Active high-sensitivity Raman substrate enrichment device based on surface acoustic wave and preparation method

Abstract

The invention discloses an enrichment device of an active high-sensitivity Raman substrate based on surface acoustic waves and a preparation method, and belongs to the technical field of surface enhanced Raman detection. The device adopted by the method comprises a heating module and an enrichment module. And the heating module controls the temperature change, so that chip breakage caused by overheating is avoided. In the enrichment module, when an alternating electric signal is applied, an interdigital electrode excites the surface of the chip to generate surface acoustic waves, and then vibration of solid particles is triggered, so that target particles move along the surface of the substrate and are enriched. Meanwhile, the device adopts a portable hydrophobic film, so that the device is convenient to paste and extract, particles in the liquid drops are gathered, and the enrichment speed and the drying efficiency of the particles are remarkably improved. The method is simple and convenient to operate, and provides enrichment and drying treatment for subsequent target particles: to-be-detected particles or molecules are concentrated to a specific area, so that the detection sensitivity of the to-be-detected particles or molecules in Raman spectrum analysis is remarkably improved; and a solution in a liquid sample can be quickly evaporated into solid residues, so that further analysis is facilitated.

Description

Technical Field

[0001] The present invention relates to the field of surface acoustic wave devices and surface enhanced Raman detection, and specifically to an active high-sensitivity Raman substrate enrichment device and preparation method based on surface acoustic wave. The invention aims to achieve efficient enrichment and drying of trace target particles through innovative design, so as to improve the sensitivity and efficiency of Raman spectroscopy detection. Background Art

[0002] At present, the demand for trace substance analysis in scientific research and industrial detection is growing. How to quickly and efficiently achieve the enrichment and detection of trace particles has become a key challenge. Traditional Raman spectroscopy detection faces problems such as insufficient sensitivity and uneven sample distribution when dealing with trace samples, which greatly limits the widespread promotion and use of Raman spectroscopy in practical applications. In particular, the "coffee ring effect" that often occurs during the drying process of droplets further weakens the accuracy and repeatability of the detection results. With its unique advantages in microscale particle manipulation and droplet dynamics regulation, surface wave technology generates vibrations through interdigital transducers, forms waves propagating in a specific direction on the surface of the substrate, and accurately manipulates the target particles in the droplets. By reasonably designing the amplitude and frequency of the surface acoustic wave, it is not only possible to suppress the formation of coffee rings during the drying process of droplets, but also to effectively concentrate the dispersed trace particles in a specific area. Combining SERS with surface acoustic wave enrichment technology can further enhance the detection signal of trace substances and significantly improve the sensitivity and accuracy of Raman spectroscopy detection. The device can not only achieve efficient separation and enrichment of target particles, but also provide uniform solid samples for subsequent Raman spectroscopy detection by accurately enriching and rapidly drying particles in droplets through a surface acoustic wave drive. This device can significantly improve the detection efficiency of trace particles and expand the application prospects of Raman spectroscopy in chemical analysis, biological detection, environmental monitoring and other fields, providing advanced technical support and innovative solutions for high-precision rapid detection. Summary of the invention

[0003] In order to solve the problems existing in the prior art, the present invention provides an active high-sensitivity Raman substrate preparation method based on surface acoustic wave, which aims to achieve efficient enrichment and drying of trace particles through surface acoustic wave technology, and significantly improve the sensitivity and accuracy of Raman spectroscopy detection. It has a simple design and efficient operation, and is suitable for a variety of high-precision trace sample detection fields.

[0004] The technical solution adopted by the present invention is: an active high-sensitivity Raman substrate enrichment device based on surface acoustic wave, the device includes an aluminum plate, a temperature sensor, an enrichment module and a heating module;

[0005] The enrichment module includes a radio frequency line, a circuit board, a piezoelectric substrate, a transducer electrode, and a hydrophobic film; the circuit board and the radio frequency line are detachably welded through a round hole, and the circuit board and the transducer electrode are detachably connected through a spring pin; the transducer electrode and the piezoelectric substrate are connected through a wire bonding technology, and the hydrophobic film and the piezoelectric substrate are detachably attached; the piezoelectric substrate is arranged in a groove of the aluminum plate;

[0006] The hydrophobic film includes an enrichment area and a handle area, wherein the enrichment area is attached to the piezoelectric substrate and is located between two transducer electrodes; the handle area is placed on the outside of the piezoelectric substrate and is used to separate the hydrophobic film from the piezoelectric substrate during pulling; a 128° YX tangential lithium niobate crystal is arranged on the piezoelectric substrate, and a surface acoustic wave is generated through the inverse piezoelectric effect, so that the surface acoustic wave propagates on it, driving the droplets to gather in the enrichment area at the center of the hydrophobic film;

[0007] The heating module comprises a heating plate and a heat sink; the bottom surface of the heating plate is bonded to the heat sink, and the top surface of the heating plate is bonded to the aluminum plate;

[0008] The circuit board is connected to the aluminum plate by screws, and a temperature sensor is arranged on the aluminum plate.

[0009] The four corners of the circuit board are respectively provided with a spherical column, and the height of the spherical column is greater than the height of the heat sink.

[0010] A cross-shaped groove is arranged in the aluminum plate, and the length and width of the cross-shaped groove are the same as those of the piezoelectric substrate; a circular through groove is arranged inside the cross-shaped groove for microscope light alignment; a cylindrical groove is arranged inside the cross-shaped groove for embedding a temperature sensor.

[0011] The temperature sensor is composed of a cylinder and a hemispherical shape, the spherical surface is tangent to the lower bottom surface of the piezoelectric substrate, and the other surfaces are embedded in the aluminum plate. The hemispherical part is the temperature measuring part.

[0012] The transducer electrode is a ladder-shaped metal pattern, and the electrode is connected to the circuit board through a spring pin.

[0013] A method for preparing an active high-sensitivity Raman substrate based on surface acoustic wave, using the above device, specifically comprises the following steps:

[0014] S1, attach the hydrophobic film to the piezoelectric substrate and add droplets to the enriched area;

[0015] S2. Connect the RF ports at both ends of the device to the output end of the signal generator, and the signal generator outputs electrical energy to the piezoelectric substrate through the transducer electrodes.

[0016] S3, the electrical energy is converted into surface acoustic waves through the piezoelectric substrate, and the surface acoustic waves propagate on it, driving the droplets to gather in the enriched area in the center of the hydrophobic film;

[0017] S4. When the sample reaches the enrichment effect, the heating plate heats up, the sample dries quickly, and the temperature and heat dissipation are monitored in real time to prevent damage to the device and the sample.

[0018] S5. Pull up the handle area of ​​the hydrophobic film to separate the enriched area of ​​the hydrophobic film from the piezoelectric substrate, and place the hydrophobic film on a glass slide to obtain a Raman substrate for Raman detection.

[0019] The invention relates to a high-sensitivity Raman spectrum rapid detection device for surface acoustic wave enriched dry droplets, which comprises a heating plate, a heat sink, an aluminum plate, a temperature sensor, a transducer electrode, a hydrophobic film, a spring pin and a circuit board.

[0020] The device shell is composed of two parts: a heating plate and an aluminum plate which can be matched and separated from each other.

[0021] A heat sink is specifically provided under the heating plate to achieve a heat dissipation function and provide protection for the chip device.

[0022] The aluminum plate is penetrated in the center of the corresponding rectangular chip area to form a circular hole, so that light can pass through the circular hole, pass through the heating plate and the hydrophobic layer area of ​​the chip in turn, and finally enter the microscope.

[0023] Specifically, a rectangular groove is provided in the center of the aluminum plate for placing a piezoelectric substrate integrated with an interdigital transducer and a metal particle enrichment device, and a through groove is provided in the center of the rectangular groove for real-time observation of the metal particle enrichment status and for observing the hydrophobic angle and morphological changes of the droplets.

[0024] The interdigital transducer module is composed of three parts: a piezoelectric material substrate, interdigital electrodes and a PDMS portable hydrophobic film.

[0025] A specific piezoelectric material substrate, wherein the piezoelectric material substrate includes a 128° YX-tangential lithium niobate crystal, which is used to generate surface acoustic waves through the inverse piezoelectric effect, so that the surface acoustic waves propagate thereon, driving the droplets in the enrichment device to gather toward the center of the PDMS portable hydrophobic film.

[0026] The transducer module is composed of a chip and two pairs of interdigital electrodes. The interdigital electrodes form a metal pattern on the surface of the chip, arranged relative to each other and spaced a certain distance apart. The interdigital electrodes are connected to a circuit board through spring pins.

[0027] The specific pattern of the interdigitated electrodes is prepared on the surface of the piezoelectric substrate by photolithography. The specific chip is usually made of piezoelectric materials. Piezoelectric materials have a piezoelectric effect and can convert electrical energy into mechanical energy (or sound waves). In surface acoustic wave technology, piezoelectric materials are deformed by applying an electric field, thereby generating surface acoustic waves, which are used to drive the movement of particles or molecules in the liquid to achieve the purpose of enriching or manipulating the target substance.

[0028] The specific piezoelectric material composition is lithium niobate (LiNbO3), which is a very common piezoelectric material with good piezoelectric properties and stability, and is widely used in surface acoustic wave devices.

[0029] The two parts on the top are circuit boards. The circuit boards are fixed to the aluminum plate with screws and are used to connect the electrical signal input terminals and other signal processing devices. The small holes on the circuit boards facilitate the fixing of the cover with screws to ensure a stable connection of the circuit boards.

[0030] The screw is T-shaped, the circuit board has four T-shaped areas embedded in it that directly pass through the aluminum plate groove, the aluminum plate groove has four cylindrical threaded areas embedded in it, and the circuit board and the aluminum plate can be fixed by screws and threads.

[0031] The hydrophobic film is formed by connecting a large circle and two small circles. The large circle portion is the enrichment area, and the small circle portion and the connection area form a handle, which can be used as a handle for easy disassembly or as a label for easy recording of samples.

[0032] The aluminum plate has an intentional cross-shaped groove in it, the length and width of the long part of the cross-shaped groove are the same as those of the piezoelectric material, which is convenient for placement; there is a circular through groove inside the groove for microscope light alignment; there is a small cylindrical groove inside the groove, the diameter and height of which are the same as those of the temperature sensor, which is convenient for embedding.

[0033] The design of the device shows a modular structure, and the various parts can be assembled and disassembled by screws, which is convenient for maintenance and replacement of components. The combination of aluminum plate and heat sink ensures stable operation of the device during heating, while the circular hole design adapts to the needs of optical or microscopic observation.

[0034] The method in this application is compared with the previous natural drip method and the Raman substrate preparation method based on super-hydrophobic materials. The natural drip method will produce coffee rings, which will cause random hot spots to make the Raman quantitative detection effect worse, and the ability to detect low abundance of target objects is low. The problem with the Raman substrate preparation method of super-hydrophobic materials is that the preparation method of super-hydrophobic materials is difficult, and the process stability is poor, making the performance of the material prepared each time unstable.

[0035] Compared with the prior art, the present invention has the following significant advantages:

[0036] (1) Active enrichment: By driving the interdigital transducer to generate surface acoustic waves, it can efficiently and accurately gather trace target particles to the specified area, significantly suppressing the formation of the coffee ring effect, thereby improving the accuracy and reliability of detection;

[0037] (2) Rapid preparation of Raman substrate: The vibration characteristics of surface acoustic waves can accelerate the drying process of droplets. At the same time, the hydrophobic film increases the hydrophobic angle and improves the enrichment efficiency. This is very beneficial for biological analysis and other scientific research applications that require rapid processing;

[0038] (3) Reduce random hot spot distribution: quickly enrich the target particles to form uniform nanoclusters, ensure the random uniformity of Raman spectroscopy detection, and achieve high-sensitivity detection;

[0039] (4) Portable and easy to integrate: The detachable and modular design of the shell structure makes the device easy to maintain and clean, and also facilitates the replacement of key components or technical upgrades.

[0040] The enrichment module is equipped with a set of interdigital electrodes. When an alternating electrical signal is applied, the interdigital electrodes excite the chip surface to generate surface acoustic waves, which in turn induce the vibration of solid particles, causing the target particles to move along the substrate surface and be enriched. This method integrates particle separation, sample pretreatment and high-sensitivity detection functions, and has the potential for efficient and convenient laboratory applications, especially in the fields of chemical analysis, biomedical testing, environmental monitoring and food safety testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings are intended to provide a further understanding of the present invention, and the accompanying drawings are incorporated into the specification and constitute a part of the specification. In order to clearly explain the technical solutions in the embodiments of the present invention or the prior art, the following briefly describes the accompanying drawings required for describing the embodiments or the prior art.

[0042] Figure 1 An exploded diagram of the structure of a high-sensitivity Raman spectroscopy rapid detection device for surface acoustic wave enriched dry droplets provided in an embodiment of the present invention;

[0043] Figure 2 A structural diagram of a high-sensitivity Raman spectroscopy rapid detection device for surface acoustic wave enriched dry droplets provided in an embodiment of the present invention;

[0044] Figure 3 A schematic diagram of measuring the hydrophobic angle of a droplet provided in an embodiment of the present invention;

[0045] Figure 4 Raman detection diagrams of enriched and unenriched 4-MBA provided in the embodiments of the present invention;

[0046] Figure 5This is a comparison between this method and the natural drying of traditional Raman substrate droplets.

[0047] The symbols in the figure are as follows: 1. RF port, 2. screw, 3. circuit board, 4. spring pin, 5. hydrophobic film, 5a. enrichment area, 5b. handle area, 6. droplet, 7. transducer electrode, 8. piezoelectric substrate, 9. temperature sensor, 10. aluminum plate, 11. heating plate, 12. heat sink. DETAILED DESCRIPTION

[0048] 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.

[0049] Please refer to Figure 1 The structural explosion diagram of the high-sensitivity Raman spectroscopy rapid detection device for surface acoustic wave enrichment of dry droplets provided in an embodiment of the present invention includes an aluminum plate, a temperature sensor, an enrichment module and a heating module.

[0050] Enrichment module: The enrichment module consists of 1 radio frequency line, 3 circuit boards, 8 piezoelectric substrates, 7 transducer electrodes, and 5 hydrophobic films.

[0051] The RF line 1 and the circuit board 3 are detachably welded through the circular hole to ensure good electrical connection. The piezoelectric substrate 8 is connected to the transducer electrode 7 through the wire bonding technology to achieve effective transmission of surface acoustic waves. The hydrophobic film 5 is detachably bonded to the piezoelectric substrate 8. The hydrophobic film is designed to be connected by a large circle-enrichment area 5a and two small circles-handle areas 5b. The large circle part serves as the enrichment area, and the small circle part and the connection area form a handle, which is convenient for disassembling and recording samples.

[0052] The heating module is composed of 11 heating plates and 12 heat sinks.

[0053] The heating plate 11 and the heat sink 12 are detachably bonded by organic silicon high temperature adhesive to ensure stability in a high temperature environment. The heating plate 11 and the aluminum plate 10 are also detachably bonded by organic silicon high temperature adhesive to provide uniform heat distribution.

[0054] Connection between the circuit board and the aluminum plate: The circuit board 3 and the aluminum plate 10 are detachably connected via T-shaped screws 2. Four T-shaped areas are embedded in the circuit board and pass through the aluminum plate grooves. Four cylindrical threaded areas are embedded in the aluminum plate grooves so as to be fixed by screws and threads.

[0055] The four corners of the circuit board 3 are respectively provided with a spherical column, and the height of the column is greater than the height of the heat sink, so as to facilitate supporting the whole device.

[0056] A cross-shaped groove is provided in the aluminum plate 10, and the length and width of the long part of the cross-shaped groove are the same as those of the piezoelectric substrate 8, which is convenient for placement; there is a circular through groove inside the cross-shaped groove for microscope alignment; there is a small cylindrical groove inside the cross-shaped groove, and the diameter and height are the same as those of the temperature sensor, which is convenient for embedding.

[0057] Design of temperature sensor: The temperature sensor 9 is composed of a cylindrical and a hemispherical shape. The spherical surface is tangent to the bottom surface of the piezoelectric material, and the other surfaces are embedded in the aluminum plate 10. The spherical part is used for temperature measurement to ensure the accuracy of temperature measurement.

[0058] The screw is T-shaped, and four T-shaped areas are embedded in the circuit board 3 and directly pass through the aluminum plate groove. The groove of the aluminum plate 10 is embedded with four cylindrical threaded areas. The circuit board 3 and the aluminum plate 10 can be fixed by screws and threads.

[0059] The transducer electrode is a ladder-shaped metal pattern, and the electrode is connected to the circuit board 3 through the spring pin 4.

[0060] Please refer to Figure 2 This is a structural diagram of a high-sensitivity Raman spectroscopy rapid detection device for surface acoustic wave enriched dry droplets. Figure 1 Four parts including aluminum plate, temperature sensor, enrichment device, and heating device were assembled.

[0061] Please refer to Figure 3 , by using a contact angle tester, 2.5 microliters of solution was accurately dropped onto the surface of the hydrophobic film. The groove design on the aluminum plate makes it easier to observe the hydrophobic angle, and the measured contact angle reaches 109°. This optimized angle further improves the enrichment effect of target particles in the droplets, thus laying a good foundation for subsequent high-sensitivity detection.

[0062] Method and steps for using the above device:

[0063] Use a metal mold cutting blade to cut out a handle-type PDMS mold and spread it flat in the center area of ​​the acoustic tweezers device to avoid bubbles. Adjust the signal generator to the operating frequency and voltage range of the acoustic tweezers device to ensure that the operating power of the acoustic tweezers device is 20-23dBm. After turning on the signal, drip a suitable volume of droplets containing metal nanoparticles (3-10 microliters is best) into the center area of ​​PDMS. The particle size of the metal nanoparticles can be above 50nm. During the operation of the acoustic tweezers device, turn on the bottom heating platform to accelerate the volatilization of the droplets. The bottom temperature is best controlled at 60-80℃. After the droplets evaporate, remove the PDMS film and place it on a glass slide to complete the preparation of the highly sensitive Raman substrate material.

[0064] When in use, simply drop the solution containing the target object into the enriched area in the center of the PDMS film. After the sample is naturally dried, send it to a confocal Raman microscope for detection.

[0065] A specific method for preparing an active high-sensitivity Raman substrate based on surface acoustic wave comprises the following steps:

[0066] S1, attach the hydrophobic film 5 to the piezoelectric substrate 8, and drip the liquid drop 6 on the enriched area 5a;

[0067] S2, the RF ports 1 at both ends of the detection device are connected to the output end of the signal generator through the RF line, the signal generator outputs a voltage signal with a certain frequency and amplitude, and the electrical signal is transmitted to the piezoelectric substrate 8 through the transducer electrode 7

[0068] S3, a 128° YX-tangential lithium niobate crystal is disposed on the piezoelectric substrate 8, and a surface acoustic wave is generated by the inverse piezoelectric effect, so that the surface acoustic wave propagates on the crystal, driving the droplets to gather in the enriched area 5a at the center of the hydrophobic film 5;

[0069] S4. Observe the sample in the knife droplet through a microscope to achieve the desired enrichment effect. The temperature can be increased by the heating plate 11 to quickly dry the water in the droplet 6 to obtain the enrichment. The temperature sensor 9 can detect the highest temperature of the device in real time to prevent the high temperature from causing irreversible damage to the piezoelectric substrate 8 and prevent the prepared Raman substrate from losing its function due to the high temperature. When the droplet 6 is observed to be dry, the temperature can be lowered by the heating plate 11. In this process, the heat sink 12 continues to dissipate heat.

[0070] S5, pulling up the handle area 5b of the hydrophobic film 5 to separate the enriched area 5a of the hydrophobic film 5 from the piezoelectric substrate 8, placing the hydrophobic film 5 on a glass slide, and obtaining a Raman substrate for Raman detection.

[0071] Please refer to Figure 4 , using Raman spectroscopy to detect enriched and unenriched gold particle-4-MBA complexes. Experimental data showed that the enriched particles significantly improved the sample uniformity and Raman signal intensity. This enrichment process not only improved the sensitivity of detection, but also effectively enhanced the uniformity of the signal, providing reliable data support for high-sensitivity analysis.

[0072] Figure 5By comparing this method with the natural drying of traditional Raman substrate droplets, it can be seen that the preparation speed of the highly uniform Raman substrate of this method is significantly improved compared with the traditional method. This is due to the fact that part of the energy in the PDMS film will be converted into heat energy during the propagation of the surface acoustic wave, thereby accelerating the formation of the Raman substrate. In addition, due to the surface tension of the droplets in the traditional method, the nanoparticles will form a coffee ring around the droplets, making the distribution of the Raman substrate uneven. This method is based on the active enrichment of nanoparticles by surface acoustic waves, making the distribution of the Raman substrate more compact and forming a nanocluster structure. This is also the fundamental reason why this method amplifies the Raman signal.

[0073] The present invention provides a highly sensitive Raman spectroscopy rapid detection device for enriching and drying droplets based on surface acoustic waves, which has a sophisticated design, convenient operation, efficient particle enrichment ability and excellent detection sensitivity. Compared with traditional detection methods, the present device can significantly improve the enrichment efficiency of trace particles and greatly improve the signal intensity and uniformity of Raman spectra. Driven by surface acoustic waves, the device has little effect on the sample during operation, is particularly suitable for trace samples that require precise detection, and has significant advantages in particle distribution uniformity, detection sensitivity and operational stability. The present invention is suitable for fields such as trace particle detection, environmental monitoring, biomedical testing, etc., especially in high-sensitivity detection scenarios such as trace pathogen enrichment and low-concentration analysis, showing a wide range of application prospects. Although the above is a specific embodiment of the present invention, the protection scope of the present invention is not limited thereto. For those familiar with the art, any changes or substitutions made within the technical scope disclosed by the present invention should be deemed to fall within the protection scope of the present invention.

[0074] Finally, it should be noted that the protection scope of this application is not limited to the applications and technical solutions disclosed in the embodiments. Any technician familiar with the technical field can make appropriate changes and substitutions according to specific application requirements and environmental conditions within the technical scope disclosed in this application. These possible changes and substitutions, including but not limited to the selection of materials, adjustment of structures, expansion of functions, and integration with other technologies, etc., should be regarded as part of the protection scope of this application.

Claims

1. An active high-sensitivity Raman substrate enrichment device based on surface acoustic wave, characterized in that: The device includes an aluminum plate, a temperature sensor, an enrichment module and a heating module; The enrichment module comprises a radio frequency line (1), a circuit board (3), a piezoelectric substrate (8), a transducer electrode (7), and a hydrophobic film (5); the circuit board (3) and the radio frequency line (2) are detachably welded via a circular hole, and the circuit board (3) and the transducer electrode (7) are detachably connected via a spring pin (4); the transducer electrode (7) and the piezoelectric substrate (8) are connected via a wire bonding technique, and the hydrophobic film (5) and the piezoelectric substrate (8) are detachably bonded; the piezoelectric substrate (8) is disposed in a groove of an aluminum plate (10); The hydrophobic film (5) comprises a central enrichment area (5a) and handle areas (5b) on both sides, wherein the enrichment area (5a) is attached to the piezoelectric substrate (8) and is located between two transducer electrodes (7); the handle area (5b) is placed on the outside of the piezoelectric substrate (8) and is used to separate the hydrophobic film (5) from the piezoelectric substrate (8) during pulling; a 128° YX tangential lithium niobate crystal is arranged on the piezoelectric substrate (8) to generate surface acoustic waves through the inverse piezoelectric effect, so that the surface acoustic waves propagate on the crystal, driving the droplets to gather in the central enrichment area (5a) of the hydrophobic film (5); the heating module comprises a heating plate (11) and a heat sink (12); the bottom surface of the heating plate (11) is bonded to the heat sink (12), and the top surface of the heating plate (11) is bonded to the aluminum plate (10); The circuit board (3) is connected to the aluminum plate (10) via screws (2), and a temperature sensor (9) is provided on the aluminum plate (10).

2. The active high-sensitivity Raman substrate enrichment device based on surface acoustic wave according to claim 1, characterized in that: The four corners of the circuit board (3) are respectively provided with a spherical column, and the height of the spherical column is greater than the height of the heat sink.

3. The active high-sensitivity Raman substrate enrichment device based on surface acoustic wave according to claim 1, characterized in that: A cross-shaped groove is provided in the aluminum plate (10), and the length and width of the cross-shaped groove are the same as the length and width of the piezoelectric substrate (8); a circular through groove is provided inside the cross-shaped groove for microscope light alignment; and a cylindrical groove is provided inside the cross-shaped groove for embedding a temperature sensor (9).

4. The active high-sensitivity Raman substrate enrichment device based on surface acoustic wave according to claim 1, characterized in that: The temperature sensor (9) is composed of a cylindrical shape and a hemispherical shape, the spherical surface is tangent to the lower bottom surface of the piezoelectric substrate (8), and the other surfaces are embedded in the aluminum plate (10), and the hemispherical part is the temperature measurement part.

5. According to claim 1, a highly sensitive Raman spectrum rapid detection device for surface acoustic wave-based active high-sensitivity Raman substrate enrichment of dry droplets, characterized in that: The transducer electrode (7) is a ladder-shaped metal pattern, and the electrode is connected to the circuit board (3) via a spring pin (4).

6. A method for preparing an active high-sensitivity Raman substrate based on surface acoustic waves, characterized in that: The device according to any one of claims 1 to 5 comprises the following steps: S1, attaching the hydrophobic film (5) to the piezoelectric substrate (8), and dropping a droplet (6) on the enriched area (5a); S2, connecting the radio frequency ports (1) at both ends of the detection device to the output end of the signal generator through radio frequency lines, the signal generator outputs a voltage signal with a certain frequency and amplitude, and the electrical signal is transmitted to the piezoelectric substrate (8) through the transducer electrode (7); S3, a 128° YX-tangential lithium niobate crystal is arranged on the piezoelectric substrate (8), and a surface acoustic wave is generated by the inverse piezoelectric effect, so that the surface acoustic wave propagates on the piezoelectric substrate, driving the droplets to gather in the enriched area (5a) at the center of the hydrophobic film (5); S4, observing the enrichment effect of the sample in the droplet through a microscope, raising the temperature through a heating plate (11) to quickly dry the water in the droplet (6), and obtaining a Raman substrate enrichment on the hydrophobic film (5); S5, pulling up the handle area (5b) of the hydrophobic film (5) to separate the enriched area (5a) of the hydrophobic film (5) from the piezoelectric substrate (8), placing the hydrophobic film (5) on a glass slide, and obtaining a Raman substrate for Raman detection.

7. The method for preparing an active high-sensitivity Raman substrate based on surface acoustic waves according to claim 6, characterized in that: In step S4, the maximum temperature of the device is detected in real time by a temperature sensor (9); when it is observed that the droplet (6) is dried, the temperature is lowered by a heating plate (11); and during this process, the heat sink (12) continues to dissipate heat.

Images