such as polymethyl methacrylate (PMMA), silicone, etc. Microchannels 5, corresponding to the shape of a preset interval, are machined on the cover plate. It should be noted that the width of the microchannels 5 is greater than or equal to the width of the preset interval. That is, along the vertical direction of the substrate, the microchannels 5 can cover the entire preset interval, and may even cover part of the first excitation electrode 1 and the second excitation electrode 2.

[0051] Microchannel 5 is used to flow mixed particulate solution. One end of microchannel 5 corresponding to the linear interval (i.e., linear interval one) serves as a separation port and is connected to three branch channels. The other end of microchannel 5 is provided with liquid inlet 4; the three branch channels include: first branch channel 6, second branch channel 7, and third branch channel 8.

[0052] The bipolar electrode 3 is disposed on the substrate and located within the microchannel 5. The bipolar electrode 3 corresponds in shape to the microchannel 5—see [reference needed]. Figure 1 The main body of the bipolar electrode 3 is also periodically wavy. The width of the bipolar electrode 3 is smaller than the width of the preset interval. Thus, region one is formed between the bipolar electrode 3 and the first excitation electrode 1, region two is formed between the bipolar electrode 3 and the second excitation electrode 2, and region three is formed between the bipolar electrode 3 and the second excitation electrode 2. The outlet of region one faces the first bifurcation channel 6, the outlet of region two faces the second bifurcation channel 7, and the outlet of region three faces the third bifurcation channel 8.

[0053] In this design, regions one and three have the same width, allowing for a symmetrical distribution of the electric field generated at the edge of the bipolar electrode 3. The width of the bipolar electrode 3 is adjusted according to the specific particle type of the mixed particle solution: this is because a wider bipolar electrode 3 results in a greater number of focused particles; however, if the width of the bipolar electrode 3 is too wide, too many particles will focus onto it, affecting the high-frequency signal's particle sorting effect. Therefore, the width must be adjusted accordingly based on the specific particle type.

[0054] In summary, see Figure 2 When this particle sorting micro-device is in use, an excitation signal is applied to the first excitation electrode 1 and the second excitation electrode 2, and in conjunction with the bipolar electrode 3, the mixed particle solution that enters the microfluidic channel 5 from the liquid inlet 4 is gradually separated into three particle bundles as it flows toward the separation port, and they are respectively located in region one, region two and region three, and finally flow to the three branch channels to achieve particle sorting.

[0055] It is important to note that:

[0056] The excitation signal can be a high-frequency signal or a high- or low-frequency modulated electrical signal.

[0057] S1, the high-frequency signal generates positive and negative permittivity in microchannel 5, causing different particles to deflect to different degrees and directions, thus achieving particle separation. Particles subjected to positive permittivity are separated into regions one and three, while particles subjected to negative permittivity are separated into region two. Therefore, the particle beams located in the first bifurcation channel 6 and the third bifurcation channel 8 contain the same particles, but are different from the particles in the particle beam located in the second bifurcation channel 7, such as... Figure 3 As shown.

[0058] The expression for the high-frequency signal is: A 2 sin ( w 2 t );

[0059] In the formula, A 2 represents the voltage amplitude of the high-frequency signal. w 2 indicates the frequency of the high-frequency signal. w 2≥500kHz, t Indicates time.

[0060] Specifically, this invention combines induced charge electroosmosis vortex technology and wave-shaped flow channel geometry to achieve particle focusing, and utilizes particle dielectrophoresis properties to achieve the separation of different particles.

[0061] Induced charge electroosmosis vortices refer to the presence of vortex flows at the edge of the bipolar electrode 3, which are induced around an electrode carrying an opposite charge. This phenomenon is caused by the interaction of mobile ions within the induced bilayer (IDL) on a polarizable surface with the tangential electric field component. Under this induced charge electroosmosis, the sample can be transported to the center of the bipolar electrode 3. Specifically, a pair of counter-rotating vortices are formed around the bipolar electrode 3. These vortices interact to form a flow stagnation line (FSL), and particles subsequently aggregate in the flow around the FSL, thus focusing the particles into a particle beam. The width and number of particle beams can be adjusted by changing the width of the bipolar electrode 3.

[0062] In this invention, the main body of the microchannel 5 is wave-shaped, designed to enhance the focusing effect using geometric properties. (See attached image) Figure 4 This demonstrates the velocity distribution of the focusing effect of microchannel 5 itself without any applied electrical signal. Figure 4 It can be seen that the velocity is greatest above the bipolar electrode 3 (i.e., region two), which can achieve a better focusing effect on particles.

[0063] See Figure 5 This demonstrates the simulation results of particle distribution without any applied electrical signal. Figure 5It can be seen that along the flow direction of the mixed particle solution, the particles are randomly distributed at the beginning and then gradually focus near the bipolar electrode 3.

[0064] Based on the above microchannel design, this invention utilizes dielectric force to achieve particle separation: when a high-frequency signal is applied to the excitation electrode, an uneven electric field with concave and convex arcs is generated, which can generate the electric field gradient required for dielectric force; and different particles have different degrees of polarization and are subjected to dielectric force in different directions, thus their migration direction and speed will be different. This characteristic can be used to achieve separation effect.

[0065] See Figure 6 This displays a simulation of the electric field within the microchannel. Figure 6 It can be seen that there is a large electric field gradient near the bend of the bipolar electrode 3, while the bipolar electrode 3 itself is an equipotential body with no change in electric field.

[0066] See Figure 7 The diagram shows the distribution of the dielectric force direction on the longitudinal section of the regional electric field. It can be seen that within a certain frequency range, particles subjected to positive dielectric force will move towards the edge of the bipolar electrode 3, while particles subjected to negative dielectric force will gather towards the surface center of the bipolar electrode 3, thereby achieving the purpose of separating different particles.

[0067] This is because when a particle has a greater polarization ability than the solution it is in, the direction of the dipole induced by the non-uniform electric field will automatically adjust to be parallel to the electric field and have the same orientation. This will cause the particle to be subjected to a positive permittivity, so the particle will deflect and focus towards the edge of the bipolar electrode 3 where the electric field strength is high. Conversely, when a particle has a smaller polarization ability than the solution it is in, the direction of the dipole induced by the non-uniform electric field will still automatically adjust to be parallel to the electric field and have the opposite orientation. This will cause the particle to be subjected to a negative permittivity, so the particle will deflect towards the middle of the bipolar electrode 3 where the electric field strength is low.

[0068] Alternatively, the direction of the force on the particle can be explained mathematically: according to the dielectrophoretic force formula, the direction of the dielectrophoretic force on the particle is determined by the Clausius-Mosotti factor (…). K CM The real part of the Clausius-Mosotti factor determines the sign of the factor, which is related to the dielectric constant of the particle and the frequency of the applied high-frequency signal. Normally, the dielectric constant of a particle does not change in solution, so by adjusting the frequency of the high-frequency signal, a suitable range is found where the real parts of the Clausius-Mosotti factor for different particles have opposite signs, thus subjecting different particles to dielectric forces in different directions.

[0069] S2, the high-frequency and low-frequency modulated electrical signals, are the modulated signals generated by the superposition of high-frequency and low-frequency signals. The function of the high-frequency signal is explained above. The low-frequency signal induces the formation of the double layer on the central floating electrode, generating an induced current electroosmotic vortex to achieve particle pre-focusing.

[0070] See Figure 8 The expressions for high-frequency and low-frequency modulated electrical signals are: A 1 sin ( w 1 t )+ A 2 sin ( w 2 t );

[0071] In the formula, A 1 indicates the voltage amplitude of the low-frequency signal. w 1 indicates the frequency of the low-frequency signal. w 1≤1kHz; A 2 represents the voltage amplitude of the high-frequency signal. w 2 indicates the frequency of the high-frequency signal. w 2≥500kHz, t Indicates time.

[0072] Referring to the description of S1, although particle focusing can be achieved solely through the wavy flow channel, applying a low-frequency signal can superimpose the focusing effect, thereby enhancing it.

[0073] The excitation signal is obtained by superimposing low-frequency and high-frequency signals. After the excitation signal is applied to the excitation electrode, the low-frequency signal induces the formation of the double layer of the bipolar electrode 3, generating an induced current electroosmotic vortex to achieve particle focusing; while the high-frequency signal generates a dielectric force in the microchannel 5, causing different particles to deflect to different degrees and in different directions, thereby achieving particle separation.

[0074] This embodiment 1 also discloses the fabrication process of the above-mentioned particle sorting microdevice, such as... Figure 9 As shown:

[0075] On the one hand, photolithography is used to form microchannel molds on glass or silicon wafers; on the other hand, PDMS boards are used to create microchannel molds; finally, the molds are demolded and holes are punched.

[0076] On the other hand, soft lithography is used to pattern the photoresist (such as BN303 negative photoresist), and then wet etching or dry etching is used to etch the ITO plate to complete the fabrication of two excitation electrodes and bipolar electrodes 3. After both aspects are completed, plasma surface treatment can be used to perform irreversible bonding to form a particle sorting microdevice.

[0077] Of course, to facilitate the application of excitation signals, the two excitation electrodes can be led out with wires (electrically connected using conductive tape, conductive silver paste, etc.).

[0078] Example 2

[0079] This embodiment 2 discloses a particle sorting system, which is constructed based on the particle sorting microdevice based on the periodic wave-shaped design disclosed in embodiment 1.

[0080] See Figure 10 The particle sorting system includes: particle sorting microdevices, solution driver, signal generator, imager, and host computer.

[0081] The particle sorting microdevice is the one based on a periodic wave-shaped design disclosed in Example 1. A solution actuator is used to introduce the mixed particle solution from the inlet 4 and to cause the mixed particle solution to flow towards the separation port. Commonly used solution actuators are microfluidic pumps or peristaltic actuators: the microfluidic pump pushes at the inlet 4 and / or draws liquid at the outlets of the three bifurcated channels, thereby driving the mixed particle solution to flow within the microchannels 5. Of course, other devices utilizing pressure or capillary effects can also be used to control the flow of the mixed particle solution.

[0082] A signal generator is used to adjust and apply excitation signals to the first excitation electrode 1 and the second excitation electrode 2. An image capture device is used to capture particle distribution images of the mixed particle solution. A host computer is used to receive and process the particle distribution images to determine the degree of particle separation.

[0083] See Figure 11 This embodiment 2 also discloses a method for using the particle sorting system, including the following steps:

[0084] Step 1: The mixed particle solution is introduced into the microchannel 5 through the inlet 4 using a solution actuator, and the mixed particle solution is driven to flow towards the separation port. At the same time, excitation signals are applied to the first excitation electrode 1 and the second excitation electrode 2. With the help of the bipolar electrode 3, the mixed particle solution is gradually separated into 3 particle bundles as it flows towards the separation port, and they are respectively located in region 1, region 2 and region 3. Finally, they flow to the 3 branching channels to achieve particle sorting.

[0085] Step one involves the feeding, focusing, and separation of particles, which is the core of this particle sorting system.

[0086] Step two involves recovering particles at the exits of the three branch channels and determining the degree of particle separation.

[0087] In step two, the particle distribution images at the exits of the three bifurcated channels are captured by an imager. Based on the size, shape, color and other characteristics of the particles, the particles in the images are marked and distinguished to quantify the degree of separation.

[0088] Example 3

[0089] This embodiment 3 discloses an application example of the particle sorting system of embodiment 2 to illustrate and verify its function.

[0090] In this example 3, three solutions were prepared:

[0091] 1. Place yeast cells in deionized water to prepare the first particle solution;

[0092] 2. Place 9 μm polystyrene (PS) microspheres in deionized water to prepare a second particle solution;

[0093] 3. Place yeast cells and 9 μm polystyrene (PS) microspheres in deionized water to prepare a mixed particle solution.

[0094] See Figure 12 The frequency response characteristics of yeast cells and 9 μm polystyrene (PS) spheres in deionized water are shown. Specifically, the 9 μm polystyrene (PS) spheres exhibit frequency response characteristics at 10... 3 ~10 8 Hz frequency range K CM The real part is negative, meaning it is subject to negative dielectric force; while yeast cells are approximately 10 3 ~6×10 7 Hz range K CM The real part is positive, meaning it is subject to the normal mesophoretic force. Therefore, in 10 3 ~6×10 7 The separation of these two particles can be achieved within a frequency range of Hz.

[0095] Therefore, the above three solutions were processed according to the method of Example 2 (using a high-frequency signal as the excitation signal), and the results are shown below. Figures 13-15 .in, A 2. Take 10V. w 2. Set the frequency to 510kHz.

[0096] in, Figure 13 The changes in deionized water containing only yeast cells before and after 10 seconds are shown under the influence of an excitation signal. It can be seen that as time progresses, the yeast cells gradually aggregate in regions one and three, which have larger electric field gradients.

[0097] Figure 14The results show the changes in deionized water containing only polystyrene (PS) microspheres over 10 seconds under the influence of an excitation signal. It can be seen that as time progresses, the polystyrene (PS) microspheres gradually aggregate in region two.

[0098] Figure 15 This demonstrates the changes in yeast cells and polystyrene (PS) spheres in a mixed particulate solution before and after 10 seconds under the influence of an excitation signal. It can be seen that... Figure 13 , Figure 14 The results for a single particle are consistent with the verification, and the two particles can be clearly separated, which also demonstrates the feasibility of the device.

[0099] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0100] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A particle sorting microdevice based on a periodic wave-shaped design, comprising: Base; The first excitation electrode and the second excitation electrode are disposed on the substrate with a preset interval between them; The preset interval includes: the periodic wavy interval of the main body, and a straight interval extending from one end of the periodic wavy interval. A cover plate is disposed on a substrate and presses down on the first and second excitation electrodes; the cover plate is provided with microchannels corresponding to a preset interval shape; the width of the microchannels is greater than or equal to the width of the preset interval; the microchannels are used to flow a mixed particle solution; wherein, one end of the microchannel corresponding to the linear interval serves as a separation port and is connected to three branch channels; the other end of the microchannel is provided with a liquid inlet; the three branch channels include: a first branch channel, a second branch channel, and a third branch channel; as well as A bipolar electrode is disposed on a substrate and located within a microchannel; the bipolar electrode corresponds to the shape of the microchannel; the width of the bipolar electrode is less than the width of a preset interval; a region one is formed between the bipolar electrode and the first excitation electrode, a region two is formed between the bipolar electrode and the second excitation electrode, and a region three is formed between the bipolar electrode and the second excitation electrode; the outlet of region one faces the first bifurcation channel, the outlet of region two faces the second bifurcation channel, and the outlet of region three faces the third bifurcation channel; Specifically, an excitation signal is applied to the first excitation electrode and the second excitation electrode, and in conjunction with the bipolar electrode, the mixed particle solution that enters the microchannel from the liquid inlet is gradually separated into three particle bundles as it flows toward the separation port, and they are respectively located in region one, region two and region three, and finally flow to three branch channels to achieve particle sorting. The excitation signal is a modulation signal generated by superimposing high-frequency and low-frequency signals. The high-frequency signal is used to generate positive and negative dielectric forces in the microchannel, causing different particles to deflect to different degrees and in different directions, thereby achieving particle separation. The low-frequency signal is used to induce the formation of the double layer of the bipolar electrode, generating an induced current electroosmotic vortex to achieve particle pre-focusing.

2. The particle sorting microdevice based on a periodic wave-shaped design according to claim 1, characterized in that, The substrate is made of a rigid material; the cover is made of a polymer material.

3. The particle sorting microdevice based on a periodic wave-shaped design according to claim 1, characterized in that, The expressions for the excitation signal and the low-frequency modulation signal are as follows: A 1 sin ( w 1 t )+ A 2 sin ( w 2 t ); In the formula, A 1 indicates the voltage amplitude of the low-frequency signal. w 1 indicates the frequency of the low-frequency signal. w 1≤1kHz; A 2 represents the voltage amplitude of the high-frequency signal. w 2 indicates the frequency of the high-frequency signal. w 2≥500kHz, t Indicates time.

4. The particle sorting microdevice based on a periodic wave-shaped design according to claim 1, characterized in that, Region 1 and Region 3 have the same width.

5. The particle sorting microdevice based on a periodic wave-shaped design according to claim 1, characterized in that, The width of the bipolar electrode is adjusted according to the specific particle type of the mixed particle solution.

6. The particle sorting microdevice based on a periodic wave-shaped design according to claim 1, characterized in that, The particles in the particle beams located in the first and third bifurcation channels are the same, but different from the particles in the particle beam located in the second bifurcation channel.

7. A particle sorting system, characterized in that, include: Particle sorting microdevice based on periodic wave-shaped design as described in any one of claims 1-6; A solution actuator is used to introduce a mixed particle solution from the inlet and drive the mixed particle solution to flow toward the separation port; A signal generator is used to adjust and apply excitation signals to the first excitation electrode and the second excitation electrode; Image capture unit, used to capture images of the particle distribution in a mixed particulate solution; as well as The host computer is used to receive and process particle distribution images to determine the degree of particle separation.

8. The particle sorting system according to claim 7, characterized in that, The solution driver is a microfluidic pump or a peristaltic actuator.

9. The method of using the particle sorting system according to claim 7 or 8, characterized in that, Includes the following steps: Step 1: The mixed particle solution is introduced into the microchannel through the inlet using a solution actuator, and the mixed particle solution is driven to flow towards the separation port. At the same time, excitation signals are applied to the first excitation electrode and the second excitation electrode. With the help of bipolar electrodes, the mixed particle solution is gradually separated into three particle beams as it flows towards the separation port, and they are respectively located in region 1, region 2 and region 3. Finally, they flow into three bifurcation channels to achieve particle sorting. Step two involves recovering particles at the exits of the three branch channels and determining the degree of particle separation.

Images