A method of photo-induced dielectrophoretic driving programmable rapid assembly of a SERS substrate

Abstract

The application discloses a method for programmable fast assembly of SERS substrates driven by photo-induced dielectrophoresis, and relates to the technical fields of micro-nano manufacturing and surface enhanced Raman spectrum detection, and the method comprises the following steps: constructing a photo-induced electrophoresis chip; obtaining micro-nano particles and target objects to be detected; mixing the micro-nano particles and the target objects to be detected to obtain a suspension, and injecting the suspension into a liquid cavity of the photo-induced electrophoresis chip to obtain an assembled photo-induced electrophoresis chip; based on the assembled photo-induced electrophoresis chip, driving the micro-nano particles in the suspension to capture the target objects to be detected according to photo-induced convection and dielectrophoresis force through a programmable spatial light modulation device, obtaining a chimeric substrate, and performing in-situ surface enhanced Raman spectrum detection and quantitative analysis. The application solves the problems of low efficiency, poor structure controllability, insufficient uniformity and liquid phase incompatibility of traditional micro-nano assembly technology, and realizes efficient aggregation, reconfigurable assembly and in-situ SERS detection of the micro-nano particles and the target objects to be detected in a liquid environment.

Description

Technical Field

[0001] This invention relates to the fields of micro / nano fabrication and surface-enhanced Raman spectroscopy, and particularly to a method for photo-induced dielectrophoresis-driven programmable rapid assembly of SERS substrates. Background Technology

[0002] The ordered assembly of micro / nano particles is a crucial pathway to realizing high-performance optoelectronic devices, photonic crystals, and chemical sensing. Current surface-enhanced Raman scattering (SERS) substrate assembly techniques include self-assembly, chemical deposition, electric field actuation, and optical tweezers manipulation. Although these methods have been extensively studied under laboratory conditions, they still suffer from the following limitations:

[0003] Slow assembly speed and uncontrollable structure: Self-assembly and evaporation-induced methods rely on natural processes, usually requiring several minutes to several hours to form a structure, and the morphology is random and has poor uniformity.

[0004] Lack of programmable control capability: Patterns are fixed by template assistance or fixed electrodes, making it impossible to flexibly adjust the structural position and shape, and making it difficult to achieve dynamic manufacturing in multiple scenarios.

[0005] Poor uniformity and signal consistency: Random particle aggregation leads to uneven distribution of local hotspots, resulting in low repeatability of SERS signals.

[0006] Insufficient adaptability to liquid environments: Most SERS substrates rely on solid structures and cannot achieve in-situ detection in liquids.

[0007] Optically induced electrophoresis (OET) offers a novel approach to the dynamic manipulation of micro and nanoparticles due to its low power consumption, programmable control, and large-area parallel manipulation capabilities. However, current OET research primarily focuses on the capture or movement of micron-sized particles, lacking rapid, programmable assembly methods for nanoscale particles. Furthermore, the integration of OET with SERS detection is insufficient, lacking efficient, integrated assembly and detection solutions in a liquid-phase environment.

[0008] Therefore, there is an urgent need for a method to achieve rapid, programmable, and structurally uniform in-situ assembly and detection of micro- and nano-particles in liquid systems, so as to simultaneously ensure manufacturing controllability and detection sensitivity. Summary of the Invention

[0009] The purpose of this invention is to provide a method for photo-induced dielectrophoresis-driven programmable rapid assembly of SERS substrates, which solves the problems of low efficiency, poor structural controllability, insufficient uniformity and liquid phase incompatibility of traditional micro-nano assembly technology, and realizes in-situ capture and efficient aggregation of micro-nano particles and target objects to be detected in a liquid environment, reconfigurable assembly and in-situ SERS detection.

[0010] To achieve the above objectives, the present invention provides a method for photo-induced dielectrophoresis-driven programmable rapid assembly of SERS substrates, comprising the following steps:

[0011] S1. Construct a photoinduced electrophoresis chip; the photoinduced electrophoresis chip includes: a glass assembly, a transparent conductive layer, a photoconductive layer, a liquid cavity, and an AC power supply;

[0012] S2. Acquire micro / nano particles and the target analyte to be detected;

[0013] S3. Mix the micro-nano particles with the target analyte to obtain a suspension, and inject the suspension into the liquid cavity of the photoinduced electrophoresis chip to obtain the photoinduced electrophoresis chip to be assembled.

[0014] S4. Based on the photo-induced electrophoresis chip to be assembled, a programmable spatial light modulation device is used to drive micro-nano particles in the suspension to capture the target to be detected according to photo-induced convection and dielectric force, thereby obtaining a spliced ​​substrate.

[0015] S5. Using the chimeric substrate as the sensing substrate, in-situ surface-enhanced Raman spectroscopy is performed to detect and quantitatively analyze the captured target analytes.

[0016] Preferably, the specific content of S4 includes:

[0017] By using a programmable spatial light modulation device, a preset light pattern is projected onto the photoconductive layer surface of the photoinduced electrophoresis chip to be assembled, thereby obtaining the light editing area;

[0018] A non-uniform electric field is generated in the optical editing area by the light pattern and the AC power supply of the light-induced electrophoresis chip to be assembled;

[0019] Based on a non-uniform electric field, the aggregation of micro- and nano-particles in the suspension is synergistically driven by photoinduced convection and dielectric force, and the target object to be detected is captured and fixed in the photo-editing region to obtain a chimeric substrate.

[0020] Preferably, based on a non-uniform electric field, and according to photoinduced convection and dielectrophoresis, the micro-nano particles in the suspension are synergistically driven to aggregate and capture the target object to be detected, fixing it in the photo-editing region, resulting in the following specific contents of the chimeric substrate:

[0021] Based on a non-uniform electric field, micro and nano particles in a suspension are driven by light-induced convection to aggregate and form micro and nano particle clusters.

[0022] Micro- and nano-particle clusters capture the target object to be detected, thus obtaining the cluster structure;

[0023] Through dielectric electrophoresis, the cluster structure is adsorbed and fixed to the optical editing region to obtain the assembled structure, i.e., the chimeric substrate.

[0024] Preferably, the programmable spatial light modulation device includes: a digital micromirror device and a spatial light modulator.

[0025] Preferably, the photoinduced convection is formed by the liquid temperature gradient generated by the Joule heating effect caused by the change in conductivity of the photo-editing region, which is used to transport micro / nano particles and the target object to be detected to the photo-editing region; the dielectrophoretic force acts on the cluster structure, causing the cluster structure to migrate along the gradient direction of the non-uniform electric field and be fixed to the photoconductive layer surface of the photoinduced electrophoresis chip to be assembled.

[0026] Preferably, the transparent conductive layer is an indium tin oxide layer; the photoconductive layer is a hydrogenated amorphous silicon layer.

[0027] Preferably, the electric field parameters of the AC power supply are: voltage 20V-30V, frequency 10Hz-100Hz.

[0028] Preferably, the materials of the micro / nano particles include gold, silver, oxides, and composite structural materials; the composite structural materials include at least two of the materials selected from gold, silver, and oxides; and the target analytes to be detected include micro / nano particle materials and organic molecules.

[0029] The present invention also provides a system for photo-perelectrophoresis-driven programmable rapid assembly of SERS substrates, for implementing the above-described method for photo-perelectrophoresis-driven programmable rapid assembly of SERS substrates, comprising:

[0030] A chip construction module is used to construct a photoinduced electrophoresis chip; the photoinduced electrophoresis chip includes: a glass assembly, a transparent conductive layer, a photoconductive layer, a liquid cavity, and an AC power supply;

[0031] The acquisition module is used to acquire micro / nano particles and the target object to be detected;

[0032] The suspension preparation module is used to mix micro-nano particles with the target analyte to obtain a suspension, and inject the suspension into the liquid cavity of the photoinduced electrophoresis chip to obtain the photoinduced electrophoresis chip to be assembled.

[0033] The programming assembly module is used to capture the target object to be detected by micro-nano particles in the suspension based on the photoinduced electrophoresis chip to be assembled, through a programmable spatial light modulation device, according to the photoinduced convection and dielectric force, thereby obtaining the inlay substrate.

[0034] The detection and analysis module is used to perform in-situ surface-enhanced Raman spectroscopy detection and quantitative analysis on the captured target material by using the chimeric substrate as the sensing substrate.

[0035] Preferably, the system for photo-induced dielectrophoresis-driven programmable rapid assembly of SERS substrates is an integrated chip-level system used to capture the target analyte to obtain a fused substrate using micro / nano particles, and to perform in-situ surface-enhanced Raman spectroscopy detection and quantitative analysis of the target analyte.

[0036] In summary, the method for rapid assembly of a SERS substrate driven by photo-induced dielectrophoresis provided by this invention offers the following advantages compared to traditional technologies: By driving micro / nano particles and the target analyte in a suspension through photoinduced convection and dielectrophoretic force, the micro / nano particles rapidly capture the target analyte, completing the assembly of millimeter-scale complex patterns within 10 seconds. This results in rapid assembly, uniform hotspot distribution in the particle array of the intercalated substrate, and a relative standard deviation (RSD) of 8.2% for the SERS signal, significantly superior to traditional self-assembled substrates, demonstrating high structural uniformity. Furthermore, the light pattern projected by the programmable spatial light modulation device can be arbitrarily programmed, forming regular geometric structures or text arrays, exhibiting strong programmability. The assembled intercalated substrate can be directly manipulated and detected in the liquid phase without the need for drying or transfer processes. When polystyrene (PS) microplastics are used as the detection object, the SERS linear fitting correlation coefficient R0 is high. 2 The limit of detection (LOD) is 0.96, and the limit of detection (LOD) is 5.6 μg / mL. It has excellent detection performance, strong versatility, and is applicable to different material systems. It also has good potential for expansion and integration.

[0037] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of a method for photo-induced dielectrophoresis-driven programmable rapid assembly of SERS substrates according to the present invention;

[0039] Figure 2 This is a schematic diagram of the structure of the photoinduced electrophoresis chip in this invention;

[0040] Figure 3 This is a schematic diagram of the assembly principle of light-patterned micro / nano particles and the target object to be detected in this invention; wherein, (a) is a vector diagram of the light-induced convection fluid field; and (b) is a dielectric force distribution diagram.

[0041] Figure 4The diagram shows the composite substrates of the present invention; (a) is an enrichment process diagram of the rectangular composite substrate at 2s; (b) is an enrichment process diagram of the rectangular composite substrate at 6s; (c) is an enrichment process diagram of the rectangular composite substrate at 10s; (d) is an enrichment process diagram of the rectangular composite substrate at 12s; (e) is a schematic diagram of the rectangular composite substrate; (f) is a schematic diagram of the triangular composite substrate; (g) is a schematic diagram of the pentagonal composite substrate; (h) is a schematic diagram of the circular composite substrate; (i) is a scanning electron microscope image of a conventional SERS substrate at 12K magnification; (j) is a scanning electron microscope image of a conventional SERS substrate at 150K magnification; (k) is a scanning electron microscope image of a conventional SERS substrate at 150K magnification; and (l) is a scanning electron microscope image of the composite substrate of micro / nano particles and PS microplastics.

[0042] Figure 5 This invention presents the SERS signal and uniformity statistics of the intercalated substrate when PS microplastics are used as the detection object; wherein, (a) is the graph showing the change of SERS detection spectral intensity of the intercalated substrate of micro / nano particles and PS microplastics with concentration; (b) is the graph showing the 1003 cm⁻¹ SERS spectrum of PS microplastics. -1 Peak intensity variation with concentration and correction curve; (c) SERS spectrum of PS microplastics at 1003 cm⁻¹ -1 Statistical chart of peak intensity uniformity;

[0043] Figure 6 This is a system block diagram of a photo-induced dielectrophoresis-driven programmable rapid assembly SERS substrate according to the present invention.

[0044] Figure Labels

[0045] 1. Glass assembly; 2. Transparent conductive layer; 3. Photoconductive layer; 4. Spacer layer; 5. AC power supply; 6. Liquid cavity; 7. Light editing area; 8. Light source. Detailed Implementation

[0046] The technical method of the present invention will be further described below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application.

[0047] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0048] Techniques, systems, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, systems, and equipment should be considered part of the instruction manual.

[0049] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0050] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0051] This invention provides a method for photo-induced dielectrophoresis-driven programmable rapid assembly of SERS substrates, such as... Figure 1 As shown, it specifically includes:

[0052] Step S1: Construct a photoinduced electrophoresis chip. The photoinduced electrophoresis chip includes: a glass component 1, a transparent conductive layer 2, a photoconductive layer 3, an AC power supply 5, and a liquid cavity 6. The transparent conductive layer 2 is an indium tin oxide layer with a thickness of 100 nm; the photoconductive layer 3 is a hydrogenated amorphous silicon layer with a thickness of 50 nm. The electric field parameters of the AC power supply 5 are: voltage 20V-30V, frequency 10Hz-100Hz.

[0053] like Figure 2 As shown, the glass assembly 1 includes a glass substrate and a glass cover plate, which are disposed opposite to each other. Two transparent conductive layers 2 are disposed on the glass substrate and the glass cover plate, respectively. A photoconductive layer 3 is disposed on the transparent conductive layer 2 on the glass substrate. A spacer layer 4 is disposed between the photoconductive layer 3 and the transparent conductive layer 2 on the glass cover plate, together forming a liquid cavity 6 for containing liquid samples. An AC power supply 5 is used to apply a uniform alternating electric field to the liquid cavity 6, and the AC power supply 5 is electrically connected to the two transparent conductive layers 2. The photoinduced electrophoresis chip is also equipped with a light source 8, which illuminates and forms a light editing area 7.

[0054] Step S2: Obtain micro / nano particles and the target analyte to be detected. The micro / nano particles are made of materials including gold, silver, oxides, and composite materials. The composite materials include at least two of the following: gold, silver, and oxides. The target analyte to be detected includes micro / nano particle materials and organic molecules. Micro / nano particle materials include micro / nanoplastics, such as polystyrene (PS) microplastics and polyethylene terephthalate (PET) microplastics. Organic molecules include organic pollutant molecules, drug molecules, proteins, and DNA.

[0055] Step S3: Mix the micro / nano particles with the target analyte to obtain a suspension, and inject the suspension into the liquid cavity 6 of the photoinduced electrophoresis chip to obtain the photoinduced electrophoresis chip to be assembled. The suspension is uniformly distributed in the liquid cavity 6.

[0056] Step S4: Based on the photoinduced electrophoresis chip to be assembled, the micro-nano particles in the suspension are driven by a programmable spatial light modulation device to capture the target object to be detected according to the photoinduced convection and dielectric force, thus obtaining the inlay substrate.

[0057] Furthermore, step S4 can be replaced by the following steps S401 to S403, as follows:

[0058] Step S401: A preset light pattern is projected onto the surface of the photoconductive layer 3 of the photoinduced electrophoresis chip to be assembled using a programmable spatial light modulation device to obtain a light editing area. The programmable spatial light modulation device includes a digital micromirror device and a spatial light modulator.

[0059] Step S402: A non-uniform electric field is generated in the optical editing area by the light pattern and the AC power supply of the photo-induced electrophoresis chip to be assembled.

[0060] Step S403: Based on a non-uniform electric field, and according to photoinduced convection and dielectrophoresis, the micro-nano particles in the suspension are synergistically driven to aggregate and capture the target object to be detected, fixing it in the photoediting region to obtain the inlay substrate. Specifically, step S403 includes:

[0061] Based on a non-uniform electric field, micro- and nano-particles in a suspension are driven by light-induced convection to aggregate and form micro- and nano-particle clusters.

[0062] Micro- and nano-particle clusters capture the target object to be detected, thus obtaining the cluster structure.

[0063] Through dielectric electrophoresis, the cluster structure is adsorbed and fixed to the optical editing region to obtain the assembled structure, i.e., the chimeric substrate.

[0064] The photoinduced convection is formed by the liquid temperature gradient generated by the Joule heating effect caused by the change in conductivity of the photo-editing region, which is used to transport micro-nano particles and the target object to be detected to the photo-editing region; the dielectrophoretic force acts on the cluster structure, causing the cluster structure to migrate along the gradient direction of the non-uniform electric field and be fixed on the surface of the photoconductive layer 3 of the photoinduced electrophoresis chip to be assembled.

[0065] In the photoconductive layer 3 within the light-editing region, the carrier concentration increases significantly under illumination, and the conductivity rises by approximately 2-3 orders of magnitude, leading to a change in the local electric field distribution and the formation of a distinct electric field gradient. For example... Figure 3 As shown, the electric field gradient generates two main mechanisms at the boundary of the optical editing region:

[0066] Driven by fluid convection (photoinduced convection): Changes in conductivity within the photo-editing region induce a Joule heating effect, resulting in a weak temperature gradient in the suspension. This creates a ring-shaped micro-convection field at the light spot boundary, continuously transporting suspended particles to the photo-editing region boundary. This enables rapid enrichment and supply of micro / nano particles and target analytes, such as... Figure 3 As shown in (a), the streamlines represent the vector direction of the annular micro-pair flow field, and the color indicates the cross-sectional velocity in the near-surface X-direction, in μm / s. The color bars indicate their numerical range.

[0067] Dielectrophoretic fixation effect: In a non-uniform electric field, micro / nanoparticles are subjected to a dielectrophoretic force directed towards the region of high electric field strength (the magnitude of the dielectrophoretic force is proportional to the gradient of the square of the electric field strength). The micro / nanoparticles and the target object to be detected migrate towards the boundary of the optical editing region along the electric field gradient direction of the non-uniform electric field, capture the target object to be detected, and are finally fixed to the photoconductive layer 3, forming a dense and uniform assembly array.

[0068] Under the combined effect of fluid convection, micro- and nano-particles and the target object to be detected are transported over a large area rapidly, while dielectrophoresis ensures that the cluster structure is precisely positioned and stably stacked in the target region, i.e., the region of the light pattern, thereby completing high-density, reconfigurable patterned assembly within seconds, such as... Figure 3 As shown in (b), the arrows represent the dielectrophoretic force in the XY coordinate direction, the colors represent the magnitude and distribution of the dielectrophoretic force in the Z coordinate direction, and the color bars represent its numerical range.

[0069] In this invention, when a light pattern is projected onto the surface of the photoconductive layer 3 of the photo-induced electrophoresis chip to be assembled, a non-uniform electric field is generated in the light editing region by the AC power supply of the chip. In this non-uniform electric field, photoinduced convection drives the micro / nano particles and the target object in the suspension to be transported to the vicinity of the light spot region. During this transport, the micro / nano particles aggregate to form clusters and capture the target object, resulting in a cluster structure. Finally, under the action of dielectrophoretic force, the cluster structure is adsorbed and fixed in the light editing region, resulting in an assembled structure, i.e., a spliced ​​substrate. Therefore, the spliced ​​substrate is a spliced ​​structure of micro / nano particles and the target object.

[0070] This invention allows for the flexible and customized manufacturing of different geometric structures (such as rectangles, circles, triangles, and pentagons) by adjusting the light pattern, the illumination intensity of the light source 8, and the electric field parameters of the AC power supply 5. Furthermore, the light pattern can be dynamically switched, enabling continuous assembly of multiple patterns.

[0071] Step S5: Using the SERS substrate as the sensing substrate, perform in-situ surface-enhanced Raman spectroscopy detection and quantitative analysis on the captured target analyte. Optionally, the liquid can be removed to fix the SERS substrate onto the substrate, or SERS detection can be performed directly in the liquid.

[0072] In an exemplary embodiment of the present invention, based on the photoinduced electrophoresis chip of the present invention, a liquid cavity 6 is formed by using 150μm thick double-sided adhesive tape, a photoconductive layer 3, and a transparent conductive layer 2 on a glass cover plate, and an AC power supply 5 with a voltage of 20V and a frequency of 20Hz. A light pattern is projected through a digital micromirror device, causing micro-nano particles suspended in the liquid and the target object to be detected to be driven by dielectric force and rapidly aggregate in the light-editing area to form a regular array. Using PS microplastics as the target object, by projecting light patterns of different shapes, including rectangles, circles, triangles, and pentagons, rapid and controllable assembly of micro-nano particles and PS microplastic intercalation structures can be achieved in a liquid environment to obtain an intercalation substrate, such as... Figure 4 As shown, the increased conductivity of the optically edited region leads to a Joule heating effect, which in turn forms a ring-shaped micro-convection field at the edge of the light spot, continuously transporting the micro-nanoparticles and PS microplastics to the edge of the target region. Simultaneously, the dielectric force induced by the local non-uniform electric field fixes the cluster structure of micro-nanoparticles and PS microplastics to the surface of photoconductive layer 3, realizing the construction of a high-fidelity two-dimensional array (chimera substrate) guided by light patterns.

[0073] Figure 4 (a), (b), (c), and (d) in the figure are enrichment process diagrams of rectangular interlocking substrates at 2s, 6s, 10s, and 12s, respectively, showing that a stable array can be formed within a few seconds (12s). Figure 4 (e), (f), (g), and (h) are the mating substrate diagrams of rectangles, triangles, pentagons, and circles, respectively. It can be seen that the pattern boundaries are clear and the micro-nano particles are evenly distributed, which can flexibly realize the assembly of mating substrates with different geometric structures. Figure 4 In the image, (i), (j), and (k) are scanning electron microscope (SEM) images of a conventional SERS substrate. Figure 4 Image (l) in the image is a scanning electron microscope image of the intercalated substrate of micro / nanoparticles and PS microplastics, and... Figure 4 Compared to (i), (j), and (k) in the original text, Figure 4 (l) clearly shows that the micro-nanoparticles are closely packed and form an interlocking contact interface with the captured PS microplastics, such as Figure 4 The dashed line marked in (l) reveals the detailed structure of the interstices between micro-nano particles and the surface of PS microplastics, providing a stable "hot spot" distribution for localized enhancement of electromagnetic fields.

[0074] After in-situ assembly, the assembled structure was used as a substrate for the detection of PS microplastics in liquid. Figure 5 As shown. Figure 5In (a) and (b), as the concentration of PS microplastics increases (range 5.6 μg / mL-50 μg / mL), the intensity of the characteristic Raman peak signal gradually increases, exhibiting a good linear response. The linear equation is B = 26.6A + 495.2 (where A is the concentration and B is the intensity). The SERS linear fitting correlation coefficient R0 is [missing value]. 2 It is 0.96. For example... Figure 5 (c) Repeat detection results indicate that the SERS spectrum of PS microplastics located at 1003 cm⁻¹ -1 The peak intensity RSD of 8.2% indicates that the assembled chimeric substrate has high uniformity and repeatability. Furthermore, the LOD of 5.6 μg / mL fully verifies the high sensitivity of the photo-dielectrophoresis-driven programmable rapid assembly method for SERS substrates provided by this invention in the detection of PS microplastics. It is evident that the photo-dielectrophoresis-driven programmable rapid assembly method for SERS substrates provided by this invention can achieve sensitive and stable microplastic detection in aqueous phases. Moreover, this invention is applicable to the rapid assembly of particles of different materials (such as gold, silver, and oxides), and can also be extended to fields such as biomolecule capture and optical coding arrays.

[0075] This invention combines photoinduced electrophoresis technology to achieve rapid programmable assembly of micro / nano particles and target objects in a liquid environment and its application in surface-enhanced Raman scattering detection. The above processes are all completed on the same chip platform for assembly, curing and detection, demonstrating the dual advantages of simplified process and improved detection sensitivity.

[0076] In summary, this invention presents an integrated solution for programmable assembly of micro / nanoparticles and SERS detection based on photoinduced electrophoresis. The core advantages of this method for rapidly assembling SERS substrates driven by photoinduced mesoelectrophoresis are its fast assembly speed, controllable shape, and ability to fabricate arrays under various light patterns. It also features a dense and uniform structure with excellent electromagnetic field enhancement consistency, high detection sensitivity, and good repeatability. This provides a novel and efficient approach for detecting complex liquid samples (such as microplastics in water), enabling precise manipulation and structured assembly of micro / nanoparticles and target analytes in liquid environments. It is suitable for microstructure manufacturing and pollutant detection, and has significant application value, especially in the sensitive identification and quantitative detection of microplastics in water.

[0077] This invention provides a system for photo-perelectrophoresis-driven programmable rapid assembly of SERS substrates, used to implement the aforementioned method for photo-perelectrophoresis-driven programmable rapid assembly of SERS substrates, such as... Figure 6 As shown, it includes:

[0078] The chip construction module is used to build a photoinduced electrophoresis chip. The photoinduced electrophoresis chip includes: a glass assembly, a transparent conductive layer, a photoconductive layer, a liquid cavity, and an AC power supply.

[0079] The acquisition module is used to acquire micro / nano particles and the target object to be detected.

[0080] The suspension preparation module is used to mix micro-nano particles with the target analyte to obtain a suspension, and then inject the suspension into the liquid cavity of the photoinduced electrophoresis chip to obtain the photoinduced electrophoresis chip to be assembled.

[0081] The programming assembly module is used to capture the target object to be detected by micro-nano particles in the suspension based on the photoinduced electrophoresis chip to be assembled, through a programmable spatial light modulation device, according to the photoinduced convection and dielectric force, to obtain the chimeric substrate.

[0082] The detection and analysis module is used to perform in-situ surface-enhanced Raman spectroscopy detection and quantitative analysis on the captured target material by using the chimeric substrate as the sensing substrate.

[0083] The system for photo-induced dielectrophoresis-driven programmable rapid assembly of SERS substrates provided by this invention is an integrated chip-level system used for capturing target objects to be detected by micro-nano particles to obtain a fused substrate, and for in-situ surface-enhanced Raman spectroscopy detection and quantitative analysis of the target objects to be detected.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method of optically induced dielectrophoretic driving programmable rapid assembly of a SERS substrate, characterized in that, Includes the following steps: S1. Construct a photoinduced electrophoresis chip; The photoinduced electrophoresis chip includes: a glass assembly, a transparent conductive layer, a photoconductive layer, a liquid cavity, and an AC power supply; S2. Acquire micro / nano particles and the target analyte to be detected; S3. Mix the micro-nano particles with the target to be detected to obtain a suspension, and inject the suspension into the liquid cavity of the photoinduced electrophoresis chip to obtain the photoinduced electrophoresis chip to be assembled. S4. Based on the photo-induced electrophoresis chip to be assembled, a programmable spatial light modulation device is used to drive micro-nano particles in the suspension to capture the target to be detected according to photo-induced convection and dielectric force, thereby obtaining a spliced ​​substrate. S5. Using the chimeric substrate as the sensing substrate, in-situ surface-enhanced Raman spectroscopy is performed to detect and quantitatively analyze the captured target analytes. The specific content of S4 includes: By using a programmable spatial light modulation device, a preset light pattern is projected onto the photoconductive layer surface of the photoinduced electrophoresis chip to be assembled, thereby obtaining the light editing area; A non-uniform electric field is generated in the optical editing region by the alternating electric field of the optical pattern and the photoinduced electrophoresis chip to be assembled; Based on a non-uniform electric field, the aggregation of micro and nano particles in the suspension is synergistically driven by photoinduced convection and dielectrophoresis, and the target object to be detected is captured and fixed in the photoediting region to obtain a chimeric substrate; Based on a non-uniform electric field, and through photoinduced convection and dielectrophoresis, micro- and nano-particles in the suspension are synergistically driven to aggregate and capture the target analyte, fixing it within the photoedited region. The specific contents of the resulting chimeric substrate include: Based on a non-uniform electric field, micro and nano particles in a suspension are driven by light-induced convection to aggregate and form micro and nano particle clusters. Micro- and nano-particle clusters capture the target object to be detected, thus obtaining the cluster structure; Through dielectric electrophoresis, the cluster structure is adsorbed and fixed in the optical editing region to obtain the assembled structure, i.e., the intercalation substrate; The programmable spatial light modulation device includes: a digital micromirror device and a spatial light modulator.

2. The method of claim 1, wherein the method is characterized by, The photoinduced convection is formed by the liquid temperature gradient generated by the Joule heating effect caused by the change in conductivity of the photo-editing region, which is used to transport micro-nano particles and the target object to be detected to the photo-editing region; the dielectric force acts on the cluster structure, causing the cluster structure to migrate along the gradient direction of the non-uniform electric field and be fixed on the photoconductive layer surface of the photoinduced electrophoresis chip to be assembled.

3. The method of claim 1, wherein the method is characterized by, The transparent conductive layer is an indium tin oxide layer; the photoconductive layer is a hydrogenated amorphous silicon layer.

4. The method of claim 1, wherein the method is characterized by, The electric field parameters of the AC power supply are: voltage 20V-30V, frequency 10Hz-100Hz.

5. The method of claim 1, wherein the method is a method of optically driven dielectrophoretic programmable rapid assembly of SERS substrates. The materials of the micro / nanoparticles include gold, silver, oxides, and composite structural materials; the composite structural materials include at least two of the materials selected from gold, silver, and oxides; the target analytes to be detected include micro / nanoparticle materials and organic molecules.

6. A system for optically induced dielectrophoretic driving programmable rapid assembly of SERS substrates, characterized in that, A method for implementing a photo-induced dielectrophoresis-driven programmable rapid assembly of a SERS substrate as described in any one of claims 1-5 includes: A chip construction module is used to construct a photoinduced electrophoresis chip; the photoinduced electrophoresis chip includes: a glass assembly, a transparent conductive layer, a photoconductive layer, a liquid cavity, and an AC power supply; The acquisition module is used to acquire micro / nano particles and the target object to be detected; The suspension preparation module is used to mix micro-nano particles with the target analyte to obtain a suspension, and inject the suspension into the liquid cavity of the photoinduced electrophoresis chip to obtain the photoinduced electrophoresis chip to be assembled. The programming assembly module is used to capture the target object to be detected by micro-nano particles in the suspension based on the photoinduced electrophoresis chip to be assembled, through a programmable spatial light modulation device, according to the photoinduced convection and dielectric force, thereby obtaining the inlay substrate. The detection and analysis module is used to perform in-situ surface-enhanced Raman spectroscopy detection and quantitative analysis of the captured target analytes by using the SERS substrate as the sensing substrate.

7. The system of claim 6, wherein the system is a photodielectrophoretically driven programmable rapid assembly SERS substrate system. The system for photo-induced dielectrophoresis-driven programmable rapid assembly of intercalation substrates is an integrated chip-level system used to capture the target object to be detected by micro-nano particles to obtain the intercalation substrate, and to perform in-situ surface-enhanced Raman spectroscopy detection and quantitative analysis of the target object to be detected.

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