Three-dimensional paper-based rotary microfluidic device

Abstract

The application relates to the field of microfluidic technology, in particular to a three-dimensional paper-based rotary microfluidic device, which comprises a first functional layer, a second functional layer and a third functional layer which are stacked from top to bottom, a rotating shaft is arranged on the upper surface of the third functional layer, the first functional layer is provided with a first shaft hole allowing rotation along the rotating shaft, and the second functional layer is provided with a second shaft hole allowing rotation along the rotating shaft; the first functional layer is provided with a sample inlet hole and an adsorption block at the bottom; the second functional layer is provided with a sample receiving groove matched with the sample inlet hole and a sample separation and enrichment hole matched with the adsorption block, the sample receiving groove is connected with the sample separation and enrichment hole through a sample flow groove, and the sample separation and enrichment hole is crossly provided with a paper-based bearing sheet for separating samples; and the third functional layer is provided with a sample analysis block matched with the sample separation and enrichment hole. The device can simultaneously perform the steps of sample feeding, impurity analysis, flow separation, separation and enrichment and detection on multiple samples.

Description

Technical Field

[0001] This invention relates to the field of microfluidics, and in particular to a three-dimensional paper-based rotating microfluidic device. Background Technology

[0002] In recent years, food safety has become a major public concern. Edible oil, as a necessity, has seen its demand steadily increase year by year, and China currently ranks first globally in edible oil consumption. Therefore, ensuring the safety and quality of edible oil is crucial. Edible oil is easily contaminated and spoiled during production and cooking. Benzo[a]pyrene (BaP), a potent carcinogen, is readily produced during this process and can accumulate in the body over a long period, leading to death and seriously impacting public health and safety. Currently, commonly used methods for detecting BaP include high-performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS), fluorescence spectroscopy, and Raman scattering (SERS). These traditional methods mostly require expensive equipment, involve complex and time-consuming detection steps, and consume large amounts of chemical reagents. Therefore, developing a novel detection method to overcome the shortcomings of the above methods is a current research hotspot and challenge.

[0003] Microfluidics paper-based devices (μPADs) were first proposed by Martinez et al. in 2007. They fabricated closed hydrophobic boundaries on paper to form microfluidic channels, which then directed samples to the detection area to react with the substrate via capillary action. Subsequently, the first 3D paper chip was fabricated for rapid detection of target analytes. Paper as a substrate material has several advantages: (1) it is widely available and inexpensive; (2) it is lightweight and thin, making it easy to store and transport; (3) it is easy to process and modify, with convenient operations such as printing, coating, modification, and cutting; (4) it is biodegradable and environmentally friendly; (5) it possesses certain mechanical strength, allowing for the construction of multi-layered channel support structures through shaping and layering; and (6) the capillary effect of paper enables liquids to flow automatically without external pumps, avoiding the bubble problem common in traditional microfluidic systems.

[0004] Therefore, research on paper-based microfluidic analytical devices (μPADs) is increasing in the field of food testing, and they have the potential to become a replacement for traditional microfluidic chips in applications such as food quality monitoring. It is crucial to provide a paper-based microfluidic device that is highly applicable, easy to process, and has low processing costs. Summary of the Invention

[0005] To address the aforementioned issues, the present invention aims to provide a three-dimensional paper-based rotating microfluidic device, which improves the production efficiency and reduces the production cost of microfluidic chips. This device utilizes a layered construction approach to mount various functional structures of the microfluidic device onto different functional layers. Each functional layer possesses functions such as sample addition, adsorption, sample reception, sample flow, sample separation and enrichment, and sample analysis. It offers high applicability, simple processing, low processing cost, and the ability to simultaneously analyze different samples.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] This invention provides a three-dimensional paper-based rotating microfluidic device, which is used in conjunction with an external Raman spectrometer. It includes a first functional layer, a second functional layer and a third functional layer stacked from top to bottom. The upper surface of the third functional layer is provided with a rotation axis. The first functional layer is provided with a first axial hole that allows rotation along the rotation axis. The second functional layer is provided with a second axial hole that allows rotation along the rotation axis.

[0008] The first functional layer is provided with a sample inlet, and an adsorption block is provided at the bottom of the first functional layer. The surface of the adsorption block is provided with adsorption paper (e.g., filter paper with both hydrophobic and oil-absorbing properties). The second functional layer is provided with a sample receiving groove adapted to the sample inlet and a sample separation and enrichment hole adapted to the adsorption block. The sample receiving groove is connected to the sample separation and enrichment hole through a sample flow groove. The sample separation and enrichment hole is provided with paper-based support sheets for separating samples. The surfaces of the sample receiving groove, sample flow groove and sample separation and enrichment hole are provided with filter paper (e.g., hydrophilic filter paper). The third functional layer is provided with a sample analysis block adapted to the sample separation and enrichment hole. The surface of the sample analysis block is provided with filter paper (e.g., hydrophilic filter paper).

[0009] The adsorption block, in conjunction with the adsorption paper, is used to adsorb impurities remaining after the sample is separated and enriched by the sample separation and enrichment pores; the sample analysis block, in conjunction with the filter paper and an external Raman spectrometer, is used to analyze the components of the sample after it has been separated and enriched by the sample separation and enrichment pores and the filter paper.

[0010] In one embodiment of the present invention, the first axial hole is disposed at the center of the first functional layer;

[0011] Several injection ports are arranged circumferentially along the first axial hole, and several adsorption blocks are arranged symmetrically along the first axial hole on the side of the injection port away from the first axial hole.

[0012] Preferably, the sample inlet is a fan-shaped sample inlet symmetrically arranged along the first central hole, and the adsorption block is a circular adsorption block symmetrically arranged along the first central hole; the sample receiving groove is a circular sample receiving hole, the sample flow groove is a rectangular sample flow groove, and the sample separation and enrichment hole is a circular sample separation and enrichment hole; the sample receiving groove and the sample analysis block are hydrophilic regions; the edge dimensions of the sample analysis block and the adsorption block are the same.

[0013] In one embodiment of the present invention, the second axial hole is disposed at the center of the second functional layer;

[0014] The size of the sample receiving slot is smaller than the size of the sample inlet;

[0015] The paper-based carrier sheet is in the form of a thin, elongated strip.

[0016] In one embodiment of the present invention, the sample flow groove is disposed on the side of the sample receiving groove away from the second axial hole; the sample separation and enrichment hole is disposed on the side of the sample flow groove away from the second axial hole;

[0017] Each set of sample receiving cells is equipped with several sample flow channels and sample separation and enrichment holes connected to the sample flow channels.

[0018] The lower surface of the second functional layer is provided with concentric circular grooves that allow relative movement with the sample analysis block.

[0019] In one embodiment of the present invention, the width of the concentric groove is the maximum outer diameter of the sample separation and enrichment pore.

[0020] In one embodiment of the present invention, the size of the sample analysis block is smaller than the size of the sample separation and enrichment pore.

[0021] In one embodiment of the present invention, the depth of the sample flow groove gradually increases along the direction of the sample separation and enrichment orifice of the sample receiving groove.

[0022] In one embodiment of the present invention, a first auxiliary moving block that allows rotation of the first functional layer is provided at the end of the first functional layer;

[0023] The end of the second functional layer is provided with a second auxiliary moving block that allows the second functional layer to be rotated.

[0024] In one embodiment of the present invention, the thickness of the adsorption block is the same as the height of the upper surface of the sample separation and enrichment pore from the upper surface of the second functional layer, so as to ensure that the lower surface of the adsorption block can be closely attached to the upper surface of the sample separation and enrichment pore.

[0025] In one embodiment of the present invention, the thickness of the sample analysis block is the same as the height of the lower surface of the sample separation and enrichment well from the lower surface of the second functional layer, so as to ensure that the upper surface of the sample analysis block can be closely attached to the lower surface of the sample separation and enrichment well.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) The three-dimensional paper-based rotating microfluidic device provided by the present invention adopts a layered superposition structure, dividing the microfluidic device into three functional layers. The first functional layer has a sample injection area (injection hole) and an impurity adsorption area (adsorption block). The second functional layer has a sample receiving area (sample receiving groove), a sample flow groove, a sample separation and enrichment hole, and a concentric circular groove that allows relative movement with the sample analysis block. The third functional layer has a sample analysis area (sample analysis block) for sample detection. The functional layers are connected by a rotatable concentric shaft.

[0028] (2) The three-dimensional paper-based rotating microfluidic device provided by the present invention can be fabricated separately for each functional layer. The height and thickness of the adsorption block and the sample analysis block can be adjusted according to the requirements to achieve different bonding effects. The tilt angle of the sample flow channel can also be adjusted according to the required sample flow rate to achieve microchannels with different flow rate specifications. The aperture size of the paper selected for the sample receiving channel and the sample separation enrichment hole can be adjusted as needed to achieve arbitrary control of the sample detection flow rate. The synergy of the above contents achieves the purpose of optimizing the detection performance and detection efficiency of the microfluidic device.

[0029] (3) The three-dimensional paper-based rotating microfluidic device provided by the present invention realizes the cooperation between various functional structural units of microfluidics in a layered construction manner, which reduces the probability of deformation during the assembly of the microfluidic device and can improve the quality level of the microfluidic device. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the overall structure of a three-dimensional paper-based rotating microfluidic device according to Embodiment 1;

[0031] Figure 2 This is a front view of the first functional layer of a three-dimensional paper-based rotating microfluidic device according to Embodiment 1;

[0032] Figure 3 This is a reverse schematic diagram of the first functional layer of a three-dimensional paper-based rotating microfluidic device according to Embodiment 1;

[0033] Figure 4 This is a front view of the second functional layer of a three-dimensional paper-based rotating microfluidic device according to Embodiment 1;

[0034] Figure 5 This is a reverse schematic diagram of the second functional layer of a three-dimensional paper-based rotating microfluidic device according to Embodiment 1;

[0035] Figure 6 This is a front view of the third functional layer of a three-dimensional paper-based rotating microfluidic device according to Embodiment 1;

[0036] Figure 7 The results of detecting B[a]P solutions of different concentrations using a three-dimensional paper-based rotating microfluidic device and a Raman spectrometer are shown in the figure.

[0037] Figure 8 The results of Raman spectroscopy analysis were obtained for B[a]P solutions of different concentrations.

[0038] Reference numerals: 1. First functional layer; 11. First auxiliary moving block; 12. Sample inlet; 13. First axial hole; 14. Adsorption block; 2. Second functional layer; 21. Second auxiliary moving block; 22. Second axial hole; 23. Sample receiving groove; 24. Sample flow groove; 25. Sample separation and enrichment hole; 26. Concentric groove; 3. Third functional layer; 31. Rotating shaft; 32. Sample analysis block. Detailed Implementation

[0039] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0040] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0041] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0042] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0043] In the following embodiments, unless otherwise specified, the structures or components used are conventional structures or components in the art, as long as they can achieve the corresponding functions; unless otherwise specified, the reagents used are commercially available reagents, and the detection methods and means used are conventional detection methods and means in the art.

[0044] Example 1

[0045] This embodiment provides a three-dimensional paper-based rotating microfluidic device, such as... Figures 1-6 As shown, a three-dimensional paper-based rotating microfluidic device is used in conjunction with an external Raman spectrometer. It includes a first functional layer 1, a second functional layer 2, and a third functional layer 3 stacked sequentially from top to bottom. A rotation axis 31 is provided on the upper surface of the third functional layer 3. The first functional layer 1 is provided with a first axial hole 13 that allows rotation along the rotation axis 31. The second functional layer 2 is provided with a second axial hole 22 that allows rotation along the rotation axis 31.

[0046] The first functional layer 1 is provided with a sample inlet 12, and an adsorption block 14 is provided at the bottom of the first functional layer 1. The surface of the adsorption block 14 is provided with adsorption paper. The second functional layer 2 is provided with a sample receiving groove 23 adapted to the sample inlet 12 and a sample separation and enrichment hole 25 adapted to the adsorption block 14. The sample receiving groove 23 is connected to the sample separation and enrichment hole 25 through a sample flow groove 24. The sample separation and enrichment hole 25 is provided with paper-based support sheets for separating samples. The surfaces of the sample receiving groove 23, the sample flow groove 24 and the sample separation and enrichment hole 25 are provided with filter paper. The third functional layer 3 is provided with a sample analysis block 32 adapted to the sample separation and enrichment hole 25. The surface of the sample analysis block 32 is provided with filter paper.

[0047] The adsorption block 14, in conjunction with the adsorption paper, is used to adsorb the impurities remaining after the sample is separated and enriched by the sample separation and enrichment well 25; the sample analysis block 32, in conjunction with the filter paper and the external Raman spectrometer, is used to analyze the components of the sample after it is separated and enriched by the sample separation and enrichment well 25 and the filter paper.

[0048] Furthermore, the first axial hole 13 is located at the center of the first functional layer 1; several sample inlets 12 are arranged around the first axial hole 13, and several adsorption blocks 14 are arranged on the side of the sample inlet 12 away from the first axial hole 13, and several are arranged symmetrically around the first axial hole 13.

[0049] Preferably, the sample inlet 12 is a fan-shaped sample inlet 12 symmetrically arranged along the first central hole 13, and the adsorption block 14 is a circular adsorption block 14 symmetrically arranged along the first central hole 13; the sample receiving groove 23 is a circular sample receiving hole, the sample flow groove 24 is a rectangular sample flow groove 24, and the sample separation and enrichment hole 25 is a circular sample separation and enrichment hole 25; the sample receiving groove 23 and the sample analysis block 32 are hydrophilic regions; the sample analysis block 32 and the adsorption block 14 have the same edge size.

[0050] Furthermore, the second axial hole 22 is located at the center of the second functional layer 2; the size of the sample receiving groove 23 is smaller than the size of the sample inlet hole 12; and the paper-based carrier sheet is in the shape of a thin strip.

[0051] Furthermore, the sample flow groove 24 is disposed on the side of the sample receiving groove 23 away from the second axial hole 22; the sample separation and enrichment hole 25 is disposed on the side of the sample flow groove 24 away from the second axial hole 22.

[0052] Each sample receiving slot 23 is provided with several sample flow slots 24 and sample separation and enrichment holes 25 connected to the several sample flow slots 24.

[0053] The lower surface of the second functional layer 2 is provided with concentric circular grooves 26 that allow relative movement with the sample analysis block 32.

[0054] Furthermore, the width of the concentric groove 26 is the maximum outer diameter of the sample separation and enrichment hole 25.

[0055] Furthermore, the size of the sample analysis block 32 is smaller than the size of the sample separation and enrichment pore 25, and the size of the adsorption block 14 is smaller than the size of the sample separation and enrichment pore 25.

[0056] Furthermore, the depth of the sample flow channel 24 gradually increases along the direction from the sample receiving channel 23 to the sample separation and enrichment hole 25.

[0057] Furthermore, the end of the first functional layer 1 is provided with a first auxiliary moving block 11 that allows the first functional layer 1 to rotate; the end of the second functional layer 2 is provided with a second auxiliary moving block 21 that allows the second functional layer 2 to rotate.

[0058] Furthermore, the thickness of the adsorption block 14 is the same as the height of the upper surface of the sample separation and enrichment hole 25 from the upper surface of the second functional layer 2, so as to ensure that the lower surface of the adsorption block 14 can be closely attached to the upper surface of the sample separation and enrichment hole 25.

[0059] Furthermore, the thickness of the sample analysis block 32 is the same as the height of the lower surface of the sample separation and enrichment hole 25 from the lower surface of the second functional layer 2, so as to ensure that the upper surface of the sample analysis block 32 can be closely attached to the lower surface of the sample separation and enrichment hole 25.

[0060] The three-dimensional paper-based rotary microfluidic device provided in this embodiment can be prepared by the following method:

[0061] (1) Preparation of the first functional layer 1: The first functional layer 1 is obtained by instrument printing. Adsorption paper with different adsorption properties is selected as needed, and after being cut, it is placed on the lower surface of the adsorption block 14.

[0062] (2) Preparation of the second functional layer 2: The second functional layer 2 (including the cross-arranged paper-based carrier sheet) is obtained by instrument printing. Different pore sizes of Whatman filter paper are selected as needed and placed on the sample receiving groove 23, sample flow groove 24 and the upper surface of the paper-based carrier sheet by cutting.

[0063] (3) Preparation of the third functional layer 3: The third functional layer 3 is obtained by instrument printing. Different pore sizes of Whatman filter paper are selected as needed and placed on the upper surface of the sample analysis block 32 by cutting.

[0064] The terms "corresponding" and "compatible" mean that when the functional layers of the three-dimensional paper-based rotating microfluidic device are stacked and aligned, the projections of the corresponding components (such as the sample inlet 12 and sample receiving groove 23, the adsorption block 14 and sample separation and enrichment hole 25, the sample separation and enrichment hole 25 and sample analysis block 32, etc.) coincide in the vertical direction.

[0065] For example, sample separation and enrichment well 25 is intended to hold a cellulose filter paper pre-loaded with a molecularly imprinted polymer containing the target molecule. This polymer-imprinted cellulose filter paper can specifically capture molecules whose molecular shape, size, and functional groups match those of the target molecule. Specifically, the polymer-imprinted cellulose filter paper uses the target molecule as a "mold," forming complementary stereostructures and functional groups within the polymer through chemical or physical means. Subsequently, the template molecule is removed using physical or chemical methods (such as elution), leaving cavities that match the shape, size, and functional groups of the template molecule. These "cavities" can specifically capture molecules that match the cavity, while other molecules are separated, thus achieving specific separation and enrichment.

[0066] For example, a cellulose filter paper modified with a signal-enhancing substrate (such as Raman signal) is planned to be placed in the sample analysis area on the front of the third functional layer 3. The signal-enhancing substrate pre-loaded on the cellulose filter paper can significantly enhance the signal intensity (Raman signal) of the target molecule. This signal can be rapidly obtained by irradiating the sample analysis area of ​​the third functional layer 3 with a laser using a portable Raman spectrometer, thereby realizing qualitative and quantitative analysis of the substance.

[0067] Example 2

[0068] This embodiment provides a method for using the three-dimensional paper-based rotating microfluidic device described in Embodiment 1, as detailed below:

[0069] The second functional layer of Whatman filter paper is prepared by the following method:

[0070] Prepolymer solutions were prepared by mixing 0.1 mM BaP (acetonitrile:methanol = 3:1 (V:V)), pyrene, and onion as template molecules with dopamine solution (1:10, V:V) (buffered in 10 mM Tris-HCl at pH 8.5) at a constant temperature and stirring for 10 min to obtain a homogeneous mixture, which was kept in the dark throughout the process. Pretreated Whatman filter paper was then immersed in the prepolymer solution until completely wetted. Ammonium persulfate (APS) was added to a final concentration of 1 mM, and the mixture was stirred and sealed at room temperature in the dark for 12 h. The filter paper was then removed, rinsed three times with deionized water, and vacuum dried again for 2 h. Finally, the eluent (V... 甲苯 V 甲醇 =8:2) Remove plates until they are no longer detected by UV-vis, to obtain Whatman / PDA-MIP with template molecules removed.

[0071] The third functional layer of Whatman filter paper is prepared by the following method:

[0072] 90 mg of silver nitrate was dissolved in 500 mL of water and boiled. Then, 10 mL of 1% sodium citrate solution was added, and boiling continued for 1 hour. Subsequently, 20 μL of a 0.1 M KCl aqueous solution was added to 1000 mL of AgNPs suspension; this KCl aqueous solution was used to activate the AgNPs surface. Finally, 10 μL of Viologens was added to a final concentration of 1 × 10⁻⁶. -4 M, then the solution was thoroughly mixed by sonication, and the previously pretreated Whatman filter paper was immersed in the solution for 1 hour. The filter paper was then removed, rinsed three times with deionized water, and vacuum dried for 2 hours to obtain Whatman / AgNPs-Viologens.

[0073] The pretreated Whatman filter paper was prepared by the following method:

[0074] First, cut the Whatman filter paper into circles of the required size (r = 0.5 cm), immerse it in anhydrous ethanol for 20 minutes of ultrasonic cleaning to remove surface impurities; then remove the filter paper, rinse it three times with deionized water and place it in a vacuum drying oven at 60°C for 2 hours; then immerse the dried filter paper in 0.1 M NaOH solution and let it stand for 5 minutes, then remove the filter paper, rinse it with deionized water until neutral (pH test paper test), and place it again in a vacuum drying oven at 60°C for 1 hour, and store it in a desiccator for later use.

[0075] When using, place the liquid sample (each with a concentration of 1×10⁻⁶) into the container. -4 g / ml, 1×10 -5 g / ml, 1×10 -6 g / ml, 1×10 -7 g / ml, 1×10 -8 g / ml, 1×10 -9 g / ml, 1×10 -10 g / ml, 1×10 -11 g / ml, 1×10 -12 g / ml, 1×10 -13 g / ml, 1×10 -14 g / ml, 1×10 -15 g / ml, 1×10 -16 A 1000 g / ml B[a]P solution is added through the injection port 12. The liquid sample enters the sample receiving tank 23 through the injection port 12, and then enters the sample separation and enrichment port 25 through the sample flow tank 24. After enrichment is completed in the sample separation and enrichment port 25, the adsorption block 14 is rotated to the corresponding sample separation and enrichment port 25 to make the adsorption block 14 and the sample separation and enrichment port 25 fit tightly to adsorb the enriched impurities. Then, the adsorption block 14 is removed by rotation. Then, the sample separation and enrichment port 25 is rotated to the upper surface of the corresponding sample analysis block 32 to make the sample analysis block 32 fit tightly to the sample separation and enrichment port 25. Finally, the sample analysis block 32 is analyzed by an external portable Raman spectrometer (e.g., sample analysis of the sample substances). Figure 7 (As shown).

[0076] Using only Raman spectroscopy, the concentrations of 1×10 were detected. -5 g / ml, 1×10 -6 g / ml, 1×10 -7 g / ml, 1×10 -8 g / ml, 1×10 -9 g / ml, 1×10 -10 g / ml, 1×10 -11 g / ml, 1×10 -12 The results of the g / ml B[a]P solution are as follows: Figure 8As shown.

[0077] pass Figure 7 and Figure 8 It can be seen that the three-dimensional paper-based rotating microfluidic device provided by the present invention can improve detection efficiency while improving detection sensitivity.

[0078] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the interpretation of the present invention, without departing from the scope of the invention, should be within the protection scope of the present invention.

Claims

1. A three-dimensional paper-based rotating microfluidic device, used in conjunction with an external Raman spectrometer, characterized in that, It includes a first functional layer (1), a second functional layer (2) and a third functional layer (3) stacked from top to bottom. The upper surface of the third functional layer (3) is provided with a rotating shaft (31). The first functional layer (1) is provided with a first axial hole (13) that allows rotation along the rotating shaft (31). The second functional layer (2) is provided with a second axial hole (22) that allows rotation along the rotating shaft (31). The first functional layer (1) is provided with a sample inlet (12), and an adsorption block (14) is provided at the bottom of the first functional layer (1). Adsorption paper is provided on the surface of the adsorption block (14). The second functional layer (2) is provided with a sample receiving groove (23) adapted to the sample inlet (12) and a sample separation and enrichment hole (25) adapted to the adsorption block (14). The sample receiving groove (23) is connected to the sample separation and enrichment hole (25) through a sample flow groove (24). Paper-based carrier sheets for separating samples are arranged crosswise in the sample separation and enrichment hole (25). Filter paper is provided on the surface of the sample receiving groove (23), the sample flow groove (24), and the sample separation and enrichment hole (25). The third functional layer (3) is provided with a sample analysis block (32) adapted to the sample separation and enrichment hole (25). Filter paper is provided on the surface of the sample analysis block (32). The adsorption block (14) is used in conjunction with the adsorption paper to adsorb the impurities remaining after the sample is separated and enriched by the sample separation and enrichment pore (25); the sample analysis block (32) is used in conjunction with the filter paper and the external Raman spectrometer to analyze the components after the sample is separated and enriched by the sample separation and enrichment pore (25) and the filter paper.

2. The three-dimensional paper-based rotating microfluidic device according to claim 1, characterized in that, The first axial hole (13) is located at the center of the first functional layer (1); The sample inlet (12) is provided in a plurality of circumferential directions along the first axial hole (13), and the adsorption block (14) is provided on the side of the sample inlet (12) away from the first axial hole (13), and is provided in a plurality of symmetrical directions along the first axial hole (13).

3. The three-dimensional paper-based rotating microfluidic device according to claim 1, characterized in that, The second axial hole (22) is located at the center of the second functional layer (2); The size of the sample receiving slot (23) is smaller than the size of the sample inlet (12); The paper-based carrier sheet is in the form of a thin, elongated strip.

4. The three-dimensional paper-based rotating microfluidic device according to claim 3, characterized in that, The sample flow groove (24) is located on the side of the sample receiving groove (23) away from the second axial hole (22); the sample separation and enrichment hole (25) is located on the side of the sample flow groove (24) away from the second axial hole (22); Each sample receiving cell (23) is provided with several sample flow channels (24) and sample separation and enrichment holes (25) connected to the several sample flow channels (24); The lower surface of the second functional layer (2) is provided with concentric circular grooves (26) that allow relative movement with the sample analysis block (32).

5. A three-dimensional paper-based rotating microfluidic device according to claim 4, characterized in that, The width of the concentric groove (26) is the maximum outer diameter of the sample separation and enrichment hole (25).

6. A three-dimensional paper-based rotating microfluidic device according to claim 4, characterized in that, The size of the sample analysis block (32) is smaller than the size of the sample separation enrichment well (25).

7. A three-dimensional paper-based rotating microfluidic device according to claim 4, characterized in that, The depth of the sample flow groove (24) gradually increases along the direction of the sample separation and enrichment hole (25) of the sample receiving groove (23).

8. A three-dimensional paper-based rotating microfluidic device according to claim 1, characterized in that, The first functional layer (1) is provided with a first auxiliary moving block (11) at its end, which allows the first functional layer (1) to rotate; The end of the second functional layer (2) is provided with a second auxiliary moving block (21) that allows the second functional layer (2) to rotate.

9. A three-dimensional paper-based rotating microfluidic device according to claim 1, characterized in that, The thickness of the adsorption block (14) is the same as the height of the upper surface of the sample separation and enrichment hole (25) from the upper surface of the second functional layer (2), so as to ensure that the lower surface of the adsorption block (14) can be closely attached to the upper surface of the sample separation and enrichment hole (25).

10. A three-dimensional paper-based rotating microfluidic device according to claim 1, characterized in that, The thickness of the sample analysis block (32) is the same as the height of the lower surface of the sample separation and enrichment hole (25) from the lower surface of the second functional layer (2), so as to ensure that the upper surface of the sample analysis block (32) can be closely attached to the lower surface of the sample separation and enrichment hole (25).

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