Recyclable photocuring 3D printed soluble microneedle patch and preparation method thereof

Abstract

The invention discloses a recyclable photocuring 3D printed soluble microneedle patch and a preparation method thereof. The microneedle patch is composed of a soluble needle body layer and a flexible recoverable backing layer. The needle body layer is prepared into a polymerizable eutectic solvent through a specific composition, eutectic gel of a multi-hydrogen-bond cross-linked network is formed during photopolymerization, and rapid dissolution and effective drug delivery can be achieved. Eutectic gel prepared from the backing layer by utilizing a similar principle can be dissolved and recycled through ethanol and is circularly printed. The DLP 3D printing technology is utilized, personalized manufacturing of the soluble microneedle patch is achieved, meanwhile, the problem that a traditional microneedle backing layer cannot be recycled is solved, resource waste and environmental pollution are reduced, and the soluble microneedle patch is suitable for multiple fields such as drug delivery, vaccination and skincare.

Description

Technical Field

[0001] The present invention belongs to the technical field of biomedical materials, and in particular relates to a soluble microneedle patch prepared by adopting a cyclic light-curing 3D printing technology. Background Art

[0002] As an emerging transdermal drug delivery technology, microneedle patches have broad application prospects. Usually, microneedle patches are composed of a backing layer and a needle body layer. With the help of tiny needles, they penetrate the stratum corneum of the skin and accurately deliver drugs to the subcutaneous tissue, thereby achieving painless and efficient drug delivery. Microneedles mainly include solid microneedles, hollow microneedles, coated microneedles, swellable microneedles and soluble microneedles. Among them, soluble microneedles account for about 35%, which is the most widely used and most important one. Its application fields are diverse, including but not limited to drug treatment, vaccination, beauty and skin care, etc.

[0003] At present, soluble microneedles are mainly prepared by the template method, but this method has many shortcomings, such as high cost, low production efficiency, and difficulty in preparing complex structures. For example, the patent "A method for accelerating the molding and rapid dissolution of polyvinyl alcohol soluble microneedles and prepared microneedles" with publication number CN110947085A uses the template method to manufacture microneedles. Although this method is simple and fast, it still cannot get rid of the limitation that the template method cannot achieve personalized manufacturing. In comparison, 3D printing technology has unique advantages. It can quickly and accurately create microneedles with complex structures and can achieve personalized customization. 3D printing technology mainly includes extrusion molding, photocuring molding, etc. Patent CN115139514B proposes a method for preparing a 3D printed degradable and easily separable microneedle array, and uses fused deposition modeling 3D printing technology to prepare polylactic acid-based soluble microneedles. However, the microneedles prepared by these extrusion-based 3D printing technologies have poor precision and face problems such as overspraying, nozzle clogging, and dirt during the printing process, which is not conducive to the large-scale production of soluble microneedles.

[0004] Compared with 3D printing technology based on extrusion molding, photocuring 3D printing technology has the characteristics of high precision and high resolution, and is suitable for manufacturing microneedles with fine structures. As a type of photocuring 3D printing technology, DLP 3D printing technology can quickly cure photosensitive materials through digital light processing technology to achieve efficient 3D printing. At present, in the field of microneedle preparation, photocuring 3D printing technology has been used to prepare swelling microneedles. In the published patent CN115957430A, a polymerizable eutectic solvent is used as a 3D printing ink, and its high drug loading and rapid photocuring performance are applied to prepare a eutectic gel microneedle patch that can release drugs intelligently in one step. However, these microneedle patches are all swelling microneedle patches, and their polymer networks are covalently cross-linked, which causes the needle body layer to swell and release drugs after piercing the skin, and cannot achieve dissolution and release of drugs.

[0005] In addition, after the existing microneedle patches are used, the residual backing layer is often discarded. Most of the photocurable 3D printing resins are derived from non-renewable fossil energy sources, and the discarded 3D printed parts are difficult to recycle, which can easily cause serious waste of resources and environmental pollution. With the continuous improvement of the country's environmental protection requirements, it has become a top priority to vigorously promote the development of recyclable materials. Some researchers have introduced dynamic covalent bonds into photocurable 3D printing resins. For example, in patent CN116478325A, acrylate monomers are mixed with RAFT agents, dynamic crosslinkers and photoinitiators to form a recyclable 3D printing photosensitive resin solution. After DLP 3D printing and curing, high-precision parts with recyclability are obtained. However, these works are more about demonstrating the feasibility of recyclable photocurable 3D printing technology, and their specific materials are not suitable for preparing microneedle backing layers. In view of the above situation, it is particularly important to develop a soluble microneedle patch prepared by recyclable photocurable 3D printing technology. This patch can not only achieve the dissolution of the needle body layer, but also ensure the recyclability of the backing layer, thereby reducing resource waste and environmental pollution. Summary of the invention

[0006] In order to solve the deficiencies existing in the above-mentioned background technology, mainly the technical problems that the current photocuring 3D printing technology is mainly used to prepare swellable microneedles, cannot dissolve the drug, and the backing layer cannot be recycled, a recyclable DLP 3D printed soluble microneedle patch and a preparation method thereof are provided to overcome the deficiencies of the soluble microneedle preparation method in the prior art, realize the precise and personalized manufacturing of microneedle patches, ensure that the needle body layer can dissolve the drug, and at the same time make the backing layer which accounts for most of the microneedle material recyclable, thereby reducing resource waste and environmental pollution.

[0007] The technical solution of the present invention is:

[0008] A soluble microneedle patch capable of cyclic photocuring 3D printing, the soluble microneedle patch comprising a needle body layer and a backing layer;

[0009] The raw materials for preparing the needle layer include hydrogen bond acceptors, hydrogen bond donors A, photoinitiators and effective ingredients;

[0010] The hydrogen bond acceptor is at least one of choline chloride (ChCl) and N-vinyl pyrrolidone (NVP);

[0011] The hydrogen bond donor A is at least one of itaconic acid (IA), maleic acid (MA), and N-isopropylacrylamide (NIPAM);

[0012] The photoinitiator is at least one of 2,4,6-trimethylbenzoyl diphenylphosphine oxide (TPO) and 2,4,6-trimethylbenzoyl ethylphosphinate (TPO-L);

[0013] The active ingredient is at least one of a protein, a polypeptide, a gene, an antibody, an anesthetic, a vaccine, a chemically synthesized drug, a natural drug molecule, a cosmetic ingredient, and a nanoscale drug carrier;

[0014] The molar ratio of the hydrogen bond acceptor to the hydrogen bond donor A is 1:0.05-10;

[0015] Taking the total mass of the raw materials for preparing the needle body layer as 100%, the mass of the photoinitiator is 0.01% to 5%, and the mass of the active ingredient is greater than 0 and less than 40%;

[0016] The raw materials for preparing the backing layer include a hydrogen bond acceptor, a hydrogen bond donor B and a photoinitiator;

[0017] The hydrogen bond donor B is at least one of itaconic acid, maleic acid, hydroxyethyl methacrylate (HEMA), N-isopropylacrylamide (NIPAM), glycerol (Gly), 3-acrylamidophenylboronic acid (AAPBA), and acrylic acid (AA);

[0018] The molar ratio of the hydrogen bond acceptor to the hydrogen bond donor B is 1:0.05-10;

[0019] Taking the total mass of the raw materials for preparing the backing layer as 100%, the mass of the photoinitiator is 0.01% to 5%.

[0020] A method for preparing a soluble microneedle patch capable of cyclic light-curing 3D printing, the method comprising the steps of:

[0021] (1) Preparation of backing layer 3D printing ink: hydrogen bond acceptor and hydrogen bond donor B in the raw materials for preparing the backing layer are mixed and heated to prepare polymerizable eutectic solvent B, and then the photoinitiator in the raw materials for preparing the backing layer is added and mixed to prepare the backing layer 3D printing ink;

[0022] (2) Configuration of needle layer 3D printing ink: hydrogen bond acceptor and hydrogen bond donor A in the raw materials for preparing the needle layer are mixed and heated to form a polymerizable eutectic solvent A, and then the photoinitiator and active ingredient in the raw materials for preparing the needle layer are added and mixed to prepare the needle layer 3D printing ink;

[0023] (3) performing photocuring 3D printing using the backing layer 3D printing ink obtained in step (1) to obtain a backing layer;

[0024] (4) Using the needle body layer 3D printing ink obtained in step (2) to perform photocuring 3D printing of the needle body layer on the backing layer to obtain a soluble microneedle patch.

[0025] An application of a soluble microneedle patch that can be 3D printed by recyclable light curing, the method comprising the steps of: placing the soluble microneedle patch tightly on the skin and allowing the needle body layer to penetrate the skin, waiting for a set time for the needle body layer to dissolve in the skin, and finally removing the backing layer from the skin to complete the application of the soluble microneedle patch, the set time being 10-60 minutes.

[0026] The method for recovering the removed backing layer is as follows: the backing layer removed from the skin is dissolved in ethanol at 50-70°C to obtain a recovery solution, and the recovery solution is then dried to obtain a precipitate, wherein the precipitate includes hydrogen bond acceptors and hydrogen bond donors B used as raw materials for preparing the backing layer, that is, the obtained precipitate can be used as a raw material for configuring the backing layer 3D printing ink in step (1).

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The present invention provides a recyclable photocurable 3D printed soluble microneedle patch and a preparation method thereof. The soluble microneedle patch structure is mainly divided into a soluble needle body layer and a flexible and recyclable backing layer. The soluble needle body layer utilizes the strong hydrogen bonding inside the polymerizable eutectic solvent to provide hydrogen bonding cross-linking sites during photopolymerization, thereby forming a eutectic gel with a multiple hydrogen bonding cross-linking network. This eutectic gel cross-linked by multiple hydrogen bonding will be destroyed by the action of water, and the cross-linking sites will disappear, thereby becoming a linear polymer with good water solubility. Therefore, it has a rapid dissolution effect. The flexible and recyclable backing layer also utilizes the strong hydrogen bonding inside the polymerizable eutectic solvent to provide hydrogen bonding cross-linking sites during photopolymerization, forming a eutectic gel with a multiple hydrogen bonding cross-linking network. Unlike the eutectic gel of the needle body layer, the hydrogen bonding cross-linking of the eutectic gel of the backing layer is more easily destroyed by heated ethanol to form a linear polymer, thereby dissolving in ethanol. The recovered precipitate contains hydrogen bond acceptors and hydrogen bond donors of linear polymers and non-polymer monomers, so adding polymerizable eutectic solvents and initiators again can realize the cyclic 3D printing process again. The mechanical properties of the material are controllable. The preparation of soluble microneedle patches that are recyclable, adjustable, and DLP 3D printable is achieved.

[0029] The present invention discloses a soluble microneedle patch capable of recyclable photocurable 3D printing and a preparation method thereof. The microneedle patch is composed of a soluble needle body layer and a flexible recyclable backing layer. The needle body layer is a polymerizable eutectic solvent made of a specific composition, and forms a eutectic gel with a multiple hydrogen bond cross-linked network during photopolymerization, which can achieve rapid dissolution and effective drug delivery. The backing layer is a eutectic gel prepared using a similar principle, which can be dissolved, recovered and printed cyclically by ethanol. The present invention utilizes DLP 3D printing technology to achieve personalized manufacturing of soluble microneedle patches, while solving the problem that the traditional microneedle backing layer is non-recyclable, reducing resource waste and environmental pollution, and is suitable for multiple fields such as drug delivery, vaccination, and beauty and skin care. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Schematic diagram of the structure of soluble microneedle patches of different shapes;

[0031] Figure 2 This is a schematic diagram of the dissolution process of the soluble microneedles in Example 1 after being inserted into the mouse skin;

[0032] Figure 3 Schematic diagram of the process of recyclable 3D printing soluble microneedles. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical scheme and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but are not intended to limit the present invention. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0034] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0035] Example 1

[0036] ChCl, AAPBA, and Gly were mixed in a molar ratio of 1:5:2, and then heated in a water bath at 70°C to dissolve to prepare a polymerizable eutectic solvent B. Then, a photoinitiator TPO-L was added at a mass ratio of 2% to obtain a backing layer 3D printing photosensitive ink.

[0037] NVP, NIPAM, and MA were mixed in a molar ratio of 4:2:1, and then heated in a water bath at 65°C to dissolve to prepare a polymerizable eutectic solvent A. Then, 0.2% by mass of the photoinitiator TPO and 0.01% by mass of the active ingredient insulin were added to obtain the needle layer 3D printing photosensitive ink.

[0038] Subsequently, the backing layer 3D printing photosensitive ink is added into the 3D printer and then light-cured printing is performed to print the backing layer, and then the needle body layer 3D printing photosensitive ink is added into the 3D printer and light-cured printing is performed on the backing layer to print the needle body layer, thereby obtaining a soluble microneedle patch;

[0039] 3D printing parameters: exposure time 10s, bottom layer exposure time 60s, layer thickness 0.05mm.

[0040] To demonstrate the personalized manufacturing of 3D printing, different shapes of soluble microneedle patches were designed. Figure 1 As shown, conical, triangular pyramidal, pyramidal and pentagonal star-shaped soluble microneedle patches were successfully prepared.

[0041] The prepared soluble microneedles were inserted into the skin of mice and taken out every 5 minutes to observe the dissolution effect. Figure 2 As shown, after a 10-minute puncture period, the needle height was reduced by approximately 80%, and finally completely dissolved within 15 minutes, and finally the backing layer was removed from the skin;

[0042] The removed backing layer was dissolved and recovered in 60°C ethanol, and the ethanol was dried to obtain a precipitate. The precipitate was added to the new backing layer 3D printing photosensitive ink at a mass fraction of 10% to fully dissolve, and the recovered backing layer 3D printing photosensitive ink was obtained. The backing layer was obtained by 3D printing again, and the microneedle body layer was continued to be printed to obtain a soluble microneedle patch, such as Figure 3 shown.

[0043] Example 2

[0044] NVP, AA, and MA were mixed in a molar ratio of 1:2:1, and then heated in a 50°C water bath to dissolve to prepare a polymerizable eutectic solvent B. Then, 0.1% by mass of a photoinitiator TPO-L was added to obtain a backing layer 3D printing photosensitive ink.

[0045] ChCl, IA, and NVP were mixed in a molar ratio of 1:2:7, and then heated in a water bath at 70°C to dissolve to prepare a polymerizable eutectic solvent A. Then, 0.2% by mass of the photoinitiator TPO and 0.03% by mass of the active ingredient lidocaine were added to obtain the needle layer 3D printing photosensitive ink.

[0046] Subsequently, the backing layer 3D printing photosensitive ink is added into the 3D printer and then light-cured printing is performed to print the backing layer, and then the needle body layer 3D printing photosensitive ink is added into the 3D printer and light-cured printing is performed on the backing layer to print the needle body layer, thereby obtaining a soluble microneedle patch;

[0047] 3D printing parameters: exposure time 2s, bottom layer exposure time 60s, layer thickness 0.05mm.

[0048] The prepared soluble microneedles were inserted into the mouse skin. After a puncture period of 15 minutes, the microneedle body layer was completely dissolved, and finally the backing layer was removed from the skin.

[0049] The removed backing layer was dissolved and recovered in 65°C ethanol, and the ethanol was dried to obtain a precipitate, which was then added to a new backing layer 3D printing photosensitive ink at a mass fraction of 8% to fully dissolve, thereby obtaining a recovered backing layer 3D printing photosensitive ink. The backing layer was 3D printed again, and the microneedle body layer was continued to be printed to obtain a soluble microneedle patch.

[0050] Example 3

[0051] ChCl, NIPAM, and Gly were mixed in a molar ratio of 1:4:1, and then heated in a water bath at 60°C to dissolve to prepare a polymerizable eutectic solvent B. Then, a photoinitiator TPO-L was added at a mass ratio of 1% to obtain a backing layer 3D printing photosensitive ink.

[0052] NVP and MA were mixed at a molar ratio of 5:1, and then heated in a water bath at 60°C to dissolve to prepare a polymerizable eutectic solvent A. Then, 0.3% by mass of the photoinitiator TPO and 0.2% by mass of the active ingredient mangiferin were added to obtain the needle layer 3D printing photosensitive ink.

[0053] Subsequently, the backing layer 3D printing photosensitive ink is added into the 3D printer and then light-cured printing is performed to print the backing layer, and then the needle body layer 3D printing photosensitive ink is added into the 3D printer and light-cured printing is performed on the backing layer to print the needle body layer, thereby obtaining a soluble microneedle patch;

[0054] 3D printing parameters: exposure time 5s, bottom layer exposure time 40s, layer thickness 0.1mm.

[0055] The prepared soluble microneedles were inserted into the mouse skin. After a puncture period of 30 minutes, the microneedle body layer was completely dissolved, and finally the backing layer was removed from the skin.

[0056] The removed backing layer was dissolved and recovered in 70°C ethanol, and the ethanol was dried to obtain a precipitate, which was then added to a new backing layer 3D printing photosensitive ink at a mass fraction of 12% to fully dissolve, thereby obtaining a recovered backing layer 3D printing photosensitive ink. The backing layer was 3D printed again, and the microneedle body layer was continued to be printed to obtain a soluble microneedle patch.

[0057] Example 4

[0058] ChCl, AA, and AAPBA were mixed in a molar ratio of 1:3:2, and then heated in a water bath at 80°C to dissolve to prepare a polymerizable eutectic solvent B. Then, a photoinitiator TPO was added at a mass ratio of 0.2% to obtain a backing layer 3D printing photosensitive ink.

[0059] ChCl, NVP, and NIPAM were mixed in a molar ratio of 1:1:4, and then heated in a water bath at 70°C to dissolve to prepare a polymerizable eutectic solvent A. Then, 0.3% by mass of the photoinitiator TPO and 1% by mass of the active ingredient salicylic acid were added to obtain the needle layer 3D printing photosensitive ink.

[0060] Subsequently, the backing layer 3D printing photosensitive ink is added into the 3D printer and then light-cured printing is performed to print the backing layer, and then the needle body layer 3D printing photosensitive ink is added into the 3D printer and light-cured printing is performed on the backing layer to print the needle body layer, thereby obtaining a soluble microneedle patch;

[0061] 3D printing parameters: exposure time 20s, bottom layer exposure time 60s, layer thickness 0.05mm.

[0062] The prepared soluble microneedles were inserted into the mouse skin. After a puncture period of 20 minutes, the microneedle body layer was completely dissolved, and finally the backing layer was removed from the skin.

[0063] The removed backing layer was dissolved and recovered in 50°C ethanol, and the ethanol was dried to obtain a precipitate, which was then added to a new backing layer 3D printing photosensitive ink at a mass fraction of 20% to fully dissolve, thereby obtaining a recovered backing layer 3D printing photosensitive ink. The backing layer was 3D printed again, and the microneedle body layer was continued to be printed to obtain a soluble microneedle patch.

[0064] Example 5

[0065] ChCl, AA, and Gly were mixed in a molar ratio of 1:4:1, and then heated in a water bath at 80°C to dissolve to prepare a polymerizable eutectic solvent B. Then, a photoinitiator TPO was added at a mass ratio of 0.2% to obtain a backing layer 3D printing photosensitive ink.

[0066] NVP and NIPAM were mixed in a molar ratio of 1:1, and then heated in a water bath at 60°C to dissolve to prepare a polymerizable eutectic solvent A. Then, 0.5% by mass of the photoinitiator TPO-L and 2% by mass of the active ingredient lidocaine hydrochloride were added to obtain the needle layer 3D printing photosensitive ink.

[0067] Subsequently, the backing layer 3D printing photosensitive ink is added into the 3D printer and then light-cured printing is performed to print the backing layer, and then the needle body layer 3D printing photosensitive ink is added into the 3D printer and light-cured printing is performed on the backing layer to print the needle body layer, thereby obtaining a soluble microneedle patch;

[0068] 3D printing parameters: exposure time 20s, bottom layer exposure time 60s, layer thickness 0.05mm.

[0069] The prepared soluble microneedles were inserted into the mouse skin. After a puncture period of 30 minutes, the microneedle body layer was completely dissolved, and finally the backing layer was removed from the skin.

[0070] The removed backing layer was dissolved and recovered in 60°C ethanol, and the ethanol was dried to obtain a precipitate, which was then added to a new backing layer 3D printing photosensitive ink at a mass fraction of 25% to fully dissolve, thereby obtaining a recovered backing layer 3D printing photosensitive ink. The backing layer was 3D printed again, and the microneedle body layer was continued to be printed to obtain a soluble microneedle patch.

[0071] Example 6

[0072] ChCl, AA, and NIPAM were mixed in a molar ratio of 1:3:2, and then heated in a water bath at 70°C to dissolve to prepare a polymerizable eutectic solvent B. Then, a photoinitiator TPO was added at a mass ratio of 0.2% to obtain a backing layer 3D printing photosensitive ink.

[0073] ChCl and MA were mixed at a molar ratio of 1:10, and then heated in a water bath at 70°C to dissolve to prepare a polymerizable eutectic solvent A. Then, 2% by mass of a photoinitiator TPO and 0.1% by mass of chitosan-based nanoparticles with insulin as an active ingredient were added to obtain a needle layer 3D printing photosensitive ink.

[0074] Subsequently, the backing layer 3D printing photosensitive ink is added into the 3D printer and then light-cured printing is performed to print the backing layer, and then the needle body layer 3D printing photosensitive ink is added into the 3D printer and light-cured printing is performed on the backing layer to print the needle body layer, thereby obtaining a soluble microneedle patch;

[0075] 3D printing parameters: exposure time 30s, bottom layer exposure time 60s, layer thickness 0.02mm.

[0076] The prepared soluble microneedles were inserted into the mouse skin. After a puncture period of 20 minutes, the microneedle body layer was completely dissolved, and finally the backing layer was removed from the skin.

[0077] The removed backing layer was dissolved and recovered in 60°C ethanol, and the ethanol was dried to obtain a precipitate, which was then added to a new backing layer 3D printing photosensitive ink at a mass fraction of 10% to fully dissolve, thereby obtaining a recovered backing layer 3D printing photosensitive ink. The backing layer was 3D printed again, and the microneedle body layer was continued to be printed to obtain a soluble microneedle patch.

[0078] The present invention describes preferred embodiments and their effects. However, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0079] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

[0080] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A soluble microneedle patch that can be 3D printed by recyclable light curing, characterized in that: The soluble microneedle patch comprises a needle body layer and a backing layer; The raw materials for preparing the backing layer include a hydrogen bond acceptor, a hydrogen bond donor B and a photoinitiator; The raw materials for preparing the needle body layer include a hydrogen bond acceptor, a hydrogen bond donor A, a photoinitiator and an effective component.

2. A soluble microneedle patch that can be 3D printed by recyclable light curing according to claim 1, characterized in that: The hydrogen bond acceptor is at least one of choline chloride and N-vinyl pyrrolidone; The hydrogen bond donor A is at least one of itaconic acid, maleic acid, and N-isopropylacrylamide; The photoinitiator is at least one of 2,4,6 (trimethylbenzoyl) diphenylphosphine oxide and 2,4,6-trimethylbenzoyl ethylphosphinate; The active ingredient is at least one of a protein, a polypeptide, a gene, an antibody, an anesthetic, a vaccine, a chemically synthesized drug, a natural drug molecule, a cosmetic ingredient, and a nanoscale drug carrier; The hydrogen bond donor B is at least one of itaconic acid, maleic acid, hydroxyethyl methacrylate, N-isopropylacrylamide, glycerol, 3-acrylamidophenylboronic acid, and acrylic acid.

3. A soluble microneedle patch that can be 3D printed by recyclable light curing according to claim 1 or 2, characterized in that: The molar ratio of the hydrogen bond acceptor to the hydrogen bond donor A is 1:0.05-10; The molar ratio of the hydrogen bond acceptor to the hydrogen bond donor B is 1:0.05-10.

4. The soluble microneedle patch that can be 3D printed by recyclable light curing according to claim 1, characterized in that: Taking the total mass of the raw materials for preparing the needle body layer as 100%, the mass of the photoinitiator in the raw materials for preparing the needle body layer is 0.01% to 5%, and the mass of the effective component is greater than 0 and less than 40%.

5. The soluble microneedle patch that can be 3D printed by recyclable light curing according to claim 1, characterized in that: Taking the total mass of the raw materials for preparing the backing layer as 100%, the mass of the photoinitiator in the raw materials for preparing the backing layer is 0.01% to 5%.

6. A method for preparing a soluble microneedle patch that can be cyclically photocured by 3D printing, characterized in that The steps of the method include: (1) mixing a hydrogen bond acceptor and a hydrogen bond donor B in the raw materials for preparing the backing layer and heating the mixture to prepare a polymerizable eutectic solvent B, and then adding a photoinitiator in the raw materials for preparing the backing layer to mix the mixture to prepare a backing layer 3D printing ink; (2) mixing the hydrogen bond acceptor and hydrogen bond donor A in the raw materials for preparing the needle body layer and heating them to prepare a polymerizable eutectic solvent A, and then adding the photoinitiator and the active ingredient in the raw materials for preparing the needle body layer to mix and prepare a needle body layer 3D printing ink; (3) performing photocuring 3D printing using the backing layer 3D printing ink obtained in step (1) to obtain a backing layer; (4) Using the needle body layer 3D printing ink obtained in step (2) to perform photocuring 3D printing of the needle body layer on the backing layer to obtain a soluble microneedle patch.

7. An application of a soluble microneedle patch that can be cyclically photocured by 3D printing, characterized in that The steps of the method include: The soluble microneedle patch is placed tightly against the skin and the needle layer is inserted into the skin. After a set period of time, the needle layer dissolves in the skin.

8. The use of a soluble microneedle patch that can be cyclically photocured by 3D printing according to claim 7, characterized in that: The setting time is 10-60min.

9. The soluble microneedle patch capable of recyclable photocuring 3D printing according to claim 7, characterized in that: The backing layer is removed from the skin for recycling. The recycling method is: dissolving the removed backing layer in ethanol to obtain a recycling solution, and then drying the recycling solution to obtain a precipitate. The precipitate includes hydrogen bond acceptors and hydrogen bond donors B used as raw materials for preparing the backing layer. The obtained precipitate can be used as a raw material for configuring the backing layer 3D printing ink.

10. The soluble microneedle patch capable of recyclable photocuring 3D printing according to claim 7, characterized in that: When the removed backing layer is dissolved in ethanol, the temperature of the ethanol is 50-70°C.

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