Modularized liquid drop one-way self-transportation open channel structure for laser processing and preparation method of modularized liquid drop one-way self-transportation open channel structure

Abstract

The invention discloses a modularized liquid drop one-way self-transportation open channel structure for laser processing and a preparation method, the modularized liquid drop one-way self-transportation open channel structure for laser processing comprises a substrate, the substrate is provided with a micro-channel, the surface of the micro-channel is provided with a periodic micro-groove through laser scanning processing, and the micro-channel is provided with a wedge-shaped cone and a wedge-shaped groove interface; the hydrophobic outer plates are arranged on the two sides of the micro-channel, and hydrophobic coatings are sprayed on the surfaces of the hydrophobic outer plates; the modularized liquid drop one-way self-transportation open channel structure is used for achieving one-way self-transportation of water, an aqueous solution and organic liquid drops, and the transportation direction is that the water, the aqueous solution and the organic liquid drops flow from the wedge-shaped cone to the wedge-shaped groove connector through the micro-channel. The preparation method is accurate and controllable, the cost is low, the designed modularized open channel structure can achieve one-way self-transportation of water, water solutions and even organic liquid drops, real-time assembly, disassembly and repeated use can be conveniently carried out, the switchable self-defined function is achieved, and the application range is wide. Comprising but not limited to straight transportation, in-situ steering, accurate shunting and confluence reaction, and is wide in application range and high in flexibility.

Description

Technical Field

[0001] The present invention belongs to the technical field of laser cutting, laser processing of material surface and micro-droplet transport, and more specifically, the present invention relates to a laser-processed modular droplet unidirectional self-transport open channel structure and a preparation method thereof. Background Art

[0002] In the fields of biomedicine, chemical processes, etc., mixing, separating and transporting tiny droplets usually results in unnecessary sample loss, increased experimental costs, and considerable economic losses. How to achieve low-energy, pollution-free, and precisely controllable micro-droplet transportation has become a focus of attention. Existing droplet manipulation schemes actively manipulate droplets by applying an external field, but these technologies require complex external energy equipment and generally have disadvantages such as contaminating samples and high energy consumption.

[0003] The construction of unique structures through cutting-edge biomimetic designs to achieve droplet self-transportation is gradually gaining more and more attention. However, the existing droplet self-transportation schemes are usually only able to transport droplets in fixed modes and paths because of their fixed structures and lack of scalability. It is difficult to achieve in-situ programmable and customizable functions and cannot adapt to actual working conditions. Therefore, it is still a challenge to design a droplet unidirectional self-transportation scheme with high flexibility and field reconfigurability. Summary of the invention

[0004] An object of the present invention is to solve at least the above problems and / or disadvantages and to provide at least the advantages which will be described hereinafter.

[0005] In order to achieve these purposes and other advantages according to the present invention, a method for preparing a laser-processed modular droplet unidirectional self-transport open channel structure is provided, comprising the following steps:

[0006] S1. Use a hydrophobic coating to spray and modify the surface of a substrate made of high borosilicate glass, spray a hydrophobic coating on the upper and lower surfaces of the substrate to obtain double-sided super hydrophobicity;

[0007] S2, using a femtosecond laser to scan lines on the substrate hydrophobically modified by S1, removing the hydrophobic coating in a limited area, and constructing periodic micro grooves showing super-hydrophilicity. The laser beam of the femtosecond laser is perpendicular to the substrate surface, and the laser beam scans lines on the substrate surface in a parallel manner;

[0008] S3. Use a femtosecond laser to cut the substrate after the S2 scanning line treatment to construct a wedge-shaped cone-wedge-shaped groove interface and a streamlined outer contour to obtain a modular droplet unidirectional self-transport open channel structure.

[0009] Preferably, in said S1, the hydrophobic coating is a glaco reagent with a model number of SF-04146.

[0010] Preferably, in S2, the diameter of the femtosecond laser spot is 25-30 μm, the scanning pulse energy is 60-120 mW, the scanning rate is 2-8 mm / s, the scanning interval is 20-40 μm, and the number of scanning times is 2 times.

[0011] Preferably, in said S3, the diameter of the femtosecond laser spot used is 25-30 μm, the pulse energy used for cutting is 280-340 mW, the cutting rate is 300-400 μm / s, and the number of cutting times is 3 times.

[0012] A laser-processed modular droplet unidirectional self-transport open channel structure, comprising:

[0013] A substrate is provided with a microchannel, the surface of the microchannel is processed with periodic microgrooves by laser scanning, one end of the microchannel is cut with at least one wedge-shaped cone by laser, and the other end of the microchannel is cut with at least one wedge-shaped groove interface adapted to the wedge-shaped cone by laser; wherein the laser scanning direction is parallel scanning from the wedge-shaped cone to the wedge-shaped groove interface line by line; the periodic microgrooves include a plurality of microgrooves, each of which is obtained by laser scanning;

[0014] A hydrophobic outer plate, which is arranged on both sides of the microchannel, and the surface of the hydrophobic outer plate is sprayed with a hydrophobic coating;

[0015] The modular droplet unidirectional self-transport open channel structure is used to realize the unidirectional self-transport of water, aqueous solution and organic droplets. The transport direction is from the wedge-shaped cone to the wedge-shaped groove interface through the microchannel.

[0016] Preferably, the substrate is made of high-boron glass, and the thickness of the substrate is 130-170 μm.

[0017] Preferably, the wedge angles of the wedge-shaped cone and the wedge-shaped groove interface are both 20°; the span of the wedge-shaped groove interface is 1.05 mm, and the distance between two adjacent periodic micro-grooves is 25-30 μm.

[0018] Preferably, the static contact angle of water on the surface of the periodic micro-grooves is less than 10°, and the static contact angle of water on the hydrophobic layer on the surface of the hydrophobic outer plate is greater than 150°.

[0019] Preferably, the modular droplet unidirectional self-transport open channel structure is configured as a straight-moving module, a merging module, a diversion module, a right-turning module, a left-turning module or a collecting module;

[0020] The straight-moving module includes a wedge-shaped vertebra and a wedge-shaped slot interface, wherein the wedge-shaped vertebra and the wedge-shaped slot interface are arranged in a straight line;

[0021] The confluence module includes two wedge-shaped vertebrae and a wedge-shaped groove interface, wherein the two wedge-shaped vertebrae are arranged in a straight line, the wedge-shaped groove interface is located in the middle of the microchannel, and the angle between the wedge-shaped groove interface and the two wedge-shaped vertebrae is 90°;

[0022] The flow splitting module includes a wedge-shaped cone and two wedge-shaped groove interfaces, wherein the two wedge-shaped groove interfaces are arranged in a straight line, the wedge-shaped cone is located in the middle of the microchannel, and the angle between the wedge-shaped cone and the two wedge-shaped groove interfaces is 90°;

[0023] The right-turn module and the left-turn module include a wedge-shaped vertebra and a wedge-shaped groove interface, and the angle between the wedge-shaped vertebra and the wedge-shaped groove is 90°;

[0024] The collecting module is provided with a wedge-shaped cone and a square collecting area.

[0025] Preferably, the outer edge of the hydrophobic outer plate is cut into a streamlined shape by laser.

[0026] The present invention has at least the following beneficial effects:

[0027] 1. In the modular open channel structure for unidirectional self-transport of droplets disclosed in the present invention, the periodic micro-groove structure exhibits super-hydrophilicity and forms patterned wettability with the super-hydrophobic area of ​​the unprocessed area. By designing a high-resolution patterned wettability surface, ultrafast self-transport of droplets on a single channel structure is achieved. By utilizing the unidirectional transport law of droplets flowing from the wedge-shaped cone of one module to the wedge-shaped groove and then to the wedge-shaped cone of the next module, continuous unidirectional self-transport of droplets across discontinuous channels is further achieved, thereby achieving low-energy consumption and high-flexibility unidirectional self-transport of droplets.

[0028] 2. The present invention is simple to prepare, easy to operate, and low in cost. It can realize integrated self-transportation of droplets and can adapt to working conditions including pure water, aqueous solutions and even some organic liquids. The maximum transport speed of droplets on a single module can reach 480 mm / s, the normalized transport distance can reach 56.32, the loss rate of transported droplets can be as low as 4.8%, and the flow range that can be adapted is 5 to 30 μL / min. Through the on-demand combination of modules such as straight, turning, diversion, and confluence, multiple functions such as continuous long-distance transport of droplets, precise diversion supply, and confluence microchemical reactions can be realized. The structure can also provide a higher specific surface area, and has important application value in microchemical reactions requiring the participation of liquid-gas interfaces, component detection and tracing, etc.

[0029] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a flow chart of the preparation of the modular droplet unidirectional self-transport open channel structure of the present invention; Figure 2 This is a schematic diagram of the modular droplet unidirectional self-transport open channel structure in Example 1 of the present invention; Figure 3 Schematic diagram of the modular droplet unidirectional self-transport open channel structure of the present invention, from A to F are a straight module, a merging module, a diversion module, a right turn module, a left turn module and a collection module; Figure 4 It is a unidirectional transport performance diagram of the modular droplet unidirectional self-transport open channel structure of the present invention; Figure 5 It is a normalized transport performance diagram of the modular droplet unidirectional self-transport open channel structure of the present invention; Figure 6 It is a low loss rate characteristic diagram of the modular droplet unidirectional self-transport open channel structure of the present invention; Figure 7 A field-customizable path map for the modular open channel structure for one-way self-transport of droplets of the present invention; Figure 8 A diagram showing the control of the confluence color reaction of the modularized droplet unidirectional self-transport open channel structure of the present invention; Fig. 9 This is a diagram of the directional transport control of ethylene glycol in the modular open channel structure of droplet unidirectional self-transport of the present invention; Fig.10 This is a self-transportation performance diagram of a rectangular interface modular channel of Comparative Example 1 of the present invention; Fig.11 This is a self-transportation performance diagram of the arc-shaped interface modular channel of Comparative Example 2 of the present invention; Fig.12 This is a data diagram of the droplet self-transport performance of Comparative Examples 1-2 and Example 1. DETAILED DESCRIPTION

[0042] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0043] It should be understood that the terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0044] The present invention uses femtosecond laser processing combined with spraying modification to process a one-way self-transport open channel for droplets on a high-boron glass substrate (see Figure 1 ), including using commercial hydrophobic modification reagent glaco (brand is SOFT99, model is SF-04146) to spray the substrate surface to obtain super hydrophobicity, using femtosecond laser line scanning method to construct super hydrophilic periodic micro grooves on the substrate surface to achieve patterned wettability, and using femtosecond laser to cut a uniform wedge-shaped cone-wedge-shaped groove interface to obtain a modular droplet unidirectional self-transport open channel structure, which specifically includes a straight module, a confluence module, a diversion module, a left turn module, a right turn module and a collection module (see Figure 3 );

[0045] Among them, the high borosilicate glass sheet has a thickness of about 130 to 170 μm; the wedge angle of the wedge-shaped vertebra-groove interface is uniformly 20°, and the interface span is 1.05 mm; the microgroove structure in the droplet self-transport channel is of the same size, and the center spacing is 30 μm.

[0046] The specific scheme proposed by the present invention is described in more detail with reference to several specific embodiments below.

[0047] Embodiment 1:

[0048] like Figure 1 and Figure 2 As shown, this embodiment provides a laser-processed modular droplet unidirectional self-transport open channel structure, including:

[0049] A substrate, on which a microchannel is arranged, wherein the surface of the microchannel is processed with periodic microgrooves by laser scanning, wherein the direction of the laser scanning is scanning in parallel from a wedge-shaped vertebra to a wedge-shaped groove interface line by line, wherein a wedge-shaped vertebra is cut at one end of the microchannel by laser, and a wedge-shaped groove interface adapted to the wedge-shaped vertebra is cut at the other end of the microchannel by laser; wherein the direction of the laser scanning is scanning in parallel from a wedge-shaped vertebra to a wedge-shaped groove interface line by line; wherein the periodic microgrooves include a plurality of microgrooves, each of which is obtained by laser scanning;

[0050] A hydrophobic outer plate, which is arranged on both sides of the microchannel, and the surface of the hydrophobic outer plate is sprayed with a hydrophobic coating;

[0051] The modular droplet unidirectional self-transport open channel structure is used to realize the unidirectional self-transport of water, aqueous solution and organic droplets. The transport direction is from the wedge-shaped cone to the wedge-shaped groove interface through the microchannel.

[0052] The substrate is a 150μm thick high-boron glass sheet; it has a wedge-shaped cone-wedge-shaped groove interface to meet the functional requirements of on-demand assembly and disassembly, the wedge angles of the wedge-shaped cone and wedge-shaped groove interface are uniformly 20°, and the span of the wedge-shaped groove interface is 1.05mm; the background area outside the microchannel is superhydrophobic, with a static contact angle of water of 156°, and the inside is a periodic microgroove structure, which is superhydrophilic, with a static contact angle of water of less than 10°, and the center spacing of the periodic microgrooves of the microchannel is 30μm.

[0053] The preparation method of the modular droplet unidirectional self-transport open channel structure comprises the following steps:

[0054] S1. Use a hydrophobic coating to spray and modify the surface of a substrate made of high borosilicate glass, spray a hydrophobic coating on the upper and lower surfaces of the substrate to obtain double-sided super hydrophobicity;

[0055] S2, using a femtosecond laser to scan lines on the substrate hydrophobically modified by S1, remove the hydrophobic coating in a limited area, and construct periodic micro grooves showing super-hydrophilicity. The laser beam of the femtosecond laser is perpendicular to the substrate surface, and the laser beam scans the substrate surface in a parallel manner; the femtosecond laser spot diameter is 27μm, the scanning pulse energy is 80mW, the scanning rate is 5mm / s, the scanning interval is 30μm, and the number of scanning times is 2 times;

[0056] S3. Use a femtosecond laser to cut the substrate after the S2 scanning line treatment. The femtosecond laser spot diameter used is 27μm, the pulse energy used for cutting is 300mW, the cutting rate is 300μm / s, the number of cuttings is 3 times, and a wedge-shaped cone-wedge-shaped groove interface and a streamlined outer contour are constructed to obtain a modular droplet unidirectional self-transport open channel structure.

[0057] See also Figure 4In order to verify the unidirectional performance of the modular droplet unidirectional self-transport open channel structure, three straight modules were connected from left to right with groove cones for series assembly, wherein the straight module included a wedge-shaped cone and a wedge-shaped groove interface, wherein the wedge-shaped cone and the wedge-shaped groove interface were arranged in a straight line, that is, in two adjacent straight modules, the wedge-shaped cone of one straight module was embedded in the wedge-shaped groove interface of the other straight module, thereby realizing the series assembly of two straight modules; a micro-liquid inlet was used to drip water droplets from above the straight module in the middle position, and the water droplets were pre-dyed with bright blue for easy observation. The water droplets quickly spread out in the middle module within 0.05s, and completed spontaneous continuous transport to the right module after 1.06s. Even if the dripping continued, it would not be transported toward the left module, showing excellent unidirectional performance.

[0058] Embodiment 2:

[0059] This embodiment provides a laser-processed modular droplet unidirectional self-transport open channel structure, whose structure and preparation method are the same as those of Example 1.

[0060] See also Figure 5 In order to verify the long-distance self-transport performance of the modular droplet unidirectional self-transport open channel structure prepared in this embodiment, a long-distance straight path was obtained by assembling 10 straight modules in series. A 10μL droplet of water was added from the leftmost module. After the water droplet completed self-transportation, the liquid surface front transport distance was 75.3mm. The calculated normalized transport distance was as high as 56.32, proving that only a very small amount of liquid sample is needed to achieve continuous long-distance self-transportation. The normalized transport distance calculation formula is as follows:

[0061] D=d / r0

[0062] Where D is the normalized transport distance, d is the transport distance of the front edge of the droplet curved liquid surface, r0 is the radius of the droplet. According to the volume-radius relationship of an ideal sphere, it is estimated that r0 = 1.337 mm.

[0063] Embodiment 3:

[0064] This embodiment provides a laser-processed modular droplet unidirectional self-transport open channel structure, whose structure and preparation method are the same as those of Example 1.

[0065] In this embodiment, a collection module is also used. The collection module is configured to include a wedge-shaped cone and a square collection area, wherein the processing method of the square collection area is the same as the processing method of the microchannel in Example 1.

[0066] See also Figure 6In order to explore the loss rate index of the modular droplet unidirectional self-transport open channel structure when transporting droplets, a droplet straight collection path was assembled through 4 straight modules and 1 collection module. Water droplets were added drop by drop from the leftmost module, and the mass of each module was collected by a precision balance to obtain the proportion of water droplets on the collection module. When the total volume of the added water droplets exceeded 100μL, the volume of water droplets on the collection module exceeded 95.2%, and the droplet loss rate along the straight path was as low as 4.8%. The calculation formula is as follows:

[0067] L=(m3-m1) / (m4-m2+m3-m1)×100%

[0068] Where L is the loss rate along the way, m1 is the initial total mass of the four straight modules, m2 is the initial mass of the collection module, m3 is the total mass of the four straight modules after the transportation is completed, and m4 is the mass of the collection module after the transportation is completed.

[0069] Embodiment 4:

[0070] The present embodiment provides a laser-processed modular droplet unidirectional self-transport open channel structure, which uses a straight module, a merging module, a left-turn module, and a right-turn module, wherein the merging module is configured as two wedge-shaped vertebrae and a wedge-shaped groove interface, wherein the two wedge-shaped vertebrae are arranged in a straight line, the wedge-shaped groove interface is located in the middle of the microchannel, and the angle between the wedge-shaped groove interface and the two wedge-shaped vertebrae is 90°; the right-turn module and the left-turn module include a wedge-shaped vertebra and a wedge-shaped groove interface, and the angle between the wedge-shaped vertebra and the wedge groove is 90°.

[0071] See also Figure 7 In order to verify the path customization and on-site editable functions of the modular droplet unidirectional self-transport open channel structure, the letter "a" path was obtained by combining 1 confluence module and 3 left-turn modules, the letter "b" path was obtained by combining 1 confluence, 1 straight and 3 right-turn modules, the letter "c" path was obtained by combining 3 left-turn modules, and the letter "d" path was obtained by combining 2 confluences, 1 straight and 2 left-turn modules. The water droplets dyed with bright blue spontaneously completed the transport on the patterned path in the direction of the blue arrow, confirming the excellent assembly and disassembly functions and path customization capabilities.

[0072] Embodiment 5:

[0073] This embodiment provides a modular open channel structure for unidirectional self-transport of droplets, and its structure and preparation method are the same as those in Embodiment 1.

[0074] See also Figure 8In order to verify the adaptability of the modular droplet unidirectional self-transport open channel structure to different droplets, a confluence reaction path was assembled through 9 straight modules, 1 confluence module and 1 collection module. The sodium nitrite solution dyed with brilliant blue was dripped from inlet 1 and first spontaneously transported to the collection module. Then, p-aminobenzenesulfonic acid dyed with riboflavin was dripped from inlet 2, and it merged with sodium nitrite in the confluence module and reacted to produce rose red phenomenon. No obvious reflux diffusion of liquids of different colors was observed. Fig. 9 As shown, a U-shaped path was assembled by four right-turning modules, and ethylene glycol dyed with carmine spontaneously completed clockwise transport on the U-shaped path, confirming the wide applicability of the modular open channel structure for unidirectional self-transport of droplets to water, aqueous solutions and even some organic droplets.

[0075] Through the verification of the above-mentioned Examples 1 to 5, Examples 1 to 3 confirmed the capabilities of directional, long-distance and low-loss, with the maximum normalized transport distance reaching 56.32 and the loss rate as low as 4.8%; Examples 4 to 5 confirmed the capabilities of on-site assembly and disassembly and customized paths as needed, which can meet the one-way self-transportation requirements of water, aqueous solutions and some organic droplets; it shows that the present invention can simultaneously possess the functions of low energy consumption, reconfigurability and high efficiency and controllability, and has important application value in the fields of component detection, chemical processes and the like.

[0076] In order to better illustrate the beneficial effects achieved by the modular open channel structure for unidirectional self-transport of droplets and the preparation method of the present invention, the technical solution of the present invention is further analyzed with several comparative examples below.

[0077] Comparative Example 1:

[0078] This comparative example provides a modular droplet unidirectional self-transport open channel structure. The difference between this comparative example and Example 1 is that the wedge-shaped groove interface in Example 1 is changed to a rectangular interface, and the wedge-shaped cone is changed to a rectangular connecting block adapted to the rectangular interface. Fig.10 .

[0079] Comparative Example 2:

[0080] This comparative example provides a modular droplet unidirectional self-transport open channel structure. The difference between this comparative example and Example 1 is that the wedge-shaped groove interface in Example 1 is changed to an arc-shaped interface, and the wedge-shaped cone is changed to an arc-shaped connecting block adapted to the arc-shaped interface. Fig.11 .

[0081] In comparative example 1, water drops are dripped from the middle rectangular interface module at the same flow rate, and the water drops first complete the unidirectional transport to the right module, but after continuing to drip, the water drops will break through the left side and produce bidirectional transport. In comparative example 2, the water drops dripped on the middle arc-shaped interface module cannot be transported to the series modules on the left and right sides at all, showing the phenomenon of bidirectional pinning.

[0082] See also Fig.12 , verified by the above-mentioned Comparative Examples 1-2 and Example 1: the modular droplet unidirectional self-transport open channel structure provided by the present invention has an optimal unidirectional transport range of 0.1-0.9 mm, which is twice that of the modular channel with a rectangular interface and four times that of the modular channel with a circular arc interface, indicating that: the present invention not only successfully completes the modularization of the droplet self-transport channel, but also ensures excellent unidirectional performance, and at the same time can realize the assembly, disassembly and custom design of any complex path on the plane, effectively combining the low energy consumption advantage of the droplet self-transport solution and the flexibility advantage of external field control, and can meet the actual needs of micro-droplet control.

[0083] The number of devices and processing scales described here are used to simplify the description of the present invention. Applications, modifications and variations of the present invention will be obvious to those skilled in the art.

[0084] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A method for preparing a laser-processed modular droplet unidirectional self-transport open channel structure, characterized in that: The following steps are involved: S1. Use a hydrophobic coating to spray and modify the surface of a substrate made of high borosilicate glass, spray a hydrophobic coating on the upper and lower surfaces of the substrate to obtain double-sided super hydrophobicity; S2, using a femtosecond laser to scan lines on the substrate hydrophobically modified by S1, removing the hydrophobic coating in a limited area, and constructing periodic micro grooves showing super-hydrophilicity. The laser beam of the femtosecond laser is perpendicular to the substrate surface, and the laser beam scans lines on the substrate surface in a parallel manner; S3. Use a femtosecond laser to cut the substrate after the S2 scanning line treatment to construct a wedge-shaped cone-wedge-shaped groove interface and a streamlined outer contour to obtain a modular droplet unidirectional self-transport open channel structure.

2. The method for preparing a modular droplet unidirectional self-transport open channel structure by laser processing according to claim 1, characterized in that: In the S1, the hydrophobic coating is a glaco reagent with a model number of SF-04146.

3. The method for preparing a laser-processed modular droplet unidirectional self-transport open channel structure according to claim 1, characterized in that: In S2, the diameter of the femtosecond laser spot is 25-30 μm, the scanning pulse energy is 60-120 mW, the scanning rate is 2-8 mm / s, the scanning interval is 20-40 μm, and the number of scanning times is 2 times.

4. The method for preparing a laser-processed modular droplet unidirectional self-transport open channel structure according to claim 1, characterized in that: In S3, the diameter of the femtosecond laser spot used is 25-30 μm, the pulse energy used for cutting is 280-340 mW, the cutting rate is 300-400 μm / s, and the number of cutting times is 3 times.

5. A laser-processed modular droplet unidirectional self-transport open channel structure, which is prepared by the preparation method of the laser-processed modular droplet unidirectional self-transport open channel structure according to any one of claims 1 to 4, characterized in that: include: A substrate is provided with a microchannel, the surface of the microchannel is processed with periodic microgrooves by laser scanning, one end of the microchannel is cut with at least one wedge-shaped cone by laser, and the other end of the microchannel is cut with at least one wedge-shaped groove interface adapted to the wedge-shaped cone by laser; wherein the laser scanning direction is parallel scanning from the wedge-shaped cone to the wedge-shaped groove interface line by line; the periodic microgrooves include a plurality of microgrooves, each of which is obtained by laser scanning; A hydrophobic outer plate, which is arranged on both sides of the microchannel, and the surface of the hydrophobic outer plate is sprayed with a hydrophobic coating; The modular droplet unidirectional self-transport open channel structure is used to realize the unidirectional self-transport of water, aqueous solution and organic droplets. The transport direction is from the wedge-shaped cone to the wedge-shaped groove interface through the microchannel.

6. The laser-processed modular droplet unidirectional self-transport open channel structure according to claim 5, characterized in that: The substrate is made of high-boron glass, and the thickness of the substrate is 130-170 μm.

7. The laser-processed modular droplet unidirectional self-transport open channel structure according to claim 5, characterized in that: The wedge angles of the wedge-shaped cone and the wedge-shaped groove interface are both 20°; the span of the wedge-shaped groove interface is 1.05 mm, and the distance between two adjacent periodic micro-grooves is 25-30 μm.

8. The laser-processed modular droplet unidirectional self-transport open channel structure according to claim 5, characterized in that: The static contact angle of water on the surface of the periodic micro-grooves is less than 10°, and the static contact angle of water on the hydrophobic layer on the surface of the hydrophobic outer plate is greater than 150°.

9. The laser-processed modular droplet unidirectional self-transport open channel structure according to claim 5, characterized in that: The modular droplet unidirectional self-transport open channel structure is configured as a straight-moving module, a merging module, a diversion module, a right-turning module, a left-turning module or a collecting module; The straight-moving module includes a wedge-shaped vertebra and a wedge-shaped slot interface, wherein the wedge-shaped vertebra and the wedge-shaped slot interface are arranged in a straight line; The confluence module includes two wedge-shaped vertebrae and a wedge-shaped groove interface, wherein the two wedge-shaped vertebrae are arranged in a straight line, the wedge-shaped groove interface is located in the middle of the microchannel, and the angle between the wedge-shaped groove interface and the two wedge-shaped vertebrae is 90°; The flow splitting module includes a wedge-shaped cone and two wedge-shaped groove interfaces, wherein the two wedge-shaped groove interfaces are arranged in a straight line, the wedge-shaped cone is located in the middle of the microchannel, and the angle between the wedge-shaped cone and the two wedge-shaped groove interfaces is 90°; The right-turn module and the left-turn module include a wedge-shaped vertebra and a wedge-shaped groove interface, and the angle between the wedge-shaped vertebra and the wedge-shaped groove is 90°; The collecting module is provided with a wedge-shaped cone and a square collecting area.

10. The laser-processed modular droplet unidirectional self-transport open channel structure according to claim 5, characterized in that: The outer edge of the hydrophobic outer plate is cut into a streamlined shape by laser.

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