Multi-degree-of-freedom adjustable surface acoustic wave microfluidic acoustic tweezers device and method

Abstract

The invention provides a multi-degree-of-freedom adjustable surface acoustic wave microfluidic acoustic tweezers device, belongs to the technical field of microfluidics, and can realize the function of dynamically adjusting multiple key parameters such as acoustic wave propagation speed, angle and structure of a microfluidic device. The system mainly comprises a surface acoustic wave generation module, a surface acoustic wave action module and a multi-dimensional adjustment module. The surface acoustic wave generation module mainly comprises a piezoelectric material substrate and a flexible interdigital electrode. The surface acoustic wave action module is composed of a PDMS micro-channel or a PDMS micro-ring and is mainly determined by the function of the acoustic tweezers device. The multi-dimensional adjusting module can freely adjust the relative position of the flexible interdigital electrode and the position and the angle of the flexible interdigital electrode relative to the piezoelectric material substrate, and then the propagation speed and the acting effect of sound waves are controlled. Different microfluidic application requirements can be met through multi-dimensional adjustment of the flexible interdigital electrode and the piezoelectric material substrate.

Description

Technical Field

[0001] The invention relates to the field of acoustic wave devices and microfluids, and in particular to a multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device and method. Background Art

[0002] With the rapid development of biochemical analysis, tissue engineering and other fields, microfluidics has become a research hotspot at home and abroad. Compared with acoustic tweezers technology, microfluidics has a greater micro-nanoparticle force for cell manipulation. Surface acoustic wave microfluidics combines ultrasound technology with microfluidics technology, and uses surface acoustic waves or bulk acoustic waves to manipulate target micro-nanoparticles in a non-contact, label-free and highly biocompatible manner. It has very broad application prospects in biomedicine, environmental testing and drug screening and testing.

[0003] 1. However, there are still some problems with surface acoustic wave microfluidic devices, which limit their large-scale popularization and application. In existing devices, the interdigitated electrodes are directly prepared on the piezoelectric material substrate by magnetron sputtering technology, resulting in low fault tolerance of the chip. When the design deviates or needs to be adjusted, it will cause huge economic losses and waste of processing cycles. In addition, after the surface acoustic wave microfluidic device is completed, its structure is difficult to modify and can only complete a single function of enrichment, sorting and arrangement. Although some detachable microfluidic chamber settings have appeared in recent years, see the article Povilas, et al. "Dual-wave acoustofluidic centrifuge for ultrafast concentration of nanoparticles and extracellular vesicles." Small 19.35(2023):2300390.

[0004] However, it does not fundamentally open up the freedom of the acoustic tweezers chip, and still needs to be prepared by magnetron sputtering or manual pressing. This not only increases the preparation cost of the chip, but also increases the difficulty of device construction, which greatly hinders the promotion and popularization of surface acoustic wave microfluidic devices. Summary of the invention

[0005] In order to solve the above problems, the present invention proposes a multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device and method. It can realize the detachable control of the multi-parameter structure of the surface acoustic wave microfluidic acoustic tweezers device, realize that the same device can achieve different surface acoustic wave propagation speeds and different surface acoustic wave effects, and the piezoelectric material substrate and flexible interdigital electrodes can be reused, greatly reducing the R&D cost and construction period in the R&D process of the surface acoustic wave microfluidic acoustic tweezers device.

[0006] The technical solution of the present invention is as follows:

[0007] A multi-degree-of-freedom adjustable surface acoustic wave microfluidic acoustic tweezers device comprises a surface acoustic wave generating device, a surface acoustic wave acting device and a multi-dimensional regulating device.

[0008] The surface acoustic wave generating device includes a piezoelectric material substrate and a flexible interdigitated electrode. The piezoelectric material substrate is composed of a transparent piezoelectric material substrate, such as lithium niobate, zinc oxide, etc., wherein lithium niobate has anisotropy, so the propagation speed on different crystal phases is different, which also brings different experimental results. The flexible interdigitated electrode refers to a polyimide or polyethylene terephthalate substrate interdigitated electrode. The period of the finger spacing of the flexible interdigitated electrode is the same as the wavelength of the surface acoustic wave. Generally, an interdigitated electrode with a frequency of 20MHz is used, that is, the period of the finger spacing is 200 microns. The finger spacing is determined by the required wavelength and the angle between the flexible interdigitated electrode and the piezoelectric material substrate. The piezoelectric material substrate and the flexible interdigitated electrode are contacted by soft pressing.

[0009] The surface acoustic wave action device adopts a PDMS micro-ring or a PDMS micro-channel.

[0010] The PDMS microring is prepared by dipping a metal circular blade into a solution of PDMS basic components and a curing agent mixed in a ratio of 10:1, and drying it at 80°C. The PDMS microchannel is prepared by pouring a solution of PDMS basic components and a curing agent mixed in a ratio of 10:1 into a mold, drying it, and demolding it.

[0011] The PDMS micro-rings and PDMS micro-channels are selected for use according to functional requirements, and the connection method between them and the piezoelectric material substrate can be selected by plasma bonding process or photosensitive adhesive bonding method.

[0012] The multi-dimensional adjustment device includes a front and rear adjustment knob, a horizontal adjustment knob, a vertical adjustment knob, a circular motion track, a through hole, a circular motion track connector, a PMMA hard plate and a PDMS sheet. The front and rear adjustment knob, the horizontal adjustment knob and the vertical adjustment knob are driven by a small gear set, and their motion accuracy is in the micron level. The circular motion track is concentric with the piezoelectric material substrate in the center. The through hole is convenient for using an inverted fluorescence microscope to observe the micro-nano particle manipulation effect of the chip. The circular motion track connector and the circular motion track can cooperate to achieve low sliding resistance movement. The PMMA hard plate can evenly transmit pressure downward to the PDMS sheet and the flexible fork finger electrode, so that the flexible fork finger electrode and the piezoelectric material substrate fit tightly. The PDMS sheet is softly connected to the flexible fork finger electrode to prevent the pressure from increasing too fast and causing damage to the piezoelectric material substrate.

[0013] A method for using a multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device for rapid visualization and enrichment of low-abundance micro-nanoscale particles, comprising the following steps:

[0014] The first step: first adjust the front and rear adjustment knobs, the horizontal adjustment knobs and the circular motion track connector in the multi-dimensional adjustment device so that a pair of flexible interdigital electrodes are placed opposite each other in an alternating manner and the edges of the front ends of the flexible interdigital electrodes remain parallel.

[0015] Step 2: Turn the vertical adjustment knob to make the flexible interdigital electrode fit tightly against the piezoelectric material substrate.

[0016] Step 3: Select a suitable PDMS microring according to the staggered spacing of a pair of flexible interdigital electrodes. The staggered spacing of general micron-sized particles is 3mm, and the diameter of the PDMS microring is 10mm. Dip the PDMS microring evenly in photosensitive glue and place it in the center of a pair of flexible interdigital electrodes, and then place the device under a UV lamp for baking for 30 minutes.

[0017] Step 4: Add the target solution into the PDMS microring through a pipette, pass a radio frequency signal of the resonant frequency into the flexible interdigital electrode, and increase the input power to between 20dBm-25dBm.

[0018] Step 5: Place the device on an inverted fluorescence microscope and observe the particle enrichment state in the PDMS microring through the through-hole. After enrichment, use a pipette to visually extract the particles in the central enriched area.

[0019] A method for using a multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device for patterned arrangement and manipulation of micro-nanoscale particles, comprising the following steps:

[0020] Step 1: First adjust the front and rear adjustment knobs, horizontal adjustment knobs and circular motion track connector in the multi-dimensional adjustment device so that a pair of flexible interdigital electrodes are placed opposite each other without any misalignment, and the front edges of the flexible interdigital electrodes remain parallel.

[0021] Step 2: Turn the vertical adjustment knob to make the flexible interdigital electrode fit tightly against the piezoelectric material substrate.

[0022] Step 3: Select a suitable PDMS microchannel according to the spacing between a pair of flexible interdigital electrodes and the size of the manipulated particles. The diameter of the microchannel is generally between 10-100 microns, which is about 10 times the size of the manipulated particles. The PDMS microchannel is bonded to the piezoelectric material substrate through a plasma bonding process, keeping the distance between the two sides of the microchannel and the two ends of the flexible interdigital electrodes the same.

[0023] Step 4: Inject the target solution into the PDMS microchannel through a syringe pump, pass a radio frequency signal of a resonant frequency into the flexible interdigital electrode, and increase the input power to between 20dBm and 30dBm.

[0024] Step 5: Place the device on an inverted fluorescence microscope and observe the patterned arrangement of particles in the PDMS microchannel through the through-holes.

[0025] Compared with the prior art, the present invention has the following significant advantages:

[0026] (1) Compared with the existing detachable surface acoustic wave devices, the present invention can perform multi-parameter control on the relative position, misalignment and position relative to the crystal phase of the interdigital electrodes with respect to the piezoelectric material substrate through a multi-dimensional adjustment device.

[0027] (2) Compared with the traditional centrifuge, the enrichment effect of the present invention is also visualized. The enrichment process and effect can be observed in real time through a microscope, and the enriched area can be manually extracted by a handheld pipette. It is also easier to integrate with analytical research equipment for research and development.

[0028] (3) Compared with a detachable device that separates the surface acoustic wave excitation module from the action module, the present invention achieves efficient surface acoustic wave propagation by regulating the position of the interdigital electrodes on the same piezoelectric material substrate, thereby reducing the acoustic wave coupling loss between different materials.

[0029] (4) The present invention achieves real-time monitoring during the device assembly process by introducing a multi-sensor module, including the contact pressure between the flexible interdigital electrodes and the piezoelectric material substrate, thereby avoiding damage to the piezoelectric material substrate caused by excessive pressure during the assembly process. At the same time, the temperature controller introduced can monitor the heating effect of the surface acoustic wave device on the target liquid in real time, thereby improving the biocompatibility during the action of the sound wave and reducing the unpredictable impact of excessive heat generation on the vitality and activity of the target biological particles. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure of a multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device;

[0031] Figure 2 A schematic diagram of the structure explosion of a multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device;

[0032] Figure 3 This is a diagram showing the effect of enrichment experiment of 1 micron particles by using this device;

[0033] Figure 4 The structural principle diagram of the device to achieve micro-nanoparticle enrichment and manipulation;

[0034] Figure 5 This is the effect diagram of patterning 5-micron particles using this device;

[0035] Figure 6 This is a schematic diagram of the structure for realizing patterned manipulation of micro-nanoparticles through this device. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of this application.

[0037] Example 1

[0038] Please refer to Figure 4 , Figure 4 The schematic diagram of the structure of a multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device for micro-nanoparticle enrichment and manipulation of the present invention. Two flexible forked-finger electrodes are placed opposite each other with a 3mm offset, and the offset distance can be determined according to the droplet diameter. The droplet diameter needs to be larger than the offset distance so that the staggered surface acoustic waves can act on the droplets. Drop 50 microliters of droplets containing 1 micron fluorescent particles in the central area and turn on the signal. The resonant frequency of the flexible forked-finger electrodes is detected by a vector network analyzer to determine the resonant frequency. The effective input of the signal after passing through the amplifier is 20dBm. Finally, the micro-nanoparticles in the droplets are rapidly and visually enriched under the action of the facing surface acoustic waves, as shown in the effect diagram. Figure 3 It can realize the rapid pretreatment of target samples and be used in the research of cutting-edge fields such as drug analysis and pathogen detection.

[0039] Example 2

[0040] Please refer to Figure 6 , Figure 6 The following is a schematic diagram of the structure of a multi-degree-of-freedom adjustable surface acoustic wave microfluidic acoustic tweezers device for patterned manipulation of micro-nanoparticles of the present invention. Two flexible forked electrodes are placed opposite each other, which will form a standing wave in the center area. The resonant frequency of the chip is tested using the above method, and a signal with a power of not less than 20dBm is added. A square PMDS liquid dish is added to the center area to hold the liquid, and 300 microliters of liquid are added. Finally, the 50-micron particles in the liquid are arranged in a fast and visual pattern under the action of the surface acoustic standing wave, and the effect is shown in the figure. Figure 5 It can realize the research in cutting-edge fields such as tissue engineering such as bone cell molding.

[0041] Example 3

[0042] A multi-degree-of-freedom adjustable surface acoustic wave microfluidic acoustic tweezers device comprises a surface acoustic wave generating device, a surface acoustic wave acting device and a multi-dimensional regulating device.

[0043] The surface acoustic wave generating device includes a piezoelectric material substrate 5 and a flexible interdigitated electrode 6. The piezoelectric material substrate 5 is composed of a transparent piezoelectric material substrate, such as lithium niobate, zinc oxide, etc., wherein lithium niobate has anisotropy, so the propagation speed on different crystal phases is different, which also brings different experimental results. The flexible interdigitated electrode 6 refers to a polyimide PI or polyethylene terephthalate PET substrate interdigitated electrode. The period of the finger spacing of the flexible interdigitated electrode 6 is the same as the wavelength of the surface acoustic wave. Generally, an interdigitated electrode with a frequency of 20MHz is used, that is, the period of the finger spacing is 200 microns. The finger spacing is determined by the required wavelength and the angle between the flexible interdigitated electrode 6 and the piezoelectric material substrate 5. The piezoelectric material substrate 5 and the flexible interdigitated electrode 6 are in contact by soft pressing.

[0044] The surface acoustic wave action device adopts a PDMS micro-ring 11 or a PDMS micro-channel 12 .

[0045] The PDMS microring 11 is prepared by dipping a metal circular blade into a solution of PDMS basic components and a curing agent mixed in a ratio of 10:1, and drying it at 80° C. The PDMS microchannel 12 is prepared by pouring a solution of PDMS basic components and a curing agent mixed in a ratio of 10:1 into a mold, drying it, and demolding it.

[0046] The PDMS micro-ring 11 and the PDMS micro-channel 12 are selected for use according to functional requirements, and the connection method between them and the piezoelectric material substrate 5 can be selected by plasma bonding process or photosensitive adhesive bonding method.

[0047] The multi-dimensional adjustment device includes a front and rear adjustment knob 1, a horizontal adjustment knob 2, a vertical adjustment knob 3, a circular motion track 4, a through hole 7, a circular motion track connector 8, a PMMA hard plate 9 and a PDMS sheet 10. The front and rear adjustment knob 1, the horizontal adjustment knob 2 and the vertical adjustment knob 3 are driven by a small gear set, and their motion accuracy is in the micron level. The circular motion track 4 is concentric with the piezoelectric material substrate 5 at the center. The through hole 7 is convenient for using an inverted fluorescence microscope to observe the micro-nano particle manipulation effect of the chip. The circular motion track connector 8 and the circular motion track 4 can cooperate to achieve low sliding resistance movement. The PMMA hard plate 9 can evenly transmit pressure downward to the PDMS sheet 10 and the flexible interdigital electrode 6, so that the flexible interdigital electrode 6 and the piezoelectric material substrate 5 are tightly fitted. The PDMS sheet 10 is softly connected to the flexible interdigital electrode 6 to prevent the pressure from increasing too fast and causing damage to the piezoelectric material substrate 5.

[0048] Example 4

[0049] A method for using a multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device for rapid visualization and enrichment of low-abundance micro-nanoscale particles, comprising the following steps:

[0050] The first step: first adjust the front and rear adjustment knobs 1, the horizontal adjustment knobs 2 and the circular motion track connector 8 in the multi-dimensional adjustment device so that a pair of flexible interdigital electrodes 6 are placed opposite each other in an alternating manner and the front edges of the flexible interdigital electrodes 6 remain parallel.

[0051] Step 2: Turn the vertical adjustment knob 3 to make the flexible interdigital electrode 6 fit tightly with the piezoelectric material substrate 5.

[0052] Step 3: Select a suitable PDMS microring 11 according to the staggered spacing of a pair of flexible interdigital electrodes 6. The staggered spacing of general micron-sized particles is 3 mm, and the diameter of the PDMS microring 11 is 10 mm. Evenly dip the PDMS microring 11 in photosensitive glue and place it in the center of a pair of flexible interdigital electrodes 6, and then place the device under a UV lamp for baking for 30 minutes.

[0053] Step 4: Add the target solution into the PDMS microring 11 through a pipette, and introduce a radio frequency signal of a resonant frequency into the flexible interdigital electrodes to increase the input power to between 20 dBm and 25 dBm.

[0054] Step 5: Place the device on an inverted fluorescence microscope, observe the particle enrichment state in the PDMS microring 11 through the through hole 7, and after enrichment, visually extract the particles in the central enrichment area through a pipette.

[0055] Example 5

[0056] A method for using a multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device for patterned arrangement and manipulation of micro-nanoscale particles, comprising the following steps:

[0057] The first step: first adjust the front and rear adjustment knobs 1, the horizontal adjustment knobs 2 and the circular motion track connector 8 in the multi-dimensional adjustment device so that a pair of flexible interdigital electrodes 6 are placed opposite each other without any misalignment, and the front edges of the flexible interdigital electrodes 6 remain parallel.

[0058] Step 2: Turn the vertical adjustment knob 3 to make the flexible interdigital electrode 6 fit tightly with the piezoelectric material substrate 5.

[0059] Step 3: Select a suitable PDMS microchannel 12 according to the spacing between a pair of flexible interdigital electrodes 6 and the scale of the manipulated particles. The diameter of the PDMS microring 11 is 100 mm. The PDMS microchannel 12 is bonded to the piezoelectric material substrate 5 through a plasma bonding process, keeping the distance between the two sides of the microchannel and the two ends of the flexible interdigital electrodes the same.

[0060] Step 4: Inject the target solution into the PDMS microchannel 12 through a syringe pump, and pass a radio frequency signal of a resonant frequency into the flexible interdigital electrodes to increase the input power to between 20 dBm and 30 dBm.

[0061] Step 5: Place the device on an inverted fluorescence microscope and observe the patterned arrangement state of the particles in the PDMS microchannel 12 through the through hole 7.

Claims

1. A multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device, characterized in that: It includes a surface acoustic wave generating device, a surface acoustic wave acting device, and a multi-dimensional regulating device; The surface acoustic wave generating device comprises a piezoelectric material substrate (5) and a flexible interdigitated electrode (6); the piezoelectric material substrate (5) is a transparent piezoelectric material substrate; the flexible interdigitated electrode (6) is a polyimide (PI) or polyethylene terephthalate (PET) substrate interdigitated electrode; the period of the interdigitated distance of the flexible interdigitated electrode (6) is the same as the wavelength of the surface acoustic wave; The surface acoustic wave action device adopts a PDMS microring (11) or a PDMS microchannel (12); The PDMS microring (11) is prepared by dipping a metal circular blade into a solution obtained by mixing the PDMS basic components and the curing agent in a ratio of 10:1, and drying the solution; the PDMS microchannel (12) is prepared by pouring a solution obtained by mixing the PDMS basic components and the curing agent in a ratio of 10:1 into a mold, drying the solution, and demoulding the mold; The multi-dimensional adjustment device comprises a front-to-back adjustment screw (1), a horizontal adjustment screw (2), a vertical adjustment screw (3), a circular motion track (4), a circular motion track connector (8), a PMMA hard plate (9) and a PDMS sheet (10); the front-to-back adjustment screw (1), the horizontal adjustment screw (2) and the vertical adjustment screw (3) are driven by a small gear set, and the motion accuracy is in the micron level; the circular motion track (4) is a concentric circle with the central piezoelectric material substrate (5); the circular motion track connector (8) cooperates with the circular motion track (4) to achieve low sliding resistance motion; the PMMA hard plate (9) uniformly transmits pressure downward to the PDMS sheet (10) and the flexible interdigital electrode (6), so that the flexible interdigital electrode (6) and the piezoelectric material substrate (5) are tightly fitted; the PDMS sheet (10) is softly connected to the flexible interdigital electrode (6).

2. A multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device as claimed in claim 1, characterized in that: The flexible interdigital electrode (6) uses an interdigital electrode with a frequency of 20 MHz, that is, the period of the interdigital spacing is 200 microns, and the interdigital spacing is determined by the required wavelength and the angle between the flexible interdigital electrode (6) and the piezoelectric material substrate (5).

3. A multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device as claimed in claim 1 or 2, characterized in that: The piezoelectric material substrate (5) is made of lithium niobate and zinc oxide.

4. A multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device as claimed in claim 1 or 2, characterized in that: The PDMS micro-ring (11) and the PDMS micro-channel (12) are selected for use according to functional requirements, and the connection method between the PDMS micro-ring (11) and the PDMS micro-channel (12) and the piezoelectric material substrate (5) is selected by plasma bonding process or photosensitive adhesive bonding method.

5. The multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device according to claim 3, characterized in that: The PDMS micro-ring (11) and the PDMS micro-channel (12) are selected for use according to functional requirements, and the connection method between the PDMS micro-ring (11) and the PDMS micro-channel (12) and the piezoelectric material substrate (5) is selected by plasma bonding process or photosensitive adhesive bonding method.

6. A method for using a multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device for rapid visualization and enrichment of low-abundance micro-nanoscale particles, characterized in that: The following steps are involved: The first step is to adjust the front and rear adjustment knobs (1), the horizontal adjustment knobs (2) and the circular motion track connector (8) in the multi-dimensional adjustment device so that a pair of flexible interdigital electrodes (6) are placed in an alternating manner and opposite to each other, and the edges of the front ends of the flexible interdigital electrodes (6) are kept parallel; Step 2: Turn the vertical adjustment screw (3) to make the flexible interdigitated electrodes (6) fit tightly with the piezoelectric material substrate (5); Step 3: Select a PDMS micro-ring (11) according to the staggered spacing of a pair of flexible interdigital electrodes (6), evenly dip the PDMS micro-ring (11) into photosensitive adhesive and place it in the center of the pair of flexible interdigital electrodes (6), and then place the device under a UV lamp for baking; Step 4: Add the target solution into the PDMS microring (11) through a pipette, pass a radio frequency signal of a resonant frequency into the flexible interdigital electrode, and increase the input power to between 20 dBm and 25 dBm; Step 5: Place the device on an inverted fluorescence microscope, observe the particle enrichment state in the PDMS microring (11) through the through hole (7), and after enrichment, visually extract the particles in the central enrichment area using a pipette.

7. The method for using the multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device according to claim 6, characterized in that: In the third step, the staggered spacing is 3 mm, and the diameter of the PDMS micro-ring (11) is 10 mm.

8. A method for using a multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device for patterned arrangement and manipulation of micro-nanoscale particles, characterized in that: The following steps are involved: The first step is to adjust the front and rear adjustment knobs (1), the horizontal adjustment knobs (2) and the circular motion track connector (8) in the multi-dimensional adjustment device so that a pair of flexible interdigital electrodes (6) are placed opposite to each other without any misalignment, and the edges of the front ends of the flexible interdigital electrodes (6) are kept parallel; Step 2: Turn the vertical adjustment screw (3) to make the flexible interdigitated electrodes (6) fit tightly with the piezoelectric material substrate (5); Step 3: Select a PDMS microchannel (12) according to the spacing between a pair of flexible interdigital electrodes (6) and the size of the manipulated particles, and bond the PDMS microchannel (12) to the piezoelectric material substrate (5) through a plasma bonding process, keeping the distances between the two sides of the microchannel and the two ends of the flexible interdigital electrodes the same; Step 4: inject the target solution into the PDMS microchannel (12) through a syringe pump, pass a radio frequency signal of a resonant frequency into the flexible interdigital electrodes, and increase the input power to between 20 dBm and 30 dBm; Step 5: Place the device on an inverted fluorescence microscope and observe the patterned arrangement state of particles in the PDMS microchannel (12) through the through hole (7).

9. The method for using the multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device according to claim 8, characterized in that: In the third step, the diameter of the PDMS microchannel (12) is between 10 and 100 micrometers.

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