Self-powered, portable and high-throughput SERS biological sensing platform

Abstract

The present invention provides a self-powered, portable and high-throughput SERS biological sensing platform. The platform comprises: a handheld Raman spectrometer, a triboelectric nanogenerator, a super-hydrophobic metal substrate, and a high-voltage electrode array. One end of the triboelectric nanogenerator is connected to the super-hydrophobic metal substrate, and the other end of the triboelectric nanogenerator is connected to the high-voltage electrode array. The high-voltage electrode array is arranged above the super-hydrophobic metal substrate. The triboelectric nanogenerator is configured to provide an alternating voltage to the high-voltage electrode array. The high-voltage electrode array is configured to control, on the basis of the alternating voltage, droplets on the super-hydrophobic metal substrate to oscillate to generate eddy current so as to heat the droplets and accelerate evaporation of the droplets. The handheld Raman spectrometer is configured to test the enriched droplets to obtain a SERS spectrum of the analyte. The present invention provides a brand-new thought for implementing rapid SERS-digital microfluidic analysis, and can be widely applied to the fields of disease diagnosis, food safety, national security, environmental engineering, etc.

Description

A self-powered, portable, and high-throughput SERS biosensing platform Technical Field

[0001] The present invention relates to the field of digital microfluidics technology, and in particular to a self-powered, portable and high-throughput SERS biosensing platform. Background Art

[0002] In recent years, surface-enhanced Raman spectroscopy (SERS) has become a powerful whole-organism fingerprint identification tool that can quickly, label-free, and non-destructively identify different chemical and biological analytes. On the other hand, the sample to be tested can be quickly and flexibly processed in the form of microdroplets (μL or nL) on the digital microfluidic chip. In other words, digital microfluidics provides the ability to pre-process fine samples, while SERS provides a fast and sensitive detection method. By making full use of the above characteristics, the portable SERS analysis technology is combined with digital microfluidics to achieve the purpose of portability, high throughput, high sensitivity and rapid analysis with a small sample volume. Therefore, the SERS-digital microfluidic biosensor conforms to the development trend of modern analytical technology and shows excellent potential in on-site instant detection in fields such as marine monitoring, food safety, and infectious disease control (such as the new coronavirus).

[0003] In SERS-digital microfluidics systems, it is usually necessary to control the gap between plasmonic metal nanostructures to less than 10 nm to create an effective signal enhancement 'hotspot'. At the same time, it is necessary to further transport the target molecules to the 'hotspot' area to obtain a better Raman enhancement effect. At present, there are two major strategies. The first is to directly combine the plasmonic metal nanostructure with the substrate, and then deposit the target molecules into the 'hotspot' area on the substrate by droplet evaporation to obtain an enhanced Raman spectral signal. However, in order to manufacture plasmonic metal nanostructures on the substrate and effectively control the related gaps, its high processing requirements bring huge application limitations.

[0004] To this end, scientists have begun exploring new methods based on the self-assembly of plasmonic metal nanoparticles and target analytes within droplets. Throughout this process, the droplets simply concentrate by evaporation to deliver the target analyte to the 'hotspot' region of the plasmonic nanostructure, thereby significantly enhancing the Raman detection signal. Therefore, the deposition distribution of the nanoparticles after enrichment plays a crucial role in detection performance, and this deposition distribution is primarily influenced by the adhesion between the droplet and the substrate during contact. Specifically, the surface wettability of the substrate and the residence time of the droplet in the contact area are two key influencing factors. Therefore, in SERS-digital microfluidics systems, the wetting properties of the substrates can be divided into four categories: standard hydrophobic SERS substrates, superhydrophobic SERS substrates, liquid-injected surface SERS substrates, and superhydrophobic-superhydrophilic micropatterned SERS substrates. Furthermore, depending on whether the droplet remains statically on the substrate, it can be further divided into static and dynamic enrichment.

[0005] For common hydrophobic substrates, the three-phase contact line (TCL) pins during evaporation. For an oblate hemispherical droplet on such a substrate, the evaporation rate at the edge is higher than at the center. To compensate for the faster evaporation losses at the edge, an internal flow field (Deegan flow) dominates, flowing radially outward toward the boundary. Consequently, driven by the radial flow, the nanoparticles within the droplet ultimately accumulate at the TCL, forming a "coffee ring pattern" around the droplet's periphery. The close packing of plasmonic metal nanoparticles and analytes on the ring results in an enhanced Raman signal.

[0006] On a superhydrophobic substrate, the droplet assumes a nearly spherical shape. Consequently, the solid-liquid contact area between the droplet and the substrate is relatively small. Furthermore, as the droplet evaporates, its three-phase contact line can recede and slide due to its extremely low contact angle hysteresis. Consequently, the nanoparticles within the droplet can ultimately be concentrated in a smaller area. Furthermore, when the droplet assumes a spherical shape, another flow mechanism (Marangoni flow) begins to dominate: a centrally symmetrical circulating vortex exists within the droplet. This circulating vortex can promote the homogenization of the nanoparticle deposition distribution, allowing more target molecules to be uniformly delivered to the hotspot region of the plasmonic metal nanostructure. However, for static droplets that are not stimulated by external energy, the internal Marangoni flow is typically weak. Given the highly mobile nature of the droplet on the superhydrophobic substrate, the droplet, under the manipulation of external energy stimulation, further forms an internal vortex field by dynamically rolling back and forth, thereby enhancing the homogenization of the internal nanoparticles and achieving a better enrichment effect.

[0007] For smooth surfaces infused with liquid, the air in the microstructures is replaced by the lubricant, eliminating the pinning effect at the three-phase contact line and demonstrating unique liquid repulsion. During droplet evaporation, as the droplet volume and lubricant-liquid contact area decrease, the contact line maintains a stable receding slip, concentrating the analyte in the droplet within a small area after evaporation.

[0008] The superhydrophobic-superhydrophilic micropatterned substrate, obtained by further fabricating a superhydrophilic micropore array on a superhydrophobic substrate, possesses a remarkable ability to anchor droplets based on hydrophilic sites. During droplet evaporation, the droplet's three-phase contact line is pinned only to the smaller hydrophilic sites. As a result, the nanoparticles within the droplet are ultimately enriched within the region defined by the hydrophilic sites. Furthermore, the superhydrophobic regions act as physical barriers, preventing cross-contamination between adjacent sample droplets and maintaining their independence during detection. Therefore, the superhydrophobic-superhydrophilic micropattern offers the advantage of high-throughput detection.

[0009] In general, scientists have conducted extensive research to rapidly and effectively generate spectral signals with high sensitivity, uniformity, and good linearity for target molecules in Raman detection, and have achieved some success. However, existing research approaches still have many limitations, making them difficult to implement in practical applications.

[0010] For example, although droplets on ordinary hydrophobic substrates can enrich metal nanoparticles and analytes through the coffee ring effect, under the combined action of radial flow (Deegan flow) and gravity, metal nanoparticles and analytes with large density differences are difficult to deposit homogeneously and are highly random, which greatly limits the detection sensitivity of the SERS substrate and the uniformity of the Raman signal.

[0011] For superhydrophobic surfaces, it is difficult to anchor droplets on the substrate, making it difficult to achieve array enrichment of droplets, and the detection flux is severely limited. Secondly, superhydrophobic substrates are not suitable for some analytes in non-aqueous phases. In addition, although the eddy currents in static droplets have a certain homogenizing effect, they are relatively weak. For this reason, a dynamic enrichment method based on the back and forth movement of droplets is proposed. This method can further improve the homogenization problem by converting external energy into eddy currents, but it requires additional energy supply and control systems to achieve continuous movement of droplets. And as the viscosity of the evaporating droplets increases, the nanoparticles will be easily adsorbed onto the moving trajectory, resulting in the loss of detection molecules.

[0012] For smooth surfaces injected with liquid, the choice of lubricant is highly dependent on the properties of the porous substrate, droplet, and nanoparticles. This poses numerous limitations in practical analysis. Furthermore, the use of lubricants inevitably contaminates the droplets and accumulates and deposits along with the nanoparticles in the droplets, potentially creating background interference in Raman measurements.

[0013] For superhydrophobic-superhydrophilic micropatterned substrates, the contact line is pinned to the hydrophilic region. Consequently, the degree of homogeneity of the nanoparticles within the droplet is typically intermediate between that of hydrophilic and superhydrophobic substrates. During evaporation, nanoparticles are more concentrated at the three-phase contact line, resulting in relatively poor signal uniformity. Furthermore, superhydrophobic-superhydrophilic micropatterned substrates are unsuitable for some analytes in non-aqueous phases.

[0014] A common drawback of these droplet evaporation-based enrichment methods is that for static droplets, the homogenization of the nanoparticles within the droplet is low. Consequently, the detection signal uniformity and linearity are mediocre. Furthermore, while dynamic enrichment of droplets on superhydrophobic substrates can significantly improve homogenization, the back-and-forth movement of droplets can easily lead to nanoparticle loss, which in turn affects overall detection performance. Furthermore, the required power supply and control system also pose a challenge to portability. Furthermore, current research often involves droplets in a naturally evaporating environment, making the enrichment process time-consuming. For example, a 20μL droplet typically requires over two hours to enrich. This significantly undermines the original purpose of on-site, point-of-care testing. To accelerate droplet enrichment, scientists have begun considering heating-assisted methods. However, existing technologies still have their limitations. For example, for hydrophilic and superhydrophobic-superhydrophilic micropatterned substrates, the coffee ring effect is strong when heated due to three-phase contact line pinning, which in turn leads to a decrease in detection performance. For smooth substrates with liquid injected into them, heating-induced lubricant evaporation ultimately leads to contact line pinning, resulting in enrichment failure. While dynamic droplets on superhydrophobic substrates effectively mitigate the heating-induced contact line pinning problem compared to the previous three substrates, the existing back-and-forth movement method can lead to nanoparticle loss.

[0015] Summary of the Invention

[0016] In order to overcome the deficiencies of the prior art, the present invention aims to provide a self-powered, portable and high-throughput SERS biosensing platform.

[0017] To achieve the above object, the present invention provides the following solutions:

[0018] A self-powered, portable and high-throughput SERS biosensing platform comprising:

[0019] Handheld Raman spectrometer, triboelectric nanogenerator, superhydrophobic metal substrate and high-voltage electrode array;

[0020] One end of the friction nanogenerator is connected to the super-hydrophobic metal substrate, and the other end of the friction nanogenerator is connected to the high-voltage electrode array; the high-voltage electrode array is arranged above the super-hydrophobic metal substrate; the friction nanogenerator is used to provide an alternating voltage to the high-voltage electrode array; the high-voltage electrode array is used to control the oscillation of the droplets on the super-hydrophobic metal substrate according to the alternating voltage, generating eddy currents to heat the droplets and accelerate the evaporation of the droplets; the handheld Raman spectrometer is used to detect the enriched droplets to obtain the SERS spectrum of the analyte.

[0021] Preferably, the high-voltage electrode array comprises a plurality of electrodes arranged at equal intervals.

[0022] Preferably, the distance between the electrode and the super-hydrophobic metal substrate is 5 mm.

[0023] Preferably, the diameter of the electrode is 2.5 mm.

[0024] Preferably, the peak voltage of the triboelectric nanogenerator is in the range of 4KV-5KV; and the rotation speed of the triboelectric nanogenerator is greater than or equal to 300r / min.

[0025] Preferably, the distance between the electrodes is 5 mm.

[0026] Preferably, the volume of the droplet is 7ul.

[0027] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0028] The present invention provides a self-powered, portable, and high-throughput SERS biosensing platform, comprising a handheld Raman spectrometer, a triboelectric nanogenerator (TGN), a superhydrophobic metal substrate, and a high-voltage electrode array. One end of the TGN is connected to the superhydrophobic metal substrate, and the other end is connected to the high-voltage electrode array. The high-voltage electrode array is disposed above the superhydrophobic metal substrate. The TGN is configured to provide an alternating voltage to the high-voltage electrode array. The high-voltage electrode array controls the oscillation of droplets on the superhydrophobic metal substrate according to the alternating voltage, generating eddy currents to heat the droplets and accelerate their evaporation. The handheld Raman spectrometer is configured to detect the enriched droplets and obtain SERS spectra of the analytes. The present invention has six key characteristics: non-destructive enrichment, high throughput, rapid detection, high sensitivity, good linearity and uniformity of the detection signal, unlimited sample types, and self-power. This platform provides a novel approach to solving the problem of rapid detection in SERS-digital microfluidics and has broad applications in fields ranging from disease diagnosis and food safety to national security and environmental engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] FIG1 is a schematic diagram of platform connection relationships provided by an embodiment of the present invention;

[0031] FIG2 is a schematic diagram of a portable self-powered SERS biosensing platform module provided by an embodiment of the present invention;

[0032] FIG3 is a schematic diagram of the reversible generation and disappearance of induced charges according to an embodiment of the present invention;

[0033] FIG4 is a schematic diagram of different droplet dynamic behaviors under different applied voltages (V) and electrode diameters provided by an embodiment of the present invention;

[0034] FIG5 is a schematic diagram of a droplet at an open circuit voltage of 6KV provided by an embodiment of the present invention;

[0035] FIG6 is a schematic diagram showing changes in the height / width ratio of a water droplet as the applied voltage increases according to an embodiment of the present invention;

[0036] FIG7 is a schematic diagram showing the relationship between the volume of the oscillating droplet and the average maximum temperature according to an embodiment of the present invention.

[0037] Explanation of the accompanying figures: 1- triboelectric nanogenerator, 2- high-voltage electrode array, 3- superhydrophobic metal substrate, 4- handheld Raman spectrometer. DETAILED DESCRIPTION

[0038] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0039] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0040] FIG1 is a schematic diagram of the platform connection relationship provided by an embodiment of the present invention. As shown in FIG1 , the present invention provides a self-powered, portable and high-throughput SERS biosensing platform, comprising:

[0041] Handheld Raman spectrometer 4, triboelectric nanogenerator 1, superhydrophobic metal substrate 3 and high-voltage electrode array 2;

[0042] One end of the friction nanogenerator 1 is connected to the super-hydrophobic metal substrate 3, and the other end of the friction nanogenerator 1 is connected to the high-voltage electrode array 2; the high-voltage electrode array 2 is arranged above the super-hydrophobic metal substrate 3; the friction nanogenerator 1 is used to provide an alternating voltage to the high-voltage electrode array 3; the high-voltage electrode array 3 is used to control the droplets on the super-hydrophobic metal substrate 3 to oscillate according to the alternating voltage, generating eddy currents to heat the droplets and accelerate the evaporation of the droplets; the handheld Raman spectrometer 4 is used to detect the enriched droplets to obtain the SERS spectrum of the analyte.

[0043] FIG2 is a schematic diagram of a portable self-powered SERS biosensor platform module provided by an embodiment of the present invention. As shown in FIG2 , this embodiment utilizes the portable and high-voltage characteristics of the solid-solid friction nano-power generation device to introduce a portable high-voltage power supply that can collect wind energy. On this basis, the high-voltage electrodes of the array form a local potential well, thereby acting as an electrostatic tweezer, and utilizing the electrostatic capture effect to form a corresponding high-throughput droplet array on the super-hydrophobic surface. Under the action of alternating voltage, the droplets oscillate and evaporate to enrich. On the one hand, the up and down oscillation of the droplets can effectively form an internal self-stirring flow field. On the other hand, the eddy current heating effect of the pulsed electric field can accelerate the evaporation of the droplets. As the droplets evaporate, a uniform dynamic enrichment can eventually be formed, and the detection is carried out by a portable Raman spectrometer (handheld Raman spectrometer), thereby realizing self-powered high-throughput SERS biosensing.

[0044] Specifically, the triboelectric nanogenerator consists of two main parts: the rotor and the stator. A nylon film (length: 238.8 mm; width: 85 mm; thickness: 60 μm) coated with four layers of copper foil (length: 85 mm; width: 58 mm; thickness: 60 μm) is bonded to the inner wall of an acrylic box (inner diameter: 76 mm; thickness: 2 mm; height: 85 mm) to form the stator. The rotor consists of an acrylic box (outer diameter: 70 mm; thickness: 2 mm; height: 76 mm) and identical upper and lower covers (outer diameter: 70 mm; inner diameter: 8 mm; thickness: 3 mm). Two sponges (length: 82 mm; width: 58 mm; thickness: 3 mm) are bonded to the surface of the cylinder and covered with two PTFE films (length: 82 mm; thickness: 30 μm). A stainless steel shaft is fixed to the inner cylinder and connected to the outer cylinder cover via a bearing.

[0045] The reversible generation and disappearance of induced charges is shown in Figure 3. After the voltage is turned off, the induced charges in the droplet disappear (neutralized by grounding), but are regenerated after the voltage is turned on, which is reversible.

[0046] The phase diagram in Figure 4 shows the dynamic behavior of a droplet under varying applied voltages (V) and electrode diameters. In region I (circles), the droplet remains stationary. In region II (triangles), the droplet moves horizontally toward the tweezers, while in region III (squares), the droplet eventually detaches from the surface due to excessive Coulomb forces. The two dashed lines represent the minimum voltages in regions II and III, respectively. Figure 5 shows that at an open-circuit voltage of 6 kV, the entire droplet (approximately 7 μL) is lifted onto the tweezers because the electrostatic force is stronger than the combined forces of gravity, the droplet's weight, and adhesion to the substrate. At 1.26 seconds, the droplet contacts the electrode and acquires a charge of the same polarity as the electrode (conduction charge), resulting in a repulsive force between the tweezers and the droplet. From 1.28 to 1.48 seconds, the droplet elongates due to the repulsive force until its bottom contacts the substrate and then bounces off, a process that continues for several cycles. At 1.57 seconds, the droplet splits into two parts, with the upper part adhering to the tweezers. In this state, the two sub-droplets are still attracted to each other due to electrostatic induction. The distance between the electrode and the substrate is about 5 mm. Considering that the peak voltage of the triboelectric nanogenerator has a certain fluctuation around 5 kV, the electrode diameter is selected to be 2.5 mm.

[0047] In Figure 6, two optical insets show that at 5 kV, the shape of the water droplet is taller and thinner than at 0 kV, demonstrating the modulated electrostatic Coulomb force between the tweezers and the water droplet. The scale bar in the optical images is 1 mm, and the error bars are based on the standard deviation of three tests.

[0048] The electric field used in electrostatic tweezers is a DC power source, while the triboelectric nanogenerator uses a pulsed power source. When the voltage is greater than or equal to 22 kV, the response time of the droplet oscillation is almost zero milliseconds. In this experiment, the spacing between the two electrodes is 27 mm, which means that the peak electric field strength needs to be greater than or equal to 0.8 kV / mm for optimal results. In summary, the peak voltage of the triboelectric nanogenerator should be between 4 kV and 5 kV for optimal droplet oscillation. This means that the triboelectric nanogenerator rotation speed should be greater than or equal to 300 r / min to achieve optimal results. At the same time, the distance between the electrode and the substrate is approximately 5 mm. Considering that the electrode diameter should be as large as possible from the droplet diameter, the electrode diameter was selected to be 2.5 mm. Since the electrodes have the same polarity and the mutual repulsive coupling is very small, there are no strict requirements for the numerical setting, and the inter-electrode spacing is also set to 5 mm here. The droplet volume is set to 7 μl.

[0049] The back-and-forth movement of droplets on the superhydrophobic surface significantly reduces their residence time, significantly reducing the area of ​​gold / analyte nanoparticle concentration within the droplet after complete evaporation, thereby increasing the degree of concentration. Simultaneously, the homogeneous eddy currents within the droplet ensure uniform distribution of the gold / analyte nanoparticles. This uniform distribution of gold nanoparticles creates a uniform hotspot, while the uniform distribution of the analyte within the hotspot produces a highly enhanced and uniform Raman signal. The droplet oscillation response time under the electrodes can approach 0 ms, which translates to a near-zero retention time. Simultaneously, symmetrical eddy currents form within the oscillating droplet. Droplets only need to oscillate up and down, eliminating the need for back-and-forth movement, significantly minimizing the amount of droplet material remaining on the substrate. Each electrode forms a separate potential well, allowing arrays to be easily connected to form high-throughput droplet arrays. The triboelectric nanogenerator is compact and can harvest natural wind or ocean current energy for power generation. Therefore, the present invention enables self-powered, non-destructive, portable, and high-throughput on-site detection of biomolecules.

[0050] Furthermore, droplet oscillation can increase the droplet generation rate and reduce the enrichment time: at a pulse voltage of 250 volts and a 25 millisecond delay time, the evaporation flux of a 3-microliter droplet is 1.47 times greater than that of a 10-microliter droplet (the smaller the droplet, the faster the evaporation rate). When the delay time is reduced from 200 milliseconds to 25 milliseconds, the evaporation flux of a 3-microliter droplet at 250 volts increases by 1.1 times (indicating that the reduction in delay time has a limited effect on droplet evaporation). When the pulse input delay time is 25 milliseconds and the peak voltage is 250 volts, the evaporation rate of a 3-ml droplet is observed to increase by approximately 18% compared to a static droplet. Due to the shorter path from the bottom droplet surface to the liquid-air interface, the oscillation-induced internal circulation enhances evaporation more significantly for smaller droplets, allowing smaller droplets to evaporate at a faster rate. In addition, due to the higher oscillation frequency, the lower delay time results in a shorter evaporation time. This leads to an additional enhancement of internal flow, improving the transport and evaporation rate within the droplet.

[0051] As shown in Figure 7, in order to study the effect of using an AC electric field on the evaporation rate of the droplets, additional experiments were conducted in this embodiment, compared with DC electrowetting (pulse). In a 5 ml droplet experiment, applying an AC electric field (250 volts) increased the evaporation rate by 6.04-6.6% in the frequency range of 2-20 Hz. The percentage increase decreased with increasing frequency, i.e., 3.45% at 200 Hz and 0.0092% at 1 kHz. However, for a DC pulse input (250 volts, 25 milliseconds), the evaporation rate of the same droplet increased by 11.15% (equivalent to an AC input of 20 Hz). This shows that a pulsed power supply can further promote the evaporation of the droplets.

[0052] Optionally, the triboelectric nanogenerator has rotating blades. Under the influence of natural wind or ocean currents, the rotating blades drive the friction between different materials in the generator, thereby generating an alternating high voltage. Compared with traditional high-voltage power supplies, it can directly convert natural energy into high-voltage electricity. It has a simple structure, a small size, and strong mobility, making it suitable for mobile operations. During the oscillating evaporation and enrichment process of droplets, the droplets jump up and down at a fixed position on the super-hydrophobic metal surface, thus avoiding the residue problem caused by reciprocating movement on the surface in traditional solutions. Therefore, it can be used for non-destructive enrichment and improve detection accuracy. Under the alternating high-voltage electric field, the droplets are further heated, which can greatly shorten the time it takes for the droplets to completely evaporate and improve the enrichment efficiency.

[0053] The beneficial effects of the present invention are as follows:

[0054] 1) The high-voltage power supply based on the friction nanogenerator has the advantages of being green, self-powered, portable, portable and low-cost.

[0055] 2) High-voltage array electrodes can be used for high-throughput manipulation of analyte-containing microdroplets.

[0056] 3) Oscillating evaporation enrichment of droplets avoids the problem of analyte loss caused by traditional mobile evaporation enrichment, thereby achieving the goal of lossless and uniform enrichment.

[0057] 4) The alternating high voltage of the friction nanogenerator can not only drive the droplets to oscillate, but also heat the droplets, thereby shortening the time for droplet evaporation and enrichment.

[0058] 5) The combination of the triboelectric nanogenerator and the handheld Raman spectroscopy instrument can make the entire biosensing platform compact and highly mobile, which is conducive to miniaturization and mobile operation.

[0059] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0060] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A self-powered, portable and high-throughput SERS biosensing platform, characterized in that: include: Handheld Raman spectrometer, triboelectric nanogenerator, superhydrophobic metal substrate and high-voltage electrode array; One end of the friction nanogenerator is connected to the super-hydrophobic metal substrate, and the other end of the friction nanogenerator is connected to the high-voltage electrode array; the high-voltage electrode array is arranged above the super-hydrophobic metal substrate; the friction nanogenerator is used to provide an alternating voltage to the high-voltage electrode array; The high-voltage electrode array is used to control the droplets on the super-hydrophobic metal substrate to oscillate according to the alternating voltage to generate eddy currents to heat the droplets and accelerate the evaporation of the droplets; the handheld Raman spectrometer is used to detect the enriched droplets to obtain the SERS spectrum of the analyte.

2. The self-powered, portable and high-throughput SERS biosensing platform according to claim 1, characterized in that: The high voltage electrode array includes a plurality of electrodes arranged at equal intervals.

3. The self-powered, portable and high-throughput SERS biosensing platform according to claim 2, characterized in that: The distance between the electrode and the super-hydrophobic metal substrate is 5 mm.

4. The self-powered, portable and high-throughput SERS biosensing platform according to claim 2, characterized in that: The diameter of the electrode is 2.5 mm.

5. The self-powered, portable and high-throughput SERS biosensing platform according to claim 1, characterized in that: The peak voltage of the friction nanogenerator is in the range of 4KV-5KV; the rotation speed of the friction nanogenerator is greater than or equal to 300r / min.

6. The self-powered, portable and high-throughput SERS biosensing platform according to claim 2, characterized in that: The spacing between the electrodes was 5 mm.

7. The self-powered, portable and high-throughput SERS biosensing platform according to claim 1, characterized in that: The volume of the droplet was 7 ul.

Images