Method for manufacturing micro-nano spray needle by pouring deposition self-sealing method and spray needle

Abstract

The invention discloses a method for manufacturing a micro-nano spray needle by a pouring deposition self-sealing method and the spray needle. The manufacturing method comprises the following steps: preparing an unbonded biological vein spray needle and a spray needle cover plate; the biological bristle vein micro-nano structure is re-carved through a pouring method to manufacture a biological vein micro-nano spray needle base plate, a polymer is deposited on the biological vein micro-nano spray needle base plate through a polymer deposition method, a biological vein spray needle nano channel is formed in a self-closing mode, and an unbonded biological vein spray needle is obtained; pouring the spray needle cover plate mold to obtain a spray needle cover plate; and aligning and bonding the unbonded biological vein spray needle and the spray needle cover plate to obtain the micro-nano spray needle. The invention discloses a method for manufacturing a micro-nano spray needle through a pouring deposition self-sealing method and the spray needle. The method comprises the following steps: copying a biological seta vein micro-nano structure through a pouring method to obtain a micro-nano cross-scale spray needle nano channel; obtaining a spray needle nano channel by using a polymer deposition method; a micro-nano channel of the biological vein spray needle is sealed through an oxygen plasma auxiliary bonding method, and the micro-nano spray needle is obtained.

Description

Technical Field

[0001] The invention relates to the field of micro-electromechanical technology, and in particular to a method for manufacturing a micro-nano spray needle by a casting deposition self-sealing method and the spray needle. Background Art

[0002] Electrojet printing is an additive manufacturing technology based on the electrohydrodynamic effect. A strong electric field is formed by applying a high voltage power supply between the nozzle and the substrate. The liquid forms a Taylor cone under the action of the electric field force. When the electric field force overcomes the surface tension and viscosity of the liquid, the liquid is ejected from the nozzle to form a stable and fine jet, realizing printing and manufacturing at the micro-nano scale. In view of the scale effect of printing technology, achieving higher resolution printing graphics mainly depends on reducing the inner diameter of the nozzle. Therefore, the current focus is on developing nano-needle preparation methods to increase the printing resolution to the nanometer level.

[0003] The nanochannel of the nozzle is the core structure of the micro-nano nozzle. Although existing nanofabrication technologies can produce nanochannels with high precision and quality, these technologies usually rely on expensive processing equipment. They are limited by the processing characteristics of sequential execution and time consumption, which not only reduces production efficiency, prolongs the overall manufacturing cycle, but also increases the processing and manufacturing costs. Summary of the invention

[0004] The present invention overcomes the shortcomings of the prior art and provides a method and a nozzle for manufacturing a micro-nano nozzle by a casting deposition self-sealing method. The micro-nano structure of biological bristle veins is replicated by a casting method to obtain a micro-nano cross-scale nozzle needle nanochannel; a polymer deposition method is used to obtain a nozzle needle nanochannel; and finally, an oxygen plasma-assisted bonding method is used to seal the biological vein nozzle needle micro-nano channel to obtain a complete micro-nano nozzle.

[0005] To achieve the above object, the technical solution adopted by the present invention is: a method for manufacturing a micro-nano spray needle by a casting deposition self-sealing method, comprising the following steps: Step S1, preparing an unbonded biological venous spray needle and a spray needle cover plate, and proceeding to step S2; The method for preparing the unbonded biological venous spray needle comprises the following steps: Step S1.1, using a casting method to replicate the biological bristle vascular micro-nano structure to manufacture a biological vascular micro-nano spray needle substrate: Step S1.2, using a polymer deposition method to deposit a polymer deposition layer on the inner wall of the micro-nano channel of the biological venous micro-nano spray needle substrate to form a biological venous spray needle nanochannel to obtain an unbonded biological venous spray needle; The preparation method of the spray needle cover plate comprises the following steps: The nozzle cover plate is obtained by pouring the nozzle cover plate mold; Step S2, respectively subjecting the unbonded biological venous spray needle and the spray needle cover plate to oxygen plasma treatment, and then proceeding to step S3; Step S3, aligning and bonding the unbonded biological venous spray needle and the spray needle cover plate after the treatment in step S2, sealing the unbonded biological venous spray needle, forming a biological venous spray needle micro-nano channel, and obtaining a micro-nano spray needle.

[0006] In a preferred embodiment of the present invention, the step of obtaining the biological vascular micro-nano spray needle substrate comprises: Step S1.1.1, obtaining an organism having a biological bristle vein micro-nano structure, and purifying, drying, and hydrophobicizing the organism; Step S1.1.2, spreading the purified and dried organism on a PMMA substrate, pouring a PDMS curing agent mixed solution onto the organism on the PMMA substrate and curing it, separating the cured PDMS from the organism, and obtaining a biological vascular micro-nano spray needle substrate.

[0007] In a preferred embodiment of the present invention, the method for preparing the spray needle cover plate mold comprises the following steps: exposing and developing the treated thermal curing photoresist through a mask using a photolithography machine to obtain the spray needle cover plate mold; The nozzle cover plate is obtained by pouring the nozzle cover plate mold, which includes the following steps: pouring a PDMS curing agent mixed solution into the nozzle cover plate mold and curing it, separating the cured PDMS solid body from the PMMA substrate, and using the separated PDMS solid body as the nozzle cover plate.

[0008] In a preferred embodiment of the present invention, the organism is an organism in the order Diptera of the order Arachnid or Insecta, and the biological bristle vein micro-nanostructure is the leg bristles of the organism in the order Diptera of the order Arachnid or Insecta.

[0009] In a preferred embodiment of the present invention, purifying, drying and hydrophobizing the organism comprises: The organisms were ultrasonically cleaned with deionized water for 5-25 min, with an ultrasonic power of 50-90 W and a temperature of 21-27 °C; Repeat ultrasonic cleaning for 3 times, finally use a nitrogen air gun to blow dry and place on a 40~50℃ hot plate or oven for 30~60min to remove moisture; Drop 1-5 ml of trimethylsilyl chloride into the drying tower, seal it for 5-10 minutes, then place the organism into the drying tower filled with trimethylsilyl chloride and perform hydrophobic treatment for 10-20 minutes; And / or, the step of pouring the PDMS curing agent mixed solution onto the organism on the PMMA substrate and curing the mixture comprises: The treated organism is fixed flat on a PMMA substrate, and the PDMS curing agent mixed solution is poured onto the organism, which is then placed in a vacuum environment below 10Pa for 0.5 to 2 hours; then placed on a horizontal stationary table and cured at room temperature for 20 to 28 hours; The steps to separate the cured PDMS from the organism include: The solidified PDMS is separated from the organism to obtain a PDMS micro-nano mold; the PDMS micro-nano mold is placed in deionized water for ultrasonic cleaning for 0.5 to 2 hours to remove the bristles remaining on the PDMS micro-nano mold during the demolding process. During the ultrasonic cleaning process, the structure should be kept facing downward to make it easier for the bristles to detach from the PDMS micro-nano mold. The ultrasonic power is 100W to 300W, the ultrasonic time is 30 to 60 minutes, and the ultrasonic treatment is repeated 3 times; the PDMS micro-nano mold after ultrasonic cleaning is blown dry with a nitrogen air gun and placed on a hot plate at 80 to 100°C for 10 to 30 minutes to remove moisture from the PDMS micro-nano mold to obtain a biological vascular micro-nano spray needle substrate.

[0010] In a preferred embodiment of the present invention, the polymer deposition method comprises the following steps: The biological ventricle micro-nano spray needle substrate is placed in an oxygen plasma ashing instrument for oxygen plasma treatment, with a treatment power of 20-30 W and a treatment time of 15-30 s; the biological ventricle micro-nano spray needle substrate after oxygen plasma treatment is placed in a Parylene deposition chamber with the structure facing upward; 0.05-0.15 g of Parylene is used for thin film growth, wherein the deposition pressure is 20-60 mTorr, and the Parylene film growth method is used to shrink the micro-nano channel of the biological ventricle micro-nano spray needle substrate, and a Parylene film is generated on the surface of the micro-nano channel of the biological ventricle micro-nano spray needle substrate, which is self-sealed to obtain a spray needle nanochannel below 100 nm.

[0011] In a preferred embodiment of the present invention, the process of obtaining the nozzle cover plate by pouring the nozzle cover plate mold comprises the following steps: Spin-coat a layer of photoresist on the silicon wafer, wherein the low-speed spin-coating speed is 600~900rpm and the high-speed spin-coating speed is 1500~5000rpm; Place the silicon wafer with the photoresist spin-coated on a horizontal hot plate and pre-bake for 30-40 minutes at a temperature of 80-90°C. The silicon wafer with the photoresist spun on it after pre-baking is placed under the photolithography machine, and the mask is placed. The photoresist is exposed to ultraviolet light through the mask, and the exposure time is 30-70s. After exposure, develop in AZ series developer for 30-50 seconds to remove the exposed photoresist, and then rinse in deionized water for 30-50 seconds to obtain a photoresist step with a width of 50 μm; Blow dry with a nitrogen air gun, place on a high-temperature hot plate at 150-200°C and bake for 20-30 minutes, the photoresist step gradually changes from a rectangular step to a semicircular shape; then cool to room temperature with the plate to obtain a needle cover plate mold; 1-5 ml of trimethylchlorosilane (TMCS) is dripped into the drying tower and sealed for 5-10 minutes; the spray needle cover plate mold is placed in the drying tower filled with trimethylchlorosilane atmosphere for 10-20 minutes for hydrophobic treatment, so that an anti-adhesion layer is formed on the surface of the spray needle cover plate mold; Pour a PDMS mixed solution with a ratio of 4:1 to 8:1 onto the needle cover plate mold, and then place it in a vacuum environment for 1 to 2 hours to allow the PDMS mixed solution to completely fill the needle cover plate mold pattern; Place the needle cover plate mold poured with the PDMS mixed solution on a horizontal platform and let it stand for 10-20 minutes, then bake it in an oven at 60-80°C for 2-4 hours to solidify the PDMS mixed solution; The solidified PDMS is separated from the needle cover plate mold, and the needle cover plate with connecting channels is then obtained.

[0012] In a preferred embodiment of the present invention, in step 3, the unbonded biological venous spray needle and the spray needle cover plate after the treatment in step 2 are aligned and bonded, the unbonded biological venous spray needle is sealed, the biological venous spray needle micro-nano channel is formed, and the micro-nano spray needle is obtained: Before bonding, the biological vein spray needle and the spray needle cover plate were treated with oxygen plasma at a treatment power of 20-30W and a treatment time of 10-30s; A hydrophilic treated steel needle with a diameter of 60 μm is inserted into a short channel with a diameter of 50 μm between the bonded biological venous spray needle and the spray needle cover plate for interference fit to obtain a micro-nano spray needle.

[0013] In a preferred embodiment of the present invention, the hydrophobic treatment of the organism comprises: dripping 1-5 ml of trimethylchlorosilane into a sealed drying tower, volatilizing for 5-10 minutes, and vertically placing the spider leg into a sealed drying tower with trimethylchlorosilane atmosphere for atmosphere treatment for 10-20 minutes; And / or, the photoresist is a positive photoresist, and the developer is a positive photoresist developer; or, the photoresist is a negative photoresist, and the developer is a negative photoresist developer; and / or, the PDMS curing temperature is 80°C to 60°C, and the curing time is 2h to 4h; And / or, the ratio of PDMS to curing agent in the PDMS-curing agent mixed solution is 4:1 to 8:1.

[0014] In a preferred embodiment of the present invention, a casting deposition self-sealing method is used to manufacture a micro-nano spray needle, which is characterized in that the spray needle is prepared by using the casting deposition self-sealing method to manufacture a micro-nano spray needle.

[0015] The present invention solves the defects existing in the technical background, and the beneficial technical effects of the present invention are: The invention discloses a method for manufacturing a micro-nano spray needle by a casting deposition self-sealing method and a spray needle, wherein a micro-nano cross-scale spray needle nanochannel is obtained by replicating the micro-nano structure of biological bristle veins by a casting method; a spray needle nanochannel is obtained by a polymer deposition method; and finally, an oxygen plasma-assisted bonding method is used to seal the biological vein spray needle micro-nano channel to obtain a complete micro-nano spray needle.

[0016] 1. The submicron pattern was obtained by replicating the structure of biological bristles through the casting method, and the submicron pattern was reduced to a nano pattern below 100nm by the polymer deposition method, thereby obtaining a self-closed needle nanochannel; after obtaining the micro-nano channel, the submicron structure therein was reduced to a submicron hole by deposition technology, and finally a self-closed nanochannel was formed. The size of the end of the biological bristles is at the submicron level, and the thin film deposition technology can be used to reduce the submicron channel and form a self-closed channel, killing two birds with one stone. The nanochannel has been self-closed, and the channel has become a channel.

[0017] 2. The nozzle cover was manufactured by high-temperature post-baking method, and finally the micro-nano channel of the biological vascular nozzle was sealed by oxygen plasma-assisted bonding method to obtain a polymer micro-nano cross-scale nozzle.

[0018] 3. The technology of the present invention is used to produce micro-nano spray needles, which simplifies the manufacturing process, reduces production costs, and achieves the dual advantages of process simplicity and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0020] Figure 1 It is a manufacturing flow chart of a biological venous micro-nano spray needle substrate based on spider leg bristles in a preferred embodiment of the present invention; Figure 2 It is a manufacturing flow chart of obtaining biological vein spray needle nanochannels in a preferred embodiment of the present invention; Figure 3 is a flow chart of the preparation of the spray needle cover plate in the preferred embodiment of the present invention; Figure 4 It is a flow chart of aligning and keying the biological vein spray needle and the spray needle cover plate in a preferred embodiment of the present invention; Figure 5 is a structural diagram of a micro-nano spray needle in a preferred embodiment of the present invention; Figure 6This is a microscope image of spider leg bristles in the third preferred embodiment of the present invention; Figure 7 This is a SEM image of the biological venation micro-nano spray needle substrate based on spider leg bristles in the third preferred embodiment of the present invention; Figure 8 is a SEM image of the biological venous spray needle nanochannel obtained by the deposition method in the preferred embodiment 3 of the present invention; Fig. 9 is a SEM image of a micron photoresist step obtained after photolithography in the third preferred embodiment of the present invention; Fig.10 This is a SEM image of the photoresist obtained after high-temperature post-baking in the preferred embodiment 3 of the present invention.

[0021] In the figure: 1-spider legs; 2-PDMS cured body; 3-PDMS micro-nano mold; 4-Parylene film; 5-silicon wafer; 6-photoresist; 7-mask; 8-ultraviolet light; 9-spray needle cover mold; 10-PDMS curing agent mixed solution; 11-steel needle. DETAILED DESCRIPTION

[0022] The present invention will now be further described in detail with reference to the accompanying drawings and embodiments. These drawings are simplified schematic diagrams that only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0023] It should be noted that if there are directional indications (such as up, down, bottom, top, etc.) involved in the embodiments of the present invention, the directional indication is only used to explain the relative position relationship, movement, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly. The terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. Unless otherwise clearly specified and defined, the terms "set", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] A method for manufacturing a micro-nano spray needle by a casting deposition self-sealing method comprises the following steps: Step S1, preparing an unbonded biological venous spray needle and a spray needle cover plate, and proceeding to step S2; The method for preparing the unbonded biological venous spray needle comprises the following steps: Step S1.1, using a casting method to replicate the biological bristle vascular micro-nano structure to manufacture a biological vascular micro-nano spray needle substrate.

[0025] The steps for obtaining the biological vascular micro-nano spray needle substrate include: Step S1.1.1, obtaining an organism having a biological bristle vein micro-nano structure, and purifying, drying, and hydrophobicizing the organism; Step S1.1.2, laying the purified and dried organism on a PMMA substrate, pouring a PDMS curing agent mixed solution 10 onto the organism on the PMMA substrate and curing it, separating the cured PDMS from the organism, and obtaining a biological venous micro-nano spray needle substrate; Step S1.2, using a polymer deposition method to deposit a polymer deposition layer on the inner wall of the micro-nano channel of the biological choroid micro-nano spray needle substrate to form a biological choroid spray needle nanochannel and obtain an unbonded biological choroid spray needle.

[0026] The preparation method of the spray needle cover plate comprises the following steps: The nozzle cover plate is obtained by pouring the nozzle cover plate mold 9. The preparation method of the nozzle cover plate mold 9 includes the following steps: the treated heat-cured photoresist 6 is exposed and developed through the mask 7 by a photolithography machine to obtain the nozzle cover plate mold 9. The nozzle cover plate is obtained by pouring the nozzle cover plate mold 9, including the following steps: pouring the PDMS curing agent mixed solution 10 into the nozzle cover plate mold 9 and curing it; separating the cured PDMS solidified body 2 from the PMMA substrate, and using the separated PDMS solidified body 2 as the nozzle cover plate.

[0027] Step S2, respectively subjecting the unbonded biological venous spray needle and the spray needle cover plate to oxygen plasma treatment, and then proceeding to step S3; Step S3, aligning and bonding the unbonded biological venous spray needle and the spray needle cover plate processed in step S2, sealing the unbonded biological venous spray needle, forming a biological venous spray needle micro-nano channel, and obtaining a micro-nano spray needle.

[0028] Specifically, the organism is an organism in the order Arachnid or Diptera of the class Insecta, and the biological bristle vein micro-nano structure is the leg bristles of an organism in the order Arachnid or Diptera of the class Insecta. The organisms in the order Arachnid are for example spiders, and the organisms in the order Diptera of the class Insecta are for example mosquitoes and flies.

[0029] Specifically, the photoresist 6 can be a positive photoresist or a negative photoresist. When a positive photoresist is used, a positive photoresist developer is used as a developer, and when a negative photoresist is used, a negative photoresist developer is used as a developer. The selection of the photoresist 6 will not be listed one by one here, as long as it can basically meet the requirements of photolithography, exposure, and development of the photoresist 6 in this embodiment. Embodiment 1

[0030] like Figure 1-Figure 4 As shown, in this embodiment, the organism used is an organism in the order Arachnids, and the biological bristle vein micro-nano structure is a leg with bristles in the order Arachnids.

[0031] Therefore, a method for manufacturing a micro-nano spray needle by a casting deposition self-sealing method comprises the following steps: Step S1, preparing an unbonded biological venous spray needle and a spray needle cover plate, and proceeding to step S2; The method for preparing the unbonded biological venous spray needle comprises the following steps: Step S1.1, using a casting method to replicate the biological bristle vascular micro-nano structure to manufacture a biological vascular micro-nano spray needle substrate; like Figure 1 As shown, the steps for obtaining the biological vascular micro-nano spray needle substrate include: Step S1.1.1, obtaining an organism having a biological bristle venation micro-nano structure, and purifying, drying, and hydrophobicizing the organism.

[0032] Among them, the purification, drying and hydrophobic treatment of organisms include: like Figure 1 As shown in 1a, the spider leg 1 is ultrasonically cleaned with deionized water for 5 minutes, wherein the ultrasonic power is 50W and the temperature is 21°C; after cleaning and purification, it is blown dry with a nitrogen air gun, ultrasonic cleaning is repeated 3 times, and finally, it is blown dry with a nitrogen air gun and placed in a 40°C oven for 30 minutes to remove moisture, but it is not limited to this. In other embodiments, a hot plate can be used instead of an oven. 1 ml of trimethylchlorosilane (TMCS) is dripped into the drying tower, and after sealing and volatilization for 5 minutes, the spider leg 1 is vertically placed in a sealed drying tower with a trimethylchlorosilane atmosphere for 10 minutes of atmosphere treatment.

[0033] Step S1.1.2, as Figure 1 As shown in Figure 1b, the purified and dried organisms are spread flat on PMMA ( On a polymethyl methacrylate) substrate, a PDMS curing agent mixed solution 10 is poured onto the organism of the PMMA substrate and cured to form a PDMS cured body 2, and the PDMS cured body 2 is cut according to actual needs, and the PDMS cured body 2 is separated from the spider leg 1 to obtain a biological venous micro-nano spray needle substrate. The PDMS curing agent mixed solution 10 is a PDMS and curing agent in a ratio of 4:1. Further, after collecting the spider leg 1, the leg bristles are messy before cleaning. After repeated ultrasonic cleaning, some fragile hairs have fallen off, and most of the remaining bristles are regular. After obtaining the PDMS cured body 2, the nanochannel end is cut, and the port can obtain an array-distributed spray needle port. Furthermore, in order to improve the stability of cutting, the present invention uses a relatively sharp coating knife in the prior art to avoid deformation of the channel caused by a blunt tool. Moreover, when cutting, cut from the back of the channel instead of the front. Cutting from the front of the channel is likely to cause channel deformation.

[0034] Among them, the steps of pouring the PDMS curing agent mixed solution 10 onto the organism of the PMMA substrate and curing it include: the treated spider leg 1 is flatly fixed on the PMMA substrate, the PDMS curing agent mixed solution 10 is poured onto the spider leg 1, and then placed in a vacuum environment below 10Pa and evacuated for 0.5 hours; then placed on a horizontal stationary table and cured at room temperature for 20 hours.

[0035] Among them, the step of separating the solidified PDMS from the organism includes: the solidified PDMS forms a PDMS solid body 2 and is separated from the spider leg 1 to obtain a PDMS micro-nano mold 3; the PDMS micro-nano mold 3 is placed in deionized water for ultrasonic cleaning for 0.5 hours to remove the bristles remaining on the PDMS micro-nano mold 3 during the demolding process. During the ultrasonic cleaning process, the structure should be kept facing down to make it easier for the bristles to detach from the PDMS micro-nano mold 3, wherein the ultrasonic power is 100W and the ultrasonic time is 30 minutes; the PDMS micro-nano mold 3 after ultrasonic cleaning is blown dry with a nitrogen air gun and placed on a hot plate at 80°C for 10 minutes to remove moisture from the PDMS micro-nano mold 3 to obtain a biological vascular micro-nano spray needle substrate.

[0036] Step S1.2, such as Figure 2 As shown, a polymer deposition layer is deposited on the inner wall of the micro-nano channel of the biological venous micro-nano needle substrate by a polymer deposition method to form a biological venous needle nanochannel and obtain an unbonded biological venous needle. The polymer deposition method for growing the Parylene film 4 includes the following steps: Figure 2 As shown in Figure 2a, the biological ventricle micro-nano needle substrate is placed in an oxygen plasma ashing instrument for oxygen plasma treatment, with a treatment power of 20 W and a treatment time of 15 s; Figure 2As shown in 2b, the biological venous micro-nano spray needle substrate treated with oxygen plasma is placed in a Parylene deposition chamber with the structure facing upward; 0.05g of Parylene is used for film growth, wherein the deposition pressure is 20mTorr, and the growing Parylene film 4 is used to shrink the nanochannel of the biological venous micro-nano spray needle substrate, and the Parylene film 4 is generated on the nanochannel surface of the biological venous micro-nano spray needle substrate, as shown in FIG. Figure 2 As shown in Figure 2c, a needle nanochannel with a diameter of less than 100 nm is obtained.

[0037] Specifically, the size of the end of the spider leg 1 is about 200nm, and 100nm and below is called a nanostructure. Above 100nm and below 1um is submicron. After obtaining the micro-nano channel, the submicron structure therein uses deposition technology to shrink the submicron pores, and finally forms a self-closed nanochannel. The size of the bristle end of the spider leg 1 is at the submicron level. Only thin film deposition technology is needed to shrink the submicron channel and form a self-closed channel, killing two birds with one stone. Therefore, there is no need for additional stretching and shrinking to obtain the nanochannel. After deposition, the nanochannel has been self-closed, and the channel has been transformed from a channel. However, the size of the micron channel is relatively too large and has not been self-closed; therefore, the micron channel is still a channel after being treated by the polymer deposition method. Further, after deposition, the micron channel and other planes (all exposed surfaces) will be deposited with a Parylene film 4; finally, the micron channel is shrunk, and the submicron channel therein forms a self-closed nanochannel.

[0038] like Figure 3 As shown, the preparation method of the spray needle cover plate includes the following steps: The spray needle cover plate is obtained by casting the spray needle cover plate mold 9.

[0039] Among them, Figure 3 As shown in 3a, the preparation method of the nozzle cover plate mold 9 includes the following steps: the nozzle cover plate is obtained by pouring the nozzle cover plate mold 9, and the following steps are included: a layer of photoresist 6 is spin-coated on the silicon wafer 5, and the photoresist 6 adopts AZ703 photoresist, wherein the low-speed spin coating speed is 600rpm, and the high-speed spin coating speed is 1500rpm; the silicon wafer 5 spin-coated with the photoresist 6 is placed on a horizontal hot plate for pre-baking for 30 minutes, wherein the pre-baking temperature is 80°C. The treated heat-cured photoresist 6 is exposed and developed through the mask 7 using a photolithography machine. Specifically, the silicon wafer 5 spin-coated with the photoresist 6 after pre-baking is placed under the photolithography machine, the mask 7 is placed, and the ultraviolet light 8 is transmitted through the mask 7 to expose the photoresist 6, wherein the exposure time is 30s; after exposure, it is developed in a developer (AZ series developer) for 30s, as shown Figure 3As shown in 3b, the exposed photoresist 6 is removed, and then placed in deionized water for 30 seconds to obtain a photoresist step with a width of 5 μm; it is blown dry with a nitrogen air gun, placed on a high-temperature hot plate at 150°C and baked for 20 minutes, and the photoresist step gradually changes from a rectangular step to a semicircular shape. Figure 3 As shown in FIG. 3c, the plate is then cooled to room temperature to obtain a spray needle cover plate mold 9.

[0040] The steps of obtaining the needle cover plate by pouring the needle cover plate mold 9 include: pouring the PDMS curing agent mixed solution 10 into the needle cover plate mold 9 and curing it; separating the cured PDMS solid body 2 from the PMMA substrate, and using the separated PDMS solid body 2 as the needle cover plate. Specifically, 1 ml of trimethylchlorosilane (TMCS) is dripped into the drying tower and sealed for 5 minutes; the needle cover plate mold 9 is placed in the drying tower filled with TMCS atmosphere for 10 minutes for hydrophobic treatment, so that an anti-adhesion layer is formed on the surface of the needle cover plate mold 9; Figure 3 As shown in 3d, the PDMS mixed solution is poured on the needle cover plate mold 9, and the PDMS curing agent mixed solution 10 is a 4:1 ratio of PDMS and curing agent. Then it is placed in a vacuum environment for 1 hour to allow the PDMS mixed solution to completely fill the needle cover plate mold 9 pattern; the needle cover plate mold 9 poured with the PDMS mixed solution is placed on a horizontal platform and left to stand for 10 minutes, and then baked in an oven at 60°C for 2 hours to cure the PDMS mixed solution; Figure 3 As shown in Figure 3e, the solidified PDMS is separated from the needle cover plate mold 9, and then the needle cover plate with connecting channels is obtained.

[0041] Step S2, such as Figure 4 As shown in Figure 4f, the unbonded biological vein spray needle and the spray needle cover are treated with oxygen plasma respectively, the treatment power of the oxygen plasma treatment is 20W, and the treatment time is 10s; and step S3 is entered; Step S3, such as Figure 4 As shown in Figure 4g, the unbonded biological venous spray needle and the spray needle cover plate after the treatment in step S2 are aligned and bonded, the unbonded biological venous spray needle is sealed, a biological venous spray needle micro-nano channel is formed, and a micro-nano spray needle is obtained. Embodiment 2

[0042] like Figure 1-Figure 4 As shown, in this embodiment, the organism used is an organism in the order Arachnids, and the biological bristle vein micro-nano structure is a leg with bristles in the order Arachnids.

[0043] Therefore, a method for manufacturing a micro-nano spray needle by a casting deposition self-sealing method comprises the following steps: Step S1, preparing an unbonded biological venous spray needle and a spray needle cover plate, and proceeding to step S2; like Figure 1 As shown, the method for preparing the unbonded biological venous spray needle comprises the following steps: Step S1.1, using a casting method to replicate the biological bristle vascular micro-nano structure to manufacture a biological vascular micro-nano spray needle substrate; The steps for obtaining the biological vascular micro-nano spray needle substrate include: Step S1.1.1, obtaining an organism having a biological bristle venation micro-nano structure, and purifying, drying, and hydrophobicizing the organism.

[0044] Among them, the purification, drying and hydrophobic treatment of organisms include: like Figure 1 As shown in 1a, the spider leg 1 is ultrasonically cleaned with deionized water for 25 minutes, the ultrasonic power is 90W, and the temperature is 27°C; the ultrasonic cleaning is repeated 3 times, and finally, a nitrogen air gun is used to blow dry and placed in a 50°C oven for 60 minutes to remove moisture, but it is not limited to this. In other embodiments, a hot plate can be used instead of an oven. 5 ml of trimethylchlorosilane (TMCS) is dripped into the drying tower, and after sealing and volatilizing for 10 minutes, the spider leg 1 is vertically placed in a sealed drying tower with a trimethylchlorosilane atmosphere for 20 minutes.

[0045] Step S1.1.2, as Figure 1 As shown in 1b, the purified and dried organism is laid flat on the PMMA substrate, and the PDMS curing agent mixed solution 10 is poured onto the organism of the PMMA substrate and cured to form a PDMS solidified body 2. The PDMS solidified body 2 is cut according to actual needs, and the PDMS solidified body 2 is separated from the spider leg 1 to obtain a biological venous micro-nano spray needle substrate. The PDMS curing agent mixed solution 10 is a PDMS and curing agent in a ratio of 8:1. Further, after collecting the spider leg 1, the leg bristles are messy before cleaning. After repeated ultrasonic cleaning, some fragile hairs have fallen off, and most of the remaining bristles are regular. After obtaining the PDMS solidified body 2, the nanochannel end is cut, and the port can obtain an array-distributed spray needle port. Furthermore, in order to improve the cutting stability, the present invention uses a relatively sharp coating knife in the prior art to avoid deformation of the channel caused by a blunt tool. Moreover, when cutting, cut from the back of the channel instead of the front, and cutting from the front of the channel is likely to cause channel deformation.

[0046] The steps of pouring the PDMS curing agent mixed solution 10 onto the organism of the PMMA substrate and curing include: the treated spider leg 1 is flatly fixed on the PMMA substrate, the PDMS curing agent mixed solution 10 is poured onto the spider leg 1, and then placed in a vacuum environment below 10Pa for 2 hours; and then placed on a horizontal stationary table and cured at room temperature for 28 hours. The PDMS curing agent mixed solution 10 is a PDMS and curing agent in a ratio of 8:1.

[0047] Among them, the step of separating the solidified PDMS from the organism includes: separating the solidified PDMS from the spider leg 1 to obtain the PDMS micro-nano mold 3; placing the PDMS micro-nano mold 3 in deionized water for ultrasonic cleaning for 2 hours to remove the bristles remaining on the PDMS micro-nano mold 3 during the demolding process. During the ultrasonic cleaning process, the structure should be kept facing down to make the bristles easier to detach from the PDMS micro-nano mold 3, wherein the ultrasonic power is 300W and the ultrasonic time is 60min; the PDMS micro-nano mold 3 after ultrasonic cleaning is blown dry with a nitrogen air gun and placed on a hot plate at 100°C for 30 minutes to remove moisture from the PDMS micro-nano mold 3 to obtain a biological vascular micro-nano spray needle substrate.

[0048] Step S1.2, such as Figure 2 As shown, a polymer deposition layer is deposited on the inner wall of the micro-nano channel of the biological venous micro-nano spray needle substrate by a polymer deposition method to form a biological venous spray needle nanochannel and obtain an unbonded biological venous spray needle. Figure 2 As shown in 2a, the polymer deposition method for growing the Parylene film 4 comprises the following steps: placing the biological venous micro-nano needle substrate into an oxygen plasma ashing apparatus for oxygen plasma treatment, with a treatment power of 30 W and a treatment time of 30 s; Figure 2 As shown in Figure 2b, the biological venous micro-nano-spray needle substrate after oxygen plasma treatment is placed in a Parylene deposition chamber with the structure facing upward; 0.15 g of Parylene is used for film growth, wherein the deposition pressure is 60 mTorr, and the nano-channel of the biological venous micro-nano-spray needle substrate is reduced by growing Parylene film 4, and Parylene film 4 is generated on the nano-channel surface of the biological venous micro-nano-spray needle substrate to obtain a spray needle nano-channel below 100 nm.

[0049] Specifically, the size of the end of the spider leg 1 is about 200nm, and 100nm and below is called a nanostructure. Above 100nm and below 1um is submicron. After obtaining the micro-nano channel, the submicron structure therein uses deposition technology to shrink the submicron pores, and finally forms a self-closed nanochannel. The size of the bristle end of the spider leg 1 is at the submicron level. Only thin film deposition technology is needed to shrink the submicron channel and form a self-closed channel, killing two birds with one stone. Therefore, there is no need for additional stretching and shrinking to obtain the nanochannel. After deposition, the nanochannel has been self-closed, and the channel has been transformed from a channel. However, the size of the micron channel is relatively too large and has not been self-closed; therefore, the micron channel is still a channel after being treated by the polymer deposition method. Further, after deposition, the micron channel and other planes (all exposed surfaces) will be deposited with a Parylene film 4; finally, the micron channel is shrunk, and the submicron channel therein forms a self-closed nanochannel.

[0050] like Figure 3 As shown, the preparation method of the spray needle cover plate includes the following steps: The spray needle cover plate is obtained by casting the spray needle cover plate mold 9.

[0051] Among them, Figure 3 As shown in 3a, the preparation method of the needle cover plate mold 9 includes the following steps: spin coating a layer of photoresist 6 on the silicon wafer 5, the photoresist 6 adopts AZ703 photoresist, but is not limited to this. In other embodiments, other types of positive photoresists in the prior art can be selected according to actual use requirements. The selection of photoresist 6 is not listed one by one here, as long as it can basically meet the requirements of photolithography, exposure, and development in this embodiment. Among them, the low-speed spin coating speed of the photoresist 6 is 900rpm, and the high-speed spin coating speed is 5000rpm; the silicon wafer 5 with the photoresist 6 is placed on a horizontal hot plate for pre-baking for 40 minutes, and the pre-baking temperature is 90°C. The treated heat-cured photoresist 6 is exposed and developed by a photolithography machine through a mask 7. Specifically, the silicon wafer 5 on which the photoresist 6 is spin-coated after pre-baking is placed under the photolithography machine, and the mask 7 is placed. The ultraviolet light 8 is transmitted through the mask 7 to expose the photoresist 6, wherein the exposure time is 70 seconds; after exposure, it is developed in a developer (AZ series developer) for 50 seconds, such as Figure 3 As shown in 3b, the exposed photoresist 6 is removed, and then placed in deionized water for 50 seconds to obtain a photoresist step with a width of 50 μm; it is dried with a nitrogen air gun, placed on a high-temperature hot plate at 200°C and baked for 30 minutes, and the photoresist step gradually changes from a rectangular step to a semicircular shape. Figure 3 As shown in FIG. 3c, the plate is then cooled to room temperature to obtain a spray needle cover plate mold 9.

[0052] The process of obtaining a needle cover plate by pouring a needle cover plate mold 9 includes the following steps: pouring a PDMS curing agent mixed solution 10 into the needle cover plate mold 9 and curing it; separating the cured PDMS solid body 2 from the PMMA substrate, and using the separated PDMS solid body 2 as the needle cover plate. Specifically, 5 ml of trimethylchlorosilane (TMCS) is dripped into a drying tower and sealed for 10 minutes; the needle cover plate mold 9 is placed in a drying tower filled with TMCS atmosphere for 20 minutes for hydrophobic treatment, so that an anti-adhesion layer is formed on the surface of the needle cover plate mold 9; Figure 3 As shown in 3d, the PDMS mixed solution is poured on the needle cover plate mold 9, and the PDMS curing agent mixed solution 10 is PDMS and curing agent in a ratio of 8:1. Then it is placed in a vacuum environment for 2 hours, so that the PDMS mixed solution can completely fill the needle cover plate mold 9 pattern; the needle cover plate mold 9 poured with the PDMS mixed solution is placed on a horizontal platform and left to stand for 20 minutes, and then baked in an oven at 80°C for 4 hours to cure the PDMS mixed solution; the cured PDMS is separated from the needle cover plate mold 9, and then a needle cover plate with a connecting channel is obtained. The PDMS curing agent mixed solution 10 is PDMS and curing agent in a ratio of 4:1 to 8:1.

[0053] Step S2, such as Figure 4 As shown in Figure 4f, the unbonded biological vein spray needle and the spray needle cover are treated with oxygen plasma respectively, the treatment power of the oxygen plasma treatment is 30W, and the treatment time is 30s; then proceed to step S3; Step S3, such as Figure 4 As shown in Figure 4g, the unbonded biological venous spray needle and the spray needle cover plate after the treatment in step S2 are aligned and bonded, the unbonded biological venous spray needle is sealed, a biological venous spray needle micro-nano channel is formed, and a micro-nano spray needle is obtained. Embodiment 3

[0054] like Figure 1-Figure 10 As shown, in this embodiment, the organism used is an organism in the order Arachnids, and the biological bristle vein micro-nano structure is a leg with bristles in the order Arachnids.

[0055] Therefore, a method for manufacturing a micro-nano spray needle by a casting deposition self-sealing method comprises the following steps: Step S1, preparing an unbonded biological venous spray needle and a spray needle cover plate, and proceeding to step S2; like Figure 1 As shown, the method for preparing the unbonded biological venous spray needle comprises the following steps: Step S1.1, using a casting method to replicate the biological bristle vascular micro-nano structure to manufacture a biological vascular micro-nano spray needle substrate; The steps for obtaining the biological vascular micro-nano spray needle substrate include: Step S1.1.1, obtaining an organism having a biological bristle venation micro-nano structure, and purifying, drying, and hydrophobicizing the organism.

[0056] Among them, the purification, drying and hydrophobic treatment of organisms include: like Figure 1 As shown in 1a, the spider leg 1 is ultrasonically cleaned with deionized water for 15 minutes, the ultrasonic power is 70W, and the temperature is 24°C; the ultrasonic cleaning is repeated 3 times, and finally, a nitrogen air gun is used to blow dry and placed in a 45°C oven for 45 minutes to remove moisture, but it is not limited to this. In other embodiments, a hot plate can be used instead of an oven. 3 ml of trimethylchlorosilane (TMCS) is dripped into the drying tower, and after sealing and volatilization for 7 minutes, the spider leg 1 is vertically placed in a sealed drying tower with a trimethylchlorosilane atmosphere for 15 minutes.

[0057] Step S1.1.2, as Figure 1 As shown in 1b, the purified and dried organism is laid flat on a PMMA substrate, and the PDMS curing agent mixed solution 10 is poured onto the organism on the PMMA substrate and cured to form a PDMS solidified body 2. The PDMS solidified body 2 is cut according to actual needs, and the PDMS of the PDMS solidified body 2 is separated from the spider leg 1 to obtain a biological venous micro-nano spray needle substrate. The PDMS curing agent mixed solution 10 is a 6:1 ratio of PDMS and curing agent. Further, after collecting the spider leg 1, the leg bristles are messy before cleaning. After repeated ultrasonic cleaning, some fragile hairs have fallen off, and most of the remaining bristles are regular. After obtaining the PDMS solidified body 2, the nanochannel end is cut, and the port can obtain an array-distributed spray needle port. Furthermore, in order to improve the cutting stability, the present invention uses a relatively sharp coating knife in the prior art to avoid deformation of the channel caused by a blunt tool. Moreover, when cutting, cut from the back of the channel instead of the front, and cutting from the front of the channel is likely to cause channel deformation.

[0058] Among them, the steps of pouring the PDMS curing agent mixed solution 10 onto the organism of the PMMA substrate and curing it include: the treated spider leg 1 is flatly fixed on the PMMA substrate, the PDMS curing agent mixed solution 10 is poured onto the spider leg 1, and then placed in a vacuum environment below 10Pa and evacuated for 1.2 hours; then placed on a horizontal stationary table and cured at room temperature for 24 hours.

[0059] Among them, the step of separating the solidified PDMS from the organism includes: separating the solidified PDMS from the spider leg 1 to obtain the PDMS micro-nano mold 3; placing the PDMS micro-nano mold 3 in deionized water for ultrasonic cleaning for 1.2 hours to remove the bristles remaining on the PDMS micro-nano mold 3 during the demolding process. During the ultrasonic cleaning process, the structure should be kept facing down to make the bristles easier to detach from the PDMS micro-nano mold 3, wherein the ultrasonic power is 200W and the ultrasonic time is 45 minutes; the PDMS micro-nano mold 3 after ultrasonic cleaning is blown dry with a nitrogen air gun and placed on a hot plate at 90°C for 20 minutes to remove moisture from the PDMS micro-nano mold 3 to obtain a biological vascular micro-nano spray needle substrate.

[0060] Step S1.2, such as Figure 2 As shown, a polymer deposition layer is deposited on the inner wall of the micro-nano channel of the biological venous micro-nano spray needle substrate by a polymer deposition method to form a biological venous spray needle nanochannel and obtain an unbonded biological venous spray needle. Figure 2 As shown in 2a, the polymer deposition method for growing the Parylene film 4 comprises the following steps: placing the biological venous micro-nano needle substrate into an oxygen plasma ashing apparatus for oxygen plasma treatment, with a treatment power of 25 W and a treatment time of 25 s; Figure 2 As shown in Figure 2b, the biological venous micro-nano-spray needle substrate after oxygen plasma treatment is placed in a Parylene deposition chamber with the structure facing upward; 0.1g of Parylene is used for film growth, wherein the deposition pressure is 45mTorr, and the growing Parylene film 4 is used to shrink the nanochannel of the biological venous micro-nano-spray needle substrate, and the Parylene film 4 is generated on the nanochannel surface of the biological venous micro-nano-spray needle substrate to obtain a spray needle nanochannel below 100nm.

[0061] Specifically, the size of the end of the spider leg 1 is about 200nm, and 100nm and below is called a nanostructure. Above 100nm and below 1um is submicron. After obtaining the micro-nano channel, the submicron structure therein uses deposition technology to shrink the submicron pores, and finally forms a self-closed nanochannel. The size of the bristle end of the spider leg 1 is at the submicron level. Only thin film deposition technology is needed to shrink the submicron channel and form a self-closed channel, killing two birds with one stone. Therefore, there is no need for additional stretching and shrinking to obtain the nanochannel. After deposition, the nanochannel has been self-closed, and the channel has been transformed from a channel. However, the size of the micron channel is relatively too large and has not been self-closed; therefore, the micron channel is still a channel after being treated by the polymer deposition method. Further, after deposition, the micron channel and other planes (all exposed surfaces) will be deposited with a Parylene film 4; finally, the micron channel is shrunk, and the submicron channel therein forms a self-closed nanochannel.

[0062] like Figure 3As shown, the preparation method of the spray needle cover plate includes the following steps: The spray needle cover plate is obtained by casting the spray needle cover plate mold 9.

[0063] Among them, Figure 3 As shown in 3a, the preparation method of the needle cover plate mold 9 includes the following steps: spin coating a layer of photoresist 6 on the silicon wafer 5, the photoresist 6 is AZ703 photoresist, but not limited to this. In other embodiments, other types of positive photoresists and corresponding developers in the prior art can be selected according to actual use requirements. The selection of photoresist 6 is not listed one by one here, as long as it can basically meet the requirements of photolithography, exposure, and development of photoresist 6 in this embodiment. Among them, the low-speed spin coating speed of photoresist 6 is 750rpm, and the high-speed spin coating speed is 3500rpm; the silicon wafer 5 with the photoresist 6 is placed on a horizontal hot plate for pre-baking for 35min, and the pre-baking temperature is 85℃. The treated heat-cured photoresist 6 is exposed and developed by a photolithography machine through a mask 7. Specifically, the silicon wafer 5 on which the photoresist 6 is spin-coated after pre-baking is placed under the photolithography machine, and the mask 7 is placed. The ultraviolet light 8 is transmitted through the mask 7 to expose the photoresist 6, wherein the exposure time is 50 seconds; after exposure, it is developed in a developer (AZ series developer) for 40 seconds, such as Figure 3 As shown in Figure 3b, the exposed photoresist 6 is removed and then placed in deionized water for 40 seconds to obtain a photoresist step with a width of 50 μm. It is dried with a nitrogen air gun and placed on a high-temperature hot plate at 175°C for 25 minutes. The photoresist step gradually changes from a rectangular step to a semicircular shape. Figure 3 As shown in FIG. 3c, the plate is then cooled to room temperature to obtain a spray needle cover plate mold 9.

[0064] The process of obtaining a needle cover plate by pouring the needle cover plate mold 9 includes the following steps: pouring the PDMS curing agent mixed solution 10 into the needle cover plate mold 9 and curing it; separating the cured PDMS solid body 2 from the PMMA substrate, and using the separated PDMS solid body 2 as the needle cover plate. Specifically, 3 ml of trimethylchlorosilane (TMCS) is dripped into the drying tower and sealed for 7.5 minutes; the needle cover plate mold 9 is placed in a drying tower filled with TMCS atmosphere for 15 minutes for hydrophobic treatment, so that an anti-adhesion layer is formed on the surface of the needle cover plate mold 9; the PDMS mixed solution is poured on the needle cover plate mold 9, and the PDMS curing agent mixed solution 10 is a 6:1 ratio of PDMS and curing agent. Then place it in a vacuum environment for 1.5 hours to allow the PDMS mixed solution to completely fill the needle cover plate mold 9; place the needle cover plate mold 9 poured with the PDMS mixed solution on a horizontal platform and let it stand for 15 minutes, and then bake it in an oven at 70°C for 3 hours to solidify the PDMS mixed solution; separate the solidified PDMS from the needle cover plate mold 9, and then obtain a needle cover plate with a connecting channel.

[0065] Step S2, such as Figure 4 As shown in Figure 4f, the unbonded biological vein spray needle and the spray needle cover are treated with oxygen plasma respectively, the treatment power of the oxygen plasma treatment is 25W, and the treatment time is 20s; then proceed to step S3; Step S3, such as Figure 4 As shown in Figure 4g, the unbonded biological venous spray needle and the spray needle cover plate after the treatment in step S2 are aligned and bonded, the unbonded biological venous spray needle is sealed, a biological venous spray needle micro-nano channel is formed, and a micro-nano spray needle is obtained. Embodiment 4

[0066] Based on Example 3, the PDMS curing temperature is 80° C. and the curing time is 2 h. Embodiment 5

[0067] Based on Example 3, the PDMS curing temperature is 75° C. and the curing time is 2.5 h. Embodiment 6

[0068] Based on Example 3, the PDMS curing temperature is 65° C. and the curing time is 3.5 h. Embodiment 7

[0069] Based on Example 3, the PDMS curing temperature is 60° C. and the curing time is 4 h. Embodiment 8

[0070] Based on the third embodiment, Figure 5As shown, in step S3, a steel needle 11 with a diameter of 60 μm after hydrophilic treatment is inserted into a short channel with a diameter of 50 μm between the bonded biological venous spray needle and the spray needle cover plate for interference fit to obtain a micro-nano spray needle. Embodiment 9

[0071] The spray needle was prepared by the method of manufacturing micro-nano spray needle by the casting deposition self-sealing method of Example 8. Embodiment 10

[0072] Based on the third embodiment, the photoresist 6 uses SU-8 photoresist and the developer uses SU-8 developer. However, this is not limited to this. In other embodiments, other types of negative photoresists and corresponding developers in the prior art can be selected according to actual use requirements. The selection of photoresists 6 will not be listed one by one here, as long as they can basically meet the requirements of photolithography, exposure, and development of photoresists 6 in this embodiment. Further, when using negative photoresists, the black and white parts of the mask 7 are Figure 3 3a is the opposite; that is, if the positive photoresist and the negative photoresist want to obtain the same pattern, the black and white parts of the mask 7 (ie, the light-transmitting and light-shielding areas) can be opposite.

[0073] Working principle: The invention discloses a method for manufacturing a micro-nano spray needle by a casting deposition self-sealing method and a spray needle, wherein a micro-nano cross-scale spray needle nanochannel is obtained by replicating the micro-nano structure of biological bristle veins by a casting method; a spray needle nanochannel is obtained by a polymer deposition method; and finally, an oxygen plasma-assisted bonding method is used to seal the biological vein spray needle micro-nano channel to obtain a complete micro-nano spray needle.

[0074] The bristle structure of spider legs 1 was replicated by casting to obtain a submicron pattern, and the submicron pattern was reduced to a nano pattern below 100nm by polymer deposition, thereby obtaining a nozzle nanochannel; the nozzle cover was manufactured by high-temperature post-baking, and finally the biological vein nozzle micro-nano channel was sealed by oxygen plasma-assisted bonding to obtain a polymer micro-nano cross-scale nozzle. The production of micro-nano nozzles using the technology of the present invention simplifies the manufacturing process, reduces production costs, and achieves the dual advantages of process simplicity and economic benefits.

[0075] The above specific implementation methods are specific support for the scheme ideas proposed in the present invention, and cannot be used to limit the protection scope of the present invention. Any equivalent changes or equivalent modifications made on the basis of this technical scheme in accordance with the technical ideas proposed in the present invention still fall within the scope of protection of the technical scheme of the present invention.

Claims

1. A method for manufacturing micro-nano spray needles by a casting deposition self-sealing method, characterized in that: The following steps are involved: Step S1, preparing an unbonded biological venous spray needle and a spray needle cover plate, and proceeding to step S2; The method for preparing the unbonded biological venous spray needle comprises the following steps: Step S1.1, using a casting method to replicate the biological bristle vascular micro-nano structure to manufacture a biological vascular micro-nano spray needle substrate: Step S1.2, using a polymer deposition method to deposit a polymer deposition layer on the inner wall of the micro-nano channel of the biological venous micro-nano spray needle substrate to form a biological venous spray needle nanochannel to obtain an unbonded biological venous spray needle; The preparation method of the spray needle cover plate comprises the following steps: The nozzle cover plate is obtained by pouring the nozzle cover plate mold; Step S2, respectively subjecting the unbonded biological venous spray needle and the spray needle cover plate to oxygen plasma treatment, and then proceeding to step S3; Step S3, aligning and bonding the unbonded biological venous spray needle and the spray needle cover plate processed in step S2, sealing the unbonded biological venous spray needle, forming a biological venous spray needle micro-nano channel, and obtaining a micro-nano spray needle.

2. The method for manufacturing micro-nano spray needles by a casting deposition self-sealing method according to claim 1, characterized in that: The steps of obtaining the biological ventricle micro-nano spray needle substrate include: Step S1.1.1, obtaining an organism having a biological bristle vein micro-nano structure, and purifying, drying, and hydrophobicizing the organism; Step S1.1.2, spreading the purified and dried organism on a PMMA substrate, pouring a PDMS curing agent mixed solution onto the organism on the PMMA substrate and curing it, separating the cured PDMS from the organism, and obtaining a biological vascular micro-nano spray needle substrate.

3. The method for manufacturing micro-nano spray needles by a casting deposition self-enclosed method according to claim 2, characterized in that: The preparation method of the spray needle cover plate mold comprises the following steps: exposing and developing the treated thermal curing photoresist through a mask plate using a photolithography machine to obtain the spray needle cover plate mold; The nozzle cover plate is obtained by pouring the nozzle cover plate mold, which includes the following steps: pouring a PDMS curing agent mixed solution into the nozzle cover plate mold and curing it, separating the cured PDMS solid body from the PMMA substrate, and using the separated PDMS solid body as the nozzle cover plate.

4. The method for manufacturing micro-nano spray needles by a casting deposition self-enclosed method according to claim 3, characterized in that: The organism is an organism in the order Diptera of the order Arachnid or Insecta, and the biological bristle vein micro-nano structure is the leg bristles of the organism in the order Diptera of the order Arachnid or Insecta.

5. The method for manufacturing micro-nano spray needles by a casting deposition self-sealing method according to claim 4, characterized in that: Purifying, drying and hydrophobic treatment of the organisms include: The organisms were ultrasonically cleaned with deionized water for 5-25 min, with an ultrasonic power of 50-90 W and a temperature of 21-27 °C; Repeat ultrasonic cleaning for 3 times, and finally use a nitrogen air gun to blow dry and place on a 40-50℃ hot plate or oven for 30-60 min to remove moisture; Drop 1-5 ml of trimethylsilyl chloride into the drying tower, seal it for 5-10 minutes, then place the organism into the drying tower filled with trimethylsilyl chloride and perform hydrophobic treatment for 10-20 minutes; And / or, the step of pouring the PDMS curing agent mixed solution onto the organism on the PMMA substrate and curing the mixture comprises: The treated organism is fixed flat on a PMMA substrate, and the PDMS curing agent mixed solution is poured onto the organism, which is then placed in a vacuum environment below 10Pa for 0.5 to 2 hours; then placed on a horizontal stationary table and cured at room temperature for 20 to 28 hours; The steps to separate the cured PDMS from the organism include: The solidified PDMS is separated from the organism to obtain a PDMS micro-nano mold; the PDMS micro-nano mold is placed in deionized water for ultrasonic cleaning for 0.5 to 2 hours to remove the bristles remaining on the PDMS micro-nano mold during the demolding process. During the ultrasonic cleaning process, the structure should be kept facing downward to make it easier for the bristles to detach from the PDMS micro-nano mold. The ultrasonic power is 100W to 300W, the ultrasonic time is 30 to 60 minutes, and the ultrasonic treatment is repeated 3 times; the PDMS micro-nano mold after ultrasonic cleaning is blown dry with a nitrogen air gun and placed on a hot plate at 80 to 100°C for 10 to 30 minutes to remove moisture from the PDMS micro-nano mold to obtain a biological vascular micro-nano spray needle substrate.

6. The method for manufacturing micro-nano spray needles by a casting deposition self-sealing method according to claim 5, characterized in that: The polymer deposition method comprises the following steps: The biological ventricle micro-nano spray needle substrate is placed in an oxygen plasma ashing instrument for oxygen plasma treatment, with a treatment power of 20-30 W and a treatment time of 15-30 s; the biological ventricle micro-nano spray needle substrate after oxygen plasma treatment is placed in a Parylene deposition chamber with the structure facing upward; 0.05-0.15 g of Parylene is used for thin film growth, wherein the deposition pressure is 20-60 mTorr, and the Parylene film growth method is used to shrink the micro-nano channel of the biological ventricle micro-nano spray needle substrate, and a Parylene film is generated on the surface of the micro-nano channel of the biological ventricle micro-nano spray needle substrate, which is self-sealed to obtain a spray needle nanochannel below 100 nm.

7. The method for manufacturing micro-nano spray needles by a casting deposition self-enclosed method according to claim 6, characterized in that: The steps of obtaining the nozzle cover plate by pouring the nozzle cover plate mold include: Spin-coat a layer of photoresist on the silicon wafer, wherein the low-speed spin-coating speed is 600~900rpm and the high-speed spin-coating speed is 1500~5000rpm; Place the silicon wafer with the photoresist spin-coated on a horizontal hot plate and pre-bake for 30-40 minutes at a temperature of 80-90°C. The silicon wafer with the photoresist spun on it after pre-baking is placed under the photolithography machine, and the mask is placed. The photoresist is exposed to ultraviolet light through the mask, and the exposure time is 30-70s. After exposure, develop in AZ series developer for 30-50 seconds to remove the exposed photoresist, and then rinse in deionized water for 30-50 seconds to obtain a photoresist step with a width of 50 μm; Blow dry with a nitrogen air gun, place on a high-temperature hot plate at 150-200°C and bake for 20-30 minutes, the photoresist step gradually changes from a rectangular step to a semicircular shape; then cool to room temperature with the plate to obtain a needle cover plate mold; 1-5 ml of trimethylchlorosilane is dripped into the drying tower and sealed for 5-10 minutes; the spray needle cover plate mold is placed in the drying tower filled with trimethylchlorosilane atmosphere for 10-20 minutes for hydrophobic treatment, so that an anti-adhesion layer is formed on the surface of the spray needle cover plate mold; Pour a PDMS mixed solution with a ratio of 4:1 to 8:1 onto the needle cover plate mold, and then place it in a vacuum environment for 1 to 2 hours to allow the PDMS mixed solution to completely fill the needle cover plate mold pattern; Place the needle cover plate mold poured with the PDMS mixed solution on a horizontal platform and let it stand for 10-20 minutes, then bake it in an oven at 60-80°C for 2-4 hours to solidify the PDMS mixed solution; The solidified PDMS is separated from the needle cover plate mold, and the needle cover plate with connecting channels is then obtained.

8. The method for manufacturing micro-nano spray needles by a casting deposition self-sealing method according to claim 7, characterized in that: In step 3, the unbonded biological venous spray needle and the spray needle cover plate processed in step 2 are aligned and bonded, the unbonded biological venous spray needle is sealed, a biological venous spray needle micro-nano channel is formed, and a micro-nano spray needle is obtained: Before bonding, the biological vein spray needle and the spray needle cover plate were treated with oxygen plasma at a treatment power of 20-30W and a treatment time of 10-30s; A hydrophilic treated steel needle with a diameter of 60 μm is inserted into a short channel with a diameter of 50 μm between the bonded biological venous spray needle and the spray needle cover plate for interference fit to obtain a micro-nano spray needle.

9. The method for manufacturing micro-nano spray needles by a casting deposition self-enclosed method according to claim 8, characterized in that: The hydrophobic treatment of the organism comprises: dripping 1-5 ml of trimethylchlorosilane into a sealed drying tower, volatilizing for 5-10 minutes, and vertically placing the spider leg into a sealed drying tower with trimethylchlorosilane atmosphere for 10-20 minutes; And / or, the photoresist is a positive photoresist, and the developer is a positive photoresist developer; or, the photoresist is a negative photoresist, and the developer is a negative photoresist developer; and / or, the PDMS curing temperature is 80°C to 60°C, and the curing time is 2h to 4h; And / or, the ratio of PDMS to curing agent in the PDMS-curing agent mixed solution is 4:1 to 8:

1.

10. A micro-nano spray needle manufactured by a casting deposition self-sealing method, characterized in that: The spray needle is prepared by the method for manufacturing micro-nano spray needles by the casting deposition self-sealing method described in any one of claims 1 to 9.

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