An apparatus for directional control and separation of charged particles in an electrolyte

Abstract

The application discloses a device for direction control and separation of charged particles in electrolyte, which comprises: a microfluidic channel, the microfluidic channel has a sample inlet port and a sample outlet port, a fluid flows from the sample inlet port to the sample outlet port at a speed v0, a separation chamber is formed inside the microfluidic channel, the fluid contains charged particles, and the charged particles are separated inside the separation chamber; two or more groups of electrodes, the number of electrodes in each group is the same or different, each electrode is in contact with the fluid and forms a pseudo-capacitance and / or a double-layer capacitance on the interface where the electrode is in contact with the fluid, the electrodes are arranged in parallel inside the microfluidic channel and can have a certain angle between the arrangement direction and the flow direction of the fluid; a plurality of conductor leads; and two or more driving power sources, each driving power source is connected with one group of electrodes, the driving power source generates a periodic voltage or current excitation, and the voltage excitation or the current excitation output by the driving power source in one output period is in a change state.

Description

Technical Field

[0001] This invention relates to the field of charged particle motion control, and more specifically, to a device for directional control and separation of charged particles in an electrolyte. Background Technology

[0002] Charged particles in liquids or colloids will move under the influence of an electric field. By introducing an electric current into a liquid or colloidal electrolyte to create an electric field, the fluid or the charged particles in the fluid can be manipulated and controlled.

[0003] Currently, the main methods for introducing current into fluids utilize conductive electrodes, such as graphite electrodes, alloy electrodes, or certain solid metals like gold and platinum. The electrodes are typically placed perpendicular to the direction of fluid movement, and different charged particles are separated by controlling the displacement differences of charged particles in the electric field direction. A membrane-like structure is used between the electrode area and the separation chamber to increase fluid resistance and prevent fluid, especially microparticles, from flowing into the electrode chamber. However, in microfluidic chips, the application of this membrane-like structure results in significant voltage loss and low voltage efficiency. Simultaneously, excessively high operating voltages can induce Joule heating, affecting the uniformity of the electric field, the stability of the electrolyte solution, and the movement of charged particles. Furthermore, during the operation of the conductive electrode, the charge carriers in the electrolyte solution are ions, while those in the conductor are electrons. Therefore, at the electrode-fluid interface, due to charge carrier transfer, an unavoidable electrochemical reaction occurs. The bubbles generated by this electrochemical reaction cannot be eliminated during electrode operation, and localized bubbles are a significant cause of failure in many microfluidic chips.

[0004] Figure 1 This is a schematic diagram of a traditional free-flow electrophoresis apparatus. 301 represents charged particles in the microfluidic stream, which may be solids, gases, or liquids, including cells, bacteria, microorganisms, proteins, and vesicles. 302 is a conventional conductive electrode. 303 is a membrane-like material or microstructure used to isolate the solutions in separation chamber 305 and electrode chamber 306, ensuring a stable electric field in separation chamber 305. 304 is the outer wall of the microfluidic channel, in which the fluid moves at a velocity of v. The electric field is perpendicular to the direction of fluid movement. When the fluid flows through separation chamber 305, the charged particles in the fluid have different velocities in the electric field due to differences in their charge, mass, and other properties, resulting in differences in their deflection and thus separating different types of charged particles. When a conventional electrode is connected to an electrical signal, an electrolytic reaction occurs at the electrode interface, generating bubbles. This leads to low stability of the electrophoresis system, and due to the presence of the membrane-like structure, the actual electric field strength applied to separation chamber 305 is small, resulting in low voltage efficiency.

[0005] In US Patent 6890409, a method is employed to separate the electrode portion from the microfluidic channel to prevent air bubbles from entering the microfluidic. This approach uses additional channels to separate air bubbles generated by the electrode from the microfluidic channel, making it unsuitable for use in closed fluid channels.

[0006] Chinese patent CN200455328C discloses a method for electroporating cell walls using a pulsed electric field provided by a waveform generator. This method utilizes the electric field between multiple parallel electrodes to electroporate the cell walls. By exciting the cells with reciprocating current between the electrodes, an alternating electric field is generated to weaken the electrochemical reactions at the electrode-fluid interface. However, this approach cannot avoid the carrier conversion process, i.e., the electrolysis reaction, between the electrode and electrolyte, thus greatly limiting its application scope and effectiveness.

[0007] Chinese patent CN108885189A discloses a device for separating and analyzing samples via microfluidic electrophoresis. This patent places electrodes in electrolyte channels on both sides, and arranges an array of conductive channels between the electrolyte channels and the separation channels. These channels provide a uniform electric field distribution while generating high hydrodynamic resistance. The products of the electrolysis reaction flow out through the electrolyte channels containing the electrodes. However, this design results in an excessively large distance between the electrodes and the separation channels, leading to a low voltage required for actual separation and low voltage efficiency.

[0008] Chinese patent CN1181337C discloses a method for controlling and transporting charged particles using a traveling wave electric field. This method utilizes a linear array of parallel electrodes, applying electrical signals with a certain phase difference to each electrode to generate traveling wave signals above the electrodes. The direction of the traveling wave signals controls the forward and backward movement of two types of charged particles, thereby separating them. However, this method has extremely low separation efficiency, and the bubble problem caused by the electrolysis reaction at the electrode-electrolyte interface cannot be solved, making it difficult to apply in practice.

[0009] In summary, the core shortcomings of the existing solutions are as follows:

[0010] 1. Conventional electrodes suffer from electrolytic reactions at the electrode interface, leading to various disadvantages and severely limiting their application in microfluidic systems. For example, driving conventional electrodes with high-frequency traveling waves is a temporary solution with limited application scenarios, making widespread adoption difficult.

[0011] 2. The common electrode placement method is to use a fixed electrode device with the electric field perpendicular to the direction of fluid movement. The spacing between the electrodes is large, and the membrane-like structure between the electrodes and the separation chamber causes a certain voltage loss. The actual voltage used for separation is low, resulting in extremely low voltage efficiency of the electric field, low separation efficiency, and severely limited application scenarios.

[0012] 3. In free-flowing regions, electrophoresis is performed using dual electrodes to provide a fixed electric field. High voltage can cause problems such as Joule heating, resulting in low separation efficiency and making it unsuitable for large-scale applications. Summary of the Invention

[0013] This invention provides a device for directional control and separation of charged particles in an electrolyte, thereby solving the technical problems existing in the prior art.

[0014] To achieve the above objectives, the present invention provides an apparatus for directional control and separation of charged particles in an electrolyte, comprising:

[0015] A microfluidic channel has multiple ports, including one or more inlet ports and one or more outlet ports, through which fluid flows from the inlet port to the outlet port at a velocity v0. A separation chamber is formed inside the microfluidic channel, and the fluid contains charged particles, which are separated inside the separation chamber.

[0016] Two or more sets of electrodes, each set having the same or different number of electrodes, each electrode being in contact with the fluid and forming pseudocapacitance and / or double-layer capacitance at the interface between the electrode and the fluid, the electrodes being arranged in parallel inside the microfluidic channel and having a certain angle between the arrangement direction and the flow direction of the fluid.

[0017] Multiple conductor leads; and

[0018] Two or more driving power supplies, each driving power supply is connected to one set of electrodes, the driving power supply generates periodic voltage or current excitation, and the voltage or current excitation output by the driving power supply changes within one output cycle.

[0019] Each electrode continuously alternates between charging and discharging, forming a traveling wave electric field with periodically varying amplitude within the microfluidic channel. The electric force experienced by charged particles in this traveling wave electric field is decomposed into two mutually perpendicular components: the first component is parallel to the direction of fluid motion and drives the charged particles to move along this direction; the second component is perpendicular to the direction of fluid motion and separates the charged particles according to different charge-to-mass ratios. The expression for the traveling wave electric field E is:

[0020]

[0021] Where A is the maximum amplitude of the traveling wave electric field, T0 is the period of the traveling wave electric field, θ is the angle between the parallel electrode and the fluid flow direction, c is the phase of the traveling wave electric field, the origin is the lower left corner of the first electrode on the left, the x-axis is the fluid flow direction, the y-axis is the direction rotated 90 degrees counterclockwise from the x-axis, x and y are the abscissa and ordinate of the midpoint of the traveling wave electric field, respectively, and S0 is the period of the electric field intensity relative to the coordinate (x, y).

[0022] The traveling wave electric field E moves at a preset traveling wave speed.

[0023] In one embodiment of the present invention, the charged particles are solids, gases, liquids, or bubbles, including cells, bacteria, microorganisms, proteins, vesicles, and / or

[0024] Charged particles carry either a positive or a negative charge.

[0025] In one embodiment of the present invention, the period, frequency, and output voltage and / or current waveform of the driving power supply are all adjustable.

[0026] The amplitude, positive-to-negative amplitude ratio, and traveling speed of the traveling wave electric field are all adjustable.

[0027] In one embodiment of the present invention, during one or more cycles of the traveling wave electric field, the total input current on each electrode is equal to the total output current, that is, the net input current and net output current on each electrode are both zero; or

[0028] The total input charge and total output charge on each electrode are always less than the total charge capacity of that electrode.

[0029] In one embodiment of the present invention, Where d is the horizontal distance between adjacent electrodes.

[0030] In one embodiment of the present invention, θ is between 0° and 90°.

[0031] The device for directional control and separation of charged particles in an electrolyte provided by this invention has the following beneficial technical effects:

[0032] 1. Compared with traditional electrodes

[0033] ① Solved the electrolytic reaction at the electrodes, eliminating the generation of bubbles.

[0034] ② This solves the passivation problem of electrodes after prolonged use, extending the electrode's lifespan.

[0035] ③ This solved the problem of charge capacity limitation.

[0036] ④ It solves the problem of electrode toxicity caused by the adsorption of particles in the fluid, and greatly extends the long-term cycling stability of the electrode.

[0037] 2. Compared with existing electrode schemes

[0038] ① High voltage efficiency,

[0039] ② The speed of controlled charged particles is high, resulting in high separation efficiency.

[0040] ③ It can drive charged nanoparticles, providing very high current driving force at the micrometer and nanometer scales.

[0041] ④ It can precisely control the movement of charged particles.

[0042] ⑤ Its stable operation over long periods of time greatly expands its application scenarios.

[0043] In summary, in microchannel fluid systems, the device for directional control and separation of charged particles in electrolytes provided by this invention has incomparable advantages over existing solutions. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 This is a schematic diagram of a traditional free-flow electrophoresis apparatus;

[0046] Figure 2a This is a schematic diagram of a novel traveling wave electrophoretic separation device;

[0047] Figure 2b for Figure 2a Cross-sectional view of section A-AA;

[0048] Figure 3a This is a schematic diagram of a device for directional control and separation of charged particles in an electrolyte according to an embodiment of the present invention;

[0049] Figure 3b for Figure 3a Schematic diagram of the output voltage of the drive power supply;

[0050] Figure 4a This is a schematic diagram of a device for directional control and separation of charged particles in an electrolyte, according to another embodiment of the present invention.

[0051] Figure 4b for Figure 4a Cross-sectional view of section A-AA;

[0052] Figure 4c for Figure 4a Schematic diagram of the output voltage of the drive power supply;

[0053] Figure 4d for Figure 4a A diagram showing the trajectory of a charged particle. Detailed Implementation

[0054] 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.

[0055] Figure 2a This is a schematic diagram of a novel traveling wave electrophoretic separation device. Figure 2b for Figure 2a Cross-sectional view of A-AA, as shown Figure 2a , 2b As shown, 301 represents a charged particle in the microfluidic system. This charged particle may be a solid, gas, or liquid, including cells, bacteria, microorganisms, proteins, vesicles, etc. 304 represents the outer wall of the microfluidic channel, and 305 represents an electrode using a double-layer capacitor / pseudocapacitor structure. This double-layer capacitor / pseudocapacitor structure solves the problem of bubble generation. The electrode is in direct contact with the medium containing the charged particles, and the electric field generated by the electrode directly acts on the charged particles, improving voltage efficiency and resulting in high charged particle separation efficiency. The electrodes are placed at an angle, with the electric field between the electrodes forming a certain angle with the direction of fluid movement. The generated electric force can be decomposed into a direction parallel to the fluid and a direction perpendicular to the fluid. The electric field parallel to the fluid propels the charged particles forward, while the electric field perpendicular to the fluid is used to accurately filter and distinguish charged particles with different charge-to-mass ratios.

[0056] Figure 2a , 2b In a fluid, there are a certain number of charged particles. These charged particles can be solids, liquids, or bubbles ranging in size from a few nanometers to tens of micrometers. They can carry either positive or negative charges. When these charged particles are subjected to an electric field, they will move relative to the fluid they are in.

[0057] In the above Figure 2a , 2b Based on this, the present invention provides a device for directional control and separation of charged particles in an electrolyte, such as... Figure 3a This is a schematic diagram of a device for directional control and separation of charged particles in an electrolyte according to an embodiment of the present invention, which includes:

[0058] The microfluidic channel 1 has an inlet port 11 and an outlet port 12, through which fluid flows from the inlet port 11 toward the outlet port 12 at a velocity v0. A separation chamber is formed inside the microfluidic channel 1. In this invention, there is no physical isolation between the separation chamber and the electrode chamber. The entire space inside the microfluidic channel 1 can be regarded as a separation chamber. The fluid contains charged particles, which are separated inside the separation chamber. The charged particles can be solids, gases, liquids, or bubbles, including cells, bacteria, microorganisms, proteins, vesicles, etc., and / or the charged particles carry positive or negative charges.

[0059] Two or more sets of electrodes 2, each set containing the same or different number of electrodes. In this embodiment, there are two sets of electrodes: the first set is connected to V1 and consists of two electrodes, and the second set is connected to V2 and consists of one electrode. Each electrode is in contact with the fluid, forming pseudocapacitance and / or double-layer capacitance at the electrode-fluid interface. The electrodes are arranged in parallel inside the microfluidic channel, and their arrangement direction may have a certain angle with the fluid flow direction. This invention avoids electrochemical reactions at the electrode interface through pseudocapacitance and double-layer capacitance. Double-layer capacitance relies on the double layer generated by the adsorption of charged ions in the electrolyte on the electrode surface to achieve charge storage, without the involvement of redox processes, fundamentally eliminating bubble generation. Pseudocapacitance stores and releases electrical energy through a continuous, reversible, phase-change-free Faraday reaction that occurs in the electrode material at a specific potential. No bubbles are generated at the electrode interface, resulting in greater charge capacity and long-term cycling stability. By combining double-layer capacitors and pseudocapacitors, and by arranging a large surface area in the pseudocapacitor electrode and treating the electrode surface to obtain a certain double-layer capacitor interface, the capacitance can be further increased and the electrode efficiency improved.

[0060] Multiple conductor leads 3; and

[0061] Two or more driving power supplies 4 (V1 / V2), each driving power supply is connected to one set of electrodes, the driving power supply generates periodic voltage or current excitation, the voltage or current excitation output by the driving power supply changes within one output cycle, the period, frequency and output voltage and / or current waveform of the driving power supply 4 are adjustable, as are the amplitude, positive-to-negative amplitude ratio and traveling wave speed of the traveling wave electric field.

[0062] Each electrode continuously alternates between charging and discharging, forming a traveling wave electric field with periodically varying amplitude in microfluidic channel 1. The electric force experienced by charged particles in the traveling wave electric field is decomposed into a first component and a second component that are perpendicular to each other. The first component is parallel to the direction of fluid motion and drives the charged particles to move along the direction of the first component. The second component is perpendicular to the direction of fluid motion and separates the charged particles according to different charge-to-mass ratios. The expression for the traveling wave electric field E is:

[0063]

[0064] Where A is the maximum amplitude of the traveling wave electric field, T0 is the period of the traveling wave electric field, θ is the angle between the parallel electrode and the fluid flow direction, and c is the phase of the traveling wave electric field. As shown in Figure 3, the origin is the lower left corner of the first electrode on the left, the x-axis is the fluid flow direction, and the y-axis is the direction rotated 90 degrees counterclockwise from the x-axis. x and y are the abscissa and ordinate of the midpoint of the traveling wave electric field, respectively, and S0 is the period of the electric field intensity relative to the coordinate (x, y).

[0065] The traveling wave electric field E moves at a preset traveling wave speed.

[0066] like Figure 3a As shown, this invention places electrodes inside the separation chamber, utilizing a traveling wave electric field to directly separate charged particles, reducing voltage loss and improving the voltage efficiency of the device. The electrodes are placed below and / or above the separation chamber, with a certain angle between the electrodes and the x-axis (defined as the direction of fluid motion). The electric field generated by the electrodes can directly act on the charged particles without voltage loss, improving electrode efficiency. Under the influence of the electric field, charged particles in the fluid will move parallel to the direction of the electric field; this movement, superimposed on the fluid motion, forms the motion of the charged particles. Due to the different charges and masses of the charged particles, differences in positional displacement along the y-axis (defined as the direction perpendicular to fluid motion) are generated, thereby achieving the separation of different particles in the medium.

[0067] A traveling wave electric field refers to a spatially directional migrating electric field formed by the periodic charging and discharging of multiple electrodes during operation. This electric field moves forward or backward according to voltage changes; that is, the electric field between every two electrodes shifts forward or backward over time. The traveling wave electric field is periodic in both time and space; that is, the direction of the electric field alternates periodically between positive and negative directions at different times and locations. When a charged particle is in a positive electric field, it moves to the upper right, while in a negative electric field, it moves to the lower right. Overall, the trajectory of the charged particle appears as a wave-like undulation with an upward offset. Charged particles with different charge-to-mass ratios exhibit different trajectories due to variations in mobility and velocity within the electric field. By controlling factors such as the velocity, frequency, and phase of the traveling wave electric field, the offset of a specific particle upon leaving the field is canceled out. Charged particles entering the field at different times leave at the same position, and their trajectories tend to converge into a straight line. Other charged particles leave the electric field in a certain waveform, thus separating and enriching specific charged particles. In other words, by controlling factors such as the angle between the electrodes, the magnitude and period of the electric field, the target charged particles can be separated in a straight line or near-straight line (concentrated in a specific region) at certain times.

[0068] During operation, the electrodes generate a traveling wave electric field over time through alternating charging and discharging, controlling charged particles within the fluid. The electrodes operate alternately in anodic and cathodic modes at different times, ensuring that the charge output of each electrode does not exceed its charge capacity. Carrier conversion is completed within the electrode itself, eliminating bubbles and Joule heating generated during electrolysis. This significantly improves electrode voltage efficiency, reduces separation time, and increases separation efficiency.

[0069] A traveling wave electric field E moves sinusoidally forward or backward within microfluidic channel 1, exhibiting a periodic distribution over time t and x, y. The direction and velocity of the traveling wave electric field E are fixed; assuming E is stationary, charged particles must completely pass through both the forward and reverse electric fields during their motion. Figure 3a In the device shown, two sets of electrodes are arranged in the microfluidic channel 1, with the two sets of electrodes placed parallel and staggered. They are respectively connected to driving power supply V1 and driving power supply V2. Figure 3b for Figure 3a The schematic diagram of the output voltage of the driving power supply shows that when V1 and V2 are unequal, there will be alternating electric fields of equal magnitude but opposite direction between the two sets of electrodes, namely Ep=(V2-V1) / (d*sin(θ)) and En=(V1-V2) / (d*sin(θ)). By periodically charging and discharging the electrodes, a traveling wave electric field with asymmetric migration is formed in space, which solves the problem of capacitor charge limitation, increases the voltage threshold, and improves the separation efficiency.

[0070] Charged particles q in microfluidic channel 1 are subjected to electrostatic forces in Ep / En, resulting in a migration velocity v that is proportional to the electric field strength and the charge-to-mass ratio of the charged particles. q+ / v q- There is a deflection angle θ between the parallel electrode and the fluid velocity. This electrostatic force can be decomposed into a force parallel to the fluid velocity v0, i.e., v in the x-direction. x+ And the velocity perpendicular to the fluid velocity v0, i.e., the y-direction v y+ In the reverse electric field, this corresponds to v. x- and v y- .

[0071] Assuming the fluid moves at a constant velocity v0, within the region of action Ep, the horizontal velocity of the charged particles is v0 - v. x+ The direction is to the right, and the velocity in the vertical direction is v. y+ Since the direction is upward, the combined motion of the charged particles is in the first quadrant, i.e., moving to the upper right. Because the electrodes are tilted, the horizontal distance traveled by the charged particles in the Ep interval is greater than d, and the time t1 > d / (v0 - v). x+ Within the effective range of En, the horizontal velocity of the charged particle is v0 + v. x-The direction is to the right, and the velocity in the vertical direction is v. y- Since the direction is downward, the combined motion of the charged particles is in the fourth quadrant, i.e., moving to the lower right. Because the electrodes are tilted, the horizontal distance the charged particles travel in the Ep interval is less than d, and the time t2... <d / (v0+v x- Therefore, it can be inferred that t1 > d / (v0 - v). x+ )>d / (v0+v x- )>t2. v y+ and v y- When charged particles of equal magnitude but opposite direction pass through a pair of opposing electric fields, Ep and En, their voltage levels change due to the difference in the duration of the interaction. y+ *t1>v y- *t2, meaning the vertical migration distance in the Ep interval is greater than the vertical migration distance in the En interval, indicates that the charged particle moves vertically in the electric field. This velocity is determined by the magnitude of the electric field Ep / En, the charge-to-mass ratio of the charged particle, the viscosity coefficient of the liquid, the electrode deflection angle θ, and parameters such as the flow velocity v0 and the electrode distance d.

[0072] Charged particles with different charge-to-mass ratios undergo controllable vertical motion after passing through paired electric field regions. The amplitude of this motion is independent of the order in which Ep / En are applied; therefore, by periodically changing the order of Ep / En, i.e., periodically changing the voltages V1 / V2, the electrodes only need to provide a reciprocating driving current to the fluid. Under the condition of constant electric field amplitude, the charge capacity load requirement of the electrodes can be reduced by decreasing the switching period; a typical period is set to be no less than v0 / (2*d).

[0073] By adjusting the voltage amplitude of V1 / V2, controlling the magnitude of Ep / En, and the specific electric field waveform, charged particles with different charge-to-mass ratios in the medium can be precisely manipulated.

[0074] Figure 4a This is a schematic diagram of a device for directional control and separation of charged particles in an electrolyte, according to another embodiment of the present invention. Figure 4a , 4b As shown, 301 is the outer wall of the microfluidic channel, 302 and 303 are electrodes, 304 is a charged particle, 306 is a conductor lead, and V1 to V4 are driving power sources. The fluid moves at a fixed velocity v, and electrodes 302 and 303 alternately charge and discharge. The angle between the direction of the electric field E between the electrodes and the fluid velocity v is greater than zero.

[0075] Figure 4a Four electrodes were used as a group. By applying electrical signals with a certain phase difference to each of the four electrodes, a traveling wave electric field was generated in the fluid. Figure 4c for Figure 4a The schematic diagram of the output voltage of the driving power supply shows the expression for the resulting traveling wave electric field. This indicates that the electric field exhibits a periodic distribution in time t and along the x and y directions. k = tanθ, where θ is the angle between the parallel electrode and the horizontal direction, A is the amplitude of the electric field, T0 is the period of the electric field intensity with respect to time t, S0 is the period of the electric field intensity with respect to x and y, and c is the phase. θ can be between 0° and 90°, and the motion of charged particles can be controlled by adjusting θ. The motion of charged particles in a traveling wave electric field involves passing through many sets of alternating positive and negative electric fields, resulting in a deflection perpendicular to the flow channel direction.

[0076] Figure 4a The setting method of the x-axis and y-axis and Figure 3a Similarly, the velocity of the charged particle in the x-direction is: x′(t) = -m*E(t, x, y)*sinθ + v0; and the velocity in the y-direction is: y′(t) = m*E(t, x, y)*cosθ. Substituting the electric field E into these equations, the trajectory of the charged particle can be calculated. The displacement of the charged particle in the y-direction fluctuates upwards with increasing time. Since the general solution of this differential equation is not easily obtained, MATLAB is used to find its numerical solution.

[0077] Figure 4d This is a top view of the electric field. The dashed lines in the diagram represent the trajectories of charged particles. Charged particles in the electric field fluctuate and shift upwards over time, the magnitude of which is influenced by the frequency and phase-related parameters of the electric field. Charged particles entering the electric field at different times differ by a time interval t0, resulting in a phase difference in their trajectory equations. By adjusting factors such as the angle and velocity of the traveling wave electric field, the phase-induced shift in the y-direction is offset at the end position of the electric field. The charged particles leave the electric field at the same position, exhibiting a near-linear exit, thus better enriching specific charged particles. Other charged particles have longitudinal displacement deviations c. Charged particles entering at different times will fluctuate in their exit positions, exhibiting a wave-like pattern. Differences in velocity and trajectory lead to variations in the displacement distance of different charged particles within the flow channel, thus distinguishing them from specific charged particles upon exiting the electric field, completing the separation of charged particles within the medium.

[0078] For charged particles with different charge-to-mass ratios, their motion speed and trajectory are different. By adjusting the input position of the charged particles and the phase of the traveling wave electric field, the motion of different charged particles and the timing when the displacement deviation of a specific charged particle disappears can be controlled. Different charged particles have different displacements in the y-direction, so as to complete the separation of charged particles.

[0079] In one embodiment of the present invention, during one or more cycles of the traveling wave electric field, the total input current on each electrode is equal to the total output current, that is, the net input current and net output current on each electrode are both zero; or

[0080] The total input charge and total output charge on each electrode are always less than the charge capacity of that electrode.

[0081] In one embodiment of the present invention, Where d is the horizontal distance between adjacent electrodes.

[0082] In one embodiment of the present invention, θ is between 0° and 90°.

[0083] The device for directional control and separation of charged particles in an electrolyte provided by this invention has the following beneficial technical effects:

[0084] 1. Compared with traditional electrodes

[0085] ① Solved the electrolytic reaction at the electrodes, eliminating the generation of bubbles.

[0086] ② This solves the passivation problem of electrodes after prolonged use, extending the electrode's lifespan.

[0087] ③ This solved the problem of charge capacity limitation.

[0088] ④ It solves the problem of electrode toxicity caused by the adsorption of particles in the fluid, and greatly extends the long-term cycling stability of the electrode.

[0089] 2. Compared with existing electrode schemes

[0090] ① High voltage efficiency,

[0091] ② The speed of controlled charged particles is high, resulting in high separation efficiency.

[0092] ③ It can drive nanoparticles to carry electrons, providing very high current driving force at the micron and nanoscale.

[0093] ④ It can precisely control the movement of charged particles.

[0094] ⑤ Its stable operation over long periods of time greatly expands its application scenarios.

[0095] In summary, in microchannel fluid systems, the device for directional control and separation of charged particles in electrolytes provided by this invention has incomparable advantages over existing solutions.

[0096] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of one embodiment, and the modules or processes shown in the drawings are not necessarily essential for implementing the present invention.

[0097] Those skilled in the art will understand that the modules in the apparatus of the embodiments can be distributed in the apparatus of the embodiments as described in the embodiments, or they can be located in one or more devices different from this embodiment with corresponding changes. The modules of the above embodiments can be combined into one module, or they can be further divided into multiple sub-modules.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for directional control and separation of charged particles in an electrolyte, characterized in that, include: Microfluidic channels have multiple ports, including one or more inlet ports and one or more outlet ports, to supply fluid at a certain velocity. The fluid flows from the inlet port toward the outlet port, and a separation chamber is formed inside the microfluidic channel. The fluid contains charged particles, which are separated inside the separation chamber. Two or more sets of electrodes, each set having the same or different number of electrodes, each electrode being in contact with the fluid and forming pseudocapacitance and / or double-layer capacitance at the interface between the electrode and the fluid, the electrodes being arranged in parallel inside the microfluidic channel and having a certain angle between the arrangement direction and the flow direction of the fluid. Multiple conductor leads; and Two or more driving power supplies, each driving power supply is connected to one set of electrodes, the driving power supply generates periodic voltage or current excitation, and the voltage or current excitation output by the driving power supply changes within one output cycle. Each electrode continuously alternates between charging and discharging, forming a traveling wave electric field with periodically varying amplitude within the microfluidic channel. The electric force experienced by charged particles in this traveling wave electric field is decomposed into two mutually perpendicular components: the first component is parallel to the direction of fluid motion and drives the charged particles to move along this direction; the second component is perpendicular to the direction of fluid motion and separates the charged particles according to different charge-to-mass ratios. The expression for the traveling wave electric field E is: ， in, This represents the maximum amplitude of the traveling wave electric field. Let be the period of the traveling wave electric field. The angle between the parallel electrode and the direction of fluid flow. Let x represent the phase of the traveling wave electric field. The origin is the location of the lower left corner of the first electrode on the left. The x-axis is the direction of fluid flow, and the y-axis is the direction rotated 90 degrees counterclockwise from the x-axis. x and y are the abscissa and ordinate of the midpoint of the traveling wave electric field, respectively. Let be the period of the electric field intensity relative to the coordinates (x, y). The traveling wave electric field E moves at a preset traveling wave speed. By controlling the speed, frequency and phase of the traveling wave electric field, the offset of a specific particle when leaving the electric field is canceled out. Charged particles that enter the electric field at different times are at the same position when leaving the electric field, and the trajectory of the charged particles tends to be a straight line.

2. The apparatus for directional control and separation of charged particles in an electrolyte according to claim 1, characterized in that, Charged particles include solids, gases, liquids, or bubbles, including cells, bacteria, microorganisms, proteins, vesicles, and / or Charged particles carry either a positive or negative charge.

3. The apparatus for directional control and separation of charged particles in an electrolyte according to claim 1, wherein the period and frequency of the driving power supply, as well as the output voltage and / or current waveform, are all adjustable. The amplitude, positive-to-negative amplitude ratio, and traveling speed of the traveling wave electric field are all adjustable.

4. The apparatus for directional control and separation of charged particles in an electrolyte according to claim 1. During one or more cycles of the traveling wave electric field, the total input current on each electrode is equal to the total output current, meaning that the net input current and net output current on each electrode are both zero; or The total input charge and total output charge on each electrode are always less than the total charge capacity of that electrode.

5. The apparatus for directional control and separation of charged particles in an electrolyte according to claim 1. , where d is the horizontal distance between adjacent electrodes.

6. The apparatus for directional control and separation of charged particles in an electrolyte according to claim 1. Between 0° and 90°.

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