Microfluidic intelligent control system and control method based on holographic light trap

Abstract

The present invention relates to a microfluidic intelligent control system and control method based on a holographic light trap. The purpose of the present invention is to solve the problems in microfluidic systems such as the difficulty in controlling cells in a local flow channel, the difficulty in controlling the flow of cells in multiple locations, directions, and speeds in a microfluidic chip, the poor reliability and stability of cell control in the fluid, high manufacturing costs, high difficulty, and complex operation. The method comprises the following steps: obtaining a target light field pattern and a corresponding phase map; loading the phase map onto a spatial light modulator; emitting laser light from a laser transmitter, which passes through a beam expander, a spatial light modulator, a 4F system, a beam splitter, and a microscope objective lens in sequence to generate a target light field under the microscope objective lens, and projecting the target light field pattern onto the plane of the microfluidic chip; observing and recording the target light field pattern with a camera through the microscope objective lens; and controlling the cells or particles in the microfluidic chip to enter a target outlet based on the target light field pattern.

Description

Technical Field

[0001] The invention relates to a microfluid intelligent control system and a control method. Background Art

[0002] Microfluidics is a technology for studying and manipulating micron-scale fluids, involving processes such as sample processing, fluid manipulation, and analysis of tiny volumes. It utilizes micron-scale channels, valves, pumps, and control systems to precisely manipulate and operate microfluidics. Microfluidics is widely used in fields such as biomedicine, chemical analysis, and materials science.

[0003] The core of microfluidics is the microfluidic chip, which is a tiny chip that integrates a network of microchannels and control elements. Microfluidic chips are typically manufactured using micro-nanofabrication technologies such as photolithography, lithography, and polymerization. The microchannels and structures on the chip surface can be designed and manufactured according to the needs of specific applications. In a microfluidic chip, fluids can be guided and controlled through microchannels. Microfluidic chips typically contain input and output ports through which samples can be introduced and processed fluids can be discharged. The microchannel network can guide fluids to different areas for operations such as mixing, separation, reaction, and detection.

[0004] In current microfluidic systems, complex fluid manipulation can only be achieved through complex microchannel structures, and only full-channel manipulation is possible, not partial channel manipulation. Due to the microstructure of the microchannels and the complex fluid manipulation, components such as microvalves, micropumps, and connectors in the system are prone to failure or wear, which can easily affect the stability and reliability of the system.

[0005] The basic principle of fluid control: Most materials, including metals, polymers, and ceramics, absorb light of specific wavelengths under ambient conditions. The absorbed photon energy excites electrons, which then undergo nonradiative decay, converting the energy into heat. Therefore, laser irradiation of the nanostructures of photothermal materials can maintain strong temperature gradients, enabling manipulation of fluids, particles, and cells.

[0006] The manipulation of fluids, particles, and cells by temperature gradient fields mainly relies on the following physical mechanisms:

[0007] (1) Thermophoresis. It describes the thermal directional migration of colloidal species in a fluid environment under a temperature gradient field. Figure 3 In (a), the migration speed is Where D_T is the thermophoretic mobility, is the temperature field gradient. The migration direction is determined by the Soret coefficient S T Decision: When S T When S > 0, the suspended particles hate heat and move from the hot area to the cold area; when ST When S<0, the particles are thermophilic and move from the cold area to the hot area. Generally speaking, most colloidal particles are thermophilic under ambient conditions. T The size of also reflects the size of the particle concentration gradient in the temperature field.

[0008] (2) Thermoelectric field. When ions are added to a colloidal particle suspension, different ions migrate at different speeds and directions under a temperature gradient through thermophoresis. Figure 3 In (b), ions with opposite charges are spatially separated. When the ion redistribution reaches a steady state in a closed system, a thermoelectric field is established. By controlling the type of ions and the surface charge of the particles, colloidal particles can be captured or propelled on demand under the photoconductive thermoelectric field. In addition, the polarization of pure solvents (such as water) under temperature fields can also generate thermoelectric fields.

[0009] (3) Diffusion phoresis. Diffusion phoresis describes the transport of colloidal particles under a solute concentration gradient. Figure 3 Figure (c). Under a temperature gradient, different components have different drift velocities depending on their thermophoretic mobility. Because small molecules typically have a larger Brownian diffusion coefficient, D, they migrate faster than colloidal particles, resulting in a stable concentration gradient parallel to the temperature gradient. This concentration gradient of small molecules exerts osmotic pressure, causing the suspended colloids to move towards the molecular depletion zone under the action of an exhaustion force. Summary of the Invention

[0010] The purpose of the present invention is to solve the problems in microfluidic systems such as difficulty in controlling cells in local flow channels, difficulty in controlling fluids at multiple locations, in different directions and at different speeds in microfluidic chips, poor reliability and stability of cell control in fluids, high manufacturing costs, great difficulty and complex operation, and to propose a microfluidic intelligent control system and control method based on holographic light traps.

[0011] A microfluidic intelligent control system based on a holographic light trap comprises: a holographic light trap generating component (1), a microfluidic chip (2), and a shooting component (3);

[0012] The holographic light trap generation component (1) includes: a laser emitter (11), a spatial light modulator (12), a 4F system (13), and a beam expander;

[0013] The microfluidic chip (2) comprises: a microfluidic liquid inlet (21), a cell 1 outlet (22), a cell 2 outlet (23), and a cell 3 outlet (24);

[0014] The shooting component (3) includes a microscope objective lens (31), a spectroscope (32), and a camera (33).

[0015] The specific process of the microfluidic intelligent control method based on holographic light trap is as follows:

[0016] Step 1: Obtain the target light field pattern

[0017] Step 2: Process the target light field pattern to obtain a holographic light trap image corresponding to the target light field pattern;

[0018] Step 3: Loading a holographic light trap pattern on the spatial light modulator (12), the laser emitter (11) emits laser light which passes through the beam expander, the spatial light modulator (12), the 4F system (13), the spectroscope, and the microscope objective lens (31) in sequence, and generates a target light field pattern at the microscope objective lens (31), and the target light field pattern is projected onto the plane of the microfluidic chip (2);

[0019] The camera (33) observes and records the target light field pattern through the microscope objective lens (31);

[0020] SLM can be understood as a special display that can load images. Loading a specific image can modulate the light field. The modulated light field acts on the sample surface through the optical lens and objective lens, and the sample surface will form the light trap we want to modulate.

[0021] Step 4: Based on the target light field pattern, cells or particles in the microfluidic chip are enabled to enter the target outlet.

[0022] The beneficial effects of the present invention are:

[0023] The purpose of the present invention is to realize the projection of light fields of arbitrary shapes at any position of the microchannel through holographic computing technology, thereby forming a specific temperature gradient field and further manipulating the fluid in the microchannel in real time.

[0024] The present invention can realize local real-time control of the microfluidic chip: it only needs to project the light field to the position to be controlled to realize the fluid control at the corresponding position.

[0025] The present invention can easily realize fluid control in different directions and speeds at multiple positions of a microfluidic chip: by projecting different patterns onto multiple positions that need to be controlled, fluid control in different directions and speeds at multiple positions can be realized.

[0026] The present invention has higher reliability and stability: it only needs to control the fluid at the desired position, and is not affected by failures or wear in other parts of the entire flow channel.

[0027] The present invention has low manufacturing cost: complex fluid operations can be achieved by only making simple flow channels, and there is no need to design a complex flow channel system.

[0028] The present invention has the advantages of simple operation and low threshold for use: there is no need to design a complex microfluidic system, and complex microfluidic manipulation can be achieved by simply inputting a corresponding motion pattern.

[0029] The present invention has a wide range of applications: it can realize microfluidic valve, microfluidic pump, microfluidic sorting and other operation modes.

[0030] This invention provides a method for real-time control of fluid motion within a microchannel. Using holographic computing technology, real-time light field modulation is achieved, which in turn modulates the temperature gradient field in real time, thereby enabling precise manipulation of fluids, particles, cells, and other objects. This invention enables the control of fluid motion in different forms within a microchannel within the same timeframe, in different zones. This operating system and method have extremely important applications in the field of microfluidics. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Flowchart of the present invention;

[0032] Figure 2 This is a structural diagram of the microfluidic intelligent control system based on holographic light traps of the present invention. The yellow part is the imaging light path, which is used to record observations.

[0033] Figure 3 Figures for thermophoresis, thermoelectric field, and diffusion phoresis. (a) shows the thermal directional migration of colloidal species in a fluid environment under a temperature gradient field. (b) shows the migration of different ions at different speeds and directions through thermophoresis under a temperature gradient. (c) shows the transport of colloidal particles under a solute concentration gradient. E is the electric field strength, V is the particle velocity, is the concentration gradient;

[0034] Figure 4 A structural diagram of the components for generating a holographic light trap;

[0035] Figure 5 Schematic diagram of microfluidic valve;

[0036] Figure 6 Rectangular light bar patterns with different movement directions, (a) is a rectangular light bar pattern, (b) is a moving rectangular light bar pattern;

[0037] Figure 7 There are four different types of cells or particles in a certain working area of ​​the microfluidic chip, and a sorting diagram of different types of cells or particles is realized. DETAILED DESCRIPTION

[0038] Specific embodiment 1: The microfluidic intelligent control system based on the holographic light trap of this embodiment includes: a holographic light trap generating component (1), a microfluidic chip (2), and a shooting component (3);

[0039] The holographic light trap generation component (1) includes: a laser emitter (11), a spatial light modulator (SLM) (12), a 4F system (13), and a beam expander;

[0040] The microfluidic chip (2) comprises: a microfluidic liquid inlet (21), a cell 1 outlet (22), a cell 2 outlet (23), and a cell 3 outlet (24);

[0041] The shooting component (3) includes a microscope objective lens (31), a spectroscope (32), and a camera (33).

[0042] Specific embodiment 2: This embodiment differs from specific embodiment 1 in that the laser emitter (11) emits laser light;

[0043] The wavelength of the laser is 671nm;

[0044] The holographic light trap pattern (phase pattern) is loaded on the spatial light modulator (SLM) (12) );

[0045] The laser passes through a beam expander, a spatial light modulator (SLM) (12), a 4F system (13), a beam splitter (32), and a microscope objective lens (31) in sequence, and generates a target light field pattern at the microscope objective lens (31), and the target light field pattern is projected onto the plane of the microfluidic chip (2);

[0046] The camera (33) observes and records the target light field pattern through the microscope objective lens (31).

[0047] Other steps and parameters are the same as those in the first embodiment.

[0048] Specific embodiment three: This embodiment differs from specific embodiment two in that a photosensitive substrate (a commonly used porous gold film plated on glass, which has a high photothermal conversion efficiency) is provided at the bottom of the microfluidic chip (2) for photothermal conversion.

[0049] Specific embodiment 4: The specific process of the microfluidic intelligent control method based on holographic light trap in this embodiment is as follows:

[0050] Step 1: Obtain the target light field pattern

[0051] Step 2: Process the target light field pattern to obtain a holographic light trap image (phase image) corresponding to the target light field pattern;

[0052] Step 3: Load the holographic light trap pattern (phase pattern) on the spatial light modulator (SLM) (12) ), the laser emitter (11) emits laser light which passes through the beam expander, the spatial light modulator (SLM) (12), the 4F system (13), the spectroscope, and the microscope objective lens (31) in sequence, and generates a target light field pattern at the microscope objective lens (31), and the target light field pattern is projected onto the plane of the microfluidic chip (2);

[0053] The camera (33) observes and records the target light field pattern through the microscope objective lens (31);

[0054] SLM can be understood as a special display that can load images. Loading a specific image can modulate the light field. The modulated light field acts on the sample surface through the optical lens and objective lens, and the sample surface will form the light trap we want to modulate.

[0055] Step 4: Based on the target light field pattern, cells or particles in the microfluidic chip are enabled to enter the target outlet.

[0056] Specific embodiment 5: This embodiment differs from specific embodiment 4 in that in step 2, the target light field pattern is processed to obtain a phase map corresponding to the target light field pattern; the specific process is as follows:

[0057] The GS algorithm is used to process the target light field pattern to obtain the phase map corresponding to the target light field pattern.

[0058] Other steps and parameters are the same as those in the fourth embodiment.

[0059] Specific embodiment 6: This embodiment differs from specific embodiment 5 in that in step 4, cells or particles in the microfluidic chip are enabled to enter the target outlet based on the target light field pattern; the specific process is:

[0060] The microfluidic valve operation in the microfluidic chip is realized based on the holographic light trap pattern; the specific process is as follows:

[0061] When a certain working area in the microfluidic chip requires type A cells or particles to enter the flow channel of outlet A, the holographic light trap image (phase image) is loaded. ) Projecting a target light field pattern at outlets B and C will generate a repulsive force to prevent type A cells or particles from entering the flow channels of outlets B and C. All type A cells or particles enter the flow channel of outlet A;

[0062] When a certain working area in the microfluidic chip requires type B cells or particles to enter the flow channel of outlet B, the target light field pattern of the desired outlet B is removed and moved to outlet A. The target light field pattern will generate a repulsive force to prevent type B cells or particles from entering the flow channels of outlets A and C, and all type B cells or particles enter the flow channel of outlet B.

[0063] When a certain working area in the microfluidic chip requires type C cells or particles to enter the flow channel of outlet C, the target light field pattern of the desired outlet C is removed and moved to outlet B. The target light field pattern will generate a repulsive force to prevent type C cells or particles from entering the flow channels of outlets A and B, and all type C cells or particles enter the flow channel of outlet C.

[0064] The switch of the intelligent photothermal valve can be realized by removing the target light trap image and moving the target light trap image position. Figure 5 .

[0065] Other steps and parameters are the same as those in the fifth embodiment.

[0066] Specific embodiment seven: This embodiment differs from specific embodiment five in that in step four, cells or particles in the microfluidic chip are enabled to enter the target outlet based on the target light field pattern; the specific process is as follows:

[0067] The microfluidic pump operation in the microfluidic chip is realized based on the holographic optical trap pattern; the specific process is as follows:

[0068] When a certain working area in the microfluidic chip requires type A cells or particles to enter the flow channel of outlet A, the holographic light trap image (phase map) refreshed in real time is loaded. ) A dynamic target light field pattern is projected onto the microchannel of the microfluidic chip. Cells or particles enter the dynamic target light field pattern loading area. The cells or particles in the dynamic target light field pattern loading area are subjected to the photothermal repulsion and move to the low light intensity area between the two high light intensity light bars of the target light field pattern. They move dynamically with the dynamic target light field pattern. This achieves the effect of a microfluidic pump; Figure 6 .

[0069] Other steps and parameters are the same as those in the fifth embodiment.

[0070] Specific embodiment eight: This embodiment differs from specific embodiment seven in that the dynamic target light field pattern is composed of n rectangular light strips; n is a positive integer;

[0071] The rectangular light strip is divided into a high-intensity area and a low-intensity area (a part with a bright strip and a part without a bright strip);

[0072] Set the light power density threshold to 0.1mW / um 2 ;

[0073] The area in the rectangular light strip where the light power density is less than the threshold is the low light intensity area;

[0074] The area in the rectangular light strip where the light power density is greater than or equal to the threshold is the high light intensity area;

[0075] The movement direction and speed of cells or particles are determined by the movement direction and speed of the bright stripe portion of the dynamic target light field pattern.

[0076] Other steps and parameters are the same as those in the seventh embodiment.

[0077] Specific embodiment nine: This embodiment differs from specific embodiment five in that in step four, cells or particles in the microfluidic chip are enabled to enter the target outlet based on the target light field pattern; the specific process is as follows:

[0078] The microfluidic sorting operation in the microfluidic chip is realized based on the holographic optical trap image; the specific process is as follows:

[0079] There are M kinds of cells or particles in an open working area of ​​the microfluidic chip. When the M kinds of cells or particles need to be placed into M different outlets, the position of each cell or particle is first obtained by the camera, and the holographic light trap image (phase map) is loaded. ) Projecting a target light field pattern at the location of each cell or particle to capture the cells or particles at the corresponding location, and enabling each type of cell or particle to enter different exits by moving the target light field pattern;

[0080] M is a positive integer;

[0081] The target light field pattern is a circular light trap pattern, a diamond light trap pattern, a square light trap pattern or a triangular light trap pattern.

[0082] Here we take four types of cells or particles as an example. When these four cells or particles need to be placed in different outlets respectively, the position of each cell or particle is first obtained through the camera. When type A cells or particles need to enter the flow channel of outlet A, a circular light trap is projected at the corresponding position to capture the cell or particle, and the operation of type A cells or particles entering the flow channel of outlet A is achieved through the movement of the circular light trap; at the same time, it is possible to cast a circular light trap at the same time to capture type B cells or particles moving into the flow channel of outlet B. At the same time, it is possible to cast a circular light trap at the same time to capture type C cells or particles moving into the flow channel of outlet C. At the same time, it is possible to cast a circular light trap at the same time to capture type D cells or particles moving into the flow channel of outlet D. Figure 7 ;

[0083] Circular light traps are OK, and light traps of other shapes are OK too. Figure 7 Medium shapes are used to represent cell or particle types.

[0084] Other steps and parameters are the same as those in the fifth embodiment.

[0085] The above information can achieve the following:

[0086] 1. Project a fixed-shape light trap pattern at a desired position in the microchannel. The repulsive force generated by the light and heat will prevent the fluid from passing through the projected position, thus forming a microfluidic valve. When the projected light trap pattern is removed, the valve opens and the fluid can pass through again. Figure 5 .

[0087] 2. Project a moving light trap pattern at a certain position in the microchannel. The repulsive force generated by the light and heat will push the fluid to move in the corresponding direction, thereby achieving the effect of a microfluidic pump. The direction and speed of the fluid movement are determined by the direction of the pattern movement and the refresh rate, such as Figure 6 .

[0088] 3. Project multiple light trap patterns at the required position in a certain section of the microchannel. At this time, the capture force generated by photothermal energy can capture particles, cells or particles and other objects. The movement of the light trap can realize the sorting of different types of particles and cells, such as Figure 7 .

[0089] Example:

[0090] Example 1:

[0091] 1. Steps for using the microfluidic valve: A solution containing one type of cells or particles is passed through the microchannel. When one type of cells or particles is required to enter the desired outlet 3, a holographic light trap is projected at the undesired outlets 1 and 2. The light trap then generates a repulsive force to prevent cells or particles from entering the flow channel at the undesired outlets 1 and 2, while all cells or particles of one type enter the desired outlet 3. When other types of cells or particles need to enter other outlets, the light trap can be removed or moved to switch the intelligent photothermal valve. Figure 5 .

[0092] 2. How to use the microfluidic pump: First, generate a dynamic light trap pattern, which consists of n rectangular light strips that move vertically. Cells or particles that enter the dynamic light trap loading area are subjected to the photothermal repulsion and move to the low light intensity area between the two high light intensity light strips. As the light strips move dynamically, they move in the direction of the light strips. When the direction of movement needs to be changed, rectangular light strip patterns with different movement directions are loaded, such as Figure 6 .

[0093] 3. Microfluidic sorting steps: In a certain working area of ​​the microfluidic chip, there are many different types of cells or particles. Figure 7 As shown, by adjusting the laser power and solution environment, the light trap generates a capturing force, and by dynamically loading the phase image, the light trap carries the target cells or particles to the target outlet, thereby achieving the sorting of different types of particles and cells.

[0094] Example 2:

[0095] Capture object size: 50nm~20um scale range

[0096] Taking 2um PS (polystyrene) particles as the target, the light trap illumination power density is 0.05-0.4mW / um 2 Can capture 2um PS particles;

[0097] The capture experiment uses a CTAC (cetyltrimethylammonium chloride) solution to provide a solution environment, and the solution concentration range is 0.5 mM-15 mM (greater than or equal to 0.5 mM and less than or equal to 15 mM).

[0098] To evaluate the capture capability, the escape velocity of captured PS particles was measured using a precisely speed-controlled motorized sample stage (chip). A laser beam was used to capture a single PS particle, and a certain movement speed was set for the motorized sample stage to exert resistance (Stokes drag, i.e., the resistance of water when the particle moves) on the captured particle. The critical speed at which the maximum capture force of the particle is balanced with the resistance is defined as the escape velocity.

[0099] The particle moves at a speed less than the escape velocity.

[0100] Example 3:

[0101] 2um PS particles in 1mM CTAC solution environment, at 0.05mW / um 2 Under the light power density, the light trap movement speed (escape velocity) can reach up to 23um / s. As the light power density increases, the escape velocity also increases. At 0.2mW / um 2 The escape velocity reaches 50um / s under the light power density.

[0102] The escape velocity is also related to the solution concentration. Under the same illumination power density and object size, a higher CTAC solution concentration will reduce the escape velocity.

[0103] The escape velocity is also related to the size of the operating particles. Under the same light power density and solution concentration, smaller particles have a higher escape velocity.

[0104] The particle moves at a speed less than the escape velocity.

[0105] Example 4:

[0106] For the repulsion experiment, the solution environment was replaced with SDS (sodium dodecyl sulfate) solution with a concentration range of 0.5 mM to 15 mM;

[0107] Taking 2um PS particles as the target, the light trap illumination power density is 0.05-0.4mW / um 2 It can reject 2um PS particles.

[0108] The present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. Microfluidic intelligent control method based on holographic light trap, the system used includes: Holographic light trap generation component (1), microfluidic chip (2), and shooting component (3); The holographic light trap generation component (1) includes: a laser emitter (11), a spatial light modulator (12), a 4F system (13), and a beam expander; The microfluidic chip (2) includes: a microfluidic liquid inlet (21), a cell 1 outlet (22), a cell 2 outlet (23), and a cell 3 outlet (24); The shooting component (3) includes: a microscope objective lens (31), a spectroscope (32), and a camera (33); The specific process of the control method is: Step 1: Obtain the target light field pattern ; Step 2: Process the target light field pattern to obtain a holographic light trap image corresponding to the target light field pattern; Step 3: Load the holographic light trap pattern on the spatial light modulator (12); the laser emitter (11) emits laser light which passes through the beam expander, the spatial light modulator (SLM) (12), the 4F system (13), the spectroscope, and the microscope objective lens (31) in sequence; the target light field pattern is generated at the microscope objective lens (31); and the target light field pattern is projected onto the plane of the microfluidic chip (2); The camera (33) observes and records the target light field pattern through the microscope objective lens (31); Step 4: Based on the target light field pattern, cells or particles in the microfluidic chip are enabled to enter the target outlet. The specific process is as follows: When a certain working area in the microfluidic chip requires type A cells or particles to enter the flow channel of outlet A, the target light field pattern is projected at outlets B and C by loading the holographic light trap image. The target light field pattern will generate a repulsive force to prevent type A cells or particles from entering the flow channels of outlets B and C. All type A cells or particles enter the flow channel of outlet A. When a certain working area in the microfluidic chip requires type B cells or particles to enter the flow channel of outlet B, the target light field pattern of the desired outlet B is removed and moved to outlet A. The target light field pattern will generate a repulsive force to prevent type B cells or particles from entering the flow channels of outlets A and C, and all type B cells or particles enter the flow channel of outlet B. When a certain working area in the microfluidic chip requires type C cells or particles to enter the flow channel of outlet C, the target light field pattern of the desired outlet C is removed and moved to outlet B. The target light field pattern will generate a repulsive force to prevent type C cells or particles from entering the flow channels of outlets A and B, and all type C cells or particles enter the flow channel of outlet C.

2. The microfluidic intelligent control method based on holographic light trap according to claim 1, characterized in that: The laser emitter (11) emits laser light; The wavelength of the laser is 671nm; A holographic light trap pattern is loaded on the spatial light modulator (12); The laser light passes through a beam expander, a spatial light modulator (12), a 4F system (13), a beam splitter (32), and a microscope objective lens (31) in sequence, and a target light field pattern is generated in the microscope objective lens (31), and the target light field pattern is projected onto the plane of the microfluidic chip (2); The camera (33) observes and records the target light field pattern through the microscope objective lens (31).

3. The microfluidic intelligent control method based on holographic light trap according to claim 2, characterized in that: A photosensitive substrate is provided at the bottom of the microfluidic chip (2).

4. The microfluidic intelligent control method based on holographic light trap according to claim 3, characterized in that: In step 2, the target light field pattern is processed to obtain a phase map corresponding to the target light field pattern; the specific process is: The GS algorithm is used to process the target light field pattern to obtain the phase map corresponding to the target light field pattern.

5. The microfluidic intelligent control method based on holographic light trap according to claim 4, characterized in that: In step 4, cells or particles in the microfluidic chip are enabled to enter the target outlet based on the target light field pattern; the specific process is: When a certain working area in the microfluidic chip requires type A cells or particles to enter the flow channel of outlet A, a dynamic target light field pattern is projected on the microchannel of the microfluidic chip by loading the holographic light trap pattern. The cells or particles enter the dynamic target light field pattern loading area. The cells or particles in the dynamic target light field pattern loading area are subjected to photothermal repulsion and move to the low light intensity area between the two high light intensity light bars of the target light field pattern, and move dynamically with the dynamic target light field pattern.

6. The microfluidic intelligent control method based on holographic light trap according to claim 5, characterized in that: The dynamic target light field pattern is composed of n rectangular light strips; n is a positive integer; The rectangular light strip is divided into high-intensity and low-intensity areas; Set the light power density threshold to 0.1 mW / μm 2 ; The area in the rectangular light strip where the light power density is less than the threshold is the low light intensity area; The area in the rectangular light strip where the light power density is greater than or equal to the threshold is the high light intensity area; The movement direction and speed of cells or particles are determined by the movement direction and speed of the bright stripe portion of the dynamic target light field pattern.

7. The microfluidic intelligent control method based on holographic light trap according to claim 6, characterized in that: In step 4, cells or particles in the microfluidic chip are enabled to enter the target outlet based on the target light field pattern; the specific process is: In a microfluidic chip, an open working area contains M types of cells or particles. When the M types of cells or particles need to be placed into M different exits, the position of each cell or particle is first acquired through a camera. A target light field pattern is projected at the position of each cell or particle by loading a holographic light trap image to capture the cell or particle at the corresponding position. The target light field pattern is then moved to allow each type of cell or particle to enter the different exits. M is a positive integer; The target light field pattern is a circular light trap pattern, a diamond light trap pattern, a square light trap pattern or a triangular light trap pattern.

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