Response type microneedle patch for diabetes wound healing as well as preparation method and application of response type microneedle patch

Abstract

The invention relates to the technical field of biomedical materials, in particular to a microneedle patch for diabetes wound healing and a preparation method and application thereof. The microneedle patch comprises a substrate and a microneedle array arranged on the surface of the substrate, the substrate is prepared from a first raw material system comprising polyvinyl alcohol, phenylboronic acid modified oxidized hyaluronic acid, bromothymol blue and first drug micromolecules; the microneedle array is prepared from a second raw material system which comprises methylacryloylated gelatin, 2-(methylacryloyloxy) ethyl choline phosphate and platelet cell membrane wrapped MOF loaded second drug micromolecules. The microneedle patch has the characteristics of promoting angiogenesis, being excellent in antibacterial property and slow release, also has sensitive pH responsiveness and ROS responsiveness at the same time, can adjust the release dose of the medicine according to the wound surface microenvironment change (pH value change and ROS concentration change), can monitor the wound surface state in real time according to the wound surface pH value change indication, and is suitable for being popularized and used clinically.

Description

Technical Field

[0001] The present invention relates to the technical field of biomedical materials, and particularly to a microneedle patch for diabetic wound healing, a preparation method thereof, and an application thereof. Background Art

[0002] Diabetes, as a common chronic metabolic disease, has an increasing incidence rate and number of patients globally year by year. The main feature of diabetes is the long-term elevation of blood glucose level, and long-term hyperglycemia can cause various complications, such as retinopathy, nephropathy, neuropathy, diabetic foot ulcers, etc.

[0003] Diabetic wounds belong to chronic wounds, and their healing process is delayed and prone to develop into chronic ulcers. In severe cases, it may lead to infection, gangrene, and even amputation. During the healing process of diabetic wounds, factors such as bacterial infection and insufficient neovascularization not only seriously affect the wound healing process but also increase the risk of secondary infection, ultimately resulting in a decline in the quality of life of patients and an increase in the medical burden. Therefore, there is an urgent need to develop strategies for effectively promoting the healing of diabetic wounds.

[0004] In recent years, microneedles (MNs) have received extensive attention as a novel drug delivery system. The height of microneedles is generally between 10 μm and 2000 μm, and the width is generally between 10 μm and 50 μm. After loading the target drug, they can penetrate the skin epidermis layer to achieve the purpose of targeted drug delivery in the skin. However, existing microneedles lack intelligent responsiveness, and thus cannot adjust the drug release dose according to changes in the wound microenvironment (such as changes in pH value, changes in the concentration of reactive oxygen species (ROS), etc.), which limits their application. Summary of the Invention

[0005] The present invention provides a microneedle patch for diabetic wound healing, which has the functions of promoting angiogenesis, excellent antibacterial properties, and sustained-release characteristics. It also has sensitive pH responsiveness and ROS responsiveness, can adjust the drug release dose according to changes in the wound microenvironment (pH value change, ROS concentration change), and can indicate and monitor the wound state in real time according to the change in the wound pH value.

[0006] The present invention also provides a preparation method of a microneedle patch for diabetic wound healing. Through this preparation method, the above-mentioned microneedle patch can be prepared. Therefore, the microneedle patch has the functions of promoting angiogenesis, excellent antibacterial properties, and sustained-release characteristics. It also has sensitive pH responsiveness and ROS responsiveness, can adjust the drug release dose according to changes in the wound microenvironment (pH value change, ROS concentration change), and can indicate and monitor the wound state in real time according to the change in the wound pH value.

[0007] The present invention also provides a drug, which includes the above-mentioned microneedle patch. Therefore, this drug also has the properties of promoting angiogenesis, excellent antibacterial performance and sustained-release characteristics, and at the same time has sensitive pH responsiveness and ROS responsiveness. It can adjust the release dose of the drug according to the changes in the wound microenvironment (pH value change, ROS concentration change), and can indicate and monitor the wound state in real time according to the change of the wound pH value.

[0008] In the first aspect of the present invention, there is provided a microneedle patch for diabetic wound healing, and the microneedle patch includes a substrate and a microneedle array disposed on the surface of the substrate;

[0009] The substrate is made of a first raw material system including polyvinyl alcohol, phenylboronic acid-modified oxidized hyaluronic acid, bromothymol blue and a first drug small molecule;

[0010] The microneedle array is made of a second raw material system including methacrylated gelatin, 2-(methacryloyloxy)ethylcholine phosphate and a second drug small molecule loaded with platelet cell membrane-coated MOF.

[0011] For the microneedle patch for diabetic wound healing as described above, in the microneedle patch, the mass ratio of the substrate to the microneedle array is (2-5):1.

[0012] For the microneedle patch for diabetic wound healing as described above, the microneedle array contains at least 100 needle tips, the height of the needle tips is 500μm - 900μm, and the needle tip spacing is 300μm - 800μm.

[0013] For the microneedle patch for diabetic wound healing as described above, the first drug small molecule includes amikacin, and the second drug small molecule includes deferoxamine mesylate.

[0014] In the second aspect of the present invention, there is provided a preparation method of the microneedle patch for diabetic wound healing as described above, including the following steps:

[0015] Step 1, respectively take methacrylated gelatin and 2-(methacryloyloxy)ethylcholine phosphate, add RO water to make a methacrylated gelatin solution and a 2-(methacryloyloxy)ethylcholine phosphate solution; mix the methacrylated gelatin solution, the 2-(methacryloyloxy)ethylcholine phosphate solution, the platelet cell membrane-coated MOF loaded with the second drug small molecule and a photoinitiator to obtain a precursor solution of the microneedle tips;

[0016] Step 2, fill the precursor solution of the microneedle tips into a microneedle array mold, and after the first centrifugation treatment, carry out a cross-linking reaction under ultraviolet light irradiation to obtain a microneedle array;

[0017] Step 3: Respectively take phenylboronic acid-modified oxidized hyaluronic acid and polyvinyl alcohol, and add RO water to prepare a phenylboronic acid-modified oxidized hyaluronic acid solution and a polyvinyl alcohol solution; mix the phenylboronic acid-modified oxidized hyaluronic acid solution, the polyvinyl alcohol solution, the first drug small molecule, and bromothymol blue to obtain a precursor solution of the substrate.

[0018] Step 4: Add the precursor solution of the substrate to the microneedle array mold in Step 2, and after the second centrifugation treatment and drying treatment, the microneedle patch containing the substrate and the microneedle array is obtained.

[0019] The preparation method of the microneedle patch for diabetic wound healing as described above, wherein the concentration of methacrylated gelatin in the methacrylated gelatin solution is 100 mg / mL to 300 mg / mL, and the concentration of 2-(methacryloyloxy)ethylcholine phosphate in the 2-(methacryloyloxy)ethylcholine phosphate solution is 100 mg / mL to 300 mg / mL.

[0020] The preparation method of the microneedle patch for diabetic wound healing as described above, wherein in the precursor solution of the microneedle tip, the mass ratio of methacrylated gelatin, 2-(methacryloyloxy)ethylcholine phosphate, and the second drug small molecule in the platelet cell membrane-coated MOF loaded with the second drug small molecule is 20:1:(0.2 - 1.2).

[0021] The preparation method of the microneedle patch for diabetic wound healing as described above, wherein the concentration of polyvinyl alcohol in the polyvinyl alcohol solution is 25 mg / mL to 35 mg / mL, and the concentration of phenylboronic acid-modified oxidized hyaluronic acid in the phenylboronic acid-modified oxidized hyaluronic acid solution is 8 mg / mL to 12 mg / mL.

[0022] The preparation method of the microneedle patch for diabetic wound healing as described above, wherein in the precursor solution of the substrate, the mass ratio of phenylboronic acid-modified oxidized hyaluronic acid, polyvinyl alcohol, and the first drug small molecule is 500:1500:(0.1 - 1), and the mass fraction of bromothymol blue is 0.01% to 0.1%.

[0023] The third aspect of the present invention provides a medical device, including the microneedle patch for diabetic wound healing as described above.

[0024] Compared with the prior art, the solution of the present invention has at least the following effects:

[0025] The microneedle patch for diabetic wound healing provided by the present invention includes a substrate and a microneedle array disposed on the surface of the substrate; the substrate is made of a first raw material system including polyvinyl alcohol, phenylboronic acid-modified oxidized hyaluronic acid, bromothymol blue, and a first small molecule drug; the microneedle array is made of a second raw material system including methacrylated gelatin, 2-(methacryloyloxy)ethylcholine phosphate, and platelet cell membrane-coated MOF loaded with a second small molecule drug. First, the microneedle patch has the ability to promote angiogenesis and can accelerate the later healing process of diabetic wounds; second, the microneedle patch has excellent antibacterial properties and can effectively treat early infections of diabetic wounds, improving the microenvironment for diabetic wound healing; third, the microneedle patch has a sustained-release characteristic and can slowly release drugs (such as deferoxamine mesylate); fourth, the microneedle patch has both sensitive pH responsiveness and ROS responsiveness, and can adjust the release dose of drugs according to changes in the wound microenvironment (pH value change, ROS concentration change); fifth, the microneedle patch can change color according to the change in the local pH value of the wound, realizing visual monitoring of wound signals (that is, it can indicate the real-time monitoring of the wound state according to the change in the local pH value of the wound), and is suitable for popularization and use in clinical practice. Brief Description of the Drawings

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0027] Figure 1 1H NMR spectra of phenylboronic acid-modified oxidized hyaluronic acid (PHA), oxidized hyaluronic acid (OHA), and hyaluronic acid (HA) in the present invention;

[0028] Figure 2 Appearance and scanning electron microscope images of the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention; among them, Figure 2 A in is the appearance of the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention; Figure 2 B in is the local scanning electron microscope image of the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention; Figure 2 C in is the scanning electron microscope image of a single needle tip in the microneedle patch in Example 9 of the present invention;

[0029] Figure 3 Drug release curves of test materials prepared from precursor solutions of different microneedle tips in the present invention;

[0030] Figure 4 Drug release curves of the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention in PBS buffers with different pH values and in PBS solutions with different concentrations of H2O2; wherein, Figure 4 A is the drug release curve of the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 in PBS solutions with different concentrations of H2O2, Figure 4 B is the drug release curve of the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 in PBS buffers with different pH values;

[0031] Figure 5 Display photos of the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention in culture plates with 3% agar solution of different pH values;

[0032] Figure 6 Results of in vitro experiments in the present invention;

[0033] Figure 7 Results of in vivo experiments in the present invention;

[0034] Figure 8 Microscopic photographing results under different treatments in the present invention;

[0035] Figure 9 Statistical chart of angiogenesis rate under different treatments in the present invention;

[0036] Figure 10 1H NMR spectrum of 2-(methacryloyloxy)ethylcholine phosphate (MCP) in the present invention. Detailed implementation manners

[0037] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. For those not specified in the embodiments regarding specific technologies or conditions, they shall be carried out according to the technologies or conditions described in the literature in the field or according to the product specifications. For reagents or instruments not specified by the manufacturer, they are all conventional products that can be obtained through commercial purchases.

[0038] It should be noted that the descriptions involving "first", "second", etc. in the present invention are used to distinguish similar objects and not to describe a specific order or sequence, and thus should not be construed as a limitation to the present invention.

[0039] The first aspect of the present invention provides a microneedle patch for diabetic wound healing, and the microneedle patch includes a substrate and a microneedle array disposed on the surface of the substrate;

[0040] The substrate is made of a first raw material system including polyvinyl alcohol, phenylboronic acid-modified oxidized hyaluronic acid, bromothymol blue, and a first small molecule drug;

[0041] The microneedle array is made of a second raw material system including methacrylated gelatin, 2-(methacryloyloxy)ethylcholine phosphate, and platelet cell membrane-coated MOF loaded with a second small molecule drug.

[0042] The present invention does not particularly limit the specific shape of the above substrate. In some embodiments, the shape of the substrate can be square, circular, oval, rectangular, or polygonal.

[0043] The present invention does not particularly limit the specific sources of the respective raw materials for preparing the above microneedle patch, which can be obtained through commercial channels or prepared by methods well-known in the art. For example, the above phenylboronic acid-modified oxidized hyaluronic acid can be prepared through the following process:

[0044] ① Preparation of oxidized hyaluronic acid

[0045] Respectively take hyaluronic acid and sodium periodate, and add RO water to make a hyaluronic acid solution and a sodium periodate solution;

[0046] Mix the hyaluronic acid solution and the sodium periodate solution and carry out a light-shielding reaction for 4 h to 8 h to obtain a reaction solution;

[0047] Then add ethylene glycol to the reaction solution and react for 0.5 h to 2 h to obtain a first reaction product;

[0048] Carry out a first dialysis treatment and a first freeze-drying treatment on the first reaction product in sequence to obtain oxidized hyaluronic acid;

[0049] ② Preparation of phenylboronic acid-modified oxidized hyaluronic acid

[0050] Take oxidized hyaluronic acid and add RO water to make an oxidized hyaluronic acid solution, and then mix 3-aminophenylboronic acid with the oxidized hyaluronic acid solution and react for 10 h to 15 h to obtain a second reaction product;

[0051] Carry out a second dialysis treatment and a second freeze-drying treatment on the second reaction product in sequence to obtain phenylboronic acid-modified oxidized hyaluronic acid.

[0052] The above 2-(methacryloyloxy)ethylcholine phosphate (MCP) can be prepared through the following process:

[0053] Methanol, triethylamine, 2-chloro-2-oxo-1,3,2-dioxaphospholane and tetrahydrofuran were mixed and reacted at -20 °C for 3 h, then transferred to room temperature and reacted for 4 h to obtain the third reaction product; the third reaction product was successively filtered by suction and washed to obtain a pale yellow oily liquid; the pale yellow oily liquid was rotary evaporated, then acetonitrile and hydroquinone were added and mixed at 0 °C to obtain a first mixture, N,N-dimethylaminoethyl methacrylate was added to the first mixture and reacted at 0 °C for 3 h, then transferred to 55 °C and reacted for 24 h to obtain the fourth reaction product; the fourth reaction product was rotary evaporated and then added to frozen tetrahydrofuran to form a reddish-brown precipitate, and the reddish-brown precipitate was purified by column chromatography to obtain 2-(methacryloyloxy)ethylcholine phosphate (MCP).

[0054] Specifically, the object prepared in the present invention is a microneedle patch for diabetic wound healing, and the microneedle patch includes a substrate and a microneedle array disposed on the surface of the substrate; the substrate is made of a first raw material system including polyvinyl alcohol, phenylboronic acid-modified oxidized hyaluronic acid, bromothymol blue and a first drug small molecule; the microneedle array is made of a second raw material system including methacrylated gelatin, 2-(methacryloyloxy)ethylcholine phosphate and platelet cell membrane-coated MOF loaded with a second drug small molecule. The microneedle patch has the functions of promoting angiogenesis, excellent antibacterial performance and slow-release characteristics, and also has sensitive pH responsiveness and ROS responsiveness at the same time, can adjust the release dose of the drug according to the changes in the wound microenvironment (pH value change, ROS concentration change), and can indicate and monitor the wound state in real time according to the change of the wound pH value, and is suitable for popularization and use in clinical practice.

[0055] In a specific embodiment, in the above microneedle patch, the mass ratio of the substrate to the microneedle array is (2-5):1.

[0056] When the parameter of the mass ratio of the substrate to the microneedle array in the above microneedle patch is within the above range, the prepared microneedle patch has the functions of promoting angiogenesis, excellent antibacterial performance and slow-release characteristics, and also has sensitive pH responsiveness and ROS responsiveness at the same time.

[0057] In a specific embodiment, in the above microneedle array, there are at least 100 needle tips, the height of the needle tips is 500 μm - 900 μm, and the distance between the needle tips is 300 μm - 800 μm.

[0058] In the present invention, the above-mentioned distance between the needle tips refers to the distance between two needle tips.

[0059] The present invention does not particularly limit the specific shape of the above-mentioned needle tips. In some embodiments, the shape of the needle tips can be a triangular pyramid.

[0060] When the parameters of the number of needle tips, height, and needle tip spacing of the microneedle array are within the above ranges, it is beneficial to prepare the above microneedle patch with skin penetration, drug delivery, and adaptation to different tissues.

[0061] In a specific embodiment, the above first drug small molecule includes amikacin, and the above second drug small molecule includes deferoxamine mesylate.

[0062] When the first drug small molecule is amikacin, the substrate in the microneedle patch can achieve the intelligent release of amikacin according to the changes in the wound microenvironment (pH value change, ROS concentration change). At different pH values and / or ROS concentrations, the release dose of amikacin is different, indicating that the microneedle patch has sensitive pH responsiveness and ROS responsiveness;

[0063] When the second drug small molecule is deferoxamine mesylate, the needle tips of the microneedle array in the microneedle patch can play a role in the sustained release of deferoxamine mesylate, indicating that the microneedle patch has the property of drug sustained release.

[0064] The second aspect of the present invention provides a preparation method of the above microneedle patch for diabetic wound healing, including the following steps:

[0065] Step 1, respectively take methacrylated gelatin and 2-(methacryloyloxy)ethylcholine phosphate, add RO water to make a methacrylated gelatin solution and a 2-(methacryloyloxy)ethylcholine phosphate solution; mix the methacrylated gelatin solution, the 2-(methacryloyloxy)ethylcholine phosphate solution, platelet cell membrane-coated MOF loaded with the second drug small molecule and a photoinitiator to obtain a precursor solution for the microneedle tips;

[0066] Step 2, fill the precursor solution for the microneedle tips into a microneedle array mold, and after the first centrifugation treatment, carry out a cross-linking reaction under ultraviolet light irradiation to obtain a microneedle array;

[0067] Step 3, respectively take phenylboronic acid-modified oxidized hyaluronic acid and polyvinyl alcohol, add RO water to make a phenylboronic acid-modified oxidized hyaluronic acid solution and a polyvinyl alcohol solution; mix the phenylboronic acid-modified oxidized hyaluronic acid solution, the polyvinyl alcohol solution, the first drug small molecule and bromothymol blue to obtain a precursor solution for the substrate;

[0068] Step 4, add the precursor solution for the substrate to the microneedle array mold in Step 2, and after the second centrifugation treatment and drying treatment, the microneedle patch containing the substrate and the microneedle array is obtained.

[0069] The present invention does not make specific limitations on the specific equipment or instruments for each treatment in the above preparation method.

[0070] The present invention does not particularly limit the specific material and shape of the above micro-needle array mold. In some embodiments, the above micro-needle array mold can be a mold made of polydimethylsiloxane (PDMS).

[0071] The present invention does not particularly limit the specific photoinitiator, and photoinitiators well-known in the art can be used. For example, the photoinitiator can be photoinitiator LAP.

[0072] The present invention does not particularly limit the specific parameters of the rotation speed and time of the above first centrifugation treatment, and can be selected according to specific needs.

[0073] The present invention also does not particularly limit the specific parameters of the rotation speed and time of the above second centrifugation treatment, and can be selected according to specific needs.

[0074] The present invention does not particularly limit the specific parameters of the temperature and time of the above drying treatment, and can be selected according to specific needs.

[0075] Through the above preparation, the present invention can prepare the above micro-needle patch that has the functions of promoting angiogenesis, excellent antibacterial performance and slow-release characteristics, and also has sensitive pH responsiveness and ROS responsiveness, can adjust the release dose of the drug according to the changes in the wound microenvironment (pH value change, ROS concentration change), and can indicate and monitor the wound state in real time according to the change of the wound pH value.

[0076] In the present invention, the above RO water (Reverses Osmosis) is reverse osmosis water, that is, pure water.

[0077] In a specific embodiment, the concentration of methacrylated gelatin in the above methacrylated gelatin solution is 100 mg / mL to 300 mg / mL, and the concentration of 2-(methacryloyloxy)ethylcholine phosphate in the above 2-(methacryloyloxy)ethylcholine phosphate solution is 100 mg / mL to 300 mg / mL.

[0078] When the parameters of the concentration of the methacrylated gelatin solution and the parameters of the concentration of the 2-(methacryloyloxy)ethylcholine phosphate solution are each within the above ranges, it is beneficial to promote cell adhesion, cell proliferation and improve the biocompatibility of the material, so as to prepare a micro-needle patch that has the functions of promoting angiogenesis, excellent antibacterial performance and slow-release characteristics, and also has sensitive pH responsiveness and ROS responsiveness, can adjust the release dose of the drug according to the changes in the wound microenvironment (pH value change, ROS concentration change), and can indicate and monitor the wound state in real time according to the change of the wound pH value.

[0079] In a specific embodiment, in the precursor solution of the microneedle tip, the mass ratio of methacrylated gelatin, 2-(methacryloyloxy)ethylcholine phosphate, and the second small drug molecule loaded by platelet cell membrane-coated MOF is 20:1:(0.2 - 1.2).

[0080] When the parameters of the mass ratio of methacrylated gelatin, 2-(methacryloyloxy)ethylcholine phosphate, and the second small drug molecule loaded by platelet cell membrane-coated MOF in the precursor solution of the microneedle tip are within the above ranges, the release concentration of the second drug can be regulated.

[0081] In a specific embodiment, the concentration of polyvinyl alcohol in the above polyvinyl alcohol solution is 25 mg / mL - 35 mg / mL, and the concentration of phenylboronic acid-modified oxidized hyaluronic acid in the above phenylboronic acid-modified oxidized hyaluronic acid solution is 8 mg / mL - 12 mg / mL.

[0082] When the parameters of the concentration of the phenylboronic acid-modified oxidized hyaluronic acid solution and the concentration of the polyvinyl alcohol solution are each within the above ranges, it is beneficial for the subsequent preparation of a microneedle patch with mechanical properties.

[0083] In a specific embodiment, in the precursor solution of the substrate, the mass ratio of phenylboronic acid-modified oxidized hyaluronic acid, polyvinyl alcohol, and the first small drug molecule is 500:1500:(0.1 - 1), and the mass fraction of bromothymol blue is 0.01% - 0.1%.

[0084] When the parameters of the mass ratio of phenylboronic acid-modified oxidized hyaluronic acid, polyvinyl alcohol, and the first small drug molecule in the precursor solution of the substrate are within the above ranges, the release of the first small drug molecule can be regulated.

[0085] When the mass fraction of bromothymol blue in the precursor solution of the substrate is within the above ranges, it is beneficial for the preparation of a microneedle patch that can indicate and monitor the wound state in real time according to the change in the pH value of the wound surface.

[0086] The third aspect of the present invention provides a drug, including the above microneedle patch for diabetic wound healing. Therefore, this drug also has the functions of promoting angiogenesis, excellent antibacterial properties, and sustained-release characteristics, and at the same time has sensitive pH responsiveness and ROS responsiveness. It can adjust the release dose of the drug according to the changes in the wound microenvironment (pH value change, ROS concentration change), and can indicate and monitor the wound state in real time according to the change in the pH value of the wound surface.

[0087] Hereinafter, the present invention will be further introduced through specific examples.

[0088] Example 1

[0089] The preparation method of the precursor solution of the microneedle tip provided in this embodiment includes the following steps:

[0090] (1) Preparation of 2-(methacryloyloxy)ethylcholine phosphate (MCP)

[0091] Dissolve 0.5 mL of 2-chloro-2-oxo-1,3,2-dioxaphospholane in 10 mL of tetrahydrofuran to obtain a 2-chloro-2-oxo-1,3,2-dioxaphospholane solution;

[0092] Dissolve 1290 μL of methanol and 4440 μL of triethylamine in a flask containing 20 mL of tetrahydrofuran, and then dropwise add the 2-chloro-2-oxo-1,3,2-dioxaphospholane solution into the flask. React at -20 °C for 3 h, then transfer to room temperature and react for 4 h to obtain reaction product A; after filtering the reaction product A by suction filtration, wash it with tetrahydrofuran to obtain a pale yellow oily liquid; after rotary evaporation of the pale yellow oily liquid, add 40 mL of acetonitrile and 200 mg of hydroquinone and mix at 0 °C to obtain a first mixture. Add 10 mL of N,N-dimethylaminoethyl methacrylate to the first mixture and react at 0 °C for 3 h, then transfer to 55 °C and react for 24 h to obtain reaction product B; after rotary evaporation of reaction product B, add it to frozen tetrahydrofuran to form a reddish-brown precipitate, and finally purify the reddish-brown precipitate by column chromatography to obtain the final product 2-(methacryloyloxy)ethylcholine phosphate (MCP) (the 1H NMR spectrum of MCP is as Figure 10 shown).

[0093] (2) Preparation of the precursor solution of the microneedle tip

[0094] Mix gelatin methacrylate (GELMA) with a double bond substitution degree of 90% and reverse osmosis water (RO water), and then place it in a water bath at 37 °C and heat for 30 minutes to fully dissolve the gelatin methacrylate to prepare a 0.8 mL gelatin methacrylate solution with a concentration of 250 mg / mL;

[0095] Mix 2-(methacryloyloxy)ethylcholine phosphate with RO water to prepare a 50 μL 2-(methacryloyloxy)ethylcholine phosphate solution with a concentration of 200 mg / mL;

[0096] Mix 0.8 mL of gelatin methacrylate solution with a concentration of 250 mg / mL, 50 μL of 2-(methacryloyloxy)ethylcholine phosphate solution with a concentration of 200 mg / mL, platelet cell membrane-coated MOF loaded with 10 mg of deferoxamine mesylate (drug loading rate is 12.22%, encapsulation efficiency is 40.56%, purchased from Aladdin), and 2 mg of photoinitiator LAP to obtain the precursor solution of the microneedle tip (GELMA / MCP-PL@MOF).

[0097] Example 2 (without adding 2-(methacryloyloxy)ethylcholine phosphate)

[0098] The preparation method of the precursor solution of the microneedle tip provided in this example is basically the same as that in Example 1, except that:

[0099] (2) Preparation of the precursor solution of the microneedle tip

[0100] Mix 0.8 mL of methacrylated gelatin solution with a concentration of 250 mg / mL, 10 mg of deferoxamine mesylate loaded on platelet cell membrane-wrapped MOF, and 2 mg of photoinitiator LAP to obtain the precursor solution of the microneedle tip (GELMA-PL@MOF).

[0101] Example 3

[0102] The preparation method of the precursor solution of the microneedle tip provided in this example is basically the same as that in Example 1, except that:

[0103] (2) Preparation of the precursor solution of the microneedle tip

[0104] Mix 0.8 mL of methacrylated gelatin solution with a concentration of 250 mg / mL, 50 μL of 2-(methacryloyloxy)ethylcholine phosphate solution with a concentration of 200 mg / mL, 10 mg of deferoxamine mesylate loaded on MOF (purchased from Aladdin), and 2 mg of photoinitiator LAP to obtain the precursor solution of the microneedle tip (GELMA / MCP-MOF).

[0105] Example 4

[0106] The preparation method of the precursor solution of the microneedle tip provided in this example is basically the same as that in Example 1, except that:

[0107] (2) Preparation of the precursor solution of the microneedle tip

[0108] Mix 50 μL of 2-(methacryloyloxy)ethylcholine phosphate solution with a concentration of 200 mg / mL, 10 mg of deferoxamine mesylate loaded on MOF, and 2 mg of photoinitiator LAP to obtain the precursor solution of the microneedle tip (GELMA-MOF).

[0109] Example 5

[0110] The preparation method of the precursor solution of the microneedle tip provided in this example is basically the same as that in Example 1, except that:

[0111] (2) Preparation of the precursor solution of the microneedle tip

[0112] Mix 0.8 mL of a methacrylated gelatin solution with a concentration of 250 mg / mL and 2 mg of the photoinitiator LAP to obtain the precursor solution for the microneedle tip.

[0113] Example 6

[0114] The method for preparing the precursor solution of the substrate provided in this example includes the following steps:

[0115] (1) Preparation of phenylboronic acid-modified oxidized hyaluronic acid:

[0116] ① Preparation of oxidized hyaluronic acid

[0117] Dissolve 1.5 g of hyaluronic acid in 150 mL of RO water to make a hyaluronic acid solution;

[0118] Dissolve 0.5 g of sodium periodate in 10 mL of RO water to make a sodium periodate solution;

[0119] Mix the hyaluronic acid solution and the sodium periodate solution and carry out a light-shielded reaction for 6 h to obtain a reaction solution;

[0120] Then add 2 mL of ethylene glycol to the reaction solution and react for 1 h to obtain reaction product A;

[0121] Perform dialysis treatment on reaction product A for 3 days, change the water 7 times during this period, and then perform freeze-drying treatment on the dialyzed reaction product A to obtain oxidized hyaluronic acid;

[0122] ② Preparation of phenylboronic acid-modified oxidized hyaluronic acid

[0123] Dissolve 1 g of oxidized hyaluronic acid in 50 mL of RO water to make an oxidized hyaluronic acid solution, and then mix the oxidized hyaluronic acid solution with 0.3 g of 3-aminophenylboronic acid and react for 12 h to obtain reaction product B;

[0124] Perform dialysis treatment on reaction product B for 3 days, change the water 7 times during this period, and then perform freeze-drying treatment on the dialyzed reaction product B to obtain phenylboronic acid-modified oxidized hyaluronic acid.

[0125] (2) Preparation of the precursor solution of the substrate

[0126] Dissolve 1.5 g of polyvinyl alcohol in 48.5 mL of RO water to make a polyvinyl alcohol solution;

[0127] Dissolve 0.5 g of phenylboronic acid-modified oxidized hyaluronic acid in 49 mL of RO water to make a phenylboronic acid-modified oxidized hyaluronic acid solution;

[0128] Mix the phenylboronic acid-modified oxidized hyaluronic acid solution, polyvinyl alcohol solution, 150 μg amikacin, and bromothymol blue to obtain the precursor solution of the substrate; in the precursor solution of the substrate, the mass fraction of bromothymol blue is 0.01%.

[0129] Example 7

[0130] The preparation method of the precursor solution of the substrate provided in this example is basically the same as that in Example 6, except that:

[0131] (2) Preparation of the precursor solution of the substrate

[0132] Mix the phenylboronic acid-modified oxidized hyaluronic acid solution and polyvinyl alcohol solution to obtain the precursor solution of the substrate.

[0133] Example 8

[0134] The preparation method of the precursor solution of the substrate provided in this example is basically the same as that in Example 6, except that:

[0135] (2) Preparation of the precursor solution of the substrate

[0136] Mix the phenylboronic acid-modified oxidized hyaluronic acid solution, polyvinyl alcohol solution, and bromothymol blue to obtain the precursor solution of the substrate; in the precursor solution of the substrate, the mass fraction of bromothymol blue is 0.01%.

[0137] Example 9

[0138] The preparation method of the microneedle patch for diabetic wound healing provided in this example includes the following steps:

[0139] S1, Fill 200 μL of the precursor solution (GELMA / MCP-PL@MOF) of the microneedle tip in Example 1 into a polydimethylsiloxane (PDMS) mold. After the first centrifugation treatment, scrape off the excess solution, and then carry out a cross-linking reaction under ultraviolet light irradiation to obtain a microneedle array;

[0140] S2, Add 800 μL of the precursor solution of the substrate in Example 6 to the polydimethylsiloxane (PDMS) mold in S1. After the second centrifugation treatment, scrape off the excess solution, and then after drying treatment, obtain a microneedle patch (DMN-AK / BTB / PL@MOF) containing the substrate and the microneedle array.

[0141] Example 10

[0142] The preparation method of the microneedle patch for diabetic wound healing provided in this example is basically the same as that in Example 9, except that:

[0143] The precursor solution of the microneedle tip in Example 1 (GELMA / MCP-PL@MOF) was replaced with the precursor solution of the microneedle tip in Example 3 (GELMA / MCP-MOF) to prepare a microneedle patch (DMN-AK / BTB / MOF) containing a substrate and a microneedle array.

[0144] Example 11

[0145] The preparation method of the microneedle patch for diabetic wound healing provided in this example is basically the same as that in Example 9, except that:

[0146] The precursor solution of the microneedle tip in Example 1 (GELMA / MCP-PL@MOF) was replaced with the precursor solution of the microneedle tip in Example 5 to prepare a microneedle patch (DMN-AK / BTB) containing a substrate and a microneedle array.

[0147] Example 12

[0148] The preparation method of the microneedle patch for diabetic wound healing provided in this example is basically the same as that in Example 9, except that:

[0149] The precursor solution of the microneedle tip in Example 1 (GELMA / MCP-PL@MOF) was replaced with the precursor solution of the microneedle tip in Example 5, and the precursor solution of the substrate in Example 6 was replaced with the precursor solution of the substrate in Example 7 to prepare a microneedle patch (Blank DMN) containing a substrate and a microneedle array.

[0150] Example 13

[0151] The preparation method of the microneedle patch for diabetic wound healing provided in this example is basically the same as that in Example 9, except that:

[0152] The precursor solution of the microneedle tip in Example 1 (GELMA / MCP-PL@MOF) was replaced with the precursor solution of the microneedle tip in Example 5, and the precursor solution of the substrate in Example 6 was replaced with the precursor solution of the substrate in Example 8 to prepare a microneedle patch (DMN-BTB) containing a substrate and a microneedle array.

[0153] Performance Test

[0154] 1. 1H NMR spectra of phenylboronic acid modified oxidized hyaluronic acid (PHA), oxidized hyaluronic acid (OHA), and hyaluronic acid (HA)

[0155] 1H NMR tests were performed on phenylboronic acid modified oxidized hyaluronic acid (PHA), oxidized hyaluronic acid (OHA), and hyaluronic acid (HA) in the present invention, and the results are as Figure 1 shown.

[0156] It can be seen from Figure 1 that in the hydrogen spectrum of OHA, a new signal peak with a chemical shift value of 5.2 ppm appears compared to the hydrogen spectrum of HA, which belongs to the proton peak of the hemiacetal formed by the aldehyde group and the adjacent hydroxyl group; while in the hydrogen spectrum of PHA, signal peaks at 7.2 ppm and 7.5 ppm appear, which are the characteristic proton peaks of the benzene ring. These results prove that both OHA and PHA are successfully synthesized.

[0157] 2. Morphology characterization

[0158] The microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention was photographed and tested by scanning electron microscopy, as Figure 2 shown.

[0159] It can be seen from Figure 2 that in Example 9 of the present invention, the microneedle patch has regular morphology and uniform tip morphology, which is a triangular pyramid structure, with a tip height of 820 μm and a distance between two tips of 500 μm.

[0160] 3. Responsiveness and sustained-release characteristics

[0161] (1) In order to explore the drug release ability of the tips of the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention: the precursor solutions of the microneedle tips in Examples 1-4 of the present invention were respectively cross-linked under ultraviolet light irradiation to obtain test materials GELMA / MCP-PL@MOF, test material GELMA-PL@MOF, test material GELMA / MCP-MOF, and test material GELMA-MOF. Then, the test materials GELMA / MCP-PL@MOF, test material GELMA-PL@MOF, test material GELMA / MCP-MOF, and test material GELMA-MOF were respectively immersed in 10 mL of PBS buffer solution and placed in an oscillating incubator at 37 °C and 100 rpm for oscillation. At regular time intervals, 2 mL of the sustained-release solution was taken, 2 mL of fresh PBS buffer solution was supplemented, and an enzyme-labeled instrument was used to measure the absorbance of the released drug deferoxamine mesylate (DFO), and the cumulative release amount of the drug was calculated according to its release standard curve. The results are as Figure 3 shown.

[0162] It can be seen from Figure 3It can be seen that the drug release rates among the GELMA-PL@MOF group, the GELMA / MCP-MOF group, and the GELMA-MOF group are approximately equal, with no significant differences. The cumulative drug release amounts within 72 h are 82.25%, 84.59%, and 83.53% respectively, while the cumulative drug release amount of the GELMA / MCP-PL@MOF group within 72 h is 75.56%. The drug release experiment from the needle tip can prove that the microneedle array in the microneedle patch provided by the present invention can play a role in sustained release of deferoxamine mesylate (DFO).

[0163] (2) To explore the drug-responsive release ability of the substrate of the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention: ① Immerse the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention in 10 mL of PBS buffer solutions with pH = 7.4, pH = 6.5, pH = 6.0, and pH = 5.5 respectively, then place them in an oscillating incubator at 37 °C and 100 rpm for oscillation. At specified time intervals, take 2 mL of the sustained-release solution, supplement 2 mL of fresh PBS buffer solution, measure the absorbance of the released drug amikacin (AK) at 340 nm using an enzyme-linked immunosorbent assay (ELISA) reader, and calculate the cumulative drug release amount according to its release standard curve. The results are as shown in Figure 4 Figure B; ② Immerse the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention in 10 mL of pure PBS solution, PBS solution with 0.2 mmol / L (0.2 mM) hydrogen peroxide (H2O2), PBS solution with 0.5 mmol / L (0.5 mM) H2O2, and PBS solution with 1 mmol / L (1 mM) H2O2 respectively, then place them in an oscillating incubator at 37 °C and 100 rpm for oscillation. At specified time intervals, take 2 mL of the sustained-release solution, supplement 2 mL of fresh PBS buffer solution, measure the absorbance of the released drug amikacin (AK) at 340 nm using an enzyme-linked immunosorbent assay (ELISA) reader, and calculate the cumulative drug release amount according to its release standard curve. The results are as shown in Figure 4 Figure A.

[0164] As can be seen from Figure 4 Figure A, with the increase in the concentration of H2O2, the drug release ability of AK is significantly accelerated. At 16 h, the cumulative drug release amounts of AK in pure PBS solution, PBS solution with 0.2 mmol / L H2O2, PBS solution with 0.5 mmol / L H2O2, and PBS solution with 1 mmol / L H2O2 are 64.92%, 69.91%, 78.59%, and 83.7% respectively, indicating that the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention has obvious ROS-responsive ability and can adjust the release dose of AK according to the change in ROS concentration.

[0165] Depend on Figure 4 It can be seen from Figure B that with the decrease of pH value, the release ability of AK drug is significantly accelerated. At 16 h, the cumulative release amounts of AK drug in PBS buffer solutions with pH = 7.4, pH = 6.5, pH = 6.0 and pH = 5.5 are 67.23%, 76.81%, 83.28% and 93.2%, respectively, indicating that the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention has obvious pH response ability and can adjust the release dose of AK according to the change of pH value.

[0166] 4. pH indicator test

[0167] Agar solutions with a mass fraction of 3% at pH = 7.4, pH = 7.0, pH = 6.8, pH = 6.6, pH = 6.2, and pH = 5.8 were prepared respectively and poured into culture plates for later use; the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention was placed in culture plates containing agar solutions with a mass fraction of 3% at pH = 7.4, pH = 7.0, pH = 6.8, pH = 6.6, pH = 6.2, and pH = 5.8, respectively, and incubated for 3 minutes. The color changes of the microneedle patches were recorded by photographing; Figure 5 These are photos showing the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention in a culture plate containing 3% agar solution at different pH values.

[0168] Depend on Figure 5 It can be seen that as the pH value increases, the color of the substrate in the microneedle patch (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention gradually changes from yellow to blue. This is because bromothymol blue (BTB) is loaded in the substrate, and the microneedle patch (DMN-AK / BTB / PL@MOF) in the present invention produces a significant color change. Therefore, the microneedle patch (DMN-AK / BTB / PL@MOF) provided by the present invention can change color according to the local pH value change of the wound surface, thereby realizing visual monitoring of the wound surface signal (i.e., it can monitor the wound surface status in real time according to the local pH value change of the wound surface).

[0169] 5. Antibacterial properties

[0170] (1) In vitro experiments

[0171] Test method: Prepare 1 mL of purified 10 7 CFU / mL fresh E.coli suspension (E.coli suspension), 1mL of purified 10 7Fresh bacterial suspension of S. aureus (S. aureus bacterial suspension) at CFU / mL and 1 mL of 10 purified 7 Fresh bacterial suspension of P. Aeruginosa (P. Aeruginosa bacterial suspension) at CFU / mL were respectively poured into 24-well cell culture plates; then the micro-needle patches to be tested were respectively added to the 24-well cell culture plates containing different bacterial suspensions and incubated in an incubator at 37 °C for 12 h to obtain bacterial solutions (experimental groups), and the bacterial solutions without adding micro-needle patches were used as blank control groups (Control), with 5 parallel samples in each group. After incubation, the bacterial solutions were diluted 100 times. After dilution, 100 μL of each bacterial solution was taken and spread on solid medium plates, and then the solid medium plates after spreading were cultured in a constant temperature incubator at 37 °C for 12 h, and finally taken out for photography;

[0172] The micro-needle patches in Example 9 of the present invention (DMN-AK / BTB / PL@MOF), the micro-needle patches in Example 11 (DMN-AK / BTB) and the micro-needle patches in Example 12 (Blank DMN) were respectively used as the micro-needle patches to be tested and carried out according to the above test method, and the results are as Figure 6 shown.

[0173] It can be Figure 6 seen that there are more colony formations in the plating results of the blank control group and the micro-needle patches (Blank DMN) in Example 12, indicating that Blank DMN has almost no antibacterial ability against S. aureus, P. Aeruginos and E. coli, while there are almost no colonies in the plating results of DMN-AK / BTB and DMN-AK / BT / PL@MOF, indicating that DMN-AK / BTB and DMN-AK / BT / PL@MOF have excellent antibacterial properties against S. aureus, P. Aeruginos and E. coli.

[0174] (2) In vivo experiment

[0175] A diabetic wound rat model was constructed to obtain diabetic wound rats, and the diabetic wound rats were randomly divided into 4 groups:

[0176] DMN-AK / BTB / PL@MOF treatment group (DMN-AK / BTB / PL@MOF): After treating diabetic wound rats with the micro-needle patches (DMN-AK / BTB / PL@MOF) in Example 9 of the present invention for 3 days, 100 μL of the interstitial fluid of the rat wound was taken for plating treatment, and after culturing for 24 h, photography records were taken;

[0177] Blank DMN treatment group (Blank DMN): After treating diabetic wound rats with the microneedle patch (Blank DMN) in Example 12 of the present invention for 3 days, 100 μL of the interstitial fluid of the rat wound was taken for plating treatment, and after culturing for 24 h, photographic records were taken;

[0178] DMN-BTB treatment group (DMN-BTB): After treating diabetic wound rats with the microneedle patch (DMN-BTB) in Example 13 of the present invention for 3 days, 100 μL of the interstitial fluid of the rat wound was taken for plating treatment, and after culturing for 24 h, photographic records were taken;

[0179] Control group (Control): After treating diabetic wound rats with physiological saline for 3 days, 100 μL of the interstitial fluid of the rat wound was taken for plating treatment, and after culturing for 24 h, photographic records were taken.

[0180] Figure 7 Photographs of the plates of the interstitial fluid of the rat wounds after different treatments.

[0181] As Figure 7 can be seen, for physiological saline, Blank DMN and DMN-BTB, a large number of bacterial colonies appeared, while there were only very few individual colonies in DMN-AK / BTB / PL@MOF. Therefore, it can be proved that the microneedle patch DMN-AK / BTB / PL@MOF provided by the present invention also has excellent antibacterial performance in vivo.

[0182] 6. Ability to promote angiogenesis

[0183] Matrigel matrix gel was placed in a 4 °C refrigerator overnight to melt. Before the experiment, the pipette tip box and 48-well plate were placed in a -20 °C refrigerator for pre-cooling in advance. HUVECs cells in the logarithmic growth phase were collected in advance. The Blank DMN in Example 12, DMN-AK / BTB in Example 11, DMN-AK / BTB / MOF in Example 10, and DMN-AK / BTB / PL@MOF in Example 9 were respectively sterilized by ultraviolet light and used as the microneedle patches to be tested;

[0184] Add 100 μL of Matrigel matrix gel to each well of a 48-well plate, spread it evenly in the 48-well plate, and incubate it at 37 °C and 5% CO2 for 1 h to form a gel. Collect HUVECs cells in the logarithmic growth phase and inoculate 5000 cells per well into the 48-well plate with Matrigel matrix gel, and supplement with DMEM-F12 medium (Gibco) (1 mL / well). Then add the test microneedle patch (ultraviolet-sterilized Blank DMN, DMN-AK / BTB, DMN-AK / BTB / MOF, or DMN-AK / BTB / PL@MOF) as the experimental group, and use the group without adding the microneedle patch as the blank control group (Control). Set 5 parallel samples in each group. After co-incubating for 6 h, take pictures with a microscope and record ( Figure 8 ), and quantify the angiogenesis rate using ImageJ software ( Figure 9 ).

[0185] As can be seen from Figure 8 and Figure 9 , compared with the blank control group (Control), Blank DMN and DMN-AK / BTB do not have obvious ability to promote angiogenesis, while DMN-AK / BTB / MOF and DMN-AK / BTB / PL@MOF have strong ability to promote angiogenesis, which is because deferoxamine mesylate is added; compared with DMN-AK / BTB / MOF, the ability of DMN-AK / BTB / PL@MOF to promote angiogenesis is enhanced, which is because MOF loaded with deferoxamine mesylate is wrapped by platelet cell membrane.

[0186] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A microneedle patch for diabetic wound healing, characterized in that, The microneedle patch includes a substrate and a microneedle array disposed on the surface of the substrate; The substrate is made of a first raw material system including polyvinyl alcohol, phenylboronic acid-modified oxidized hyaluronic acid, bromothymol blue, and a first small molecule drug; The microneedle array is made of a second raw material system including methacrylated gelatin, 2-(methacryloyloxy)ethylcholine phosphate, and a second small molecule drug loaded on MOF encapsulated by platelet cell membranes; 2. The microneedle patch for diabetic wound healing according to claim 1, wherein In the microneedle patch, the mass ratio of the substrate to the microneedle array is (2-5):

1.

3. The microneedle patch for diabetic wound healing according to claim 1, wherein The microneedle array contains at least 100 needle tips, the height of the needle tips is 500μm - 900μm, and the needle tip spacing is 300μm - 800μm.

4. The microneedle patch for diabetic wound healing according to claim 1, wherein The first small molecule drug includes amikacin, and the second small molecule drug includes deferoxamine mesylate.

5. A method for preparing the microneedle patch for diabetic wound healing according to any one of claims 1 to 4, characterized in that, It includes the following steps: Step 1, separately take methacrylated gelatin and 2-(methacryloyloxy)ethylcholine phosphate, add RO water to make a methacrylated gelatin solution and a 2-(methacryloyloxy)ethylcholine phosphate solution; mix the methacrylated gelatin solution, the 2-(methacryloyloxy)ethylcholine phosphate solution, the second small molecule drug loaded on MOF encapsulated by platelet cell membranes, and a photoinitiator to obtain a precursor solution for the microneedle tips; Step 2, fill the precursor solution for the microneedle tips into a microneedle array mold, and after the first centrifugation treatment, carry out a cross-linking reaction under ultraviolet light irradiation to obtain a microneedle array; Step 3, separately take phenylboronic acid-modified oxidized hyaluronic acid and polyvinyl alcohol, add RO water to make a phenylboronic acid-modified oxidized hyaluronic acid solution and a polyvinyl alcohol solution; mix the phenylboronic acid-modified oxidized hyaluronic acid solution, the polyvinyl alcohol solution, the first small molecule drug, and bromothymol blue to obtain a precursor solution for the substrate; Step 4, add the precursor solution for the substrate to the microneedle array mold in Step 2, and after the second centrifugation treatment and drying treatment, the microneedle patch containing the substrate and the microneedle array is obtained.

6. The preparation method of the microneedle patch for diabetic wound healing according to claim 5, characterized in that, The concentration of methacrylated gelatin in the methacrylated gelatin solution is 100mg / mL - 300mg / mL, and the concentration of 2-(methacryloyloxy)ethylcholine phosphate in the 2-(methacryloyloxy)ethylcholine phosphate solution is 100mg / mL - 300mg / mL.

7. The preparation method of the microneedle patch for diabetic wound healing according to claim 5, characterized in that, In the precursor solution for the microneedle tips, the mass ratio of methacrylated gelatin, 2-(methacryloyloxy)ethylcholine phosphate, and the second small molecule drug in the second small molecule drug loaded on MOF encapsulated by platelet cell membranes is 20:1:(0.2 - 1.2).

8. The preparation method of the microneedle patch for diabetic wound healing according to claim 5, characterized in that, The concentration of polyvinyl alcohol in the polyvinyl alcohol solution is 25mg / mL - 35mg / mL, and the concentration of phenylboronic acid-modified oxidized hyaluronic acid in the phenylboronic acid-modified oxidized hyaluronic acid solution is 8mg / mL - 12mg / mL.

9. The preparation method of the microneedle patch for diabetic wound healing according to claim 5, wherein, In the precursor solution for the substrate, the mass ratio of phenylboronic acid-modified oxidized hyaluronic acid, polyvinyl alcohol, and the first small molecule drug is 500:1500:(0.1 - 1), and the mass fraction of bromothymol blue is 0.01% - 0.1%.

10. A medical device, characterized in that, Comprising the microneedle patch for diabetic wound healing according to any one of claims 1 to 4.

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