A multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device and method

Abstract

The present invention proposes a surface acoustic wave microfluidic acoustic tweezers device with adjustable multiple degrees of freedom, which belongs to the field of microfluidic technology. It can realize the dynamic adjustable function of multiple key parameters such as the acoustic wave propagation speed, angle and structure of the microfluidic device. It mainly includes 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 includes a piezoelectric material substrate and a flexible interdigitated electrode. The surface acoustic wave action module is composed of a PDMS microchannel or a PDMS microring, which is mainly determined by the function of the acoustic tweezers device. The multi-dimensional adjustment module can freely adjust the relative position of the flexible interdigitated electrode, as well as its position and angle relative to the piezoelectric material substrate, thereby controlling the propagation speed and action effect of the acoustic wave. The present invention can achieve different microfluidic application requirements through multi-dimensional adjustment of the flexible interdigitated electrode and the piezoelectric material substrate.

Description

Technical Field

[0001] The present invention relates to the fields 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 fields such as biochemical analysis and tissue engineering, microfluidics has become a research hotspot both domestically and internationally. Compared to acoustic tweezers, microfluidics offers greater micro- and nanoparticle manipulation capabilities for cell manipulation. Surface acoustic wave (SAW) microfluidics, by combining ultrasound with microfluidics, utilizes surface acoustic waves or bulk acoustic waves for non-contact, label-free, and highly biocompatible manipulation of target micro- and nanoparticles. This technology holds great promise for applications in biomedicine, environmental testing, and drug screening.

[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 bring 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 cavity 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 requires magnetron sputtering or manual pressing to prepare the acoustic tweezers chip. This not only increases the cost of chip preparation, 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] To address the aforementioned issues, the present invention proposes a multi-degree-of-freedom controllable surface acoustic wave (SAW) microfluidic acoustic tweezers device and method. This device allows for detachable control of the device's multi-parameter structure, enabling the same device to achieve different SAW propagation velocities and effects. Furthermore, the piezoelectric substrate and flexible interdigital electrodes can be reused, significantly reducing the R&D cost and construction time of the SAW microfluidic acoustic tweezers device.

[0006] The technical solutions of the present invention are as follows:

[0007] A multi-degree-of-freedom controllable 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 in contact by soft pressing.

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

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

[0011] PDMS microrings and PDMS microchannels are selected based on functional requirements, and the connection method between them and the piezoelectric material substrate can be a plasma bonding process or a photosensitive adhesive bonding method.

[0012] The multi-dimensional adjustment device includes a front and rear adjustment screw, a horizontal adjustment screw, a vertical adjustment screw, 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 screw, the horizontal adjustment screw and the vertical adjustment screw are driven by a small gear set, and their movement accuracy is at the micron level. The circular motion track and the central piezoelectric material substrate are concentric circles. The through hole is convenient for observing the micro-nanoparticle manipulation effect of the chip using an inverted fluorescence microscope. 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 quickly 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] 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 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 screw to ensure a tight fit between the flexible interdigitated electrode and the piezoelectric material substrate.

[0016] Step 3: Select an appropriate PDMS microring based on the interdigital spacing of the flexible interdigital electrodes. A typical interdigital spacing for micron-sized particles is 3mm, and the diameter of the PDMS microring is 10mm. Dip the PDMS microring evenly in photosensitive adhesive and place it in the center of the flexible interdigital electrodes. Bake the device under UV light 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 and 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 enrichment 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 edges of the front ends of the flexible interdigital electrodes remain parallel.

[0021] Step 2: Turn the vertical adjustment screw to ensure a tight fit between the flexible interdigitated electrode and the piezoelectric material substrate.

[0022] Step 3: Select an appropriate PDMS microchannel based on the spacing between the flexible interdigital electrodes and the size of the manipulated particles. Typically, the microchannel diameter is between 10 and 100 microns, approximately 10 times the size of the manipulated particles. The PDMS microchannel is bonded to the piezoelectric substrate using a plasma bonding process, ensuring that both sides of the microchannel are the same distance from the ends of the flexible interdigital electrodes.

[0023] Step 4: Inject the target solution into the PDMS microchannel through a syringe pump, and pass a radio frequency signal of the resonant frequency into the flexible interdigital electrode to 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 of the interdigital electrodes relative to the piezoelectric material substrate and the crystal phase through a multi-dimensional adjustment device.

[0027] (2) Compared with traditional centrifuges, the enrichment effect of the present invention is also visual. The enrichment process and effect can be observed in real time through a microscope, and the enriched area can be manually extracted with 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 incorporates a multi-sensor module to enable real-time monitoring of the device assembly process, including the contact pressure between the flexible interdigitated electrodes and the piezoelectric substrate, thereby preventing damage to the piezoelectric substrate caused by excessive pressure during assembly. Simultaneously, the temperature controller introduced allows for real-time monitoring of the heating effect of the surface acoustic wave device on the target liquid, thereby improving the biocompatibility of the device during acoustic wave action and reducing the unpredictable effects of excessive heat generation on the vitality and activity of the target biological particles. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The schematic diagram shows the structure of a multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device.

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

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

[0033] Figure 4 The schematic diagram of the structure for realizing the enrichment and manipulation of micro-nanoparticles through this device;

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

[0035] Figure 6 This is a schematic diagram of the structural principle for achieving 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 embodiments described are only part of the embodiments of the present application, not 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 efforts are within the scope of protection of this application.

[0037] Example 1

[0038] Please refer to Figure 4 , Figure 4 This is a structural principle diagram of the multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device for micro-nanoparticle enrichment and manipulation of the present invention. Two flexible interdigitated electrodes are placed opposite each other and produce a 3mm offset. The offset spacing can be determined according to the size of the droplet diameter. The droplet diameter needs to be larger than the offset spacing so that the staggered surface acoustic waves can act on the droplets. A 50-microliter droplet containing 1-micron fluorescent particles is dropped into the central area to turn on the signal. The resonant frequency of the flexible interdigitated 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 achieve rapid pretreatment of target samples and be used in cutting-edge research in drug analysis, pathogen detection, and other fields.

[0039] Example 2

[0040] Please refer to Figure 6 , Figure 6 This is a structural principle diagram of the multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device for patterned manipulation of micro-nanoparticles of the present invention. Two flexible interdigitated electrodes are placed face to face, 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 wave standing wave, and the effect is shown in the figure. Figure 5 It can realize the research of cutting-edge fields such as tissue engineering, such as bone cell molding.

[0041] Example 3

[0042] A multi-degree-of-freedom controllable 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 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 a plasma bonding process or a photosensitive adhesive bonding method.

[0047] The multi-dimensional adjustment device includes a front-to-back 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-to-back adjustment knob 1, the horizontal adjustment knob 2, and the vertical adjustment knob 3 are driven by a small gear set, and their movement accuracy is at the micron level. The circular motion track 4 is concentric with the central piezoelectric material substrate 5. The through-hole 7 facilitates the use of an inverted fluorescence microscope to observe the micro-nanoparticle 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, ensuring a tight fit between the flexible interdigital electrode 6 and the piezoelectric material substrate 5. The PDMS sheet 10 is softly connected to the flexible interdigital electrode 6 to prevent excessive pressure growth from damaging 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] Step 1: 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 screw 3 to make the flexible interdigital electrodes 6 fit tightly against the piezoelectric material substrate 5 .

[0052] Step 3: Select an appropriate PDMS microring 11 based on the interdigital spacing of the flexible interdigital electrodes 6. A typical interdigital spacing for micron-sized particles is 3 mm, and the diameter of the PDMS microring 11 is 10 mm. Dip the PDMS microring 11 evenly in photosensitive adhesive and place it in the center of the flexible interdigital electrodes 6. Then, bake the device under a UV lamp 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 electrode to increase the input power to between 20 dBm and 25 dBm.

[0054] Step 5: Place the device on an inverted fluorescence microscope and observe the particle enrichment state in the PDMS microring 11 through the through-hole 7. After enrichment, visualize the particles in the central enrichment area using 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] Step 1: First adjust the front and rear adjustment knobs 1, horizontal adjustment knobs 2 and 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 screw 3 to make the flexible interdigital electrodes 6 fit tightly against the piezoelectric material substrate 5 .

[0059] Step 3: Select a suitable PDMS microchannel 12 based on 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 introduce 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 of 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 adjustment 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-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-back adjustment screw (1), the horizontal adjustment screw (2) and the vertical adjustment screw (3) are driven by a small gear set, and their motion accuracy is in the micron level; the circular motion track (4) and the central piezoelectric material substrate (5) are concentric circles; 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) and the flexible interdigital electrode (6) are softly connected.

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

3. A multi-degree-of-freedom controllable surface acoustic wave microfluidic acoustic tweezers device according to 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 according to 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 according to any one of claims 1 to 5, for rapid visualization and enrichment of low-abundance micro-nanoscale particles, characterized in that: The following steps are involved: Step 1: 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 in an interlaced and opposite manner, and the edges of the front ends of the flexible interdigital electrodes (6) remain parallel; Step 2: Turn the vertical adjustment screw (3) to make the flexible interdigitated electrode (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) in 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, and pass a radio frequency signal of a resonant frequency into the flexible interdigital electrode to increase the input power to between 20 dBm and 25 dBm; Step 5: Place the device on an inverted fluorescence microscope and observe the particle enrichment state in the PDMS microring (11) through the through hole (7). After enrichment, visualize 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 according to any one of claims 1 to 5 for patterned arrangement and manipulation of micro-nanoscale particles, characterized in that: The following steps are involved: Step 1: 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; Step 2: Turn the vertical adjustment screw (3) to make the flexible interdigitated electrode (6) fit tightly with the piezoelectric material substrate (5); Step 3: Select a PDMS microchannel (12) based on the spacing between a pair of flexible interdigital electrodes (6) and the scale of the manipulated particles, and bond the PDMS microchannel (12) 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; 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 electrode to 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 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 microns.

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